epiH :: Epidemiology and Health

Original Article Risk of dementia according to the severity of chronic periodontitis in Korea: a nationwide retrospective cohort study

Seon-Rye Kim, Minkook Son, Yu-Rin Kim, Hyun-Kyung Kang Epidemiol Health. 2022;44:e2022077.

Original Article The associations of job strain and leisure-time physical activity with the risk of hypertension: the population-based Midlife in the United States cohort study

Xinyue Liu, Timothy A. Matthews, Liwei Chen, Jian Li Epidemiol Health. 2022;44:e2022073.

Abstract: OBJECTIVES:
We investigated the risk of dementia in older adults with chronic periodontitis according to the severity of periodontitis.
METHODS:
Data on patients with chronic periodontitis were extracted from the National Health Insurance Service-Senior cohort database from 2002 to 2014. Among 52,728 subjects eligible for inclusion, 11,953 subjects had newly diagnosed mild chronic periodontitis (MCP), and 40,775 subjects had newly diagnosed severe chronic periodontitis (SCP). Two 1:1 propensity score matched cohorts were created with 8,624 patients each in the MCP and SCP groups. To analyze the risk of dementia, a Cox proportional-hazard model was used to calculate hazard ratios with 95% confidence intervals (CIs).
RESULTS:
In the Kaplan-Meier curve, the disease-free probability was significantly lower in the SCP group than in the MCP group (p for log-rank=0.001). In the multivariable-adjusted model, the HR for the occurrence of dementia in the SCP group compared to the MCP group was 1.15 (95% CI, 1.04 to 1.27; p=0.009). A subgroup analysis revealed a significant association between dementia and the severity of periodontitis, especially in subjects who were male, aged ≥70 years, and had comorbidities.
CONCLUSIONS:
Reducing the severity of chronic periodontitis can help to reduce the risk of dementia. Therefore, it is necessary to aggressively conduct early dementia-prevention programs for males under the age of 70 that include dental health to prevent the progression of periodontitis from mild to severe.

Abstract: OBJECTIVES:
Job strain is positively associated with incident hypertension, while increasing leisure-time physical activity (LTPA) can reduce incident hypertension. However, the joint associations of job strain and LTPA with incident hypertension among United States workers have yet to be investigated. This study examined the independent and joint associations of job strain and LTPA with incident hypertension.
METHODS:
This prospective cohort study (n=1,160) utilized data from the population-based Midlife in the United States study. The associations of job strain and LTPA at baseline with incident hypertension during follow-up were examined using Cox proportional hazards models. High job strain was derived from a combination of high job demands and low job control, and high LTPA was defined as engagement in moderate or vigorous LTPA at least once per week.
RESULTS:
During 9,218 person-years of follow-up, the hypertension incidence rate was 30.6 (95% confidence interval [CI], 27.3 to 34.3) per 1,000 person-years. High job strain was associated with a higher risk for hypertension than low job strain (adjusted hazard ratio [aHR], 1.29; 95% CI, 1.00 to 1.67). High LTPA was associated with lower hypertension risk than low LTPA (aHR, 0.77; 95% CI, 0.60 to 0.98). Hypertension risk was higher among workers with high job strain and low LTPA than among those with low job strain and high LTPA (aHR, 1.70; 95% CI, 1.18 to 2.43).
CONCLUSIONS:
Job strain and LTPA showed positive and inverse associations, respectively, with incident hypertension. The combination of high job strain and low LTPA was associated with the highest risk for hypertension.

Original Article Trends and disparities in avoidable, treatable, and preventable mortalities in South Korea, 2001-2020: comparison of capital and non-capital areas

Sang Jun Eun Epidemiol Health. 2022;44:e2022067.

COVID-19: Epidemiologic Investigation Analysis of the on-ship transmission of the COVID-19 mass outbreak on the Republic of Korea Navy amphibious warfare ship

Soo Hyeon Cho, Young-Man Kim, Gyeongyong Seong, Sunkyun Park, et al. Epidemiol Health. 2022;44:e2022065.

Abstract: OBJECTIVES:
This study aimed to describe the regional avoidable mortality trends in Korea and examine the trends in avoidable mortality disparities between the Seoul Capital Area and non-Seoul-Capital areas, thereby exploring the underlying reasons for the trend changes.
METHODS:
Age-standardized mortality rates from avoidable causes between 2001-2020 were calculated by region. Regional disparities in avoidable mortality were quantified on both absolute and relative scales. Trends and disparities in avoidable mortality were analyzed using joinpoint regression models.
RESULTS:
Avoidable, treatable, and preventable mortalities in Korea decreased at different rates over time by region. The largest decreases were in the non-Seoul-Capital non-metropolitan area for avoidable and preventable mortality rates and the non-Seoul- Capital metropolitan area for treatable mortality rates, despite the largest decline being in the Seoul Capital Area prior to around 2009. Absolute and relative regional disparities in avoidable and preventable mortalities generally decreased. Relative disparities in treatable mortality between areas widened. Regional disparities in all types of mortalities tended to improve after around 2009, especially among males. In females, disparities in avoidable, treatable, and preventable mortalities between areas improved less or even worsened.
CONCLUSIONS:
Trends and disparities in avoidable mortality across areas in Korea seem to have varied under the influence of diverse social changes. Enhancing health services to underserved areas and strengthening gender-oriented policies are needed to reduce regional disparities in avoidable mortality.

Abstract: OBJECTIVES:
This investigation was conducted to determine the size and pattern, source, and transmission route of the coronavirus disease 2019 (COVID-19) outbreak on the Republic of Korea Navy (ROKN) amphibious warfare ship.
METHODS:
We investigated the characteristics of all crew members and tracked the medical records of the confirmed cases. Fourteen essential ship operation personnel were interviewed. The study design was a retrospective cohort study, and the incidence rate ratio was through a statistical program.
RESULTS:
The COVID-19 incidence on the ROKN amphibious warfare ship was 44.7% (38/85). It was estimated that the main propagation route started from the 1st floor worker, which spread to the same floor, and then to other floors. In the case of the working area, the incidence rate of crew members below the 1st floor without ventilation was higher than those on the 2nd or higher floors with natural ventilation.
CONCLUSIONS:
This case is the first case of a COVID-19 outbreak on the ROKN amphibious warfare ship, and it is estimated that the incidence rate is high because of the closed and dense environment. To prevent the spread of various respiratory diseases including COVID-19, unified mitigation such as vaccination, observing personal quarantine rules, periodic ventilation, preemptive testing, and blocking transmission through prompt contact management is necessary.

Original Article Positive association of unhealthy plant-based diets with the incidence of abdominal obesity in Korea: a comparison of baseline, most recent, and cumulative average diets

Sukyoung Jung, Sohyun Park Epidemiol Health. 2022;44:e2022063.

Original Article The influence of the dietary intake of vitamin C and vitamin E on the risk of gastric intestinal metaplasia in a cohort of Koreans

Sung Keun Park, Yeongu Chung, Chang-Mo Oh, Jae-Hong Ryoo, et al. Epidemiol Health. 2022;44:e2022062.

Abstract: OBJECTIVES:
Different approaches for analyzing repeated dietary measurements may yield differences in the magnitude and interpretation of findings. We aimed to compare 3 dietary measurements (baseline, most recent, and cumulative average) in terms of the association between plant-based diet indices (PDIs) and incident abdominal obesity in Korean adults aged 40-69 years.
METHODS:
This study included 6,054 participants (54% women) free of abdominal obesity (defined as waist circumference ≥90 cm for men and ≥85 cm for women) at baseline. As exposures, baseline, most recent, and cumulative average measurements for PDI, healthy-PDI (hPDI), and unhealthy-PDI (uPDI) were created. A Cox proportional-hazard model was used to estimate the hazard ratios (HRs) for abdominal obesity.
RESULTS:
During 45,818 person-years of follow-up (median, 9 years), we identified 1,778 incident cases of abdominal obesity. In the multivariable-adjusted analysis, a higher uPDI was associated with a higher risk of abdominal obesity in both total and stratified analyses. The findings were consistent across all approaches (Q5 vs. Q1: HRbaseline=1.70; 95% confidence interval [CI], 1.46 to 1.98; HRmost recent=1.52; 95% CI, 1.30 to 1.78; HRcumulative average=1.76; 95% CI, 1.51 to 2.06 in the total set). PDI showed no meaningful association with abdominal obesity risk in any analyses. hPDIaverage had a suggestive inverse association with abdominal obesity risk in men, and hPDIbaseline had a positive association with abdominal obesity risk in women.
CONCLUSIONS:
Greater adherence to unhealthy plant-based diets may increase the risk of developing abdominal obesity in Korean adults. The findings were generally consistent across all approaches.

Abstract: OBJECTIVES:
Studies have suggested that the dietary intake of antioxidant vitamins, such as vitamin C and vitamin E, has a potential role in inhibiting gastric carcinogenesis. The present study investigated the effect of antioxidant vitamins on the incidence of gastric intestinal metaplasia (GIM).
METHODS:
This study included 67,657 Koreans free of GIM who periodically underwent health check-ups. Dietary intake was assessed by a semiquantitative food frequency questionnaire based on the Korean National Health and Nutrition Examination Survey. Participants were categorized into 4 groups by quartiles of dietary vitamin C and vitamin E intake. The Cox proportional hazard assumption was used to determine the multivariable hazard ratio (HR) and 95% confidence interval (95% CI) for GIM.
RESULTS:
The third and fourth quartiles of vitamin C intake had a lower risk of GIM than the first quartile (multivariable-adjusted HR, 0.95; 95% CI, 0.88 to 1.03 in the second quartile, HR, 0.88; 95% CI, 0.81 to 0.97 in the third quartile, and HR, 0.85; 95% CI, 0.76 to 0.95 in the fourth quartile). Vitamin E intake greater than the second quartile level was significantly associated with a lower risk of GIM than the first quartile (multivariable-adjusted HR, 0.90; 95% CI, 0.82 to 0.97 in the second quartile, HR, 0.90; 95% CI, 0.82 to 0.99 in the third quartile, and HR, 0.83; 95% CI, 0.74 to 0.94 in the fourth quartile). This association was observed only in the subgroup analysis for men.
CONCLUSIONS:
Higher dietary intake of vitamin C and vitamin E was associated with a lower risk of GIM.

COVID-19: Original Article Predictors of COVID-19 booster vaccine hesitancy among fully vaccinated adults in Korea: a nationwide cross-sectional survey

Yunha Noh, Ju Hwan Kim, Dongwon Yoon, Young June Choe, et al. Epidemiol Health. 2022;44:e2022061.

Original Article The probability of diagnostic delays for tuberculosis and its associated risk factors in northwest Iran from 2005 to 2016: a survival analysis using tuberculosis surveillance data

Reza Ebrahimoghli, Hassan Ghobadi, Davoud Adham, Parviz Jangi, et al. Epidemiol Health. 2022;44:e2022060.

Abstract: OBJECTIVES:
This study explored predictors of coronavirus disease 2019 (COVID-19) booster hesitancy among fully vaccinated young adults and parental COVID-19 vaccine hesitancy for their children.
METHODS:
This cross-sectional study administered an online survey from December 2 to December 20, 2021. We enrolled participants aged 18-49 years, for whom ≥2 weeks had passed after their initial COVID-19 vaccination. We estimated odds ratios (ORs) with 95% confidence intervals (CIs) using multivariate logistic regression to evaluate factors associated with booster/vaccine hesitancy.
RESULTS:
Among the 2,993 participants, 48.8% showed hesitancy (wait and see: 40.2%; definitely not: 8.7%). Booster hesitancy was more common among women (OR, 1.25; 95% CI, 1.05 to 1.50), younger people (OR, 1.44; 95% CI, 1.17 to 1.77), those with a lower education level (OR, 2.05; 95% CI, 1.10 to 3.82), those who received the mRNA-1273 vaccine type (OR, 2.01; 95% CI, 1.65 to 2.45), and those who experienced serious adverse events following previous COVID-19 vaccination (OR, 2.03; 95% CI, 1.47 to 2.80). The main reasons for booster hesitancy were concerns about safety (54.1%) and doubts about efficacy (29.8%). Among the 1,020 respondents with children aged <18 years, 65.8% were hesitant to vaccinate their children against COVID-19; hesitancy was associated with younger parental age, education level, the type of vaccine the parent received, and a history of COVID-19 infection.
CONCLUSIONS:
Concerns about the efficacy and safety of COVID-19 vaccines were the major barrier to booster acceptance. The initial COVID-19 vaccine type (mRNA-1273), young age, gender (women), a low education level, and adverse events after the first COVID-19 vaccine were key predictors of booster hesitancy.

Abstract: OBJECTIVES:
Early diagnosis is essential for effective tuberculosis (TB) control programs. Therefore, this study examined the risk of delays in TB diagnosis and associated factors in Ardabil Province in northwest Iran from 2005 to 2016.
METHODS:
This longitudinal retrospective cohort study was conducted using data obtained from the Iranian National Tuberculosis Control Program at the provincial level between 2005 and 2016. The total delay in diagnosis was defined as the time interval (days) between the onset of symptoms and TB diagnosis. Survival analysis was conducted to analyze the delay in diagnosis. Associated factors were identified using a Cox proportional hazards model.
RESULTS:
A total of 1,367 new TB cases were identified. The 12-year median diagnostic delay was 45 days (interquartile range [IQR], 30-87). The annual median diagnostic delay decreased from 68 days (IQR, 33-131) in 2005 to 31 days (IQR, 30-62) in 2016. The probability of a delay in TB diagnosis decreased by 5.0% each year (hazard ratio [HR], 1.05; 95% confidence interval [CI], 1.04 to 1.07). Residence in a non-capital county (HR, 0.83; 95% CI, 0.74 to 0.92) and referral from the private health system (HR, 0.74%; 95% CI, 0.65 to 0.84) were significantly associated with an increased risk of delay in TB diagnosis over the 12-year study period.
CONCLUSIONS:
The median delay decreased during the study period. We identified factors associated with a longer delay in TB diagnosis. These findings may be useful for further TB control plans and policies in Iran.

Original Article The association between the socioeconomic deprivation level and ischemic heart disease mortality in Japan: an analysis using municipality-specific data

Tasuku Okui, Tetsuya Matoba, Naoki Nakashima Epidemiol Health. 2022;44:e2022059.

Systematic Review The prevalence of functional disability and its impact on older adults in the ASEAN region: a systematic review and meta-analysis

Phei Nie Yau, Clairen Jia Ern Foo, Nicholas Li Jie Cheah, Kar Foong Tang, et al. Epidemiol Health. 2022;44:e2022058.

Abstract: OBJECTIVES:
Geographical variation in the standardized mortality ratio (SMR) for ischemic heart disease (IHD) among municipalities has not been assessed in Japan. Additionally, associations between area-level socioeconomic deprivation indices and IHD mortality have not been identified in Japan. The present study investigated this association.
METHODS:
Information on IHD mortality was extracted from Vital Statistics data from 2018 to 2020 for each municipality in Japan. The socioeconomic deprivation level was derived from multiple socioeconomic characteristics. We classified municipalities into quintiles based on the deprivation level and investigated the association between the deprivation level and the SMR of IHD. Additionally, a Bayesian spatial regression model was used to investigate this association, adjusting for other municipal characteristics.
RESULTS:
Geographical variation in the SMR of IHD was revealed, and municipalities with high SMRs were spatially clustered. There was a weak negative correlation between the socioeconomic deprivation level and the SMRs (correlation coefficient, -0.057 for men and -0.091 for women). In contrast, the regression analysis showed a statistically significant positive association between deprived areas and the IHD mortality rate, and the relative risks for the most deprived municipalities compared with the least deprived municipalities were 1.184 (95% credible interval [CrI], 1.110 to 1.277) and 1.138 (95% CrI, 1.048 to 1.249) for men and women, respectively.
CONCLUSIONS:
A weak negative correlation between the socioeconomic deprivation level and the SMR was observed in the descriptive analysis, while the regression analysis showed that living in deprived areas was statistically positively associated with the IHD mortality rate.

Abstract: OBJECTIVES:
Functional disability is a common consequence of the ageing process and can lead to poor health outcomes due to the inability to perform activities of daily living (ADL) and instrumental activities of daily living (IADL) independently. However, the prevalence of functional disability among older adults in the Association of Southeast Asian Nations (ASEAN) region is poorly documented. This study aimed to assess the prevalence of functional disability and its impact on older adults in the ASEAN region.
METHODS:
A systematic literature search was performed on 4 databases from inception until March 2021 to identify studies examining individuals aged 60 years and above reporting functional disabilities in the ASEAN region. Information on the prevalence and impact of functional disability was extracted, assessed for bias, summarised, and analysed using a random-effects meta-analysis.
RESULTS:
Thirty-four studies with 59,944 participants were included. The pooled prevalence of ADL disability was 21.5% (95% confidence interval [CI], 16.2 to 27.3) and that of IADL disability was 46.8% (95% CI, 35.5 to 58.3). Subgroup analyses showed higher prevalence among those of advanced age and women. Adverse impacts included increased years of life with disability and poor health-related quality of life.
CONCLUSIONS:
Nearly a quarter of the older adult population in the ASEAN region experience functional disability. These findings highlight the need for further research on the burden and impact of functional disability within this region to allow decision-makers to gauge the severity of the issue, develop policies to reduce the risk of developing functional disabilities, and foster healthy ageing.

Review Epidemiology of myocardial infarction in Korea: hospitalization incidence, prevalence, and mortality

Rock Bum Kim, Jang-Rak Kim, Jin Yong Hwang Epidemiol Health. 2022;44:e2022057.

COVID-19: Original Article Maternal vaccine hesitancy towards COVID-19 immunisation of children in Qatar: a population-based cross-sectional study

Shuja Reagu, Suruchi Mohan, Johnny Awwad, Majid Alabdulla Epidemiol Health. 2022;44:e2022056.

Abstract: Few studies have comprehensively presented epidemiological indicators of myocardial infarction in Korea. However, multiple published articles and open-source secondary data on the epidemiology of myocardial infarction are now available. This review summarized the hospitalization incidence, prevalence, and mortality rate of myocardial infarction in Korea using articles and open-source data from the Health Insurance Service and the Department of Statistics, surveys of sample populations, registries of patients, and other sources. The epidemiological indicators of myocardial infarction were compared between Korea and other high-income countries. The incidence of hospitalization due to myocardial infarction in Korea was 43.2 cases per 100,000 population in 2016 and has consistently increased since 2011. It was 2.4 times higher among men than among women. The estimated prevalence among adults over 30 years of age ranged from 0.34% to 0.70% in 2020; it was higher among men and increased with age. The mortality in 2020, which was 19.3 per 100,000 population in 2020, remained relatively stable in recent years. Mortality was higher among men than among women. Based on representative inpatient registry data, the proportion of ST-elevated myocardial infarction decreased until recently, and the median time from symptom onset to hospital arrival was approximately 2 hours and 30 minutes. The hospitalization incidence, prevalence, and mortality rate of myocardial infarction were lower in Korea than in other countries, although there was an increasing trend. Comprehensive national-level support and surveillance systems are needed to routinely collect accurate epidemiological indicators.

Abstract: OBJECTIVES:
This study was conducted in Qatar to explore beliefs and attitudes among mothers towards coronavirus disease 2019 (COVID-19) vaccination for their children and to understand major factors influencing vaccine hesitancy among these mothers.
METHODS:
A population-based, online cross-sectional survey was conducted between 15 October and 15 November 2020. A composite questionnaire incorporating a validated vaccine hesitancy tool was developed and administered in both English and Arabic. Approval was obtained from the local ethics committee. Participation was voluntary and offered to all adult residents of Qatar through an online link available on social media platforms and local news portals. Only adult respondents who self-identified as mothers were included in the present study. No personal identifying data were collected.
RESULTS:
Of the mothers surveyed, 29.4% exhibited COVID-19 vaccine hesitancy regarding their children. This exceeded these mothers’ rate of personal vaccine hesitancy (27.5%). Hesitancy rates varied significantly with ethnicity, with the highest among Qatari mothers (51.3%). Intention to vaccinate children did not differ significantly between mothers who accepted the vaccine for themselves and those who did not. Overall, the main reported concerns related to long-term vaccine safety. To a significant extent, mothers relied most on self-directed research on vaccine safety for decision-making.
CONCLUSIONS:
The rate of maternal COVID-19 vaccine hesitancy exceeded both those mothers’ rate of personal vaccine hesitancy and the hesitancy rate in the general population. The intention to vaccinate children was independent of maternal vaccination history. Factors influencing maternal vaccine hesitancy differ from those influencing personal hesitancy and require an informed public health response.

Original Article The risk of stroke according to statin medication compliance in older people with chronic periodontitis: an analysis using the Korea National Health Insurance Service-Senior Cohort Database

Seon-Rye Kim, Minkook Son, Yu-Rin Kim Epidemiol Health. 2022;44:e2022055.

Original Article Blood lipid levels and all-cause mortality in older adults: the Chinese Longitudinal Healthy Longevity Survey 2008-2018

Rongxi Wang, Xiaoyue Yu, Zhiqiang Wang, Yujie Liu, et al. Epidemiol Health. 2022;44:e2022054.

Abstract: OBJECTIVES:
We investigated the risk of stroke according to statin medication compliance in older people with chronic periodontitis.
METHODS:
Chronic periodontitis patients were extracted from the National Health Insurance Service-Senior Cohort Database from 2002 to 2014. Among 255,056 chronic periodontitis patients, 41,412 patients with statin prescriptions for 28 days or more were included. The study population was divided into the top 25% of medication compliance group (TSG) and the lower 25% of medication compliance group (BSG). After 1:1 propensity score matching was performed, the final number of patients in the BSG and TSG was 6,172 each. To analyze the risk of stroke, a Cox proportional hazard model was performed to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) after adjusting for age, sex, income level, hypertension, diabetes, and Charlson comorbidity index.
RESULTS:
In the Kaplan-Meier curve, the disease-free probability was prominently lower in the BSG than in the TSG (p for log-rank= 0.001). The HR in the multivariable-adjusted model for stroke occurrence in the TSG compared to the BSG was 0.79 (95% CI, 0.67 to 0.92; p= 0.002). Subgroup analyses showed significant associations between compliance to statin medication and stroke, especially in female, people 85 years or older, and patients with comorbidities.
CONCLUSIONS:
Increasing compliance to statins may reduce stroke risk in older adults with chronic periodontitis. Therefore, in order to increase medication compliance among older people with chronic periodontitis, it is necessary for medical staff to make efforts to provide effective medication guidance.

Abstract: OBJECTIVES:
Proper blood lipid levels are essential for survival in older adults, but inconsistent relationships have been reported between blood lipids and all-cause mortality in the elderly.
METHODS:
This retrospective longitudinal study analyzed data from 1,067 Chinese older adults enrolled in the Chinese Longitudinal Healthy Longevity Survey collected in 2008 and followed up until death or December 31, 2018. The outcome was all-cause mortality. Multivariate Cox regression analyses were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) with stratification by age (60-80, 80-100, or ≥100 years) for further analysis. The survival probability according to lipid profile quartiles was calculated using Kaplan-Meier curves and the log-rank test.
RESULTS:
The participants’ mean age was 84.84 years, and 57.0% were female. In total, 578 individuals died, and 277 were lost to follow-up. The mean total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were higher among those who died than among those who survived. Participants in the second HDL-C quartile and the highest LDL-C and triglyceride (TG) quartiles had 28% higher, 23% lower, and 49% lower risks of all-cause mortality, respectively. After further adjustment, the associations remained except for HDL-C, and additional associations were observed between all-cause mortality and the third TC and LDL-C quartiles and the second TG quartile (HR, 1.44; 95% CI, 1.01 to 2.06; HR, 0.68; 95% CI, 0.49 to 0.94; HR, 0.79; 95% CI, 0.62 to 0.99, respectively).
CONCLUSIONS:
Older adults should maintain an LDL-C level of 1.91-2.47 mmol/L and a TG level of no less than 1.66 mmol/L.

COVID-19: Original Article The impact of COVID-19 on screening for colorectal, gastric, breast, and cervical cancer in Korea

Hyeree Park, Seung Hee Seo, Jong Heon Park, Shin Hye Yoo, et al. Epidemiol Health. 2022;44:e2022053.

Original Article Effect modification of consecutive high concentration days on the association between fine particulate matter and mortality: a multi-city study in Korea

Hyungryul Lim, Sanghyuk Bae, Jonghyuk Choi, Kyung-Hwa Choi, et al. Epidemiol Health. 2022;44:e2022052.

Abstract: OBJECTIVES:
The coronavirus disease 2019 (COVID-19) pandemic has affected the utilization of healthcare services, including participation in cancer screening programs. We compared cancer screening participation rates for colorectal, gastric, breast, and cervical cancers among participants in the National Cancer Screening Program (NCSP) in 2019 and 2020 to address the potential distraction effect of COVID-19 on cancer screening.
METHODS:
Data from the NCSP for 4 cancer types (stomach, colorectal, breast, and cervical) in 2019 and 2020 were used to calculate cancer screening participation rates by calendar month, gender, age group, and geographical region. Monthly participation rates were analyzed per 1,000 eligible individuals.
RESULTS:
The screening participation rate decreased in 2020 compared to 2019 for all 4 cancers: colorectal (40.5 vs. 35.3%), gastric (61.9 vs. 54.6%), breast (63.8 vs. 55.8%), and cervical (57.8 vs. 52.2%) cancers. Following 2 major COVID-19 waves in March and December 2020, the participation rates in the 4 types of cancer screening dropped compared with those in 2019. The highest decline was observed in the elderly population aged 80 years and older (percentage change: -21% for colorectal cancer; -20% for gastric cancer; -26% for breast cancer; -20% for cervical cancer).
CONCLUSIONS:
After the 2 major COVID-19 waves, the screening participation rate for 4 types of cancer declined compared with 2019. Further studies are needed to identify the indirect effects of the COVID-19 pandemic on cancer patients, such as delayed diagnoses of cancer or excess cancer deaths.

Abstract: OBJECTIVES:
Although there is substantial evidence for the short-term effect of fine particulate matter (PM_2.5) on daily mortality, few epidemiological studies have explored the effect of prolonged continuous exposure to high concentrations of PM_2.5. This study investigated how the magnitude of the mortality effect of PM_2.5 exposure is modified by persistent exposure to high PM_2.5 concentrations.
METHODS:
We analyzed data on the daily mortality count, simulated daily PM_2.5 level, mean daily temperature, and relative humidity level from 7 metropolitan cities from 2006 to 2019. Generalized additive models (GAMs) with quasi-Poisson distribution and random-effects meta-analyses were used to pool city-specific effects. To investigate the effect modification of continuous exposure to prolonged high concentrations, we applied categorical consecutive-day variables to the GAMs as effect modification terms for PM_2.5.
RESULTS:
The mortality risk increased by 0.33% (95% confidence interval [CI], 0.16 to 0.50), 0.47% (95% CI, -0.09 to 1.04), and 0.26% (95% CI, -0.08 to 0.60) for all-cause, respiratory, and cardiovascular diseases, respectively, with a 10 μg/m3 increase in PM_2.5 concentration. The risk of all-cause mortality per 10 μg/m3 increase in PM_2.5 on the first and fourth consecutive days significantly increased by 0.63% (95% CI, 0.20 to 1.06) and 0.36% (95% CI, 0.01 to 0.70), respectively.
CONCLUSIONS:
We found increased risks of all-cause, respiratory, and cardiovascular mortality related to daily PM_2.5 exposure on the day when exposure to high PM_2.5 concentrations began and when exposure persisted for more than 4 days with concentrations of ≥35 μg/m3. Persistently high PM_2.5 exposure had a stronger effect on seniors.

COVID-19: Original Article Changes in cancer screening before and during COVID‐19: findings from the Korean National Cancer Screening Survey 2019 and 2020

Thao Thi Kim Trinh, Yun Yeong Lee, Mina Suh, Jae Kwan Jun, et al. Epidemiol Health. 2022;44:e2022051.

Systemic Review The relationship between metabolic syndrome and its components with bladder cancer: a systematic review and meta-analysis of cohort studies

Mozhgan Ahmadinezhad, Maedeh Arshadi, Elahe Hesari, Maedeh Sharafoddin, et al. Epidemiol Health. 2022;44:e2022050.

Abstract: OBJECTIVES:
The coronavirus disease 2019 (COVID-19) pandemic has negatively affected every aspect of medical care. However, information regarding the impact of the pandemic on cancer screening is lacking. This study aimed to explore cancer screening changes by geographic region before and during the pandemic in Korea.
METHODS:
Korean National Cancer Screening Survey data for 2019 and 2020 were used. Changes in the screening rate before and during the COVID-19 pandemic were calculated by subtracting the rate in 2020 from the rate in 2019. Multivariate logistic regression analyses examined the differences in screening rates at the national and 16 provincial levels before and after the COVID-19 outbreak.
RESULTS:
The 1-year screening rates for the four types of cancer decreased during the pandemic (stomach cancer: -5.1, colorectal cancer: -3.8, breast cancer: -2.5, cervical cancer: -1.5%p). In metropolitan areas, the odds of undergoing screening tests during the pandemic were significantly lower than before the pandemic for stomach (adjusted odds ratio [aOR], 0.66; 95% confidence interval [CI], 0.56 to 0.76), colorectal (aOR, 0.63; 95% CI, 0.50 to 0.79), and breast cancers (aOR, 0.75; 95% CI, 0.60 to 0.94). Furthermore, the likelihood of undergoing stomach cancer screening during the pandemic was significantly lower than before the pandemic in non-metropolitan urban areas (aOR, 0.81; 95% CI, 0.70 to 0.94), while it was higher in rural areas (aOR, 1.54; 95% CI, 1.10 to 2.16).
CONCLUSIONS:
Since the COVID-19 pandemic, the cancer screening rate has decreased significantly, especially in large cities. Public health efforts are required to improve cancer screening rates.

Abstract: A previous meta-analysis, entitled “The association between metabolic syndrome and bladder cancer susceptibility and prognosis: an updated comprehensive evidence synthesis of 95 observational studies involving 97,795,299 subjects,” focused on all observational studies, whereas in the present meta-analysis, we focused on cohort studies to obtain more accurate and stronger evidence to evaluate the association between metabolic syndrome and its components with bladder cancer. PubMed, Embase, Scopus, and Web of Science were searched to identify studies on the association between metabolic syndrome and its components with bladder cancer from January 1, 2000 through May 23, 2021. The pooled relative risk (RR) and 95% confidence intervals (CI) were used to measure this relationship using a random-effects meta-analytic model. Quality appraisal was undertaken using the Newcastle-Ottawa Scale. In total, 56 studies were included. A statistically significant relationship was found between metabolic syndrome and bladder cancer 1.09 (95% CI, 1.02 to 1.17), and there was evidence of moderate heterogeneity among these studies. Our findings also indicated statistically significant relationships between diabetes (RR, 1.23; 95% CI, 1.16 to 1.31) and hypertension (RR, 1.07; 95% CI, 1.01 to 1.13) with bladder cancer, but obesity and overweight did not present a statistically significant relationship with bladder cancer. We found no evidence of publication bias. Our analysis demonstrated statistically significant relationships between metabolic syndrome and the risk of bladder cancer. Furthermore, diabetes and hypertension were associated with the risk of bladder cancer.

Original Article Gender differences in the association between multimorbidity and depression in older Korean adults: an analysis of data from the National Survey of Older Koreans (2011-2017)

SeoYeon Hwang, Jin Young Nam, Jeong Hyun Ahn, Soojin Park Epidemiol Health. 2022;44:e2022049.

Epidemiologic Investigation Investigation of a human brucellosis outbreak in Douz, Tunisia, 2018

Nejib Charaa, Rabaa Ghrab, Aicha Ben Othman, Mohamed Makhlouf, et al. Epidemiol Health. 2022;44:e2022048.

Abstract: OBJECTIVES:
Previous studies have shown that people with multimorbidity have a higher risk of depression than those without multimorbidity. However, few studies have examined the association between depression and multimorbidity in men and women separately. Since the rates of depression and multimorbidity are different in men and women, it is necessary to examine whether gender differences affect their association.
METHODS:
This study included 30,138 participants (aged ≥ 65 years) from the National Survey of Older Koreans (2011-2017). Depression was defined using the Korean version of the Geriatric Depression Scale (SGDS-K). Multimorbidity was defined as people who had 2 or more chronic diseases, including arthritis, diabetes, heart disease, hypertension, pulmonary disease, cancer, stroke, or osteoporosis. Multiple logistic regression analysis was performed to determine the association between depression and multimorbidity.
RESULTS:
In total, 22.2% and 30.7% of men and women, respectively, had depression. Those with multimorbidity had a higher risk of depression than those without chronic conditions; specifically, the difference in risk among men was greater than that among women. Age was considered a moderator for women. While the effects of pulmonary disease, stroke, and cancer were especially substantial in the integrated analysis, gender differences were observed related to various chronic conditions comorbid with heart disease.
CONCLUSIONS:
There are gender differences in the association between multimorbidity and depression among older Korean adults. Therefore, gender-specific care should be provided to reduce depression in older adults with multimorbidity.

Abstract: OBJECTIVES:
In 2017, the incidence of human brucellosis in Tunisia was 9.8 per 100,000 population. In the Douz district, 2 cases were reported in March 2018. Prior to that date, the last indigenous cases to be reported in Douz had been in 2015. This study aimed to identify the source of this new contamination and recommend control interventions.
METHODS:
This case-control study included residents of Douz who presented with clinical symptoms of brucellosis and had a subsequent Wright test antibody titer ≥ 1/160. The controls were neighbors of the infected cases who had a negative Rose Bengal test. Univariate and multivariate analyses were performed to estimate the odds ratios of risk factors. Goats belonging to the cases and controls were actively screened.
RESULTS:
Twenty-five infected cases and 52 uninfected controls were enrolled. All infected cases had consumed goat milk and 92% had purchased it from the same breeder. Consumption of goat milk from this breeder (adjusted odds ratio [aOR], 30.78; 95% confidence interval [CI], 6.47 to 235.91) and overall consumption of raw goat milk (aOR, 14.84; 95% CI, 2.04 to 310.44) were independent risk factors for brucellosis. The breeder had 18 goats, 5 of which were smuggled from a neighboring country. Three of those goats were diagnosed with brucellosis.
CONCLUSIONS:
Consumption of raw milk from smuggled sick goats was the main risk factor in this outbreak. The sick goats were slaughtered and an education campaign was conducted. Vaccination, control of cross-border animal movements, and control of goat milk sales must be strengthened to prevent the spread of brucellosis in southwestern Tunisia.

Original Article Epidemiological data on nutritional disorders and outcomes in hospitalized Thai children: an analysis of data from the National Health Database 2015-2019

Suchaorn Saengnipanthkul, Jeeraparn Phosuwattanakul, Kaewjai Thepsuthammarat, Nalinee Chongviriyaphan Epidemiol Health. 2022;44:e2022047.

Original Article Non-linear association between serum folate concentrations and dyslipidemia: Korea National Health and Nutrition Examination Survey 2016-2018

Taiyue Jin, Eun Young Park, Byungmi Kim, Jin-Kyoung Oh Epidemiol Health. 2022;44:e2022046.

Abstract: OBJECTIVES:
Malnutrition in hospitalized patients is a frequently overlooked health issue. We aimed to assess the prevalence and pattern of nutritional disorders in hospitalized Thai children from the National Health Database.
METHODS:
Hospitalized children aged 1 month to 18 years diagnosed with nutritional disorders between 2015 and 2019 were retrospectively reviewed using the National Health Security Office data. Based on the International Classification of Diseases, 10th revision, Clinical Modification, nutritional disorders were classified into 3 major forms of malnutrition: undernutrition (E40-E46), overweight and obesity (E66), and micronutrient deficiencies (D50-D53, E50-E56, E58, E60-E61, and E63).
RESULTS:
Out of 5,188,033 hospitalized children, malnutrition was identified in 115,254 (2.2%). Protein-energy malnutrition (PEM), overweight and obesity, and micronutrient deficiencies were prevalent in 0.21%, 0.27%, and 1.81%, respectively. Among those with micronutrient deficiencies, 95.0% had iron deficiency anemia, 2.2% had vitamin D deficiency, and 0.7% had zinc deficiency. Children aged under 5 years mostly had PEM, followed by iron deficiency anemia. Teenagers commonly had obesity and vitamin D deficiency. Patients with PEM who were admitted with common diseases had significantly longer hospital stays and higher hospital costs and mortality rates than those without PEM.
CONCLUSIONS:
Hospitalized children had various nutritional disorders, particularly PEM, which was associated with higher morbidity and mortality. Nutritional screening tools should be utilized for the early detection and treatment of malnutrition. Specific International Classification of Diseases codes for nutritional care services and intervention should be available. Additionally, nutritional interventions should be reimbursed, along with nutritional education and empowerment of healthcare providers, to improve hospital care service and improve patient outcomes.

Abstract: OBJECTIVES:
We aimed to evaluate the association between serum folate concentrations and the prevalence of dyslipidemia.
METHODS:
A total of 4,477 adults (2,019 male and 2,458 female) enrolled in the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2018 were included. Serum samples were used to assess folate concentrations and total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol levels. Multivariate logistic regression with sampling weights was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).
RESULTS:
Elevated TC, TG, LDL-cholesterol and HDL-cholesterol levels were observed in 506 (11.3%), 646 (14.4%), 434 (9.7%), and 767 (17.1%) participants, respectively. We found non-linear trends between serum folate concentrations and the prevalence of hypercholesterolemia and hyper-LDL cholesterolemia from the restricted cubic smoothing spline. A higher prevalence of hypercholesterolemia was observed among participants in the first tertile of serum folate concentrations (OR,1.38; 95% CI, 1.05 to 1.79) than among those in the second tertile. However, a higher prevalence of hyper-LDL cholesterolemia was identified for both the first and third serum folate concentration tertiles (OR, 1.49; 95% CI, 1.08 to 2.05 and OR, 1.63; 95% CI, 1.20 to 2.20, respectively); furthermore, in these tertiles, the prevalence of hyper-LDL cholesterolemia was more pronounced among obese participants.
CONCLUSIONS:
Non-linear associations may exist between serum folate concentrations and the prevalence of hypercholesterolemia and hyper-LDL cholesterolemia in adults. The findings suggest that more accurate recommendations about folate intake and folic acid fortification and supplementation should be provided.

Original Article Spatial analysis of tuberculosis treatment outcomes in Shanghai: implications for tuberculosis control

Jing Zhang, Xin Shen, Chongguang Yang, Yue Chen, et al. Epidemiol Health. 2022;44:e2022045.

COVID-19: Original Article The impact of COVID-19 on cancer care in a tertiary hospital in Korea: possible collateral damage to emergency care

Shin Hye Yoo, Jin-Ah Sim, Jeongmi Shin, Bhumsuk Keam, et al. Epidemiol Health. 2022;44:e2022044.

Abstract: OBJECTIVES:
Tuberculosis (TB) treatment outcomes are a key indicator in the assessment of TB control programs. We aimed to identify spatial factors associated with TB treatment outcomes, and to provide additional insights into TB control from a geographical perspective.
METHODS:
We collected data from the electronic TB surveillance system in Shanghai, China and included pulmonary TB patients registered from January 1, 2009 to December 31, 2016. We examined the associations of physical accessibility to hospitals, an autoregression term, and random hospital effects with treatment outcomes in logistic regression models after adjusting for demographic, clinical, and treatment factors.
RESULTS:
Of the 53,475 pulmonary TB patients, 49,002 (91.6%) had successful treatment outcomes. The success rate increased from 89.3% in 2009 to 94.4% in 2016. The successful treatment outcome rate varied among hospitals from 78.6% to 97.8%, and there were 12 spatial clusters of poor treatment outcomes during the 8-year study period. The best-fit model incorporated spatial factors. Both the random hospital effects and autoregression terms had significant impacts on TB treatment outcomes, ranking 6th and 10th, respectively, in terms of statistical importance among 14 factors. The number of bus stations around the home was the least important variable in the model.
CONCLUSIONS:
Spatial autocorrelation and hospital effects were associated with TB treatment outcomes in Shanghai. In highly-integrated cities like Shanghai, physical accessibility was not related to treatment outcomes. Governments need to pay more attention to the mobility of patients and different success rates of treatment among hospitals.

Abstract: OBJECTIVES:
We investigated the impact of the COVID-19 pandemic on cancer care in a tertiary hospital in Korea without specific lockdown measures.
METHODS:
A retrospective cohort of cancer patients from one of the largest tertiary hospitals in Korea was used to compare healthcare utilization in different settings (outpatient cancer clinic, the emergency department [ED], and admissions to the hematology/oncology ward) between January 1 and December 31, 2020 and the same time period in 2019. The percent changes in healthcare utilization between the 2 periods were calculated.
RESULTS:
A total of 448,833 cases from the outpatient cohort, 26,781 cases from the ED cohort, and 14,513 cases from the admission cohort were reviewed for 2019 and 2020. The total number of ED visit cases significantly decreased from 2019 to 2020 by 18.04%, whereas the proportion of cancer patients remained stable. The reduction in ED visits was more prominent in patients with symptoms suspicious for COVID-19, high-acuity cases, and those who lived in non-capital city areas. There were no significant changes in the number of total visits, new cases in the outpatient clinic, or the total number of hospitalizations between the 2 periods.
CONCLUSIONS:
During the pandemic, the number of ED visits significantly decreased, while the use of the outpatient clinic and hospitalizations were not affected. Cancer patients’ ED visits decreased after the COVID-19 outbreak, suggesting the potential for collateral damage outside the hospital if patients cannot reach the ED in a timely manner.

COVID-19: Special Article Smoking, drinking, and physical activity among Korean adults before and during the COVID-19 pandemic: a special report of the 2020 Korea National Health and Nutrition Examination Survey

Sunhye Choi, Jinwook Bahk, Suyeon Park, Kyungwon Oh, et al. Epidemiol Health. 2022;44:e2022043.

COVID-19: Special Article Mental health of Korean adults before and during the COVID-19 pandemic: a special report of the 2020 Korea National Health and Nutrition Examination Survey

Hyunsuk Jeong, Suyeon Park, Jihee Kim, Kyungwon Oh, et al. Epidemiol Health. 2022;44:e2022042.

Abstract: OBJECTIVES:
This study aimed to describe trends in health behaviours between 2011 and 2020 and compare the changes in these behaviours between the 2020 COVID-19 pandemic and previous periods according to socio-demographic variables.
METHODS:
This study used data from the 2011 to 2020 Korea National Health and Nutrition Examination Survey. Current cigarette smoking, high-risk drinking, and inadequate physical activity levels were used as health behaviour indicators. The age-standardized prevalence, differences in prevalence between the periods, and the annual percentage change (APC) were calculated.
RESULTS:
Current cigarette smoking showed a decreasing trend (APC, -2.6), high-risk drinking remained unchanged, and inadequate physical activity levels increased (APC, 3.5) during 2011-2020. There were significant differences in high-risk drinking (3.1%p; 95% confidence interval [CI], 0.3 to 5.9) and inadequate physical activity levels (4.3%p; 95% CI, 0.4 to 8.1) between 2019 and 2020 in men. Among men, increased high-risk drinking was found in those aged 40-49 years, non-single households, urban residents, and the middle and highest income groups between 2019 and 2020. The low educational group and manual workers among men aged 30-59 years also showed an increased proportion of high-risk drinking. Inadequate physical activity levels also increased among men between 2019 and 2020 in those aged 30-39 years, non-single households, urban residents, and the upper-middle-income group.
CONCLUSIONS:
In the first year of the COVID-19 pandemic, Korean men’s high-risk drinking and inadequate physical activity levels increased. In addition to social efforts to reduce the spread of infectious diseases, active measures to positively change health behaviour are needed.

Abstract: OBJECTIVES:
Coronavirus disease 2019 (COVID-19) and the associated social distancing, limited freedom, and fear of an uncertain future are expected to have substantial mental health effects. We investigated mental health responses in the community during the first year of the COVID-19 pandemic in Korea.
METHODS:
We used 2016-2019 and 2020 data from the Korea National Health and Nutrition Examination Survey (KNHANES) to assess pre-pandemic and pandemic mental health status, respectively, in terms of perceived severe stress, depression, and suicidal plans. All analyses were gender-stratified. Pre-specified subgroup analyses were performed according to age, employment status, and household income.
RESULTS:
The percentage of Korean adults with suicidal plans increased significantly from 1.3%p (95% confidence interval [CI], 1.1 to 1.5) in 2016-2019 to 1.8%p (95% CI, 1.4 to 2.1) in 2020. Individuals in their 20s and 40s showed a marked increase in suicidal plans (1.2%p; 95% CI, 0.0 to 2.3 and 0.9%p; 95% CI, 0.0 to 1.8, respectively). In men, depression and perceived severe stress increased significantly from pre-COVID-19 to 2020. There was a 2.4%p (95% CI, 0.8 to 4.0) increase in depression among standard workers and a 2.9%p increase in depression in individuals in the second-highest quintile of household income from 2016 and 2018 to 2020.
CONCLUSIONS:
As COVID-19 continued, mental health issues such as suicidal plans, depression, and severe stress increased significantly in young men and people in the second-highest quintile of household income. Proactive community mental health efforts are needed to prevent increases in the suicide rate resulting from prolonged exposure to the COVID-19 pandemic.

COVID-19: Special Article Obesity, hypertension, diabetes mellitus, and hypercholesterolemia in Korean adults before and during the COVID-19 pandemic: a special report of the 2020 Korea National Health and Nutrition Examination Survey

Ga Bin Lee, Yoonjung Kim, Suyeon Park, Hyeon Chang Kim, et al. Epidemiol Health. 2022;44:e2022041.

Original Article The association of pancreatic cancer incidence with smoking status and smoking amount in Korean men

Do Jin Nam, Chang-Mo Oh, Eunhee Ha, Min-Ho Kim, et al. Epidemiol Health. 2022;44:e2022040.

Abstract: OBJECTIVES:
We investigated trends in obesity, hypertension, diabetes, and hypercholesterolemia before and during the coronavirus disease 2019 (COVID-19) pandemic in the Korean adult population.
METHODS:
Data from 60,098 participants in the Korea National Health and Nutritional Examination Survey between 2011 and 2020 aged ≥19 were used. The age-standardized prevalence and annual percent changes (APCs) were calculated for obesity (body mass index ≥25 kg/m2), hypertension (systolic/diastolic blood pressure ≥140/90 mmHg or under treatment), diabetes (hemoglobin A1c ≥6.5%, fasting glucose ≥126 mg/dL, physician diagnosis, or under treatment), and hypercholesterolemia (total cholesterol ≥240 mg/dL or under treatment).
RESULTS:
Over the past decade (2011-2020), the age-standardized APCs (95% confidence intervals) for obesity, hypertension, diabetes and hypercholesterolemia were 3.0% (2.1 to 3.8), 0.1% (-1.3 to 1.5), 1.5% (-1.0 to 4.0) and 8.0% (5.7 to 10.3), respectively, in men; and -0.2% (-1.5 to 1.2), -0.5% (-1.9 to 0.9), -0.1% (-2.3 to 2.2) and 5.9% (3.9 to 8.0), respectively, in women. In 2020 compared to the previous 3 years (2017-2019), obesity, hypertension, diabetes, and hypercholesterolemia increased in men (6.0, 1.8, 1.9, and 2.8%p, respectively), but an increase was not apparent in women (2.5, -1.1, 0.8, and 0.7%p, respectively).
CONCLUSIONS:
An increase in major chronic diseases was observed in Korean adults, especially men, during the COVID-19 pandemic. In order to reduce the burden of cardiovascular and metabolic diseases in the future, effective intervention strategies need to be developed according to the characteristics of the target groups.

Abstract: OBJECTIVES:
Our study examined the dose-response relationship between smoking amounts (pack-years) and the risk of developing pancreatic cancer in Korean men.
METHODS:
Of 125,743 participants who underwent medical health checkups in 2009, 121,408 were included in the final analysis and observed for the development of pancreatic cancer. We evaluated the associations between smoking amounts and incident pancreatic cancer in 4 groups classified by pack-year amounts. Cox proportional hazards models were used to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of incident pancreatic cancer by comparing groups 2 (<20 pack-year smokers), 3 (20-≤40 pack-year smokers), and 4 (>40 pack-year smokers) with group 1 (never smokers).
RESULTS:
During 527,974.5 person-years of follow-up, 245 incident cases of pancreatic cancer developed between 2009 and 2013. The multivariate-adjusted HRs (95% CIs) for incident pancreatic cancer in groups 2, 3, and 4 were 1.05 (0.76 to 1.45), 1.28 (0.91 to 1.80), and 1.57 (1.00 to 2.46), respectively (p for trend=0.025). The HR (95% CI) of former smokers showed a dose-response relationship in the unadjusted model, but did not show a statistically significant association in the multivariate-adjusted model. The HR (95% CI) of current smokers showed a dose-response relationship in both the unadjusted (p for trend=0.020) and multivariate-adjusted models (p for trend=0.050).
CONCLUSIONS:
The risk of developing pancreatic cancer was higher in current smokers status than in former smokers among Korean men, indicating that smoking cessation may have a protective effect.

Original Article The association between fruit and vegetable consumption and metabolic syndrome in Korean adults: does multivitamin use matter?

Jihae Kim, Li-Juan Tan, Hyein Jung, Yumi Roh, et al. Epidemiol Health. 2022;44:e2022039.

Brief Communication Occupational inequalities in mortality in Korea: an analysis using nationally representative mortality follow-up data from the late 2000s and after

Eunjeong Noh, Young-Ho Khang Epidemiol Health. 2022;44:e2022038.

Abstract: OBJECTIVES:
Metabolic syndrome (MetS) is closely associated with dietary intake; however, few studies have investigated whether the consumption of fruits and vegetables and multivitamin use affect MetS in the Korean population. This study aimed to examine these effects in Korean adults.
METHODS:
This was a cross-sectional study of 89,548 participants aged between 40 years and 69 years selected from the baseline data of the Health Examinees study conducted in Korea. Fresh vegetable and fruit consumption was assessed using a validated 106-item food frequency questionnaire. MetS and its components were defined using the National Cholesterol Education Program, Adult Treatment Panel III criteria. Multivariate logistic regression analyses were conducted to identify associations of fresh vegetable, fruit, and fresh vegetable+fruit consumption and multivitamin use with the prevalence of MetS.
RESULTS:
Female in the highest quartile of fresh vegetable, fruit, and fresh vegetable + fruit consumption exhibited a lower prevalence of MetS than those in the lowest quartile. An inverse association with the prevalence of MetS was observed among male with only fresh vegetable consumption. The interaction between the 3 categories and multivitamin intake on the prevalence of MetS was not significant (all p_interaction>0.05), regardless of sex.
CONCLUSIONS:
Multivitamin use and consumption of fresh vegetables and fruits had no significant synergistic effects. Although fresh vegetable and fruit consumption showed an inverse association with the prevalence of MetS, this relationship was not altered by multivitamin use.

Abstract: Many Korean and international studies have found higher mortality rates and poorer health conditions among manual workers than among non-manual workers. However, a recent study using unlinked data argued that since the economic crisis in Korea in the late 2000s, the mortality estimates of male Korean non-manual workers have been higher than those of manual workers. Our work using individually linked data from the late 2000s and after aimed to examine mortality inequality by occupational class. We analyzed Korea National Health and Nutrition Examination Survey data that were individually linked to cause-of-death data. Cox regression analysis was used to identify the hazard ratios for mortality by occupational class. Of 11,766 males aged between 35 and 64, 397 died between 2007 and 2018: 142 died from cancer, 68 from cardiovascular disease, 88 from external causes, and 99 from other causes. After controlling for age, the mortality estimates for manual workers were 1.85 times higher than those for upper non-manual workers (p<0.05). We observed no evidence of reversed mortality inequality among occupational classes in Korea since the 2000s; this previously reported finding might have been due to numerator-denominator bias arising from the use of unlinked data.

Cohort Profile The Asenze Cohort Study in KwaZulu-Natal, South Africa: protocol and cohort profile

Chris Desmond, Gabriella A. Norwitz, Jane D. Kvalsvig, Rachel S. Gruver, et al. Epidemiol Health. 2022;44:e2022037.

COVID-19: Brief Communication Dynamics of hospitalizations and in-hospital deaths from COVID-19 in northeast Brazil: a retrospective analysis based on the circulation of SARS-CoV-2 variants and vaccination coverage

Paulo Ricardo Martins-Filho, Adriano Antunes de Souza Araújo, Lucindo José Quintans-Júnior, Bárbara dos Santos Soares, et al. Epidemiol Health. 2022;44:e2022036.

Abstract: The Asenze cohort is set in South Africa, a middle-income country impacted by one of the highest global rates of people living with HIV/AIDS and high levels of socioeconomic inequality. This longitudinal population-based cohort of children and their primary caregivers assesses household and caregiver functioning, child health, social well-being, and neuro-development from childhood through adolescence. Almost 1,600 children born at the peak of the human immunodeficiency virus epidemic (2003-2005) were followed (with their primary caregivers) in 3 waves, between 2008 and 2021, at average ages of 5, 7, and 16. Wave 3 is currently underway, having assessed over 1,100 of the original wave 1 children. Wave 4 begins in 2022. The study, with a dyadic structure, uses a broad range of measures, validated in South Africa or recommended for global use, that address physical, social and neuro-development in childhood and adolescence, and the social, health, and psychological status of children’s primary caregivers. The Asenze study deepens our understanding of childhood physical, cognitive, and social abilities and/or disabilities, including risk-taking behaviors, and biological, environmental, and social determinants of health. We anticipate the findings will contribute to the development of community-informed interventions to promote well-being in this South African population and elsewhere.

Abstract: This study investigated the dynamics of hospitalizations and in-hospital deaths from coronavirus disease 2019 (COVID-19) throughout the pandemic in northeast Brazil, the Brazilian region with the worst socioeconomic indicators. In total, 141,445 cases, 8,213 hospital admissions, and 1,644 in-hospital deaths from COVID-19 were registered from March 14, 2020 to February 5, 2022. The overall rates of hospitalization and in-hospital deaths were 5.8% and 20.0%, respectively. The hospitalization and death rates significantly decreased over time, which may have been related to progress in vaccination. During the spread of the Gamma variant (January to June 2021), most hospitalized individuals were young adults, and approximately 40% of deaths occurred in this age group. During the predominance of Delta (July to December 2021), over 75% of deaths occurred among the elderly and unvaccinated or partially vaccinated individuals. This rate decreased to 42.3% during the transmission of the Omicron variant (January to February 2022), during which 34.6% of deaths were recorded among fully vaccinated individuals (2 doses) and 23.1% among those who received full vaccination and a booster. The Omicron-driven third wave was associated with a rise in the proportion of deaths among vaccinated individuals, especially among those who had not received a booster dose.

COVID-19: Original Article The vaccination coverage rate in under-5 children in Nasiriyah, Iraq before and during the COVID-19 pandemic

Ali Rifaat Alhaddad, Elham Ahmadnezhad, Akbar Fotouhi Epidemiol Health. 2022;44:e2022035.

COVID-19: Original Article Model-based cost-effectiveness analysis of oral antivirals against SARS-CoV-2 in Korea

Youngji Jo, Sun Bean Kim, Munkhzul Radnaabaatar, Kyungmin Huh, et al. Epidemiol Health. 2022;44:e2022034.

Abstract: providOBJECTIVES:
This study compared the vaccination coverage rate (VCR) in children under 5 years old in Nasiriyah, Iraq before and during the coronavirus disease 2019 (COVID-19) pandemic.
METHODS:
This cross-sectional study was conducted in the city of Nasiriyah in southeastern Iraq, with data collected from 79 primary healthcare facilities. This study evaluated the VCR in 3 periods (2018, 2019, and 2020) using multi-level random sampling. Pertinent data were extracted from the vaccination records of 598 children for Bacillus Calmette-Guérin (BCG); pentavalent 1, 2, and 3; measles; and activated oral poliovirus vaccine 1 and 2. Missing data were completed by telephone calls to participants’ parents. Logistic regression was applied to compare and estimate the odds ratios (ORs) with 95% confidence intervals (CIs) for the association between VCR and related factors.
RESULTS:
The data showed the greatest decline in the studied vaccines in 2020. Among the vaccines studied, BCG had the highest rate in all 3 periods (100% VCR) and measles had the lowest rate (83.7%), reaching 63.6% in 2020 (p<0.001). The highest OR among all types of vaccine were found for the pentavalent-3 vaccine among city dwellers and those born in 2020 (OR, 2.67; 95% CI, 1.39 to 5.10 and OR, 2.34; 95% CI, 1.28 to 4.28, respectively).
CONCLUSIONS:
The VCR for children decreased during the COVID-19 pandemic in Iraq, and new health policies are needed to increase the coverage rate. Improving the knowledge and attitudes of parents, as well as removing barriers or risk factors, can also be effective in improving the VCR.

Abstract: OBJECTIVES:
Many countries have authorized the emergency use of oral antiviral agents for patients with mild-to-moderate cases of coronavirus disease 2019 (COVID-19). We assessed the cost-effectiveness of these agents for reducing the number of severe COVID-19 cases and the burden on Korea’s medical system.
METHODS:
Using an existing model, we estimated the number of people who would require hospital/intensive care unit (ICU) admission in Korea in 2022. The treatment scenarios included (1) all adult patients, (2) elderly patients only, and (3) adult patients with underlying diseases only, compared to standard care. Based on the current health system capacity, we calculated the incremental costs per severe case averted and hospital admission for each scenario.
RESULTS:
We estimated that 236,510 COVID-19 patients would require hospital/ICU admission in 2022 with standard care only. Nirmatrelvir/ritonavir (87% efficacy) was predicted to reduce this number by 80%, 24%, and 17% when targeting all adults, adults with underlying diseases, and elderly patients (25, 8, and 4%, respectively, for molnupiravir, with 30% efficacy). Nirmatrelvir/ritonavir use is likely to be cost-effective, with predicted costs of US$8,878, US$8,964, and US$1,454, per severe patient averted for the target groups listed above, respectively, while molnupiravir is likely to be less cost-effective, with costs of US$28,492, US$29,575, and US$7,915, respectively.
CONCLUSIONS:
In Korea, oral treatment using nirmatrelvir/ritonavir for symptomatic COVID-19 patients targeting elderly patients would be highly cost-effective and would substantially reduce the demand for hospital admission to below the capacity of the health system if targeted to all adult patients instead of standard care.

Original Article Association between dietary and suicidal behaviors in adolescents in Korea based on the Youth Risk Behavior Survey (2015-2020)

Youngrong Lee, Ye Jin Jeon, Jee-Seon Shim, Sun Jae Jung Epidemiol Health. 2022;44:e2022033.

COVID-19: Original Article Unemployment and COVID-19-related mortality: a historical cohort study of 50,000 COVID-19 patients in Fars, Iran

Alireza Mirahmadizadeh, Mohammad Taghi Badeleh Shamooshaki, Amineh Dadvar, Mohammad Javad Moradian, et al. Epidemiol Health. 2022;44:e2022032.

Abstract: OBJECTIVES:
This study explored the association between dietary and suicidal behaviors of Korean adolescents and investigated differences in this association in children of immigrant parents.
METHODS:
The sample (n=368,138) was collected from the Korea Youth Risk Behavior Survey from 2015 to 2020. Participants who agreed to provide family information (n=313,689) were classified according to their parents’ nationality. The study variables were 11 self-reported dietary behaviors, and their composite dietary behaviors (i.e., nutrient deprivation and unhealthy food consumption) that resulted from principal component analysis. The association between study variables and suicide-related outcomes (i.e., suicidal ideation, suicide planning, and suicide attempts) was analyzed by multiple logistic regression with adjustment for covariates. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated.
RESULTS:
Participants who skipped key meals and foods were more likely to have attemped suicide (aOR [95% CI]: skipping breakfast ≥5 days/wk, 1.28 [1.21 to 1.35]; consuming fruits <1 times/wk: 1.42 [1.32 to 1.52]; consuming vegetables <1 times/wk: 1.72 [1.53 to 1.93]; consuming milk <3 times/wk: 1.07 [0.99 to 1.16]). The associations were prominent in third culture kids (TCKs) (aOR [95% CI]: 2.23 [1.61 to 3.09]; 2.32 [1.61 to 3.35]; 2.63 [1.50 to 4.60]; 1.69 [1.09 to 2.63], respectively). Participants who consumed unhealthy foods (fast food, caffeinated and sugary drinks) more frequently were more likely to have attempted suicide (aOR, 1.55; 95% CI, 1.38 to 1.73). This association was also more prominent in TCKs (aOR, 2.08; 95% CI, 1.08 to 4.01).
CONCLUSIONS:
Our findings indicate a positive association between unfavorable dietary behaviors and outcomes related to suicide, and this association appears to be notable in adolescents with immigrant parents.

Abstract: OBJECTIVES:
Previous studies have estimated the risk of death associated with unemployment in the coronavirus disease 2019 (COVID-19) pandemic, but no studies have examined unemployment before COVID-19 infection as a risk factor for COVID-19-related mortality. Thus, this study aimed to investigate COVID-19 mortality among this population.
METHODS:
Data on 50,038 people aged 25-59 years were collected from 38 agencies in Fars Province, Iran, from February 2020 to July 2021. Follow-up lasted from participants’ diagnosis with COVID-19 based on the results of a reverse transcription-polymerase chain reaction test to participants’ death or the end of the study period. The association between unemployment and COVID-19-related mortality was estimated using the Poisson regression method, and a sensitivity analysis was conducted to calculate the E-value.
RESULTS:
Unemployment was associated with a 2.41-fold (95% confidence interval [CI], 2.01 to 2.90) higher age-adjusted and sex-adjusted risk of COVID-19-related mortality. The adjusted Poisson regression analysis showed 8.82 (95% CI, 6.42 to 12.11), 2.84 (95% CI, 1.90 to 4.24), and 1.58 (95% CI, 1.24 to 2.01) times higher risks of COVID-19-related mortality among unemployed people aged 25-39 years, 40-49 years, and 50-59 years, respectively, than among their employed counterparts. Unemployment increased the risk of COVID-19 mortality by 3.31 (95% CI, 2.31 to 4.74) and 2.30 (95% CI, 1.86 to 2.84) times in female and male, respectively. The E-value was 3.43, reflecting the minimum strength of confounding required to shift the association between unemployment and COVID-19-related mortality toward the null.
CONCLUSIONS:
Unemployment prior to COVID-19 infection increased the risk of COVID-19-related mortality. COVID-19-related mortality disproportionately impacted unemployed women and younger unemployed people.

Perspective Measles susceptibility of marriage migrant women in Korea

Sooyeon Kim, Sun A Kim, Hanbich Hong, Seong Ryeong Choi, et al. Epidemiol Health. 2022;44:e2022031.

Original Article Recent trends in opioid prescriptions in Korea from 2002 to 2015 based on the Korean NHIS-NSC cohort

Joungyoun Kim, Sang-Jun Shin, Jihyun Yoon, Hyeong-Seop Kim, et al. Epidemiol Health. 2022;44:e2022029.

Abstract: International migrants could be considered a risk group susceptible to vaccine-preventable diseases. We conducted a measles seroprevalence study among 419 marriage migrant women living in Sinan-gun and Wando-gun, South Jeolla Province, located in the southwestern part of Korea. The overall seroimmunity was 92.8%. The seroimmunity varied considerably according to the country of origin and increased with age. Our current analysis could be valuable in the context of discussions concerning vaccination policies for immigrants in Korea.

Abstract: OBJECTIVES:
Opioids are prescribed to treat moderate to severe pain. We investigated recent trends in opioid (morphine, oxycodone, fentanyl, and hydromorphone) prescriptions using data from the Korean National Health Insurance Service-National Sample Cohort between 2002 and 2015.
METHODS:
The morphine milligram equivalent (MME) was calculated to standardize the relative potency of opioids. The number (cases) or amount (MME) of annual opioid prescriptions per 10,000 registrants was computed to analyze trends in opioid prescriptions after age standardization. Joinpoint regression analysis was conducted to calculate the annual percentage change and average annual percentage change (AAPC).
RESULTS:
The number (cases) of prescriptions per 10,000 registrants increased from 0.07 in 2002 to 41.23 in 2015 (AAPC, 76.0%; 95% confidence interval [CI], 61.6 to 91.7). The MME per 10,000 registrants increased from 15.06 in 2002 to 40,727.80 in 2015 (AAPC, 103.0%; 95% CI, 78.2 to 131.3). The highest AAPC of prescriptions and MME per 10,000 registrants were observed in the elderly (60-69 years) and in patients treated at general hospitals. Fentanyl prescriptions increased most rapidly among the 4 opioids.
CONCLUSIONS:
Consumption of opioids greatly increased in Korea over the 14-year study period.

COVID-19: Original Article Seroprevalence of SARS-CoV-2 antibodies in the community based on participants in the 2020 Korea National Health and Nutrition Examination Survey

Ah-Ra Kim, Dohsik Minn, Su Hwan Kim, Hyeon Nam Do, et al. Epidemiol Health. 2022;44:e2022028.

Original Article Association between levels of physical activity and low handgrip strength: Korea National Health and Nutrition Examination Survey 2014-2019

Hyungsoon Ahn, Hwa Young Choi, Moran Ki Epidemiol Health. 2022;44:e2022027.

Abstract: OBJECTIVES:
The Korea National Health and Nutrition Examination Survey (KNHANES) is a nationwide cross-sectional surveillance system that assesses the health and nutritional status of the Korean population. To evaluate the occurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the community, we investigated the prevalence of anti-SARS-CoV-2 antibodies in the sera of KNHANES participants.
METHODS:
Subjects were recruited between April 24 and December 12, 2020. In total, 5,284 subjects aged 10-90 years from 17 regions participated. SARS-CoV-2 antibodies were screened using the Elecsys Anti-SARS-CoV-2 assay. Positive samples were verified using 4 different SARS-CoV-2 antibody assays and the plaque reduction neutralizing test. The final seropositivity criteria were a positive screening test and at least 1 positive result from the 5 additional tests.
RESULTS:
Almost half (49.2%; 2,600/5,284) of participants were from metropolitan areas, 48.9% were middle-aged (40-69 years), and 20.5% were in their 20s or younger. The seropositivity rate was 0.09% (5/5,284). Three of the 5 antibody-positive subjects had a history of infection, of whom 2 were infected abroad and 1 was infected in a local cluster outbreak.
CONCLUSIONS:
The low SARS-CoV-2 antibody seroprevalence in Korea indicates that there have been few coronavirus disease 2019 (COVID-19) cases due to successful COVID-19 management measures (e.g., diagnostic tests for overseas arrivals, national social distancing, and strict quarantine measures). Moreover, asymptomatic infections were uncommon due to active polymerase chain reaction testing. However, hidden infections may exist in the community, requiring the continuation of quarantine and vaccination measures.

Abstract: OBJECTIVES:
This study aimed to investigate the association between levels of physical activity (PA) and low handgrip strength in Korean adults.
METHODS:
Our cross-sectional study design included 24,109 Korean adults older than 19 years of age who participated in the Korea National Health and Nutrition Examination Survey 2014–2019. Low handgrip strength is described as hand strength less than the cut-off value of the 20th percentile of handgrip strength from a healthy population in each gender and age group. PA was categorized into three levels (inactive, active, and highly active) according to the World Health Organization’s global recommendations on PA for health. Multivariable logistic regression analysis was used to examine the association between levels of PA and low handgrip strength.
RESULTS:
Odds ratios (ORs) for low handgrip strength were significantly higher in middle-aged women who were active (adjusted odds ratio [aOR], 1.40; 95% confidence interval [CI], 1.15 to 1.69) and inactive (aOR, 1.47; 95% CI, 1.23 to 1.76) than in those highly active in walking exercise. Most of older people had significantly higher ORs for low handgrip strength in active compared to highly active in the context of aerobic, muscle strengthening, and walking exercise.
CONCLUSIONS:
Walking exercise was associated with a lower risk of sarcopenia in middle-aged women and older individuals. However, further studies are necessary to confirm the causal relationship between levels of PA and low handgrip strength.

COVID-19: Original Article The medium-term consequences of a COVID-19 lockdown on lifestyle among Spanish older people with hypertension, pulmonary disease, cardiovascular disease, musculoskeletal disease, depression, and cancer

Irene Rodríguez-Gómez, Coral Sánchez-Martín, Francisco J. García-García, Esther García-Esquinas, et al. Epidemiol Health. 2022;44:e2022026.

Original Article Associations of fasting glucose and glycated hemoglobin with vitamin D levels according to diabetes mellitus status in Korean adults

Yerin Hwang, Jiyoung Jang, Myung-Hee Shin Epidemiol Health. 2022;44:e2022025.

Abstract: OBJECTIVES:
This study investigated the associations of chronic diseases with changes in lifestyle and health behaviours in older people following the coronavirus disease 2019 (COVID-19) lockdown in Spain and compared the differences in changes over time.
METHODS:
1,092 participants (80.3±5.6 years; 66.5% female) from 2 Spanish cohorts were included. Telephone-based questionnaires were conducted to evaluate lifestyle and health risk behaviours at the end of lockdown and 7 months post-lockdown. Participants were classified as having physician-diagnosed chronic diseases based on self-reported data. Cox proportional models adjusted for major confounders were used.
RESULTS:
Compared to those without the corresponding chronic diseases, older people with hypertension were less likely to report increased alcohol consumption (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.55 to 0.99). Pulmonary diseases were associated with lower risks of increased sedentary time (HR, 0.58; 95% CI, 0.39 to 0.86) and worsened sleep quality (HR, 0.56; 95% CI, 0.36 to 0.87), while cardiovascular diseases were associated with a lower risk of decreased sedentary time (HR, 0.58; 95% CI, 0.38 to 0.88). Depression was linked to a higher likelihood of improved diet quality (HR, 1.53; 95% CI, 1.00 to 2.36). Cancer pacients were less likely to have worsened sleep quality (HR, 0.44; 95% CI, 0.22 to 0.89) but more likely to have reduced their frequency of social contact (HR, 2.05; 95% CI, 1.05 to 3.99).
CONCLUSIONS:
Older people with chronic diseases showed beneficial changes in lifestyle and health risk behaviours after the COVID-19 lockdown. In particular, older people with hypertension, pulmonary disease, and cancer tended to make beneficial lifestyle and health behaviour changes. However, older people with cardiovascular disease and depression engaged in more health risk behaviours.

Abstract: OBJECTIVES:
According to previous studies, vitamin D deficiency might increase the risk of type 2 diabetes mellitus (DM). However, few studies have examined whether vitamin D continues to affect glucose control after DM diagnosis. Therefore, we examined the association between vitamin D and glucose levels in individuals with and without DM.
METHODS:
We analyzed data for 32,943 adults aged 19 years and older from the 2008 to 2014 Korea National Health and Nutrition Examination Survey. Patients were classified into 3 groups according to the 25-hydroxyvitamin D concentration. DM was defined as a fasting glucose level ≥126 mg/dL, current use of DM medications or insulin injections, or a self-reported diagnosis of DM by a doctor.
RESULTS:
In male DM patients, the hemoglobin A1c (HbA1c) level increased significantly as vitamin D levels became severely deficient. In male and postmenopausal female with abnormal HbA1c, those with severe vitamin D deficiency had significantly higher HbA1c levels (p for trend=0.004 and 0.022 for male and postmenopausal female, respectively). Significant differences were found between participants with normal and abnormal HbA1c levels in both male and female. However, regardless of sex or menopausal status, there was no significant association between vitamin D and fasting glucose in any of the fasting glucose subgroups.
CONCLUSIONS:
Male and female with abnormal HbA1c levels showed markedly elevated blood glucose when they also had vitamin D deficiency. A more distinct difference was observed in the HbA1c subgroups than in the fasting glucose subgroups.

Original Article Differences in accuracy of height, weight, and body mass index between self-reported and measured using the 2018 Korea Community Health Survey data

Yoonsil Ko, Sunhye Choi, Jisoo Won, Yeon-Kyeng Lee, et al. Epidemiol Health. 2022;44:e2022024.

Original Article Secular trends and related factors in leisure-time sedentary behavior among Koreans: an analysis of data from the 2011-2017 Korea Community Health Survey

Hyun-Ju Seo, Min-Jung Choi, Soon-Ki Ahn Epidemiol Health. 2022;44:e2022023.

Abstract: OBJECTIVES:
This study aimed to determine an effective survey method for the accurate calculation of obesity prevalence by comparing the self-reported and measured height, weight, and body mass index (BMI) using the 2018 Korea Community Healthy Survey (CHS) data.
METHODS:
Raw data from the 2018 CHS were used to analyze the differences, correlation, and agreement between self-reported and measured height, weight, and BMI.
RESULTS:
The self-reported height was over-reported than the measured height (0.59 cm greater for men and 0.71 cm greater for women), while the self-reported weight was under-reported than the measured weight (0.55 kg less for men and 0.67 kg less for women). Subsequently, the self-reported BMI was under-estimated (0.35 kg/m² lower for men and 0.49 kg/m² lower for women) compared with the measured BMI. The kappa statistic and agreement between measured and self-reported values per BMI category (underweight, normal, overweight, and obesity) were 0.82 and 79.6%, respectively.
CONCLUSIONS:
The prevalence of obesity should be calculated using the measured values provided in the CHS in order to promote local health projects based on accurate evidence.

Abstract: OBJECTIVES:
Sedentary behavior has gradually increased and has become a public health problem. Therefore, this study investigated trends in weekday leisure-time sedentary behaviors, as well as characteristic socio-demographic and lifestyle correlates in Korean adults.
METHODS:
We analyzed data from 914,946 adults aged ≥19 years who participated in the Korea Community Health Survey (2011, 2013, 2015, and 2017). Leisure-time sedentary behavior was categorized as a binary variable (<4 and ≥4 hr/day). Multivariable regression analysis was used to model the prevalence of sedentary behavior and estimate odds ratios.
RESULTS:
The prevalence of leisure-time sedentary behavior decreased from 15.2% to 14.4% in men and from 16.6% to 16.0% in women between 2011 and 2017, respectively. However, a significant increase was observed in subjects with an education lower than high school in both genders (β coefficient=0.12 for men and 0.08 for women, p for trend <0.001). Women in the lowest household income level (β coefficient=0.08, p for trend=0.001) and with poor subjective health status (β coefficient=0.05, p for trend=0.013) showed an increasing trend. Other factors associated with sedentary behavior were age, education level, body mass index, household income, walking activity, perceived stress level, and subjective health status in both genders.
CONCLUSIONS:
Identifying the secular trends and correlates of sedentary behavior by gender and associated factors will provide empirical evidence for developing public health campaigns and promotion programs to reduce sedentary behavior in Koreans.

Original Article The relationship between poor sleep quality measured by the Pittsburgh Sleep Quality Index and smoking status according to sex and age: an analysis of the 2018 Korean Community Health Survey

Jun Hyun Hwang, Soon-Woo Park Epidemiol Health. 2022;44:e2022022.

Data Profile The Korea National Health and Nutrition Examination Survey data linked Cause of Death data

Sungha Yun, Kyungwon Oh Epidemiol Health. 2022;44:e2022021.

Abstract: OBJECTIVES:
Multiple studies have found that cigarette smokers are more likely to experience sleep disturbances than non-smokers. This study aimed to examine various associations between smoking and sleep quality according to sex and age, which have yet to be sufficiently examined in prior studies.
METHODS:
Data analysis was conducted using a nationally representative sample of 224,986 Korean adults who participated in the 2018 Korea Community Health Survey. Sleep quality, as the dependent variable, was measured using the Pittsburgh Sleep Quality Index (PSQI), with PSQI scores indicating either good (≤4 points) or poor (>5 points) sleep quality. Multiple logistic regression analysis was performed considering socio-demographic factors, health behaviors, comorbidities, and psychological factors as covariates.
RESULTS:
The overall weighted prevalence of poor sleep quality was 39.4% (95% confidence interval, 39.1 to 39.7). In the multivariate model that excluded psychological factors, poor sleep quality positively correlated to smoking for both sexes and all age groups except for male aged ≥65 years. However, in the full model that included psychological factors, statistically significant odds ratios (approximately 1.5) for poor sleep quality according to smoking status were only observed for female under 65 years of age.
CONCLUSIONS:
The relationship between poor sleep quality and smoking status differed according to sex and age. In order to improve the quality of sleep, it is necessary to intervene smoking cessation along with solving psychological problems, especially female in middle age and younger.

Abstract: The Korea National Health and Nutrition Examination Survey (KNHANES) is a national health survey that is conducted annually to assess the health and and health-related behaviors of Korean population. To utilize KNHANES data to studies of mortality risk factors, the Korea Disease Control and Prevention Agency (KDCA) constructed a database linking KNHANES data to cause-of-death statistics in Statistics Korea, made available to researchers since 2020. The KNHANES data were linked to the Cause of Death Statistics based on resident registration numbers for subjects aged 19 years or older who agreed to link the data. The linkage rate between 2007-2015 National Health and Nutrition Examination Survey and 2007-2019 Cause of Death Statistics was 97.1%. In the linked dataset, the total death rate was 6.6%, of which neoplasms accounted for the highest death rate (32.1%), followed by circulatory system disease (22.7%) and respiratory system disease (11.5%). The linked dataset was made available through the Research Data Center of the KDCA after a review of the research proposal, and will be made available after periodical updates.

COVID-19: Original Article The general public’s perspectives on telemedicine during the COVID-19 pandemic in Korea: analysis of a nationwide survey

EunKyo Kang, Hyejin Lee, Ki Jeong Hong, Jieun Yun, et al. Epidemiol Health. 2022;44:e2022020.

Original Article Dairy product consumption and type 2 diabetes among Korean adults: a prospective cohort study based on the Health Examinees (HEXA) study

Jiaqi Zhang, Kyungjoon Lim, Sangah Shin Epidemiol Health. 2022;44:e2022019.

Abstract: OBJECTIVES:
We investigated the awareness, experience, approval, intention to use, and the desired type of telemedicine among Korean general public.
METHODS:
From November to December 2020, we conducted an online self-reported survey on awareness, experience, approval, and intent to use telemedicine services among Korean residents aged 20 years or older. A total of 2,097 participants completed the survey.
RESULTS:
Of the 2,097 participants, 1,558 (74.3%) were aware of, 1,198 (57.1%) approved of, and 1,474 (70.3%) had the intention to use telemedicine. Participants from regions other than the Seoul metropolitan area and Daegu–Gyeongbuk Province (adjusted odds ratio [aOR], 1.29; 95% confidence interval [CI], 1.02 to 1.63), households with a monthly household income of US$6,000 or more (aOR, 1.44; 95% CI, 1.01 to 2.08), participants who had a college/university or associate’s degree (aOR, 1.35. 95% CI, 1.04 to 1.75) or a master’s degree or above (aOR, 1.73; 95% CI, 1.20 to 2.50), and housewives (aOR, 1.30; 95% CI, 1.03 to 1.64) had higher odds of approval. Elderly participants, those with a chronic disease (aOR, 1.26; 95% CI, 1.04 to 1.54), those who had experienced delays of healthcare services (aOR, 1.94; 95% CI, 1.27 to 2.96), and those who had experience with telemedicine (aOR, 4.28; 95% CI, 1.69 to 10.82) were more likely to intend to use telemedicine services. Regarding types of telemedicine, teleconsultation between doctors showed the highest approval rate (73.1%).
CONCLUSIONS:
In the context of the coronavirus disease 2019 pandemic, more than 70% of participants had already used or intended to use telemedicine at some point. Groups with a substantial need for telemedicine were more in favor of telemedicine.

Abstract: OBJECTIVES:
It has been suggested that the consumption of dairy products helps lower the prevalence of type 2 diabetes (T2D). We investigated the association between the consumption of dairy products and T2D events in middle-aged Korean adults.
METHODS:
We followed up 53,288 participants (16,895 male and 36,393 female) in the Health Examinees (HEXA) study. The consumption of dairy products was assessed using the self-administered food frequency questionnaire, and T2D was defined according to the 2015 treatment guidelines of the Korean Diabetes Association. Hazard ratios (HRs) and 95% confidence intervals (CIs) between the consumption of dairy products and the risk of T2D were calculated using Cox proportional hazards models after adjusting for potential confounders. Spline regression was used to better represent the association between the consumption of dairy products and the risk of T2D.
RESULTS:
Among male, those with higher consumption of dairy products had a significantly lower risk of T2D than those who consumed essentially no dairy products (HR, 0.73; 95% CI, 0.58 to 0.91). In particular, consumption of yogurt (HR, 0.75; 95% CI, 0.60 to 0.93; p_trend=0.035) and cheese (HR, 0.66; 95% CI, 0.49 to 0.89; p_trend=0.005) was negatively associated with the incidence of T2D in male. In female, daily consumption of 1 serving of yogurt decreased the risk of T2D by 11%.
CONCLUSIONS:
The association between the consumption of dairy products and the risk of T2D differed by sex and dairy product type. Further prospective studies are needed to confirm these associations.

COVID-19: Original Article Depression, anxiety, and stress in Korean general population during the COVID-19 pandemic

Hooyeon Lee, Dongwoo Choi, Jung Jae Lee Epidemiol Health. 2022;44:e2022018.

Original Article Elder abuse/mistreatment and associated covariates in India: results from the Longitudinal Aging Study in India wave 1, 2017-2018

Thennavan Sathya, Yesuvadian Selvamani, Rangasamy Nagarajan Epidemiol Health. 2022;44:e2022017.

Abstract: OBJECTIVES:
The aim of this study was to investigate the prevalence and risk factors of poor mental health in the general Korean population during the coronavirus disease 2019 (COVID-19) pandemic.
METHODS:
This cross-sectional, population-based, online survey-based study was conducted from November 5 to 20, 2020 and included adults aged 20-49 years in Chungnam Province, Korea. A total of 549 adults were included.
RESULTS:
In total, 18.8% of the participants had symptoms of depression, 10.6% had symptoms of anxiety, and 5.1% had a high level of perceived stress during the COVID-19 pandemic. Higher levels of stress (odds ratio [OR], 3.13; 95% confidence interval [CI], 1.13 to 8.67), anxiety (OR, 2.33; 95% CI, 1.09 to 4.49), and depression (OR, 3.00; 95% CI, 1.64 to 5.50) were found among never married, widowed, divorced, and separated people than among married/cohabiting/partnered participants. Participants who felt increased stress at home during the COVID-19 outbreak reported more depression (OR, 2.45; 95% CI, 1.49 to 4.05) and anxiety (OR, 2.42; 95% CI, 1.31 to 4.50). Women had higher risks of anxiety (OR, 1.97; 95% CI, 1.09 to 3.58) and stress (OR, 6.40; 95% CI, 2.30 to 17.85) than men. Participants with the highest household income were less likely to report symptoms of stress than those with the lowest household income (OR, 0.24; 95% CI, 0.06 to 0.96).
CONCLUSIONS:
The participants in this study exhibited poor mental health index scores, suggesting that some people are at risk for mental health problems during the COVID-19 pandemic. Being married was independently and significantly associated with a lower likelihood of depression, anxiety, and stress.

Abstract: OBJECTIVES:
Elder abuse has significant adverse consequences for the overall health and well-being of the elderly, including premature mortality. Using cross-sectional data, we assessed the prevalence of elder abuse in India, its variation across states, and associated factors.
METHODS:
Nationally representative data from the first wave of the Longitudinal Aging Study in India were analyzed. Bivariate and multivariate analyses were used to study the prevalence, state variations, and associated factors of elder abuse.
RESULTS:
Overall, 5.2% of elderly adults (≥60 years) had experienced abuse in the year prior to the survey and 3% had experienced abuse within their own household. Verbal abuse or disrespect was the most common form of abuse. Considerable variation was observed in the prevalence of elder abuse across states and union territories, with the highest prevalence observed in Bihar (11.6%) and Karnataka (10.1%). In regression analysis, education level emerged as a protective factor against elder abuse, particularly among women. Older adults who lived alone, had functional limitations, had multiple morbidities, and had been hospitalized in the past year were more likely to experience abuse. Older adults who experienced abuse were 2 times more likely to experience depressive symptoms.
CONCLUSIONS:
Cross-state variation in the prevalence of elder abuse and subgroup differences suggest that state-specific interventions and essential monitoring of older adults with functional limitations, chronic diseases, and recent hospitalization can further reduce the prevalence and consequences of elder abuse in India.

Original Article Local-level spatiotemporal dynamics of COVID-19 transmission in the Greater Seoul Area, Korea: a view from a Bayesian perspective

Youngbin Lym, Hyobin Lym, Ki-Jung Kim Epidemiol Health. 2022;44:e2022016.

COVID-19: Perspective Neglecting the neglected during the COVID-19 pandemic: the case of leptospirosis in Sri Lanka

Janith Warnasekara, Suneth Agampodi Epidemiol Health. 2022;44:e2022015.

Abstract: OBJECTIVES:
The purpose of this study was to enhance the understanding of the local-level spatiotemporal dynamics of COVID-19 transmission in the Greater Seoul Area (GSA), Korea, after its initial outbreak in January 2020.
METHODS:
Using the weekly aggregates of coronavirus disease 2019 (COVID-19) cases of 77 municipalities in the GSA, we examined the relative risks of COVID-19 infection across local districts over 50 consecutive weeks in 2020. To this end, we employed a spatiotemporal generalized linear mixed model under the hierarchical Bayesian framework. This allowed us to empirically examine the random effects of spatial alignments, temporal autocorrelation, and spatiotemporal interaction, along with fixed effects. Specifically, we utilized the conditional autoregressive and the weakly informative penalized complexity priors for hyperparameters of the random effects.
RESULTS:
Spatiotemporal interaction dominated the overall variability of random influences, followed by spatial correlation, whereas the temporal correlation appeared to be small. Considering these findings, we present dynamic changes in the spread of COVID-19 across local municipalities in the GSA as well as regions at elevated risk for further policy intervention.
CONCLUSIONS:
The outcomes of this study can contribute to advancing our understanding of the local-level COVID-19 spread dynamics within densely populated regions in Korea throughout 2020 from a different perspective, and will contribute to the development of regional safety planning against infectious diseases.

Abstract: The coronavirus disease 2019 (COVID-19) pandemic has disrupted global health systems and affected the transmission dynamics as well as the surveillance of other infectious diseases. This study described the probable effect of the COVID-19 pandemic on the surveillance and control of leptospirosis in Sri Lanka. With 8,579 reported cases and more than 800 estimated deaths, the Sri Lankan public health surveillance system documented the largest outbreak of leptospirosis in Sri Lankan history in 2020. This was the worst infectious disease outbreak Sri Lanka experienced in 2020, but it was neglected, primarily due to the COVID-19 pandemic.

Methods Development and validation of the Pediatric-Youth Hyperphagia Assessment for Prader-Willi syndrome

Sung Yoon Cho, Danbee Kang, Minji Im, Aram Yang, et al. Epidemiol Health. 2022;44:e2022014.

COVID-19: Original Article Socioeconomic inequality in compliance with precautions and health behavior changes during the COVID-19 outbreak: an analysis of the Korean Community Health Survey 2020

Ga Bin Lee, Sun Jae Jung, Yang Yiyi, Jea Won Yang, et al. Epidemiol Health. 2022;44:e2022013.

Abstract: OBJECTIVES:
Hyperphagia is a highly stressful, life-threatening feature of Prader-Willi syndrome (PWS). It is important to assess this complex behavior accurately over time. This study aimed to develop and validate the Pediatric-Youth Hyperphagia Assessment for Prader-Willi syndrome (PYHAP) as a tool targeting children and adolescents.
METHODS:
After an extensive literature review and qualitative interviews, the final version of the PYHAP with 14 questions in 3 domains (verbal [5], behavior [4], and social [5]) was developed and tested at Samsung Medical Center in Seoul, Korea from July 2018 to September 2019. Exploratory factor analysis and confirmatory factor analysis (CFA) were performed to confirm construct validity. The correlations between the PYHAP and the Korean Children’s Eating Behavior Questionnaire (K-CEBQ) were calculated to evaluate convergent and discriminant validity. Criterion validity and the validity of the response categories were also tested.
RESULTS:
Cronbach’s alpha coefficient of the PYHAP was 0.91. The fit indices for CFA were good (comparative fit index, 0.87; standardized root mean squared residual, 0.08). The domains of the PYHAP were closely correlated with the relevant domains of the K-CEBQ. The accuracy of the PYHAP score for predicting uncontrolled hyperphagia was good (area under the curve, 0.75; 95% confidence interval, 0.65 to 0.85).
CONCLUSIONS:
The PYHAP was confirmed to be a reliable and valid tool to evaluate hyperphagia in children and adolescents with PWS via caregivers’ assessments. It is recommended to use the PYHAP to communicate with parents or caregivers about patients’ hyperphagia or to monitor and manage extreme behaviors in children with PWS.

Abstract: OBJECTIVES:
This study examined socioeconomic inequalities in compliance with precautions and health behavior changes during the coronavirus disease 2019 (COVID-19) outbreak using a representative Korean sample.
METHODS:
This exploratory study utilized around 210,000 participants aged ≥25 years in the Korean Community Health Survey 2020. Socioeconomic status was measured with educational attainment and household income. Outcomes included non-compliance with 8 precaution measures and deterioration in 6 health behaviors. The relative inequality index (RII) was calculated to quantify the degree of inequality by education and income level. RII values >1.0 indicate that deprived people have a higher frequency of health problems, and RII values <1.0 conversely indicate a higher frequency of health problems in more advantaged groups.
RESULTS:
People with lower education or income levels tended to have higher rates of non-compliance with COVID-19 safety precautions (RII range, 1.20 to 3.05). Lower education and income levels were associated with an increased smoking amount (RII=2.10 and 1.67, respectively) and sleep duration changes (RII=1.21 and 1.36, respectively). On the contrary, higher education and income levels were associated with decreased physical activity (RII=0.59 and 0.77, respectively) and increased delivery food consumption (RII=0.27 and 0.37, respectively). However, increased alcohol drinking was associated with lower education and income levels in younger men (RII=1.73 and 1.31, respectively), but with higher levels in younger women (RII=0.73 and 0.68, respectively).
CONCLUSIONS:
Our findings suggest the need to develop customized strategies, considering the characteristics of the target population, to decrease the burden and impact of the COVID-19 outbreak.

Original Article Independent predictors of depressive symptoms and social isolation on 2-year all-cause mortality among the Korean elderly in a population-based cohort study: gender differences

Hyunsuk Jeong, Hyeon Woo Yim, Beom-Woo Nam Epidemiol Health. 2022;44:e2022012.

COVID-19: Brief Communication Trends in gastrointestinal infections before and during non-pharmaceutical interventions in Korea in comparison with the United States

Soyeoun Kim, Jinhyun Kim, Bo Youl Choi, Boyoung Park Epidemiol Health. 2022;44:e2022011.

Abstract: OBJECTIVES:
This study examined whether depressive symptoms and social isolation were independent predictors of 2-year all-cause mortality among the elderly using data from a population-based cohort study.
METHODS:
In total, 1,033 participants (320 men and 713 women) older than 60 years of age participated in this study. Depressive symptoms, social isolation status, and socio-demographic and health-related covariates were assessed at baseline. The primary outcome measure was 2-year all-cause mortality. Data were collected through in-person interviews by trained interviewers. The GENMOD procedure was used to calculate relative risks (RRs).
RESULTS:
Of the 1,033 participants, 102 (40 men and 62 women) died within the follow-up period of 2 years. During the 2-year follow-up period, 17.8% of depressed men and 12.3% of depressed women died, and 29.8% of socially isolated men and 14.9% of socially isolated women died. Social isolation was an independent predictor of mortality in elderly men (adjusted relative risk [aRR], 4.6, 95% confidence interval [CI], 2.0 to 10.2), while depressive symptoms were an independent predictor of mortality in elderly women (aRR, 2.0; 95% CI, 1.2 to 3.6) when controlling for potential confounding factors. However, the depressive symptoms detected using the geriatric depression scale were not associated with mortality in men, and social isolation was not associated with mortality in women.
CONCLUSIONS:
The effects of depressive symptoms and social isolation on 2-year all-cause mortality within an elderly population differed according to gender. Gender-specific community-based interventions must be developed to potentially reduce 2-year all-cause mortality among the elderly.

Abstract: OBJECTIVES:
This study examined how trends in the weekly frequencies of gastrointestinal infectious diseases changed before and during the coronavirus disease 2019 (COVID-19) pandemic in Korea, and compared them with the trends in the United States.
METHODS:
We compared the weekly frequencies of gastrointestinal infectious diseases (16 bacterial and 6 viral diseases) in Korea during weeks 5-52 before and after COVID-19. In addition, the weekly frequencies of 5 gastrointestinal infectious diseases in the United States (data from the Centers for Disease Control and Prevention) that overlapped with those in Korea were compared.
RESULTS:
The mean weekly number of total cases of gastrointestinal infectious diseases in Korea showed a significant decrease (from 522 before COVID-19 to 245 after COVID-19, p<0.01). Only bacterial gastrointestinal infectious diseases caused by Campylobacter increased significantly; other bacterial gastrointestinal infectious diseases showed either a decrease or no change. The incidence of all other viral diseases decreased. In the United States, the weekly numbers of Salmonella, Campylobacter, typhoid, shigellosis, and hepatitis A virus cases sharply decreased after the COVID-19 outbreak. The weekly case numbers of all viral diseases markedly decreased in both countries; however, bacterial gastrointestinal infectious diseases showed a different pattern.
CONCLUSIONS:
The incidence of gastrointestinal infectious diseases decreased after the COVID-19 outbreak. In contrast, Campylobacter infections showed an increasing trend in Korea, but a decreasing trend in the United States. Further studies are needed to elucidate the different trends in bacterial and viral infectious diseases before and after non-pharmaceutical interventions and between different countries.

Original Article Increasing trends in mortality and costs of infectious diseases in Korea: trends in mortality and costs of infectious diseases

Dahye Baik, Byung-Woo Kim, Moran Ki Epidemiol Health. 2022;44:e2022010.

Original Article The predictive value of resting heart rate in identifying undiagnosed diabetes in Korean adults: Korea National Health and Nutrition Examination Survey

Dong-Hyuk Park, Wonhee Cho, Yong-Ho Lee, Sun Ha Jee, et al. Epidemiol Health. 2022;44:e2022009.

Abstract: OBJECTIVES:
In an era when the average life expectancy and overall mortality rate have improved, Korea remains at risk for infectious disease outbreaks that place substantial burdens on the healthcare system. This study investigated trends in mortality and the economic burden of infectious diseases.
METHODS:
Healthcare data from the Health Insurance Review and Assessment Service (2009-2019) and the Korean Statistics Information Service (1997-2019) were used. We selected 10 infectious disease groups (intestinal infections, tuberculosis, vaccine- preventable diseases, sepsis, viral hepatitis, HIV-related diseases, central nervous system infections, rheumatic heart diseases, respiratory tract infections, and arthropod-borne viral diseases).
RESULTS:
The age-standardized mortality rate for infectious diseases increased from 27.2 per 100,000 population in 1997 to 37.1 per 100,000 population in 2019 and has had an upward trend since 2004. During this same period, significant increases were seen in respiratory tract infections and among elderly persons, especially those aged ≥85 years. The costs for infectious diseases increased from 4.126 billion US dollar (USD) in 2009 to 6.612 billion USD in 2019, with respiratory tract infections accounting for 3.699 billion USD (69%). The annual cost per patient for visits for medical care due to infectious diseases increased from 131 USD in 2009 to 204 USD in 2019.
CONCLUSIONS:
Mortality among elderly persons and those with respiratory tract infections increased during the study period. The economic burden of infectious diseases has consistently increased, especially for respiratory tract infections. It is therefore essential to establish effective management policies that considers specific infectious diseases and patient groups.

Abstract: OBJECTIVES:
The purpose of this study was (1) to examine whether the addition of resting heart rate (RHR) to the existing undiagnosed diabetes mellitus (UnDM) prediction model would improve predictability, and (2) to develop and validate UnDM prediction models by using only easily assessable variables such as gender, RHR, age, and waist circumference (WC).
METHODS:
Korea National Health and Nutrition Examination Survey (KNHANES) 2010, 2012, 2014, 2016 data were used to develop the model (model building set, n=19,675), while the data from 2011, 2013, 2015, 2017 were used to validate the model (validation set, n=19,917). UnDM was defined as a fasting glucose level ≥126 mg/dL or glycated hemoglobin ≥6.5%; however, doctors have not diagnosed it. Statistical package for the social sciences logistic regression analysis was used to determine the predictors of UnDM.
RESULTS:
RHR, age, and WC were associated with UnDM. When RHR was added to the existing model, sensitivity was reduced (86 vs. 73%), specificity was increased (49 vs. 65%), and a higher Youden index (35 vs. 38) was expressed. When only gender, RHR, age, and WC were used in the model, a sensitivity, specificity, and Youden index of 70%, 67%, and 37, respectively, were observed.
CONCLUSIONS:
Adding RHR to the existing UnDM prediction model improved specificity and the Youden index. Furthermore, when the prediction model only used gender, RHR, age, and WC, the outcomes were not inferior to those of the existing prediction model.

Systematic Review Quantifying the duration of the preclinical detectable phase in cancer screening: a systematic review

Sandra M. E. Geurts, Anne M. W. M. Aarts, André L. M. Verbeek, Tony H. H. Chen, et al. Epidemiol Health. 2022;44:e2022008.

Original Article Impact of water fluoridation on dental caries decline across racial and income subgroups of Brazilian adolescents

Rafael Aiello Bomfim, Paulo Frazão Epidemiol Health. 2022;44:e2022007.

Abstract: OBJECTIVES:
The aim of this study was to provide an overview of published mathematical estimation approaches to quantify the duration of the preclinical detectable phase (PCDP) using data from cancer screening programs.
METHODS:
A systematic search of PubMed and Embase was conducted for original studies presenting mathematical approaches using screening data. The studies were categorized by mathematical approach, data source, and assumptions made. Furthermore, estimates of the duration of the PCDP of breast and colorectal cancer were reported per study population.
RESULTS:
From 689 publications, 34 estimation methods were included. Five distinct types of mathematical estimation approaches were identified: prevalence-to-incidence ratio (n=8), maximum likelihood estimation (n=16), expectation-maximization algorithm (n=1), regression of observed on expected (n=6) and Bayesian Markov-chain Monte Carlo estimation (n=5). Fourteen studies used data from both screened and unscreened populations, whereas 19 studies included only information from a screened population. Estimates of the duration of the PCDP varied between 2 years and 7 years for breast cancer in the Health Insurance Plan study (annual mammography and clinical breast examinations in women aged 40-64 years) and 2 years and 5 years for colorectal cancer in the Calvados study (a guaiac fecal occult blood test in men and women aged 45-74 years).
CONCLUSIONS:
Different types of mathematical approaches lead to different estimates of the PCDP duration. We advise researchers to use the method that matches the data available, and to use multiple methods for estimation when possible, since no method is perfect.

Abstract: OBJECTIVES:
The aim of this study was to assess the impact of community water fluoridation (CWF) on differences in dental caries decline across racial and socioeconomic subgroups of Brazilian adolescents.
METHODS:
Two nationwide Brazilian population-based oral health surveys were used (Brazilian Oral Health Survey 2003 and 2010). In total, 7,198 adolescents from 15 years to 19 years old living in 50 cities investigated in both surveys were included. The mean numbers of untreated decayed teeth (DT) according to racial (Whites vs. Browns/Blacks) and socioeconomic subgroups (at or above the minimum wage per capita vs. under) were analysed. Difference-in-differences negative binomial regressions were adjusted by schooling, age, and sex. Decayed, missing, and filled teeth and DT prevalence, calculated as a categorical variable, were used in sensitivity analyses.
RESULTS:
The adjusted difference of reduction in DT was similar across socioeconomic subgroups (β=-0.05; 95% confidence interval [CI], -0.45 to 0.35) and favoured, but not to a significant degree, Whites (β=-0.34; 95% CI, -0.74 to 0.04) compared to Brown/Blacks in fluoridated areas. In non-fluoridated areas, significant differences were observed in the mean number of DT, favouring the higher socioeconomic subgroup (β=-0.26; 95% CI, -0.53 to -0.01) and Whites (β=-0.40; 95% CI, -0.69 to -0.11) in relation to their counterparts. The sensitivity analyses confirmed the findings.
CONCLUSIONS:
The similar reduction in DT across income subgroups suggests that CWF has had a beneficial effect on tackling income inequalities in dental caries within a 7-year timeframe.

COVID-19: Original Article Evidence of the importance of contact tracing in fighting COVID-19

Okyu Kwon Epidemiol Health. 2022;44:e2022006.

Original Article Association of participation in the Northern Finland Birth Cohort 1986 with mental disorders and suicidal behaviour

Martta Kerkelä, Mika Gissler, Juha Veijola Epidemiol Health. 2022;44:e2022005.

Abstract: OBJECTIVES:
We analyzed data to determine whether there are distinguishing characteristics depending on the success or failure of control for coronavirus disease 2019 (COVID-19) by country in the trend of the daily number of confirmed cases and the number of tests.
METHODS:
We obtained the number of confirmed cases and tests per day for almost every country in the world from Our World in Data. The Pearson correlation between the two time series was calculated according to the time delay to analyze the relationship between the number of tests and the number of cases with a lag.
RESULTS:
For each country, we obtained the time lag that makes the maximum correlation between the number of confirmed cases and the number of tests for COVID-19. It can be seen that countries whose time lag making maximum correlation lies in a special section between about 15 days and 20 days are generally been successful in controlling COVID-19. That section looks like a trench on the battlefield.
CONCLUSIONS:
We have seen the possibility that the success in mitigating COVID-19 can be expressed as a simple indicator of the time lag of the correlation between confirmed cases and tests. This time lag indicator is presumably reflected by efforts to actively trace the infected persons.

Abstract: OBJECTIVES:
In prospective follow-up studies, participants are normally contacted during the follow-up period. Even though the idea is not to intervene, the studies conducted during follow-up may affect the target population. Our hypotheses were that participation in the prospective Northern Finland Birth Cohort 1986 study (NFBC 1986) increased the use of mental health services and reduced suicidal behaviour due to participation in follow-up studies.
METHODS:
The NFBC 1986 study covered people with an expected date of birth between July 1985 and June 1986 in northern Finland (n=9,396). The participants of the NFBC 1986 were followed since the antenatal period with follow-ups including clinical examinations. The comparison cohort comprised people born in the same area in 1987 (n=8,959), who were not contacted. Registry data on psychiatric treatment, suicide attempts, and suicides were available. Crude risk ratios (RRs) and adjusted (for marital status and education) Mantel-Haenszel RRs were reported.
RESULTS:
No increase in mental disorders were found in NFBC 1986 compared to comparison cohort. In the crude RR analysis of female participants, a lower risk for suicide attempts was found (RR, 0.67; 95% confidence interval, 0.49 to 0.92; p=0.011).
CONCLUSIONS:
The results did not support our first hypothesis regarding the increased use of mental health services in the NFBC 1986 cohort. However, our second hypothesis gained some support as female participants of the NFBC 1986 had a lower risk of suicide attempts, although it was not due to a higher number of participants receiving psychiatric treatment.

COVID-19: Original Article Does having various types of fear related to COVID-19 disrupt individuals’ daily life?: Findings from a nationwide survey in Korea

Woorim Kim, Yeong Jun Ju, Soon Young Lee Epidemiol Health. 2022;44:e2022004.

Epidemiologic Investigation An outbreak of hepatitis A associated with salted clams in Busan, Korea

Hyunjin Son, Miyoung Lee, Youngduck Eun, Wonseo Park, et al. Epidemiol Health. 2022;44:e2022003.

Abstract: OBJECTIVES:
Unexpected changes in daily routines caused by the coronavirus disease 2019 (COVID-19) pandemic may affect psychological health. This study investigated the association between various types of COVID-19-related fear and the subjective level of disturbance in daily activities experienced by individuals.
METHODS:
This cross-sectional study used the Korea Community Health Survey conducted from August through November 2020. COVID-19-related fear included fear of infection, death, public criticism, family members getting infected, and economic loss. The subjective level of disruption in daily activities was measured using a 0-100 numeric rating scale developed by the Korea Disease Control and Prevention Agency. Multivariable linear regression was used to analyze the associations between the independent and dependent variables. A subgroup analysis was performed based on income level.
RESULTS:
Participants who reported fear of infection (β=-3.37, p<0.001), death (β=-0.33, p=0.030), public criticism (β=-1.63, p<0.001), a family member getting infected (β=-1.03, p<0.001), and economic loss (β=-3.52, p<0.001) experienced more disturbances in daily activities. The magnitude of this association was most significant in the lowest-income group.
CONCLUSIONS:
Individuals reporting COVID-19-related fear experienced higher levels of subjective disruption in daily activities.

Abstract: OBJECTIVES:
In July 2019, there were multiple reports on patients with hepatitis A among the visitors of a restaurant in Busan. The current study presents the results of an epidemiological investigation and outlines the supplementary measures that would help with hepatitis A control.
METHODS:
A cohort study was conducted for all 2,865 customers who visited restaurant A from June to July. Using a standardized questionnaire, participants reported the presence of hepatitis A symptoms and whether they had consumed any of 19 food items. As for participants who had visited public health centers, their specimens were collected.
RESULTS:
From the study cohort, 155 participants (5.4%) had confirmed hepatitis A. The epidemic curve was unimodal, and the median number of days from the restaurant visit to symptom onset was 31 days. A genotype analysis indicated that 89 of 90 tested patients had hepatitis A virus (HAV) genotype 1A. The results of a multivariate logistic regression analysis indicated that the ingestion of salted clams increased the risk of hepatitis A by 68.12 times (95% confidence interval [CI], 9.22 to 510.87). In an unopened package of salted clams found and secured through traceback investigation, HAV genotype 1A was detected.
CONCLUSIONS:
To prevent people from ingesting uncooked clams, there needs to be more efforts to publicize the dangers of uncooked clams; the food sampling test standards for salted clams should also be expanded. Furthermore, a laboratory surveillance system based on molecular genetics should be established to detect outbreaks earlier.

Original Article Age-specific effects of ozone on pneumonia in Korean children and adolescents: a nationwide time-series study

Kyoung-Nam Kim, Youn-Hee Lim, Sanghyuk Bae, In Gyu Song, et al. Epidemiol Health. 2022;44:e2022002.

Editorial Happy New Year 2022 from Epidemiology and Health (epiH)

Hyeon Chang Kim Epidemiol Health. 2022;44:e2022001.

Abstract: OBJECTIVES:
The aim of this study was to estimate the age-specific effects of 8-hour maximum ozone levels on pneumonia in children and adolescents.
METHODS:
We performed quasi-Poisson regression analyses for individuals of 0-4 years, 5-9 years, 10-14 years, and 15-19 years of age using nationwide time-series data from the Korea (2011-2015). We constructed distributed lag linear models employing a generalized difference-in-differences method and controlling for other air pollutants.
RESULTS:
A 10.0-parts per billion increase in 8-hour maximum ozone levels was associated with a higher risk of hospital admissions due to pneumonia at 0-4 (relative risk [RR], 1.02; 95% confidence interval [CI], 1.01 to 1.03) and 5-9 years of age (RR, 1.06; 95% CI, 1.04 to 1.08), but not at 10-14 (RR, 1.01; 95% CI, 0.98 to 1.04) or 15-19 years of age (RR, 1.01; 95% CI, 0.97 to 1.06). The association between ozone and hospital admissions due to pneumonia was stronger in cool seasons (from November to April) than in warm seasons (from May to October), but was similar between boys and girls.
CONCLUSIONS:
Short-term exposure to ozone was associated with a higher risk of pneumonia at 0-4 years and 5-9 years of age, but not at 10-14 years or 15-19 years of age. Our findings can help identify vulnerable periods, determine the target populations for public health interventions, and establish air pollution standards.

Abstract

Accepted Articles	Most Cited
Multimorbidity patterns by health-related quality of life status in older adults: An association rules and network analysis utilizing Korean National Health and Nutrition Examination Survey Thi-Ngoc Tran, Sanghee Lee, Chang-Mo Oh, Hyunsoon Cho Epidemiol Health. 2022;e2022113.	Mental health outcomes of quarantine and isolation for infection prevention: a systematic umbrella review of the global evidence Md Mahbub Hossain, Abida Sultana, Neetu Purohit Epidemiol Health. 2020;42:e2020038. Cited By 175
Mediation analysis of leisure activities on the association between cognitive function and mortality: longitudinal study of 42,942 Chinese adults 65 years and older Xingxing Chen, Xian Zhang, Tingxi Long, Wenfan Wu, Rundong Hu, Xurui Jin, Lijing L Yan, Yao Yao Epidemiol Health. 2022;e2022112.	Epidemiologic characteristics of early cases with 2019 novel coronavirus (2019-nCoV) disease in Korea Moran Ki, Epidemiol Health. 2020;42:e2020007. Cited By 136
Trends in breast cancer screening rates among Korean women: results from the Korean National Cancer Screening Survey (KNCSS), 2005-2020 Soo Yeon Song, Yun Yeong Lee, Hye Young Shin, Bomi Park, Mina Suh, Kui Son Choi, Jae Kwan Jun Epidemiol Health. 2022;e2022111.	WHO International Health Regulations Emergency Committee for the COVID-19 outbreak Youngmee Jee Epidemiol Health. 2020;42:e2020013. Cited By 124
Cause-specific mortalities in Korea during the first year of the COVID-19 pandemic Jinwook Bahk, Kyunghee Jung-Choi Epidemiol Health. 2022;e2022110.	Estimating the reproductive number and the outbreak size of COVID-19 in Korea Sunhwa Choi, Moran Ki Epidemiol Health. 2020;42:e2020011. Cited By 122
View more >	View more >