The aim of this study was to investigate the prevalence and correlates of depressive symptoms in the largest number of Korean individuals examined to date. We analyzed cross-sectional data collected from 229,595 Korean adults aged 19 yr and above who participated in a Korean Community Health Survey conducted in 2009. The Center for Epidemiologic Studies Depression Scale (CES-D) was used as the measurement tool for depressive symptoms (CES-D score over 16) and definite depression (CES-D score over 25). Multivariate logistic regression analysis was performed to identify associations between sociodemographic factors and depressive symptoms. The percentages of depressive symptoms and definite depression in the total study population were 11% (7.8% for men, 14.0% for women) and 3.7%, (2.4% for men, 5.0% for women), respectively. Female gender, older age, disrupted marital status, low education and income level, multigenerational household composition and metropolitan residence were associated with greater risk of depressive symptoms. The present study provides a valid prevalence and correlates of depressive symptoms, using the largest representative sample of the Korean general population to date. Various sociodemographic factors contribute to the prevalence and effects of depressive symptoms in Korea.

BackgroundThe purpose of this study was to investigate the relationship between multiple chronic diseases and depressive symptoms in middle-aged and elderly populations.MethodsThis study was performed using the 2009 Korean Community Health Survey, which targeted adults over the age of 40 (N = 156,747 participants, 88,749 aged 40–59 years and 67,998 aged ≥60 years). The Korean version of the Center for Epidemiologic Studies Depression Scale (CES-D-K) was used as the measurement tool for depressive symptoms (CES-D-K score over 16). Multiple chronic diseases were defined as the concurrent presence of two or more chronic diseases.ResultsThe prevalence and risk ratios (RRs) of experiencing depressive symptoms increased in the presence of multiple chronic diseases and with the number of comorbidities. The RRs of experiencing depressive symptoms according to the presence of multiple chronic diseases were higher in the middle-aged population (adjusted RR, 1.939, 95% confidence limits (CL), 1.82-2.06) than in the elderly population (adjusted RR, 1.620, 95% CL, 1.55-1.69). In particular, middle-aged women who suffer from 4 or more chronic diseases have the highest RR (adjusted RR, 4.985, 95% CL, 4.13-6.03) for depressive symptoms.ConclusionsMultiple chronic diseases are closely associated with depressive symptoms in middle-aged and elderly populations. Given the mutual relationship between multiple chronic diseases and depressive symptoms, attention to and the assessment of depressive symptoms are needed in people with multiple chronic diseases.Electronic supplementary materialThe online version of this article (10.1186/s12889-017-4798-2) contains supplementary material, which is available to authorized users.

Objectives Over the past several years, the incidence of hepatitis A infection has been increasing rapidly in the young-adult population in Korea. We examined the effects of area-level socioeconomic status and environmental hygiene on the incidence of hepatitis A. Methods This study is based on the registered national population of Korea and the national health insurance data from 2004 to 2008. A total of 73 459 individuals were confirmed to have had hepatitis A. The standardized incidences of hepatitis A in 232 districts adjusted for sex and age of people were calculated for each year, and the rate ratios of the incidence rates were estimated according to area-level socioeconomic status and environmental hygiene using multiple Poisson regression models. Results The incidence rates of hepatitis A infection were 15.6 (per 100 000) in 2004, 19.0 (per 100 000) in 2005, 27.2 (per 100 000) in 2006, 25.1 (per 100 000) in 2007, and 61.7 (per 100 000) in 2008. The analysis of the area-level effects showed that residential areas of the less deprived than other regions, areas with higher levels of education, and heavily populated areas were significantly associated with increased risk. Conclusions There is a very strong possibility that both area-level socioeconomic status and environmental hygiene play a role in increasing the risk of hepatitis A infection in Korea. Therefore, to reduce hepatitis A infection, we need a nationwide strategy that considers these area-level characteristics.

This study aimed to identify the risk factors associated with acute hepatitis A virus (HAV) infection in the Korean population. Participants were recruited from five referral hospitals across the country in 2007 and from 11 hospitals in 2009. Patients with positive anti-HAV IgM antibody tests became the case group, while patients treated for non-contagious diseases at the same hospitals were recruited as controls. A total of 222 and 548 case-control pairs were studied in the 2007 and 2009 surveys, respectively. Data from the surveys were analyzed jointly. In a multivariate analysis, sharing the household with HAV-infected family members (OR, 6.32; 95% CI, 1.4-29.6), contact with other HAV-infected individuals (OR, 4.73; 95% CI, 2.4-9.4), overseas travel in 2007 (OR, 19.93; 95% CI, 2.3-174.4), consumption of raw shellfish (OR, 2.51; 95% CI, 1.8-3.5), drinking bottled water (OR, 1.64; 95% CI, 1.3-8.4), and occupation that involve handling food (OR, 3.30; 95% CI, 1.3-8.4) increased the risk of HAV infection. Avoiding contact with HAV-infected individuals and avoiding raw foods eating could help minimize the risk of hepatitis A infection. Immunization must be beneficial to individuals who handle food ingredients occupationally or travel overseas to HAV-endemic areas.

Microalbuminuria is a marker of generalized endothelial dysfunction resulting from arterial stiffness or insulin resistance, and brachial-ankle pulse wave velocity (baPWV) is a good measure of arterial stiffness. We aimed to investigate whether elevated baPWV is independently associated with microalbuminuria. This study included 1,648 individuals aged over 40 who participated in the baseline Multi-Rural Cohort Study conducted in Korean rural communities between 2005 and 2006. Participants were classified into less than 30 mg/g as normoalbuminuria or 30-300 mg/g as microalbuminuriausing urinary albumin creatinine ratio (UACR). The median and Q1-Q3 baPWV values were significantly higher in the microalbuminuric group both in men (1,538, 1,370-1,777 cm/s vs. 1,776, 1,552-2,027 cm/s, P < 0.001) and women (1,461, 1,271-1,687 cm/s vs. 1,645, 1,473-1,915 cm/s, P < 0.001). BaPWV was independently associated with microalbuminuria in both genders after adjusting for pulse rate; fasting blood glucose; triglyceride; homeostatic model assessment insulin resistance (HOMAIR) and, history of hypertension and diabetes. Fasting blood sugar and HOMAIR were judged as having nothing to do with multicolinearity (r = 0.532, P < 0.001). Elevated baPWV was independently associated with microalbuminuria regardless of insulin resistance among rural subjects over 40 yr.Graphical Abstract