Atypical epidemiologic finding in association between depression and alcohol use or smoking in Korean male: Korean longitudinal study of aging

Objective The purpose of this study is to examine the relationship between substance use and depressive symptoms in a cohort of Koreans aged 45 years and older from a large, population-based study. Using the 2006 Korean Longitudinal Study of Aging, we estimated the prevalence of depressive symptoms and its association with smoking and alcohol use. Methods Depressive symptoms were measured using the CES-D 10-item scale. Age, marital status, educational attainment, employment and any disability were the control variables. Because there were gender differences in smoking and alcohol use, we also performed a separate analysis by gender. Results In the multivariable logistic regression, ex-drinkers were more likely to be depressed than non-drinkers (OR, 1.37; 95% CI, 1.08-1.74 for males; OR, 1.78; 95% CI, 1.23-2.57 for females). Compared to non-drinkers, males with moderate drinking habits (OR, 0.75; 95% CI, 0.63-0.90) were less likely to be depressed, whereas heavy male drinkers were more likely to be depressed (OR, 1.43; 95% CI, 1.07-1.91). Female smokers were more likely to be depressed than female non-smokers (OR, 2.07; 95% CI, 1.51-2.83). Conclusion This study showed atypical pattern of relationship between smoking and depression and U-shaped relationship between depressive symptoms and alcohol consumption in male population. Both of these findings could be inferred from that these regional characteristics might be cross-sectional finding of chronologic transition result from a rapid rise of late life depression in Korea.