Trends in the Prevalence of Major Depressive Disorder by Sociodemographic Factors in Korea: Results from Nationwide General Population Surveys in 2001, 2006, and 2011

BACKGROUND: This study investigated trends in the prevalence of major depressive disorder (MDD) by sociodemographic factors in South Korea. METHODS: National samples of the general population aged 18 years or older collected from the nationwide Korean Epidemiologic Catchment Area surveys conducted in 2001 (n = 6,206), 2006 (n = 6,466), and 2011 (n = 5,986) were used. For MDD diagnosis, we conducted face-to-face interviews using the Korean version of the Composite International Diagnostic Interview. We performed logistic regression analyses stratified by gender, after adjusting for other sociodemographic variables, to calculate the 2006-to-2001 odds ratio (OR) and 2011-to-2001 OR by subgroups of sociodemographic factors to explore the association of MDD prevalence with sociodemographic factors over time. RESULTS: The prevalence of MDD in the general population of South Korea increased steadily from 2001, to 2006, and to 2011 (1.6%, 2.5%, and 3.1%, respectively). Among the men, the prevalence of MDD continued to increase significantly in 18–29 years of age group (2006: adjusted OR [AOR], 3.32; 2011: AOR, 7.42), at-risk drinking group (2006: AOR, 3.56; 2011: AOR, 4.77), and not living with a partner group (2006: AOR, 3.24; 2011: AOR, 3.25). Meanwhile, among the women, the prevalence of MDD continued to significantly increase in the below-average household income group (2006: AOR, 2.58; 2011: AOR, 2.59), at-risk drinking group (2006: AOR, 2.02; 2011: AOR, 2.47), and unemployed group (2006: AOR, 1.48; 2011: AOR, 2.04). CONCLUSION: This study may provide significant information for public policymakers to allocate sufficient health resources on MDD to vulnerable groups, particularly, men aged 18–29 years and women living in households with below-average income, and for clinicians to develop appropriate screening and treatment modalities for MDD.