Ten-year trends in the prevalence and correlates of major depressive disorder in Korean near-elderly adults: a comparison of repeated nationwide cross-sectional studies from 2001 and 2011.

PURPOSE

Near-elderly adults go through many changes in socioeconomic status, such as retirement, which may affect their mental health differently according to when they live. We aimed to compare the prevalence of major depressive disorder (MDD) and its changes according to sociodemographic factors using nationally representative surveys of Korean near-elderly adults conducted 10 years apart.

METHODS

Nationwide community samples of individuals aged 55-64 years living in 2001 (n = 1256) and 2011 (n = 1066) were compared. Face-to-face interviews were conducted using the Korean version of the Composite International Diagnostic Interview to diagnose MDD. Sociodemographic data were collected using self-reported questionnaires including questions on employment and economic status. We examined differences in MDD prevalence and its association with sociodemographic factors over time by calculating 2011-to-2001 odds ratios (ORs) using multivariable logistic regression models.

RESULTS

Among near-elderly people, MDD tended to be more prevalent in 2011 than in 2001. However, only near-elderly men in 2011 showed a higher risk of MDD compared with those in 2001 (2011-to-2001 OR 4.19), while women did not. The prevalence ratio by gender decreased from 7.04 in 2001 to 2.34 in 2011. Among vulnerable sociodemographic groups, a significant increase in MDD was observed in unemployed men (adjusted OR 8.35), but not in unemployed women or other vulnerable groups.

CONCLUSION

This study provides evidence of a substantial increase in MDD in Korean near-elderly men and suggests that unemployment should be considered as an important correlate of MDD in this group.