This study aimed to identify the longitudinal pattern changes of South Koreans' midlife depression and determine the impact of socioeconomic deprivation on the observed change in patterns. In total, 3975 middle-aged individuals were examined by conducting a latent class growth analysis and multinomial logistic regression analysis on seven years of Korea Welfare Panel data (2012-2018) using STATA 16.0 (StataCorp LLC, College Station, TX, USA). The change patterns of midlife depression were classified into normal depression reduction group, mild depression maintenance group, and serious depression increase group. The impact of the experience of socioeconomic deprivation on the classified change patterns was examined using the normal depression reduction group as the reference group. It was found that the higher an individual's nutritional, housing, occupational/economic, and healthcare deprivation, the higher their risk of mild depression maintenance or serious depression increase. The serious depression increase group showed higher relative risk ratios in all domains. Comprehensive and integrated social welfare services, such as stable income, housing welfare, and healthcare services, should be provided along with appropriate clinical interventions for depression alleviation that account for the pattern changes in midlife depression.
Keywords: a latent class growth analysis; longitudinal change patterns; middle-aged Koreans; midlife depression; socioeconomic deprivation.