Differences in Depressive Symptom Profile by Age Group in Koreans With Major Depressive Disorder: Results From Nationwide General Population Surveys

Objective This study investigated to what extent a range of depressive symptoms was differentially present depending on age group in Korean population. Methods Data was pooled from five nationally representative surveys in which 29,418 respondents aged at least 18 years were interviewed face-to-face using the Korean version of the Composite International Diagnostic Interview. A total of 691 (2.1%) respondents were found to have had at least 1 episode of major depressive disorder (MDD) within the last 12 months. Logistic regression analysis was conducted to identify the association between age groups (18-39 years, 40-59 years, and 60 years or older) and 26 depressive symptoms among the respondents with MDD. Results Associations were observed between somatic symptoms-including insomnia, awakening 2 h earlier-and cognitive symptoms such as feelings of guilt, thoughts of death, and suicidal ideation with the older age group. Whereas, atypical depressive symptoms such as increased appetite, weight gain, and hypersomnia were associated with the younger age group. When adjusted for sociodemographic factors, symptoms such as depressed mood, awakening 2 h earlier, and feeling guilty in the older age group, and hypersomnia, psychomotor retardation, and worse in the morning in the younger age group still remained statistically significant. Furthermore, fatigue and decreased libido were newly associated with the younger age group. Conclusion The findings of this study revealed distinct patterns of symptomatology in MDD based on age groups. These differences should be considered owing to their potential relevance to treatment response and prognosis in the clinical setting.