Abstract
PURPOSE: The aim was to identify high-risk groups for postretirement depression among those aged 65 or older. METHODS: This study used the 9th Korean Longitudinal Study of Ageing to identify the prevalence of depression among 1,879 retirees aged 65 and above and to develop a predictive model. The decision-tree-analysis method was used to construct a predictive model. RESULTS: The highest proportion of depression, at 58.5%, was observed in males who do not engage in regular exercise and have low daily living performance. In the predictive model where age is fixed as the first branch, depression was highest at 55.4% among middle-old or old-old individuals with low oral-health-related quality of life and marital status of separated/divorced/widowed/never married. In a predictive model that first classifies by sex, the proportion of depression was highest at 53.7% for dependent males. CONCLUSION: This study confirmed that age, oral health, marital status, heath status, instrumental activities of daily living, activities of daily living, and regular exercise have an impact on depression. However, these factors change over time, so longitudinal studies should be conducted to understand how depression changes with them.