Group-based trajectories of depressive symptoms and the predictors in the older population.

PURPOSE: The goals of this study were to examine the group-based trajectories of depressive symptoms over an extended period among the older people and to identify the risk factors by gender.
METHODS: The 18-year data used in this study came from a multiple-wave nationwide survey of older Taiwanese population. A group-based trajectory analysis method was used to identify the trajectories, and risk factors at baseline and previous depressive symptoms were used as predictors for the trajectories.
RESULTS: Six trajectories were identified within the total sample, and females were more likely to be in the increasing and declining trajectories than males. When the data were divided by gender, four trajectories for males and four trajectories for females were identified: low, medium, declining, and increasing. Higher-level trajectories of depressive symptoms were related to more chronic diseases, lower physical function, lower economic satisfaction, and previous depressive symptoms for both the older men and women. Less social support and social participation were related to higher depressive symptom trajectories, particularly for men. DISCUSSION: Older females may experience more emotional fluctuation than male elderly, thus changes in psychosocial health for female elderly need to be considered by health professionals and families. Social support and social participation are protective against depressive symptoms for the higher-level trajectory groups, and older men, in particular, are more sensitive to these two social-health-related variables.