Trajectories of depression and their relationship with health status and social service use.

This longitudinal study was conducted between 1994 and 2004 in a cohort of Southern Taiwan community-living elderly residents. The study aims to explore the trajectories of depression and how these patterns differed between respondents who survived and those who died during data collection phases; this study also investigated how health status change and health/social service use predicted the different trajectories of depression. Eight hundred and ten participants had completed all six waves of the survey or were followed-up at each wave until death in the prospective study in Kaohsiung City. Depressive symptoms were evaluated by the Short Psychiatric Evaluation Schedule (SPES). Changes in levels of depression during the ageing process were identified. Different trajectories clearly reflected heterogeneity within depression and the association with mortality. The study highlighted that diabetes, gastrointestinal problems, heart disease and disability, whether at baseline or as new occurrences, were predictors of health decline. High uses of health/social services were also predictive of increased depression. These findings identified depression as a highly dynamic process, characterized by different trajectories of depression between states of no, mild and severe depression. Greater awareness of these various trajectories should potentially improve the prevention and/or management strategies of depression.