The impact of frailty on depressive disorder in later life: Findings from the Netherlands Study of depression in older persons

BACKGROUND: Physical frailty and depressive symptoms are reciprocally related in community-based studies, but its prognostic impact on depressive disorder remains unknown. METHODS: A cohort of 378 older persons (≥60 years) suffering from a depressive disorder (DSM-IV criteria) was reassessed at two-year follow-up. Depressive symptom severity was assessed every six months with the Inventory of Depressive Symptomatology, including a mood, motivational, and somatic subscale. Frailty was assessed according to the physical frailty phenotype at the baseline examination. RESULTS: For each additional frailty component, the odds of non-remission was 1.24 [95% CI=1.01-1.52] (P=040). Linear mixed models showed that only improvement of the motivational (P<001) subscale and the somatic subscale (P=003) of the IDS over time were dependent on the frailty severity. CONCLUSIONS: Physical frailty negatively impacts the course of late-life depression. Since only improvement of mood symptoms was independent of frailty severity, one may hypothesize that frailty and residual depression are easily mixed-up in psychiatric treatment.