Predictors of psychological and somatic components of poststroke depression: a longitudinal study.

PURPOSE: Depression after stroke is common and increases morbidity and mortality in the first years after stroke onset. Nevertheless, little is known about the role of psychosocial factors on the etiology of depression in early as well as in the late poststroke stages. The aim of our study was to investigate the influence of stroke survivors' mental impairment as well as the quality of their social relationships on the development of poststroke depression (PSD).
METHOD: The study used a longitudinal design. Eighty-one German stroke patients were investigated twice, directly after discharge (on the average of 3 months after stroke onset) and 1 year later. Hierarchical regression analyses and cross-lagged partial correlation analyses tested direct and indirect mediating effects of potential predictors on poststroke depressive symptoms.
RESULTS: Time 1 patients' perceived cognitive and emotional functioning predicted psychological depressive symptoms at Time 2. Quality of patients' social relationships mediated the effect of the stroke-related emotional deficits on depression.
CONCLUSION: In contrast to the previous research, the study provided more evidence for causal influence of different risk factors on PSD. Results support the biopsychosocial model of PSD. Early and late PSD seem to be based on partially different etiological mechanisms.