Rate of stroke death after depression: a 40-year longitudinal study extension of Chichester/Salisbury Catchment area study.

Background: This study examined clinically diagnosed depression as a risk factor for incidence of death by stroke in a prospective clinically based design study. Risk for stroke was examined separately by sex in a long-term follow-up study spanning 40 years.

Methods: Patients who were diagnosed with depression in the Chichester (population 100,000)/Salisbury (population 85,000) Catchment Area Study were followed up for 40 years. Death certificates were used to determine the cause of death in the cohort. Death rates in the general population, adjusted for age, gender, and year, were used as a control.

Results: Clinical depression was found to be a risk factor for subsequent death from stroke in men but not in women. Death by stroke was a statistically significant cause of death in the men with diagnoses of endogenous depression but not in those men diagnosed with reactive depression. The strength of the relationship of depression with stroke increased over time.

Conclusions: These findings suggest that the identification of depressive symptoms at younger ages may have an impact on the primary prevention of stroke in later life. The notion that depression has stronger effects over a long period is consistent with a view that severe clinical depression and physical illness occur concurrently, one exacerbating the other, and health is degraded through slow-acting, cumulative processes. Data were unavailable for the type of stroke or the health-risk behaviors (smoking, diet, and so forth) in the cohort which constituted a limitation of the study. Neither is it known what proportion of the cohort suffered a nonlethal stroke nor to what extent the treatment of clinical depression militates against suffering a lethal stroke.