Prevalence and correlates of depressive symptoms in a catchment-area based cohort of older community-living schizophrenia patients.

Background: Depressive symptoms frequently accompany schizophrenia. Older patients constitute the fastest growing segment of the schizophrenia population. With regard to the risk factors associated with depression, it is uncertain to which extent older schizophrenia patients differ from their age peers in the community.

Methods: We assessed self-reported depressive symptoms in an epidemiological sample of older Dutch community-living patients with schizophrenia or schizoaffective disorder (N=99; mean age 67years). Demographic, clinical and social variables were evaluated for their predictive value on the level of depressive symptoms. A comparison group, proportionally matched for age and gender, was recruited from a community study.

Results: In the schizophrenia group, 47.5% reported depressive symptoms at a level indicating clinically relevant depression, in contrast to 12.1% in their age peers (odds ratio 6.55; 95% CI, 3.19-13.48; p<0.001). This difference could not be explained by differential exposure to the evaluated general risk factors. In both groups, functional limitations were the strongest predictor of depressive symptoms. In the patient group, chronic physical disorders and lack of a confidant were predictors, while a diagnosis of schizoaffective disorder (vs. schizophrenia) was the only disorder-related risk factor that contributed to depressive symptoms, with marginal significance.

Conclusion: The high rate of depressive symptoms in this epidemiological sample of older schizophrenia patients confirms that these symptoms frequently accompany this severe mental illness in late life. With physical and social factors as important predictors of depressive symptoms, risk factors for depression are more comparable between older schizophrenia patients and their age peers than is often assumed.