Risk Factors for Major Depression in Older Medical Inpatients: A Prospective Study

Abstract

To determine risk factors for major depression in older medical inpatients. In a prospective cohort study, 86 older medical inpatients without depression or antidepressant medication were assessed 3, 6, and 12 months after enrollment. Incident major depression was diagnosed using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria. Potential predictive variables included sociodemographic variables, physical state, cognition, depressive symptoms, medication use, prior depressive episode, social network, support, and bereavement. Cox proportional hazards analysis (with backward variable elimination) was used to determine the best set of predictors. Twenty-six patients (30.2%) met criteria for incident major depression. Predictors of major depression included the following: prior depressive episode, birth outside Canada, low comorbidity, inadequate emotional support, fewer children seen, depressed mood, and diurnal variation. The risk of depression increased with the number of risk factors present. The seven identified risk factors may guide efforts to prevent major depression in older medical inpatients.