Incidence of disability among preretirement adults: The impact of depression

Objectives. We evaluated the effect of depression on risk, on the basis of standardized assessment, for developing activities of daily living (ADL) disability. Methods. Depression-related risk on 2-year ADL disability is estimated from 6871 participants in a population-based national sample aged 54-65 years and free of baseline ADL disability. We evaluated the effects of factors amenable to clinical and public health intervention that may explain the relationship between depression and incident disability. Results. The odds of ADL disability were 4.3 times greater for depressed adults than their non-depressed peers (95% confidence interval = 3.1, 6.0). Among depressed adults, 18.7% of African Americans, 8.0% of Whites, and 7.8% of Hispanics developed disability within 2 years. The attributable population fraction because of depression is 17.3% (95% confidence interval = 11%, 24%). Concurrent health factors moderated depression-associated risk. Conclusions. Elevated risk of ADL disability onset because of depression, in a cohort whose medical costs will imminently be covered via Medicare, is attenuated by factors amenable to public health intervention. Prevention and/or public health/policy programs that lead to more accessible and effective mental health and medical care could reduce the development of ADL disability among depressed adults.