Objective-Depression is a major contributor to death and disability, but few follow-up studies of depression have been carried out in the primary care setting. We sought to assess whether depression in older patients is associated with increased mortality after a 2-year follow-up interval and to estimate the population attributable fraction (PAF) of depression on mortality in older primary care patients.Method-Longitudinal cohort analysis carried out in 20 primary care practices. Participants were identified though a two-stage, age-stratified (60-74; 75+) depression screening of randomly sampled patients; enrollment included patients who screened positive and a random sample of screened negative patients. In all, 1226 persons were assessed at baseline. Vital status at 2 years was the outcome of interest.Results-Of 1226 persons in the sample, 598 were classified as depressed. After 2 years, 64 persons had died. Persons with depression at baseline were more likely to die at the end of the 2-year followup interval than were persons without depression (relative odds 1.81, 95% confidence interval [1.07, 3.05]; Wald χ 2 = 4.96, df = 1, p = 0.03), even after accounting for potentially influential covariates such as whether the participant reported a history of myocardial infarction (MI) or diabetes. We estimated the PAF due to depression on mortality to be 13%. By comparison, the PAF on mortality due to baseline report of MI was 11%; diabetes 9%; and any cardiovascular disease 18%.Conclusions-Among older primary care patients over the course of a 2-year follow-up interval, depression contributed as much to mortality as did MI or diabetes.