Depression and mortality in a high-risk population. 11-Year follow-up of the Medical Research Council Elderly Hypertension Trial

Abstract

Background: It is not clear whether the increased mortality associated with depression can be explained by the effects of potential confounding variables.

Aims: To measure the effect of depression on mortality after controlling for cognitive decline, cardiovascular risk factors and antidepressant use.

Method: A prospective cohort study derived from data from a multi-centre randomised controlled trial of moderate hypertension. A total of 2584 participants, aged 65-75 years at study entry, were followed up for 11 years.

Results: Depression on the SelfCARE-D scale was associated with mortality after controlling for gender. After controlling for cardiovascular risk factors, cognitive decline and antidepressant use, depression continued to have a modest effect (hazard ratio=1.43; 95% C11.03-1.98). Depression in males and in people aged under 70 years significantly increased the risk of death.

Conclusions: Depression was associated with mortality only after controlling for gender. There was a modest but robust association between depression and mortality that was not explained by confounding by cardiovascular risk factors, cognitive decline or history of antidepressant use.