August 1, 2002Open Access
Depression and mortality in a high-risk population
Key Result
Depression was associated with a 43% increased risk of mortality (HR 1.43) in older adults with moderate hypertension, independent of cardiovascular risk factors and cognitive decline.
Study Design
Type
Cohort (n=2,584)
Multicenter
Yes
PICO
P
Population
2,584 older adults aged 65-75 years with moderate hypertension, free of serious cardiovascular disease or dementia, followed for 11 years.
E
Exposure / Comparator
Depression vs No depression
O
Primary Outcome
Mortality — HR 1.43 (1.03-1.98), p=0.040
Main Result
Hazard Ratio: 1.43 (95% CI 1.03–1.98)
p-value: p=0.040
Limitations
- Restricted to a relatively healthy group, limiting generalisability to younger or normotensive populations.
- Smoking was coded only as a binary variable, which might lead to residual confounding.
- Depression was measured using a questionnaire rather than clinical interviews, potentially leading to misclassification.
- Unable to control effectively for exercise or alcohol intake.
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.