BACKGROUND: Subclinical depression, often clinically unrecognized, may pose increased risk of cardiovascular disease. Few studies have prospectively investigated cardiovascular events related to depression in older women. We describe prevalence, cardiovascular correlates, and relationship to subsequent cardiovascular events of depressive symptoms among generally healthy postmenopausal women.

METHODS: The Women's Health Initiative Observational Study followed up 93 676 women for an average of 4.1 years. Depression was measured at baseline with a short form of the Center for Epidemiological Studies Depression Scale. Risks of cardiovascular disease (CVD) events were estimated from Cox proportional hazards models adjusting for multiple demographic, clinical, and risk factor covariates.

RESULTS: Current depressive symptoms above the screening cutoff point were reported by 15.8% of women. Depression was significantly related to CVD risk and comorbidity (odds ratios ranging from 1.12 for hypertension to 1.60 for history of stroke or angina). Among women with no history of CVD, depression was an independent predictor of CVD death (relative risk, 1.50) and all-cause mortality (relative risk, 1.32) after adjustment for age, race, education, income, diabetes, hypertension, smoking, high cholesterol level requiring medication, body mass index, and physical activity. Taking antidepressant medications did not alter the depression-associated risks associated.

CONCLUSIONS: A large proportion of older women report levels of depressive symptoms that are significantly related to increased risk of CVD death and all-cause mortality, even after controlling for established CVD risk factors. Whether early recognition and treatment of subclinical depression will lower CVD risk remains to be determined in clinical trials.