Risk of coronary heart disease events over 15 years among older adults with depressive symptoms

Abstract

Objectives: To determine whether depression status is associated with an increased risk of coronary heart disease (CHD) events, defined as CHD death or nonfatal acute myocardial infarction (MI).

Design: Prospective cohort study.

Setting: An urban primary care practice.

Participants: Two thousand seven hundred twenty-eight adults (71.4% women, 65.5% black), age 60 years and older, who were screened for depression between 1991 and 1993.

Measurements: Depressive symptom severity at baseline was assessed by the Center for Epidemiologic Studies Depression Scale (CES-D). Data regarding baseline demographic and clinical variables, as well as laboratory evidence of acute MI, were obtained from an electronic medical record system. All-cause mortality and CHD death were determined from the National Death Index through 2006.

Results: A total of 423 (15.5%) participants reported elevated symptoms of depression (CES-D score ≥16). During the 13 to 16 years of follow-up, 1,646 (60.3%) individuals died from any cause, and 727 (26.6%) died from CHD or suffered an acute MI. Cox proportional hazards models revealed that individuals with elevated depressive symptoms were more likely to experience a CHD event, even after adjustment for demographics and comorbid health conditions (relative risk = 1.46, 95% confidence interval: 1.20-1.77). Depression status was also a significant predictor of all-cause mortality in adjusted models.

Conclusions: We report the longest prospective study to date to examine depression status as an independent risk factor for CHD among a cohort of older adults including large numbers of women and underrepresented minorities. The present findings underscore the need to consider depression as a common and modifiable risk factor for CHD events among older adults.

Figure 1

Kaplan Meier survival curves (unadjusted) for time to acute myocardial infarction (MI) or coronary heart disease (CHD) death (panel A), CHD death (panel B), acute MI (panel C), and all-cause mortality (panel D) of depressed (dashed line) and non-depressed (solid line) individuals over the 15-year follow-up period.