African Americans with major depressive symptoms -- perceived stress, neuroticism, life dissatisfaction -- had almost twice the increased risk of stroke and coronary heart disease, according to new research in the American Heart Association's journal Circulation: Quality and Outcomes.
While depression is recognized as a consequence of stroke and coronary heart disease, a common term for the buildup of plaque in the heart's arteries that could lead to heart attack, most studies have been conducted in white populations.
In this study, researchers used data from the Jackson Heart Study, a community-based study of African Americans in Jackson, Mississippi, that probed risk factors for heart disease. This analysis included 3,309 participants, ages 21 to 94, who completed at least 16 of 20 questions used to screen for depression. Those with a history of stroke or heart disease were excluded.
Of the 3,178 in the final analysis, over 22 percent had depressive symptoms at the start of the study. Those people also suffered from more chronic conditions, exercised less and garnered lower wages. They were more likely to be women, to be smokers and to have a higher body mass index.
"African Americans have higher rates of severe depression yet lower rates of treatment compared with white populations," said Emily O'Brien, Ph.D., lead researcher and medical instructor at the Clinical Research Institute at Duke University in Durham, North Carolina. "We need better communication between providers and patients to support early screening and shared-decision making to reduce the rate of depression in this population."
Annual telephone interviews with patients were conducted to determine the development of strokes or coronary heart disease as well as a review of hospital records and death certificates. All stroke or coronary heart disease events that took place over a 10-year period from the start of the study were included. They found:
- Increased risk of stroke for those with depressive symptoms (3.7%) compared with those with no depressive symptoms (2.6%)
- Increased risk of coronary heart disease for those with depressive symptoms (5.6%) compared with those without depressive symptoms (3.6%)
After adjusting for behavioral risk factors, antidepressant use and coping strategies, those with major depressive symptoms had twice the increased risk of stroke compared to those with no depressive symptoms. A similar association observed for coronary heart disease was not significant after adjusting for coping strategies.
"The need for greater understanding of associations between depressive symptoms and cardiovascular outcomes in African Americans is particularly important in light of reported racial disparities in disease severity, timely diagnosis, and use of drug therapy," O'Brien said.