Among people with coronary disease, symptoms of depression are strongly associated with perceptions of poorer overall health independently of quantitative clinical measures such as ejection fraction, according to an article in the July 9th issue of the Journal of the American Medical Association.

According to background information provided by the authors, "in patients with coronary disease, cardiovascular interventions are known to improve health status, but the extent to which such benefits result from changes in cardiac versus noncardiac factors is unclear. Depressive symptoms are known to be associated with worse health status among patients with coronary artery disease, but their relative contributions compared with physiologic measures of disease severity are unknown."

Bernice Ruo, M.D., and her American colleagues conducted a study of 1,024 adults with stable coronary artery disease recruited from outpatient clinics in an urban community between September 2000 and December 2002 to compare the contributions of depressive symptoms and cardiac function to patient-reported health status. Participants completed a daylong baseline study appointment that included a medical history interview, a physical examination, an exercise treadmill test with a stress echocardiogram, and a comprehensive health status questionnaire.

"Of the 1,024 participants, 201 (20 percent) had depressive symptoms," the authors reported. "Participants with depressive symptoms were more likely than those without depressive symptoms to report at least mild symptom burden (60 percent versus 33 percent), mild physical limitation (73 percent versus 40 percent), mildly diminished quality of life (67 percent versus 31 percent), and fair or poor overall health (66 percent versus 30 percent). Compared with participants who did not have depressive symptoms, those with depressive symptoms were younger, had lower income, and were less likely to be male or married. They were more likely to have a history of myocardial infarction or diabetes mellitus, to smoke, and to report greater stress and worse social support. Participants with depressive symptoms had higher body mass index and lower exercise capacity." The authors added that cardiac function itself was not affected by depressive symptoms.

The authors concluded, "In summary, we found that depressive symptoms, a modifiable risk factor, are strongly associated with symptom burden, physical function, disease-specific quality of life, and perceived overall health among patients with coronary disease. In contrast, two traditional measures of disease severity - ejection fraction and ischemia - were not associated with health status outcomes. Future efforts to improve the health status of patients with coronary artery disease should include a focus on depressive symptoms."