REGARDS: Behavioral interventions beneficial for patients with CHD, depressive symptoms

In a recent study, behavioral interventions that target smoking and increased physical activity were associated with improved outcomes for patients with a history of CHD and symptoms of depression.

Researchers studied 4,667 participants with a history of CHD who participated in the population-based, longitudinal REGARDS study. The primary outcome was definite/probable MI or all-cause death.

At baseline, 13.6% of participants had elevated symptoms of depression, defined as a score of 4 or greater on the Center for Epidemiologic Studies Depression 4-item Scale. During a median of 3.8 years of follow-up, definite/probable MI or all-cause death occurred in 19.6% of patients with elevated depressive symptoms and 16.3% without symptoms.

Risk for MI/death was higher for elevated depressive symptoms after the researchers adjusted for demographics (HR=1.41; 95% CI, 1.15-1.72), but the same trend was not observed after adjustment for behavioral mechanisms (HR=1.14; 95% CI, 0.93-1.4). The four behavioral mechanisms studied were alcohol use, smoking habits, physical activity and medication nonadherence.

Together, the four behavioral mechanisms explained “a substantial proportion” of the heightened risk for MI/death associated with elevated depressive symptoms in these patients, according to the researchers. Smoking and physical inactivity were the biggest contributors, and accounted for 17.6% and 21%, respectively, of the relationship between risk for MI/death and elevated depressive symptoms.

“Our findings suggest potential roles for behavioral interventions targeting smoking and physical inactivity in patients with CHD and comorbid depression,” Siqin Ye, MD, from the Center for Behavioral Cardiovascular Health, Columbia University Medical Center, and colleagues wrote.

In an accompanying editor, James A. Blumenthal, PhD, from the department of psychiatry and behavioral sciences, Duke University Medical Center, said a lack of understanding of the association between depression and adverse outcomes is one barrier to the development of effective treatments for depression in patients with CHD.

“It has now become clear that depression is another of those characteristics that also increases the vulnerability of CHD patients to adverse events.

“[This report provides] support for the prognostic importance of elevated depressive symptoms in CHD patients. Moreover, by identifying smoking and physical inactivity as mediators of the relationship between depression and adverse health outcomes, they remind us of the value of promoting healthy lifestyle changes and specifically smoking cessation and exercise training to improve clinical outcomes in this vulnerable population,” Blumenthal wrote.

For more information:

Blumenthal JA. J Am Coll Cardiol. 2013;doi:10.1016/j.jacc.2012.11.029.

Ye S. J Am CollCardiol. 2013;doi:10.1016/j.jacc.2012.09.058.

Disclosure:Blumenthal reports no relevant financial disclosures. Monika M. Safford, MD, reports receiving salary support from Amgen and Pfizer and is a consultant for DiaDexus; Ye reports receiving grants from the NIH; all other researchers report no relevant financial disclosures.