Antidepressant treatment results in lower rate of MSIMI

Among patients with stable coronary heart disease and mental stress-induced myocardial ischemia (MSIMI), 6 weeks of treatment with the antidepressant escitalopram, compared with placebo, resulted in a lower rate of MSIMI, according to a study in the May 22/29 issue of JAMA.

"A robust body of evidence has identified emotional stress as a potential triggering factor in coronary heart disease (CHD) and other cardiovascular events," according to background information in the article. "During the last 3 decades, the association of emotional distress and myocardial ischemic activity [insufficient blood flow to the heart muscle, often resulting in chest pain] in the laboratory has been well studied. In the laboratory setting, MSIMI occurs in up to 70 percent of patients with clinically stable CHD and is associated with increased risk of death and cardiovascular events." Few studies have examined therapeutics that effectively modify MSIMI. Recent evidence suggests that selective serotonin reuptake inhibitors (SSRIs) may reduce mental stress-induced hemodynamic response, metabolic risk factors, and platelet activity.

Wei Jiang, M.D., of the Duke University Medical Center, Durham, N.C., and colleagues conducted a study to investigate whether SSRI treatment can improve MSIMI. The randomized trial included patients with clinically stable coronary heart disease and laboratory-diagnosed MSIMI. Enrollment occurred from July 2007 through August 2011 at a tertiary medical center. Eligible participants were randomized 1:1 to receive escitalopram or placebo over 6 weeks. A total of 56 patients in each group completed end point assessments. Occurrence of MSIMI was defined via various measures during 1 or more of 3 mental stressor tasks: mental arithmetic, mirror trace, and public speaking with anger recall.

The researchers found that at the end of 6 weeks, more patients taking escitalopram (34.2 percent) had absence of MSIMI during the 3 mental stressors compared with patients taking placebo (17.5 percent). Analysis showed that the escitalopram group had a significantly higher rate (2.6 times) of no MSIMI compared with the placebo group. Also, hemodynamic responses to mental stress were all lower in the escitalopram group, with differences in systolic blood pressure and heart rate between the groups significant.

In addition, the 6-week escitalopram intervention was associated with greater improvements in certain measures of psychological functioning, including state anxiety and positive affect, during mental stress.

Exercise capacity was not significantly altered at week 6 in participants receiving escitalopram vs. those receiving placebo.

"In summary, 6-week pharmacologic enhancement of serotonergic function superimposed on the best evidence-based management of CHD appeared to significantly improve MSIMI occurrence. These results support and extend previous findings suggesting that modifying central and peripheral serotonergic function could improve CHD symptoms and may have implications for understanding the pathways by which negative emotions affect cardiovascular prognosis," the authors conclude.

Source: Duke University Medical Center