Chicago, IL - Getting more exercise and learning how to manage stress not only helps people with ischemic heart disease (IHD) deal with depression and emotional distress but can also have a positive impact on CV risk factors, a new randomized study suggests. Investigators say that compared with IHD patients whose disease was monitored only by routine medical care, patients participating in supervised aerobic exercise or regular stress-management training experienced improved "psychological functioning" as well as smaller reductions in left ventricular ejection fraction, better vascular function, and improved responses to blood-pressure changes when exposed to psychological or physical stressors.

"There have been a number of studies that have looked at the association of stress and various end points, like MI or death, or even some of these markers," first author Dr James A Blumenthal (Duke University, Durham, NC) told heartwire. "What hasn't been shown is that changing our reactions to stress has any significant impact on important health outcomes. This sounds kind of simplistic and maybe a little bit trite, but I think it emphasizes the importance of incorporating these treatment approaches in the regular management of cardiac patients."

The study results appear in the April 6, 2005 issue of the Journal of the American Medical Association.[1]

The authors acknowledge that the value of modifying psychosocial risk factors as a means of reducing cardiac risk remains controversial, largely due to the failure of large, randomized trials to demonstrate measurable effects of psychosocial interventions on cardiac morbidity and mortality. But, Blumenthal et al note, most studies also failed to adequately reduce the psychosocial risk factors themselves.

This sounds kind of simplistic and maybe a little bit trite, but I think it emphasizes the importance of incorporating these treatment approaches in the regular management of cardiac patients.

In the current study, the investigators randomized 134 IHD patients to usual care or a thrice-weekly exercise program or a once-a-week stress-management program on top of usual care for four months. They found that compared with people in the usual-care group, people in the exercise and stress-management groups had significantly reduced depression and general distress, as measured by validated tests (the General Health Questionnaire [GHQ] and Beck Depression Index [BDI], respectively). Participants also underwent a series of cardiovascular exams following interventions designed to induce mental stress or after exercising to exhaustion. In both settings, participants in the two test groups appeared to fare better than IHD patients with no stress or exercise training.

In a subset of patients, Blumenthal et al measured heart-rate variability and baroreflex sensitivity, noting that patients who underwent stress management appeared to have improved heart-rate variability on deep-breathing tests, as well as significantly improved baroreflex sensitivity, compared with usual-care patients.

"The group who underwent stress-management training had significant improvements in those markers that really reflect how well the cardiovascular system buffers itself against surges in blood pressure," Blumenthal told heartwire. "In fact, the stress-management group did better than the exercise group did, which was surprising. We thought this was a very interesting observation; it was unexpected, and it's never been shown before."

The authors found no significant differences between the exercise or stress-management groups, with the exception of aerobic fitness, in which trial participants in the exercise group did significantly better than the usual-care group in a treadmill test, whereas those in the stress-management group performed no better than the usual-care group.

Blumenthal et al point out that although depressive symptoms and emotional stress are associated with adverse CV events, improvements in these areas have not previously been shown to diminish CV risk. The current study was not powered to look at hard clinical end points but does at least show improvement in several cardiovascular risk markers.

They believe that their study, while small, with limited follow-up, does at least suggest mechanisms by which improved ability to cope with physical and mental stressors can help diminish cardiovascular risk.

Of note, the study did not specifically enroll patients with depression or who acknowledged suffering from stress and anxiety, yet the study participants nevertheless "clearly benefited from these types of behavioral programs," Blumenthal emphasized.

He points out that most cardiac rehabilitation programs have some sort of stress-management component (in addition to exercise programs) but that rehab programs are generally underutilized, with only 10% to 30% of eligible participants actually engaging in cardiac rehabilitation.

Physicians are partly to blame, Blumenthal notes. "Most doctors would say, okay, let's take a look at your blood pressure and your lipids, and we want you to stop smoking, but in terms of these other aspects, I don't think physicians are as convinced that they are important. Also, physicians are not necessarily equipped to do something about stress management. And if physicians aren't trained to intervene, they are less likely to recommend it."

This study helps bolster the evidence that nonpharmacologic approaches have value over and above standard medical therapy, he says. "We're not saying that these interventions should replace medical therapy, but they can enhance the benefits of those more traditional approaches."