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Exercise Benefits Patients With Chronic Heart Failure

Regular exercise is safe for heart failure patients, improves their quality of life and may slightly lower their risk of death or hospitalization, according to a new study.

About 5 million people nationwide have heart failure, a potentially life-threatening condition in which the heart has a reduced ability to pump blood through the body. It is the leading cause of hospitalization among Americans age 65 and older, and the numbers are growing. Each year, another 550,000 people are diagnosed for the first time.

Heart failure usually develops over several years, most commonly as a result of coronary artery disease, high blood pressure or diabetes. Treatment typically includes lifestyle changes, medicines and regular outpatient follow-up with a health care provider. Some patients also need medical devices to help the heart pump better, or surgeries, such as a coronary artery bypass operation or heart transplant.

Previous, smaller clinical trials have suggested that exercise training is beneficial for heart failure patients. Clinical guidelines currently recommend moderate physical activity for the condition. However, many doctors and their chronic heart failure patients remain concerned about the risks of exercise. To investigate, researchers supported by NIH's National Heart, Lung and Blood Institute (NHLBI) launched a comprehensive clinical trial at 82 centers in the United States, Canada and France.

The researchers followed over 2,300 patients with systolic heart failure (average age 59) for an average of 2.5 years and up to 4. About half the participants were randomly assigned to receive usual care. They were also asked to engage in 30 minutes of moderate physical activity on most days of the week.

The other half received usual care plus 36 sessions of group-based, supervised aerobic exercise training (walking or stationary cycling) of up to 35 minutes, 3 times per week. They were then asked to exercise at home 5 times per week for the remainder of the study. To help, they were given a treadmill or stationary bike and a heart rate monitor.

The results appeared in 2 papers in the April 8, 2009, issue of the Journal of the American Medical Association. Compared to the usual care group, the exercise training group had slightly fewer deaths or hospitalizations, but the difference wasn't large enough to prove it wasn't due to chance. However, when the researchers assessed the strongest predictors of death or hospitalization, they found that exercise training lowered the risk of all-cause death or hospitalization by 11% and lowered the risk of cardiovascular-related death or hospitalization for heart failure by 15%.

Participants in the exercise group also scored significantly higher within 3 months—and throughout the study—on a quality-of-life questionnaire. They reported fewer symptoms and physical or social limitations. In addition, the study found exercise training to be well tolerated and safe.

“Many patients and healthcare providers have continued to be concerned about the safety of aerobic exercise for heart failure," said NHLBI Director Dr. Elizabeth G. Nabel. "With the results of this robust clinical trial, we can now reassure heart failure patients that, with appropriate medical supervision, regular aerobic exercise is not only safe but it can also improve their lives in really meaningful ways.”