Background: Heart disease continues to be a notable cause of morbidity and mortality worldwide. In many developed countries, cardiac-related mortality has decreased in recent decades. However, morbidity has increased because more patients survive their initial cardiac event. Cardiac rehabilitation after myocardial infarction or revascularization improves physical health and reduces cardiac-related morbidity and mortality. These programs usually include exercise, education, counseling, and support, and offer strategies to change patient behaviors to modify cardiac risk factors. Two recent randomized controlled trials reported a 20 percent reduction in all-cause mortality and a 27 percent reduction in cardiacrelated mortality for participants at two to five years.

Despite the effectiveness of cardiac rehabilitation programs, participation is low, with patients citing program access difficulties, dislike of groups, and time conflicts with work and home responsibilities. A small systematic review comparing home- and center-based rehabilitation programs found no difference in effectiveness, but two large randomized controlled trials have been published since that review was completed. Dalal and colleagues provided an updated systematic review of the effects of home- versus center-based cardiac rehabilitation on morbidity, mortality, health-related quality of life, and modifiable cardiac risk factors in patients who have had a cardiac event.

The Study: Trials were identified from the previously published systematic review and by additional literature searches of clinical databases, including the Cochrane Central Register of Controlled Trials, Medline, EMBASE, CINAHL, and PsycINFO. Studies were eligible if they included patients who had participated in, or had been invited to participate in, formal cardiac rehabilitation following myocardial infarction, angina, heart failure, or revascularization (i.e., coronary artery bypass grafting, percutaneous transluminal coronary angioplasty, or coronary artery stenting). Studies involving patients with heart transplants, cardiac resynchronization devices, or implantable defibrillators were excluded. Home-based rehabilitation was defined as a structured program that included clear objectives and incorporated regular monitoring and follow-up. Center-based rehabilitation included supervised group programs, usually located at hospitals or sports centers.

Results: This review included 12 studies and 1,938 participants: three studies from the United Kingdom; four from the United States; and one each from Canada, Turkey, Italy, Iran, and China. Of these trials, nine reported outcomes up to 12 months; the remainder had follow-up for 14 to 24 months. The programs varied in content and intensity; eight programs included exercise with education or counseling and four reported only on exercise. The center-based programs used treadmills or bicycles for exercise, and the home-based programs were based on walking protocols. Most studies recruited patients at low risk of subsequent events.

After accounting for study heterogeneity, the authors found no significant differences between home- and center-based cardiac rehabilitation on all-cause or cardiac-related mortality, morbidity, short-term exercise capacity, blood pressure, smoking cessation, or health-related quality of life measures. The cost for each type of program depended on the health care economy of each country; there were no notable cost differences between home- and center-based care.

Conclusion: The authors conclude that structured cardiac rehabilitation programs are effective for secondary prevention in patients with a low risk of further cardiac events. Home-based programs are as effective as center-based programs.

editor's note: An accompanying editorial highlights the potential advantages of developing evidence-based, structured, home-based cardiac rehabilitation programs, including increased access and improved adherence to lifestyle modifications.1 The author notes that health behaviors must be sustained for at least two years to improve morbidity and mortality, whereas the usual duration of center-based programs is two to three months. Establishing the patient's home as the site for long-term health changes provides continuity and the opportunity for family support, and is always available; even in high-income countries such as Australia and Canada with universal and free cardiac rehabilitation, much of the population has limited access to center-based programs. Additionally, groups least likely to use center-based programs, including older adults, women, persons of different ethnic groups, and persons of low socioeconomic status, are among those at greatest need for secondary prevention.

The author cautions that although home-based programs can potentially expand access to cardiac rehabilitation, all protocols are likely not equally effective.¹ This study did not adequately explore how individual components of the programs affected outcomes. Future research needs to include more comprehensive descriptions of individual programs and better attention to the care given in intervention and control groups.—a.c.f.