Cardiac Rehab Offers Longer Life to Heart Attack Survivors
|
|
Cardiac rehabilitation programs give many heart attack survivors better, longer lives, regardless of whether the programs include supervised exercise.
That is the major finding of researchers here, who pooled data from 63 studies of cardiac rehabilitation or secondary prevention programs into a meta-analysis, which was published in the Nov. 1 Annals of Internal Medicine.
Taken as a whole, the programs reduced the risk of a second myocardial infarction within the first year by 17%, and all-cause mortality by nearly 50% two years after a first heart attack, reported Alexander M. Clark, Ph.D., and colleagues at the University of Alberta Evidence-Based Practice Center.
The benefits of various programs—including counseling about coronary risk factors, dietary changes, lipid and blood pressure management, smoking cessation, and supervised exercise programs—were similar, irrespective of whether the program consisted of risk-modification alone, risk-modification plus exercise, or exercise alone, the authors found.
“Since exercise training confers substantial psychological benefits and activity levels are inversely proportional to cardiovascular mortality, it is not surprising that trials of exercise programs found positive effects on survival,” Dr. Clark and colleagues wrote.
What’s less clear, however, was whether programs focused on modification of other coronary heart disease risk factors could offer benefits similar to those conferred by exercise in terms of survival, quality of life, and health care costs.
To dissect the answers, the meta-analysis included a total of 21,295 patients with coronary disease. The studies were grouped into those examining risk factors modification with and without an exercise component, and supervised exercise programs alone.
The investigators found that the summary risk ratio for all-cause mortality was 0.85 (95% confidence interval, 0.77 to 0.94), ranging from 0.97 (95% CI 0.82 to 1.14) at one year to 0.53 (95% CI, 0.35 to 0.81) at two years.
When considering possible reasons for the lack of a significant reduction in mortality risk at one year, the authors suggested that “12 months is probably too short to show a clear effect on mortality given the natural history of atherosclerotic coronary artery disease (that is, changes in coronary risk factors would not be expected to produce immediate improvements in atherosclerotic plaque stability or coronary artery diameter).”
Alternatively, the patients included in the studies may have been at relatively low-risk to begin with, meaning that it would require more time for noticeable effects of interventions to appear. A third possibility was that the quality of care given to controls was sufficiently high to blunt the additional benefits for patients who underwent cardiac rehabilitation, the investigators wrote.
Although the mortality benefit was slow to take effect, it was apparently durable, as seen by pooled data from seven trials with long follow-up, showing that secondary prevention programs reduced the risk of death from all cause by 23% at five years.
In addition, among all patients enrolled in trial that looked at risk of recurrent MI (11,723 patients), the summary risk ratio for a second event at one year was 0.83 (95% CI, 0.74 to 0.94). This benefit did not differ over time in any of the three types of programs.
The authors noted that even the best cardiac rehabilitation program only works when patients who could benefit from it take part.
“Studies have consistently demonstrated that, even in publicly funded health care systems (where access is free), fewer than 50% with coronary artery disease access rehabilitation programs,” they wrote.
They also pointed out that while such programs may save costs by reducing the use of health care resources, the relative costs and cost-effectiveness of the interventions themselves have not been adequately studied.
“Thus, while the implementation of secondary prevention programs on a wide scale for patients with coronary disease is justified,” Clark et al wrote, “it should be accompanied by plans to rigorously evaluate long-term clinical economic outcomes in participants and non-participants.”
Source: Annals of Internal Medicine
Print Version
Tell-a-Friend comments powered by Disqus
