Reconciling systematic reviews of exercise-based cardiac rehabilitation and secondary prevention programmes for coronary heart disease

摘要

Findings of systematic reviews incorporating meta-analysis are by nature hypothesis generating and should be carefully and judiciously interpreted. This need is epitomized by two of the largest reviews of interventions to support risk factor reduction after a diagnosis of coronary heart disease (Table I). These reviews both included randomized trials published in a similar timeframe (up to 2003 or 2004) that compared the effects of various risk factor reduction programmes for patients with confirmed coronary heart disease to usual care.In 2004, a Cochrane review found that supervised and unsupervised exercise-based cardiac rehabilitation provided to patients with different forms of coronary heart disease lowered all cause total mortality by 20% and cardiac mortality by 26% in 48 trials of 8940 patients. The reviewers concluded that there was 'no difference in mortality effect between exercise-only cardiac rehabilitation and comprehensive cardiac rehabilitation, or by exercise dose or duration of follow-up'. Also, the exercise-based programmes did not reduce recurrent myocardial infarction and the need for repeat coronary revascularization to statistically significant levels.