Effects of comprehensive cardiac rehabilitation on functional capacity in a middle-income country: a randomised controlled trial

Objective: Despite the growing epidemic of cardiovascular diseases in middle-income countries, there is insufficient evidence about cardiac rehabilitation (CR) in these countries. Thus, the effects of comprehensive CR on functional capacity and risk factors were investigated in Brazil, to test the hypothesis that it results in better outcomes than exercise-only or no CR.

Methods: Single-blinded, randomised controlled trial with three parallel arms: comprehensive CR (exercise+education) versus exercise-only CR versus wait-list control. Eligible coronary patients were randomised in blocks of four with 1:1:1 concealed allocation. Participants randomised to exercise-only CR received 36 exercise classes; comprehensive CR group also received 24 educational sessions. The primary outcome was incremental shuttle walk test (ISWT) distance; secondary outcomes were cardiovascular risk factors. All outcomes were assessed at baseline and 6 months later. Analysis of covariance was performed on the basis of intention-to-treat (ITT) and per-protocol.

Results: 115 (88.5%) patients were randomised; 93 (80.9%) were retained. There were improvements in ISWT distance from pretest to post-test with comprehensive (from 358.4±132.6 to 464.8±121.6 m; mean change=106.4; p<0.001) and exercise-only (from 391.5±118.8 to 488.1±106.3 m; mean change=96.5, p<0.001) CR, with significantly greater functional capacity with comprehensive CR versus control (ITT: mean difference=75.6±30.7 m, 95% CI 1.4 to 150.2). There were also reductions in systolic blood pressure with comprehensive CR (ITT: reduction of 6.2±17.8 mm Hg, p=0.04). There were no significant differences for other outcomes.

Conclusion: Results showed clinically significant improvements in functional capacity and blood pressure with CR, and significantly greater functional capacity with comprehensive CR compared with usual care.