Sex disparities in health outcomes following cardiac rehabilitation for coronary artery disease: a meta-analysis

Referral to, participation in, and execution of cardiac rehabilitation programs are comparatively lower in females than in males. The current study aimed to explore potential sex disparities in cardiorespiratory capacity and clinical outcomes after cardiac rehabilitation for coronary artery disease. Systematic searches were conducted across the PubMed, Embase, Cochrane Library, and Web of Science databases to identify studies assessing primary outcomes of cardiorespiratory capacity (peak oxygen uptake, peak metabolic equivalents, and its changes), secondary outcomes of cardiovascular endpoints (all-cause mortality, myocardial infarction, rehospitalization) and quality of life following cardiac rehabilitation in both female and male patients with coronary artery disease. A total of 22 predominantly observational studies involving 27 624 patients were analyzed, with 7441 (26.9%) being female and 20 183 (73.1%) being male. After cardiac rehabilitation, females showed lower peak oxygen uptake (mean difference -4.82, 95% confidence intervals -6.30 to -3.34 mL/kg/min, <i>P</i> < 0.00001), peak metabolic equivalents (-1.74, -2.34 to -1.14 units, <i>P</i> < 0.001) and its absolute changes from baseline (-0.40, -0.44 to -0.36 units, <i>P</i> < 0.001), as well as the worse quality of life when compared to males. However, there were no significant sex variations in all-cause mortality, myocardial infarction, and rehospitalization. In conclusion, females exhibited lower cardiorespiratory capacity and quality of life than males following cardiac rehabilitation. Despite these disparities, no sex-based differences existed in cardiovascular outcomes during the follow-up period after cardiac rehabilitation in patients with coronary artery disease. (Registration No. CRD42021269222).