Relationship Between Number of Cardiac Rehabilitation Exercise Training Sessions, Muscle Mass, and Cardiorespiratory Fitness in Rural Elderly Patients with Coronary Artery Disease

PURPOSE: This study aimed to compare the effects of a cardiac rehabilitation (CR) exercise program on skeletal muscle index (SMI) and cardiorespiratory fitness (CRF) in patients aged ≥65 years. PATIENTS AND METHODS: From January 2012 to December 2021, patients living in rural regions aged ≥65 who underwent percutaneous coronary intervention for acute myocardial infarction (AMI) and at least one CR exercise session were enrolled. We retrospectively reviewed the medical records of the patients who underwent an exercise tolerance test (ETT) at initial and 3-month follow-ups. A total of 36 patients were enrolled who underwent a mean of 6.56 exercise sessions and were divided into groups based on the number of center-based CR (CBCR) sessions: 14 in Group A (≥7 sessions) and 22 in Group B (<7 sessions). In CBCR session, we comprehensively counseled them about their nutrition, smoking cessation et al. Both groups underwent an ETT after 12 weeks. The outcomes were CRF parameters examined by a cardiorespiratory exercise test and the SMI examined by bioimpedance analysis (BIA). RESULTS: The number of exercise sessions was significantly correlated with the rate of SMI change. Group A showed significant increases in metabolic equivalent of task (MET), maximal oxygen uptake (VO2max), and SMI after 3 months. There were significant differences in the rates of change in MET, VO2max, and SMI between the two groups. CONCLUSION: CRF significantly improved in Group A in a short period. Further studies are required to increase long-term CBCR adherence in elderly patients with AMI in rural regions.