Multimorbidity Attenuates Improvement In Peak Oxygen Uptake In Obese Patients Undergoing Cardiac Rehabilitation

PURPOSE: Cardiac rehabilitation (CR) patients have higher prevalence of multimorbidity compared to the general population. Cardiorespiratory fitness (CRF) is closely linked to rehospitalizations and mortality. CR improves CRF, whereas multimorbidity and obesity independently attenuate CRF. This study examined the impact of multimorbidity on CRF among obese CR patients. METHODS: We included 271 patients (≥ 18 yrs) with BMI ≥ 30 kg/m2 who underwent cardiopulmonary exercise testing pre and post CR at Mayo Clinic from 1999-2017. The prevalence of 21 chronic conditions (CCs) defined by the US Department of Health and Human Services was assessed using the Rochester Epidemiology Project records-linkage system. The CCs were grouped as: cardiometabolic only (CMC), CMC + Somatic, CMC + Mental health, and CMC + Somatic and Mental health. Percent change in peak oxygen consumption (VO2 peak) pre-post CR was analyzed by Kruskal-Wallis test. RESULTS: Patients were 62.3 ± 10.1 yrs old with BMI of 34.6 ± 4.3 kg/m2 and 75.6% were male. Median CR sessions attended was 33 (24, 35). Percent change in peak VO2 was 10.3% ± 16.0% and median number of CCs was 7 (5, 8). Patients with <7 CC had greater improvement in peak VO2 compared to those with ≥7 CC (12.6% vs 8.3%, respectively, p < 0.05). Percent change in peak VO2 was lower in Somatic + Mental health, and Somatic only groups (8.9% in both groups) compared to Mental health and CMC only groups (15.9% and 16.5%, respectively), p < 0.05. The number of CCs was higher in Somatic + Mental health and somatic only groups, p < 0.01. CONCLUSIONS: Our results suggest multimorbidity attenuates improvement of CRF among obese patients undergoing CR. The presence of somatic conditions in addition to CMC impacts CRF more negatively compared to CMC alone or combined with mental health conditions. Individualized treatment plans targeting the adverse effects of multimorbidity on CRF in obese patients are necessary.