Effect of a phase 2 cardiac rehabilitation program on obese and non-obese patients with stable coronary artery disease

Abstract

Background: Obesity is associated with significant cardiovascular morbidity and mortality effects. Cardiac rehabilitation programs cause a significant reduction in cardiovascular mortality and a reduction in all cardiovascular risk factors. Up to 80% of patients referred to cardiac rehabilitation programs are either overweight or obese. This study aimed to compare the effects of a phase 2 cardiac rehabilitation program on obese and non-obese patients with stable coronary artery disease following total revascularization by coronary angioplasty. Results: This was a prospective study including 120 patients with stable coronary artery disease. Patients were enrolled in a 12-week phase 2 cardiac rehabilitation program. Patients were classified into two groups based on their body mass index (BMI): those with a BMI < 30 kg/m2 were considered non-obese (n = 58) while those with a BMI ≥ 30 kg/m2 were considered obese (n = 62). At baseline, BMI and blood pressure (BP) were recorded; fasting blood sugar, triglyceride levels, total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were assessed; and echocardiography was used to measure left ventricular ejection fraction (LVEF). These were re-assessed after completion of the program. At baseline, there were more females in the obese group 20 (32.25%) vs 6 (10.13%) (p = 0.04), more hypertensives (p = 0.023), and less smokers 32 (51%) vs 46 (79%) (p = 0.025). Obese patients achieved fewer metabolic equivalent of tasks (METs) 7.97 ± 2.4 vs 9.74 ± 2.47 (p = 0.007) and had higher LDL-C levels 121.63 ± 36.52 mg/dl vs 95.73 ± 31.51 mg/dl (p = 0.005). At the end of the program, obese patients showed more reduction in BMI − 1.78 ± 1.46 kg/m2 vs − 0. 60 ± 0.70 kg/m2 (p < 0.001) and systolic and diastolic BP (p = 0.016 and 0.038, respectively). LDL-C level was more reduced in the obese group − 25.76 ± 14.19 mg/dl vs − 17.37 ± 13.28 mg/dl (p = 0.022). Non-obese patients had more increase in LVEF (p = 0.024). There was no difference between obese and non-obese patients in the magnitude of increase in METs achieved (p = 0.21). Conclusion: Cardiac rehabilitation programs lead to an improvement in cardiovascular disease risk factors with more reduction in BMI, BP, and LDL-C levels in obese patients compared to non-obese ones. LVEF was more increased in non-obese individuals. Exercise capacity in the form of METs achieved was equally improved in both groups.