Metabolic profile and exercise capacity outcomes: their relationship to overweight and obesity in a Canadian cardiac rehabilitation setting

Abstract

Purpose: Obesity remains a significant health problem for cardiac rehabilitation patients. The purpose of this study was to examine the relation of overweight and obesity to cardiovascular risk factors in patients, and to compare the change in cardiovascular risk factor profiles in patients with coronary artery disease undergoing cardiac rehabilitation at a tertiary care hospital center in Ontario, Canada.

Methods: Retrospective analysis of cross-sectional data for 3542 patients, ages 63 +/- 11 years, stratified by body mass index (BMI), was performed.

Results: The findings showed that 81% of the patients had a BMI exceeding 25 kg/m(2), and that 35% of the patients were obese (BMI > or =30 kg/m(2)). After adjustment for age, sex, smoking, hypertension, diabetes, and peak power output, BMI was a significant independent predictor of a higher total cholesterol level, higher fasting blood glucose and triglyceride levels, and lower levels of high-density lipoprotein cholesterol. The Adult Treatment Panel III criteria were used to examine the prevalence of the metabolic syndrome for each BMI group. At baseline, 77% of the obese males in classes 2 and 3 had three or more risk factors for the metabolic syndrome, as compared with 68% of the obese females in classes 2 and 3. After 24 weeks of intervention, the outcome data for 1353 patients showed that despite no change in body weight, all the BMI groups demonstrated significant improvements in metabolic profiles and peak exercise capacity.

Conclusions: Cardiac rehabilitation results in significant improvement in the cardiovascular risk profile at all levels of BMI, independently of weight loss. Future studies should examine whether targeting weight loss in cardiac rehabilitation further improves outcomes and the overall cardiovascular risk profile.