Purpose: Obesity is a common risk factor in patients (pts) with coronary artery disease (CAD). Several studies have shown a reduction in functional capacity in this group of pts. Our aim was to evaluate the impact of a cardiac rehabilitation program (CRP) in functional capacity and cardiovascular risk factors in Obese (OB) vs Non Obese (NOB) pts with CAD.
Methods: We performed an analysis from a prospectively collected registry including 1549 consecutive pts that participated in a multidisciplinary CRP (a supervised aerobic exercise training protocol, 2 times/week during 3 months) from 2008 to July 2014. From those, we enrolled 1213 pts with CAD. Pts were divided according to their body max index (BMI), being OB if BMI≥30 and NOB if BMI<30 kg/m2. Several parameters were collected at the beginning and at the end of the CRP: functional capacity (maximal exercise capacity on treadmill stress test estimated in metabolic equivalents (METS)), physical activity (through International Physical Activity Questionnaire), and risk factor control, namely, blood pressure (BP), lipid profile and HbA1c. Statistical analysis was performed using SPSS, with a level of statistical significance p<0.05.
Results: In our study, from a total of 1213 pts included, 17% (n=206) were OB (mean BMI 32,6±2,6 kg/m2). The mean age in both groups was 60±10 years old. In the baseline profile, OB pts had a lesser proportion of men (66% vs 80% p<0.001) and a higher percentage of hypertension, diabetes and dyslipidemia (72.3% vs 58.5% p<0.001; 51.9% vs 26.8% p<0.001; 78.6% vs 68.6% p=0.006). The baseline functional capacity was lower in OB pts (7.8±2.2 vs 8.8±2.4 METS p<0.001). After CRP, both groups showed a statistically significant increase in functional capacity (7.8±2.2 to 9.2±2.1 METS OB vs 8.8±2.4 to 10.4±2.2 METS NOB both p<0.001), with a similar rate of improvement between groups (ΔMETS 1.3±1.2 (17.9%) OB vs 1.4±1.2 (18.1%) NOB p=0.188). In subgroup analysis, with respect to gender, age <65|≥65 years old and diabetic/non diabetic pts, there was no differences in functional capacity progress. They also displayed a significant improvement in physical activity, similar in both groups (ΔIPAQ MET-minutes/week 1501±1725 OB vs 1530±1821 NOB p=0.844). In relation to risk factors control, CRP had a positive impact in all studied variables, without main differences between groups, except for BMI reduction that was higher in OB pts (ΔIMC 1.2±1.3 vs 0.6±0.91 kg/m2 p<0.001).
Conclusion: In our study, obesity is not a limiting factor to the improvement of functional capacity after CRP. Secondary prevention programs cannot ignore the challenge of obesity management in CAD pts and the need for special approaches to weight control.