A patient-centered multidisciplinary cardiac rehabilitation program improves glycemic control and functional outcome in coronary artery disease after percutaneous and surgical revascularization

Abstract

Background: Cardiac rehabilitation (CR) is strongly associated with all-cause mortality reduction in patients with coronary artery disease (CAD). The impact of CR on pathological risk factors, such as impaired glucose tolerance (IGT) and functional recovery remains under debate. The aim of the present study is to determine whether CR had a positive effect beside physical exercise improvement on pathological risk factors in IGT and diabetic patients with CAD.

Methods: One hundred and seventy-one consecutive patients participating in a 3-month CR from January 2014 to June 2015 were enrolled. The primary endpoint was defined as an improvement of peak workload and VO2-peak; glycated hemoglobin (HbA1c) reduction was considered as secondary endpoint.

Results: Euglycemic patients presented a significant improvement in peak workload compared to diabetic patients (from 5.75 ± 1.45 to 6.65 ± 1.84 METs vs. 4.8 ± 0.8 to 4.9 ± 1.4 METs , p = 0.018). VO2-peak improved in euglycemic patients (VO2-peak from 19.3 ± 5.3 to 22.5 ± 5.9 mL/min/kg, p = 0.003), while diabetic patients presented only a statistically significant trend (VO2-peak from 16.9 ± 4.4 to 18.0 ± 3.8 mL/min/kg, p < 0.056). Diabetic patients have benefited more in terms of blood glucose control compared to IGT patients (HbA1c from 7.7 ± 1.0 to 7.4 ± 1.1 compared to 5.6 ± 0.4 to 5.9 ± 0.5, p = 0.02, respectively).

Conclusions: A multidisciplinary CR program improves physical functional capacity in CAD setting, particularly in euglycemic patients. IGT patients as well as diabetic patients may benefit from a CR program, but long-term outcome needs to be clarified in larger studies.

Keywords: cardiac rehabilitation; cardiopulmonary test; coronary artery disease; diabetes mellitus; reduced glucose tolerance.

Figure 1

Peak workload and VO2-peak improvement; A. Peak workload comparison between euglycemic (blue bars), impaired glucose tolerance (IGT; yellow bars) and diabetic patients (red bars); B. VO2-peak comparison between euglycemic (blue bars), IGT (yellow bars) and diabetic patients (red bars); NS — not significant.

Figure 2

Linear regression, showing an inverse correlation between fasting glucose and VO2-peak improvement, suggesting that response to cardiac rehabilitation may be impaired by poor glycemic control.