Cardiometabolic responses to cardiac rehabilitation in people with and without diabetes

Type 2 diabetes and cardiometabolic comorbidities manifesting as the metabolic syndrome (MetS) are highly prevalent in coronary heart disease (CHD) patients attending cardiac rehabilitation (CR). The study aimed to determine the prevalence of cardiometabolic derangements and MetS, and compare post-CR clinical responses in a large cohort of CHD patients with and without diabetes.

Analyses were conducted on 3953 CHD patients [age: 61.1 ± 10.5 years; 741 (18.7%) with diabetes] that completed a representative 12-week CR program. A propensity model was used to match patients with diabetes (n = 731) to those without diabetes (n = 731) on baseline and clinical characteristics.

Diabetic patients experienced smaller improvements in metabolic parameters after completing CR, including abdominal obesity, and lipid profiles (all P ≤ .002), compared to non-diabetic patients. For both groups, there were similar improvement rates in peak metabolic equivalents ([METs]; P < .001); however, peak METs remained lower at 12-weeks in patients with diabetes than without diabetes. At baseline, the combined prevalence of insulin resistance (IR) and diabetes was 57.3%, whereas IR was present in 48.2% of non-diabetic patients, of which rates were reduced to 48.2% and 32.8% after CR, respectively. Accordingly, MetS prevalence decreased from 25.5% to 22.3% in diabetic versus 20.0% to 13.4% in non-diabetic patients (all P ≤ .004).

Completing CR appears to provide comprehensive risk reduction in cardio-metabolic parameters associated with diabetes and MetS; however, CHD patients with diabetes may require additional and more aggressive attention towards all MetS criteria over the course of CR in order to prevent future cardiovascular events.