The effects of probiotic supplementation on metabolic status in type 2 diabetic patients with coronary heart disease

Background: This study was conducted to evaluate the effects of probiotic supplementation on metabolic profiles in diabetic patients with coronary heart disease (CHD). Methods: This randomized, double-blind, placebo-controlled trial was performed among 60 diabetic patients with CHD, aged 40-85 years at a cardiology clinic in Kashan, Iran, from October 2017 through January 2018. Patients were randomly divided into two groups to take either probiotic supplements (n = 30) or placebo (n = 30) for 12 weeks. Fasting blood samples were taken at the beginning of the study and after the 12-week intervention to determine related markers. Results: After 12-week intervention, probiotic supplementation significantly decreased fasting plasma glucose (beta - 20.02 mg/dL; 95% CI - 33.86, - 6.17; P = 0.005), insulin (beta - 2.09 mu IU/mL; 95% CI - 3.77, - 0.41; P = 0.01), insulin resistance (beta - 0.50; 95% CI - 0.96, - 0.03; P = 0.03) and total-/HDL-cholesterol ratio (beta - 0.27; 95% CI - 0.52, - 0.03; P = 0.02), and significantly increased insulin sensitivity (beta 0.008; 95% CI 0.001, 0.01; P = 0.02) and HDL-cholesterol levels (beta 2.52 mg/dL; 95% CI 0.04, 5.00; P = 0.04) compared with the placebo. Moreover, probiotic supplementation led to a significant reduction in serum high sensitivity C-reactive protein (beta - 0.88 mg/L; 95% CI - 1.39, - 0.38; P = 0.001), and a significant elevation in total antioxidant capacity (beta 108.44 mmol/L; 95% CI 47.61, 169.27; P = 0.001) and total glutathione levels (beta 45.15 mu mol/L; 95% CI 5.82, 84.47; P = 0.02) compared with the placebo. Probiotic supplementation did not affect other metabolic profiles. Conclusions: Overall, we found that probiotic supplementation for 12 weeks had beneficial effects on glycemic control, HDL-cholesterol, total-/HDL-cholesterol ratio, biomarkers of inflammation and oxidative stress in diabetic patients with CHD. Trial registration Clinical trial registration number http://www.irct.ir: IRCT2017082733941N5