Effects of probiotic supplementation on major cardiovascular-related parameters in patients with type-2 diabetes mellitus: a secondary-data analysis of a randomized double-blind controlled trial

Background Patients with type-2 diabetes mellitus (T2DM), have a higher risk of future cardiovascular diseases (CVD). Meanwhile, probiotics are shown to positively impact CVD-related parameters. This randomized controlled trial sought to evaluate the effects of probiotic supplementation on fundamental CVD-related parameters including atherogenic index of plasma (AIPs), blood pressure, the Framingham risk score, and antioxidant markers in patients with T2DM. Methods Eligible participants were randomly assigned to receive 2 capsules/day of probiotics [each containing 500 mg of L.acidophilus(5 x 10(10) CFU/g), L.plantarum(1.5 x 10(10) CFU/g), L.fermentum(7 x 10(9) CFU/g), L.Gasseri(2 x 10(10) CFU/g) and 38.5 mg of fructo-oligo-saccharides], or placebo for 6 weeks. Systolic and diastolic blood pressures (SBP and DBP, respectively), mean arterial blood pressure (MAP), atherogenic indices (the ratios of TC/HDL-C, LDL-C/HDL-C, and logTG/HDL-C), the 10-year Framingham CVD risk score, as well as total anti-oxidant capacity (TAC), paraoxonase (PON) and total oxidant status (TOS) were evaluated before and after the study. Final analyses were adjusted based on baseline parameters, and potential covariates including age, sex, PUFA and sodium intakes. Results Sixty participants completed the study. Compared with placebo, probiotic supplementation resulted in a significant decrease in SBP[-9.24 mmHg(- 14.5, - 3.9)], DBP[- 3.71 mmHg(- 6.59, - 0.83)], MAP[- 5.55 mmHg(- 8.8, - 2.31)], the Framingham risk categories [medium-low(1.5) vs. 2 (medium)] and logTG/HDL-C ratio [- 0.08 (- 0.14, 0)] (All P < 0.05) at the end of the study. No significant changes were observed in the antioxidant markers. Conclusion Overall, probiotic supplementation for 6 weeks led to a significant improvement in major CVD-related parameters in populations with T2DM, suggesting the possible beneficial role of probiotics in lowering the risk of future CVDs associated with diabetes. Nevertheless, more studies are needed to confirm the veracity of these results. Trial registration: IRCT2013100714925N1 (registered on November, 9th, 2013).