The promising effects of a multi-species synbiotic preparation on metabolic profile in elderly patients with type 2 diabetes and high cardiovascular risk: a randomized, triple-blind, placebo-controlled trial

BACKGROUND: Elderly patients with type 2 diabetes (T2DM) experience a significantly raised risk of cardiovascular disease. We aimed to determine the effect of the multi-species synbiotic supplementation in elderly patients with T2DM and high cardiovascular risk. METHODS: Ninety-six patients with T2DM, aged ≥65 years with high cardiovascular risk, were enrolled between January 2022 and May 2023 and randomly allocated to receive a synbiotic supplement, containing a multi-species probiotic, and fructooligosaccharide as a prebiotic, or placebo supplements for 4 months. The primary outcome was the mean difference in weight change between synbiotics and placebo. The secondary outcomes were the mean difference in modifications in the body fat mass (BFM), lean body mass (LBM), and biochemical parameters, including glucose metabolism indices, lipid profile, and adhesion molecules between the two groups due to the intervention. RESULTS: (-0.36 to -0.51)], and BFM [-0.99 kg (-1.05 to -0.93)] decreased significantly in the synbiotic group compared to the placebo group in the linear mixed analysis of covariance analysis (all p < 0.001). The mean serum Low-density-Lipoprotein (LDL-C) [-10.83 mg/dl (-14.78 to -6.88)], and total cholesterol [-11.78 mg/dl (-16.44 to -7.11)], vascular cell adhesion molecule 1 (VCAM-1) [-85.70 ng/L (-150.14 to -21.26)], fasting plasma glucose (FPG) [-22.83 mg/dl (-31.30 to -14.36)], and homeostatic model assessment for insulin resistance (HOMA-IR.) [-1.31 (-1.75 to -0.86)] improved in the synbiotic group significantly compared to the placebo group (p = 0.002, p = 0.012, p = 0.017, p < 0.001, p = 0.003 and p = 0.001, respectively). No serious adverse events were detected. CONCLUSION: A multi-species synbiotic preparation benefits elderly patients with T2DM and high cardiovascular risk and improves weight, BMI, BFM, and plasma levels of total cholesterol, LDL-C, VCAM-1, FPG, and HOMA-IR. These findings suggest synbiotics may have health-promoting impacts in older patients with diabetes.