Bifidobacteriuradm bifidum G9-1 Intake Improves Gastrointestinal Symptoms in Type 2 Diabetes Mellitus: An Open-Label, Randomized Controlled Trial (Binary STAR Study).

Abstract

To evaluate the effects of probiotics Bifidobacterium bifidum G9-1 (BBG9-1) on gastrointestinal symptoms in patients with Type 2 diabetes mellitus (T2DM) with diarrhoea or constipation. In a 12-week open-label randomised controlled trial, 100 participants were randomized 1:1 to a control or BBG9-1 group, with 12 mg of Bifidobacterium administered daily. The primary endpoint was the change in total Gastrointestinal Symptom Rating Scale (GSRS) score (range: 1-7) in the full analysis set (BBG9-1: n = 43; control: n = 51). BBG9-1 intake significantly improved the GSRS total score (from 2.22 ± 0.67 to 1.83 ± 0.62) compared with control (from 2.08 ± 0.67 to 2.06 ± 0.63; between-group difference, -0.34 [95% CI: -0.55 to -0.14; p = 0.001]). Subgroup analyses indicated greater GSRS total score improvement in women, participants with constipation, aged ≥ 65 years, and BMI < 25 kg/m². Among the GSRS subscales, BBG9-1 showed a significantly greater mean reduction in constipation scores than control (-0.79 ± 1.38 vs. -0.13 ± 1.04; p = 0.013). Although the mean change in diarrhoea scores did not differ significantly (-0.42 ± 1.14 vs. -0.06 ± 1.08; p = 0.14), the follow-up diarrhoea score was significantly lower with BBG9-1 (2.04 ± 1.00 vs. 2.58 ± 1.44; p = 0.049). Through gut microbiota analysis, the relative abundance of genera Phocaeicola increased significantly in the BBG9-1 group (from 15.98 ± 13.75 to 19.56% ± 14.79% vs. from 18.14 ± 14.17 to 18.21 ± 13.58, p = 0.042). Assessment of faecal short-chain fatty acids (SCFAs) revealed no significant changes associated with BBG9-1 administration. The incidence of adverse effects were similar between the groups. BBG9-1 administration significantly improved gastrointestinal symptoms in patients with T2DM. Japan Registry of Clinical Trials (jRCTs051220127).