Efficacy of probiotics (Bifidobacterium bifidum G9-1) in patients with type 2 diabetes mellitus and chronic kidney disease complicated by constipation: An exploratory, multicenter, open-label, single-arm study (BIRDIE study).

2026-01-08
Journal of diabetes investigation 17(3)

PubMed: 41504339
DOI: 10.1111/jdi.70236

Study Design

Type: Clinical Trial
Sample size: n = 30
Population: 30 patients with type 2 diabetes mellitus and chronic kidney disease complicated by constipation
Methods: In this multicenter, open-label, single-arm trial, 30 patients with type 2 diabetes mellitus and chronic kidney disease complicated by constipation were administered Bifidobacterium bifidum G9-1 for 12 weeks.

Introduction

Although constipation is a major complication of type 2 diabetes mellitus and chronic kidney disease, evidence for its treatment in these patients remains limited. This study aimed to evaluate the therapeutic efficacy of Bifidobacterium bifidum for constipation in these patients.

Materials and methods

In this multicenter, open-label, single-arm trial, 30 patients with type 2 diabetes mellitus and chronic kidney disease complicated by constipation were administered Bifidobacterium bifidum G9-1 for 12 weeks. The primary endpoint was the proportion of patients with normal stool form (Bristol Scale score ≥3.5 to <4.5). Secondary endpoints included stool form, defecation frequency, and quality of life.

Results

The proportion of patients with normal stool form at week 12 (44.8%; 13 patients) was significantly higher than that at baseline (3.3%; 1 patient; P = 0.002). The median Bristol score significantly increased from baseline by 0.6 at week 6 (P < 0.001) and 0.5 at week 12 (P < 0.001). Defecation frequency significantly increased by 0.2 ± 0.4 from baseline to week 6 (P = 0.026). The total constipation, abdominal pain, and indigestion scores on the Gastrointestinal Symptom Rating Scale significantly decreased. Abdominal symptoms, including straining, feelings of incomplete evacuation, bloating, and discomfort, significantly decreased. Glycated hemoglobin and the estimated glomerular filtration rate did not change significantly, whereas urinary albumin levels significantly decreased at week 6.

Discussion

Bifidobacterium bifidum improved stool form, defecation frequency, and quality of life of patients with type 2 diabetes mellitus and chronic kidney disease complicated by constipation, without worsening glycemic control and renal function.

Research Insights

Supplement	Dose	Health Outcome	Effect Type	Effect Size	Source
Bifidobacterium bifidum G9-1	—	Improved Constipation Symptoms	Beneficial	Moderate	View source The total constipation, abdominal pain, and indigestion scores on the Gastrointestinal Symptom Rating Scale significantly decreased. Abdominal symptoms, including straining, feelings of incomplete evacuation, bloating, and discomfort, significantly decreased.
Bifidobacterium bifidum G9-1	—	Improved Stool Formation	Beneficial	Moderate	View source The proportion of patients with normal stool form at week 12 (44.8%; 13 patients) was significantly higher than that at baseline (3.3%; 1 patient; P = 0.002). The median Bristol score significantly increased from baseline by 0.6 at week 6 (P < 0.001) and 0.5 at week 12 (P < 0.001).
Bifidobacterium bifidum G9-1	—	Increased Defecation Frequency	Beneficial	Small	View source Defecation frequency significantly increased by 0.2 ± 0.4 from baseline to week 6 (P = 0.026).
Bifidobacterium bifidum G9-1	—	Reduced Urinary Albumin	Beneficial	Small	View source urinary albumin levels significantly decreased at week 6.
Bifidobacterium bifidum G9-1	—	Stable Kidney Function	Neutral	Small	View source Glycated hemoglobin and the estimated glomerular filtration rate did not change significantly, whereas urinary albumin levels significantly decreased at week 6.
Bifidobacterium bifidum G9-1	—	Unchanged Glycemic Control	Neutral	Small	View source Glycated hemoglobin and the estimated glomerular filtration rate did not change significantly