Bile Acids Show Surprising Spike in Early Diabetic Kidney Disease, Study Finds

A study reported by Bioengineer.org describes new work from Tongji University School of Medicine in Shanghai suggesting that serum total bile acids may rise sharply during the earliest stage of diabetic kidney disease, then decline as the condition advances. The research, published in BMC Endocrine Disorders, focused on whether bile acids could provide an additional signal of early kidney damage in people with type 2 diabetes. That matters because diabetic kidney disease is a major cause of end-stage renal disease worldwide and can progress silently before patients develop symptoms.

The retrospective cross-sectional study examined clinical data from 485 people treated at Shanghai East Hospital between August 2025 and February 2026. Participants were divided into five groups: 87 people with normal glycemia, 126 with uncomplicated type 2 diabetes, and three diabetic kidney disease groups at stages 1, 2 and 3, with 118, 80 and 74 patients respectively. The researchers, Lei Xu, Bo Feng and Xinfeng Yan, used standard kidney markers including urinary albumin-to-creatinine ratio and estimated glomerular filtration rate, then compared serum total bile acid concentrations across disease stages.

The results showed an inverted U-shaped pattern. Median total bile acids were 2.25 micromoles per liter in uncomplicated diabetes, rose to 3.65 micromoles per liter in stage 1 diabetic kidney disease, and fell to 1.95 micromoles per liter by stage 3. After adjusting for factors such as age, diabetes duration, blood pressure, HbA1c, BMI, lipids, eGFR, fatty liver status and medication use, total bile acids remained independently associated with early-stage diabetic kidney disease. The article notes that an exploratory threshold of 2.80 micromoles per liter had modest discriminatory ability, but the authors emphasized that it is not ready for clinical diagnosis without validation in independent cohorts.