The association between diabetes and gallstones: a nationwide population-based cohort study

Introduction
Evidence regarding the association between diabetes mellitus (DM) and cholelithiasis is still inconsistent.

Aim
To examine the association between diabetes and gallstones and the commonly associated factors in a nationwide population-based cohort investigation.

Material and methods
The demographic and outcome variable data were extracted from the National Health and Nutrition Examination Survey (NHANES) database for the years 2017–2018.

Results
A total of 5376 individuals were included in the final analysis, with a mean age of 51.3 ±17.8 years. Females constituted 51.5% of the included individuals, and the overall mean body mass index (BMI) was 29.8 ±7.4 kg/m2. The prevalence of diabetes was 16.2% among the included individuals, with a mean age of 50.6 ±13.6 years at diagnosis of diabetes, and only 4.5% were taking insulin. The prevalence of cholelithiasis was 11.2%, with a mean age of 44.4 ±16.1 years at diagnosis, and 11.3% had previous cholecystectomy (gallbladder surgery.) There was a significant increase in gallstone rates among diabetic patients as compared to non-diabetics in the unadjusted (OR = 2.30; 95% CI: 1.89–2.79; p < 0.001) and adjusted (OR = 1.52; 95% CI: 1.20–1.92; p < 0.001) models. Moreover, this association was not time-dependent where the “age when first told you had diabetes” did not show a significant influence on the gallstone rate, whether in unadjusted (OR = 1.01; 95% CI: 1.00–1.02; p = 0.221) or adjusted (OR = 1.01; 95% CI: 0.99–1.03; p = 0.395) models. Furthermore, insulin usage was found to be a significant predictor of cholelithiasis, whether in unadjusted (OR = 2.39; 95% CI: 1.74–3.28; p < 0.001) or adjusted (OR = 1.52; 95% CI: 1.05–2.19; p = 0.026) models.

Conclusions
DM and insulin therapy are possible risk factors for developing cholelithiasis.