Mid- and long-term renal outcomes after metabolic surgery in a multi-center, multi-ethnic Asian cohort with T2DM

Background. Metabolic surgery is recognized for its effectiveness in weight loss and improving outcomes for individuals with type 2 diabetes mellitus (T2DM). However, its impact on renal function, especially in multi-ethnic Asian populations, remains underexplored. This study investigates mid- and long-term renal outcomes following metabolic surgery in Asian patients with T2DM. Methods. This retrospective cohort study utilized data from the Asian Diabetes Surgery Study (ADSS), involving T2DM patients aged 20–79 who underwent metabolic surgery from 2008 to 2015. The primary outcome was the change in estimated glomerular filtration rate (eGFR) at 1, 3, and 5 years post-surgery, with adjustments for confounders. Secondary outcomes included changes in chronic kidney disease (CKD) stages and the relationship between weight loss and eGFR changes. Data were analyzed using univariate and multivariable regression analyses, along with the McNemar test. Results. The study included 1513 patients with a mean age of 42.7 years. The results revealed that a significant improvement in eGFR was observed at 1-year post-surgery (112.4 ± 32.0 ml/min/1.73 m^2, P < .001), with a shift toward less severe CKD stages. However, this improvement was not sustained at 3 and 5 years. No significant correlation was found between weight loss and eGFR changes at 1-year follow-up. Conclusion. Metabolic surgery significantly improves renal function at 1 year postoperatively in Asian individuals with T2DM, highlighting its potential benefits beyond glycemic control and weight loss. The long-term effects on renal function require further investigation.