Effect of Gastric Bypass vs Best Medical Treatment on Early-Stage Chronic Kidney Disease in Patients With Type 2 Diabetes and Obesity: A Randomized Clinical Trial

IMPORTANCE: Early-stage chronic kidney disease (CKD) characterized by microalbuminuria is associated with future cardiovascular events, progression toward end-stage renal disease, and early mortality in patients with type 2 diabetes. OBJECTIVE: To compare the albuminuria-lowering effects of Roux-en-Y gastric bypass (RYGB) surgery vs best medical treatment in patients with early-stage CKD, type 2 diabetes, and obesity. DESIGN, SETTING, AND PARTICIPANTS: For this randomized clinical trial, patients with established type 2 diabetes and microalbuminuria were recruited from a single center from April 1, 2013, through March 31, 2016, with a 5-year follow-up, including prespecified intermediate analysis at 24-month follow-up. INTERVENTION: A total of 100 patients with type 2 diabetes, obesity (body mass indexes of 30 to 35 [calculated as weight in kilograms divided by height in meters squared]), and stage G1 to G3 and A2 to A3 CKD (urinary albumin-creatinine ratio [uACR] >30 mg/g and estimated glomerular filtration rate >30 mL/min) were randomized 1:1 to receive best medical treatment (n = 49) or RYGB (n = 51). MAIN OUTCOMES AND MEASURES: The primary outcome was remission of albuminuria (uACR