The effect of bariatric surgery on renal function

Abstract Background Obesity is associated with albuminuria and impaired renal function. We previously reported on 38 nondiabetics with improved albuminuria after Roux-en-Y gastric bypass (RYGB). Methods Our objectives were to evaluate changes in renal function, urinary albumin-to-creatinine ratio (UACR), and glomerular filtration rate (GFR) in a larger cohort of patients with normal or mildly impaired renal function, undergoing RYGB or sleeve gastrectomy at 1 year postop. This was a retrospective study. Inclusions: patients with preoperative and 1 year postoperative serum and urine albumin and creatinine and weight (kg). Exclusions: preop chronic kidney disease (CKD)≥Stage 3 or macroalbuminuria (UACR≥300 mg/g). Primary outcomes: changes in UACR and estimated GFR (eGFR) at 1 year. The setting was in a public hospital in New York City, 2004–2011. Results 158 patients met inclusion criteria; 91.8% female; mean age 40.8 years; 84.2% white Hispanic, 14.6 % black. Hypertension was present in 43.0%, diabetes mellitus in 28.5%. UACR was 21.5±3.2 mg/g, decreasing to 10.2±1.2 mg/g at 1 year ( P