Renal outcomes of bariatric surgery in obese adults with diabetic kidney disease

Obesity is a pandemic with several significant adverse health outcomes. Chronic kidney disease has been an overlooked consequence of obesity. Among diabetics, obesity is known to amplify the risk for kidney disease. Although bariatric surgery promises significant and sustained weight reduction with favorable impact on metabolic parameters such as glycemic control, hypertension and dyslipidemia, its impact on the renal complications of diabetes is poorly understood. This paper aims to comprehensively evaluate the evidence in the published literature on the impact of bariatric surgery on renal outcomes in obese adults with diabetic kidney disease. While many observational studies have demonstrated significant reduction in proteinuria after bariatric surgery, there is paucity of data regarding changes in renal filtration function such as doubling of serum creatinine or progression to end stage kidney disease. No randomized controlled trials comparing medical vs. surgical therapy in obese adults with diabetic kidney disease exist, hence assessing the metabolic benefits vs. the surgical risks is important before recommending bariatric surgery to this growing patient population. Future studies require a collaborative effort between bariatric surgeons and nephrologists to measure long-term effects of bariatric surgery on renal outcomes incorporating evolving markers of kidney injury to advance this field.