Bariatric Surgery Improves Renal Function: a Large Inner-City Population Outcome Study.

ABSTRACT

BACKGROUND: Bariatric surgery is associated with improved renal dysfunction in general population studies. The study examined the effects of bariatric surgery on renal function in a predominantly Hispanic and African American population at a community hospital in New York, USA. METHODS: This retrospective study analyzed prospectively collected bariatric surgical data from 2247 patients (89% female) who underwent bariatric surgery at a single center. Changes in glomerular filtration rate (eGFR), urine albumin-creatinine ratio (UACR), micro- and macroalbuminuria, and hyperfiltration, which were measured preoperatively and then yearly for 3 years postoperatively, were evaluated with t tests and logistic regression analysis, after adjusting for confounding variables. The mean age of the patients at surgery was 37.1 years; the mean preoperative body mass index was 45 ± 7 kg/m2. RESULTS: The results obtained 3 years postoperatively showed the following significant improvements compared with the preoperative values mean UACR decreased from 40.3 to 11.1 mg/g, mean eGFR improved from 79.4 to 87.3 mL/min, the prevalence of microalbuminuria decreased from 13.7 to 6.2%, the prevalence of macroalbuminuria decreased from 2.5 to 0%, and the prevalence of hyperfiltration decreased from 4.4 to 2.7% (all P < .0001). In adjusted multivariate regression analysis, these results remained significant after adjusting for age, sex, race, type of surgery, and presence of diabetes mellitus or hypertension. CONCLUSION: In this large study at an inner-city hospital, bariatric surgery was associated with significant improvements in renal dysfunction parameters. These results could assist with informed decisions regarding indications for bariatric surgery.