Background: The effect of recipient obesity on kidney allograft survival remains enigmatic. The purpose of this study was to evaluate the effect of donor and recipient body mass index on graft survival.
Methods: Retrospective study of 193 consecutive, adult renal transplants, with at least six months follow-up (mean 24+/-14.1 months). Patients were divided into two groups based upon body mass index (BMI), [weight (kg)/height (m)]: normal (<30.0, n=137) and obese (> or =30.0, n=56). Endpoints were graft loss, defined as either total loss of graft function (return to dialysis) or patient death with a functional graft. Unadjusted and adjusted multivariate analysis techniques, including Kaplan-Meier and Cox proportional hazards regression were used. RESULTS.: Individuals with a BMI > or =30 were not more likely to experience graft loss (O.R. 0.93, 95% C.I. 0.50, 1.72). Rates of acute rejection were not increased in obese recipients. While mortality was not increased in the BMI > 30 group, morbidity, especially surgical, had an increased incidence. The ratio of recipient to donor BMI did not influence graft survival.
Conclusion: Obese recipients (BMI > or =30.0) were not at increased risk for graft failure. Additionally, matching donor and recipient BMI's would not appear to substantially improve transplant outcome. Obese recipients do have increased posttransplant morbidity and risk all the known health consequences associated with obesity. Careful evaluation and clinical management of obese patients allows for successful kidney transplantation with results equivalent to normal BMI patients.