The effect of body mass index on long-term renal allograft survival

Background A number of factors have been implicated in decreasing long-term renal graft survival. Factors such as living versus cadaveric donor status , acute rejection, and HLA matching have been studied in detail. Mild obesi ty defined as a body mass index (BMI) of >25 has been found to have a delet erious effect on a number of physiologic processes. We studied the effect o f a BMI >25 on long-term renal transplantation outcome. Methods. A total of 405 patients who underwent transplantation at Saint Bar nabas Medical Center from 1990 to 1997 were evaluated. All known variables impacting on long-term graft function were collected. Multivariate analysis utilizing the Cox-proportional hazard model and Kaplan-Meier actuarial sur vival were applied to these risk factors. Results. BMI >25 was isolated as an independent risk factor for both decrea sed graft survival and patient survival (relative risk 2.0 for each). Cadav eric donor status, acute rejection, and use of azathioprine versus mycophen olate mofetil were the only other significant risk factors. Conclusions. Mild obesity before transplantation has a negative impact on l ong-term renal graft and patient survival.