Obesity in Kidney Transplant Recipients and Candidates

The prevalence of obesity in dialysis patients is increasing, and as a result, more obese dialysis patients are being evaluated for kidney transplant. Despite several limitations associated with the use of body mass index (BMI), BMI is commonly used to define obesity, with many transplant centers using BMI of 30-35 kg/m² as a limit for transplant eligibility. This limit evolved from the belief that obese patients have more complications and shorter transplant and patient survival than ideal-weight patients. Data for obesity and posttransplant complications are conflicting, with the exception of increased risk of postoperative wound complications, and there are no large trials showing a benefit of weight loss before transplant on subsequent patient or transplant survival. In our opinion, patient death and transplant failure rates in patients with BMI of 30-35 kg/m² are low enough that these individuals should not be excluded from transplant. Weight gain posttransplant is relatively common, and although sustained weight loss through conservative intervention is difficult to achieve, prevention of weight gain is a more feasible goal that should be addressed routinely. Although obesity is a complex and often multifactorial clinical condition that includes nonmodifiable factors, obese individuals often are viewed as being solely responsible for their obesity. Accordingly, in addition to encouragement of lifestyle modification, available pharmacologic and surgical options should be reviewed in appropriate patients. After pharmacologic and/or surgical interventions, close monitoring of immunosuppressive medications is necessary because of variability in drug absorption.

Index Words: Obesity, kidney transplant, graft function, posttransplant diabetes, gastric bypass