Obesity Need Not Rule Out Renal Transplants
FORT LAUDERDALE, Fla.—Elevated BMI in renal transplant recipients does not appear to impact early graft function and the risk of acute rejection, according to study findings presented here at the American Society of Transplant Surgeons 10th Annual State of the Art Winter Symposium.
Investigators led by John A. Daller, MD, PhD, Director of the Abdominal Organ Transplant Program at Temple University Hospital in Philadelphia, reviewed data from consecutive renal transplant recipients between November 2001 and December 2005.
The cohort was 68% African American and most received kidneys from deceased donors. The researchers divided patients into three groups based on BMI (kg/m2): BMI less than 25 (34 patients, mean age 52 years); BMI 25-30 (34 patients, mean age 59 years); and BMI greater than 30 (20 patients, mean age 50 years). All subjects received induction therapy with basiliximab and maintenance triple drug therapy consisting of tacrolimus, mycophenoate, and corticosteroid therapy.
Investigators found no differences among the groups with respect to early graft function and acute rejection rates, but researchers observed a trend toward delayed graft function (DGF) in obese patients. The rates of acute rejection were 6%, 6%, and 5% in those with a BMI less than 25, 25-30, and greater than 30, respectively. The incidence of DGF was 9%, 21%, and 10%, respectively. The findings suggest that the negative impact of BMI may be more related to the metabolic syndrome than direct transplant-related morbidity and mortality, according to investigators.
“Some transplant programs don't want to transplant people with a BMI above a certain number, such as 33, 35 or 38,” said co-investigator Nicole Sifontis, PharmD, Clinical Associate Professor at the Temple University School of Pharmacy in Philadelphia. “The feeling was that if you had an elevated BMI you had increased morbidity and mortality so that people shied away from doing it. Maybe we need to be more aggressive and get them transplanted and then treat their obesity.”
Although study findings are limited by sample size, they suggest that aggressive weight management in end-stage renal disease and transplant recipients may lead to improved outcomes.
“Studies show that obese patients have higher post-transplant mortality than non-obese patients, although they do better than obese patients remaining on dialysis,” Dr. Daller told Renal & Urology News. “We think it is important that obesity is treated aggressively post-transplant. Metabolic syndrome has to be managed. It is just like in a non-transplant patient. The survival will be affected by BMI and the management of obesity.”
Although Dr. Daller's group observed no correlation between BMI and acute rejection, three-year graft survival was inferior in the overweight and obese patients compared with normal weight recipients. Graft survival rates at three years were 91%, 82%, and 85% in subjects with a BMI less than 25, 25-30, and greater than 30, respectively. The rate of opportunistic infections was similar among the groups.