For patients on the waiting list for a kidney transplant, severe and morbid obesity are associated with a lower chance of receiving an organ, reports a study in the February Journal of the American Society of Nephrology.
Led by Dr. Dorry L. Segev of the Johns Hopkins University School of Medicine, the researchers used data from the United Network for Organ Sharing (UNOS) to examine how obesity affects waiting times for kidney transplantation. "The results identify a potential bias in organ allocation that is not consistent with the goals of our allocation system," Dr. Segev comments. "Obese patients are waiting longer for kidney transplants when compared with their non-obese counterparts, even after adjusting for all medical factors tracked through UNOS."
Dr. Segev and colleagues analyzed data on more than 132,000 patients wait-listed for kidney transplants from 1995 to 2004. As obesity increased, the likelihood of receiving a transplant decreased.
Adjusted for other factors, the chances of receiving a kidney transplant were 27 percent lower for patients classified as severely obese and 44 percent lower for morbidly obese patients, compared to normal-weight patients. (The chances of receiving a transplant were not significantly reduced for patients classified as overweight or mildly obese.)
In addition, when a kidney became available, patients in the highest categories of obesity were more likely to be "bypassed"—that is, their physician was more likely to decline the offer of a kidney. The chances of being bypassed were 11 percent higher for severely obese patients and 22 percent higher for morbidly obese patients.