Potential kidney donors can stop worrying about the long-term effects such a donation might have on their health and longevity.
The first long-term study of kidney donors has found that people who give kidneys to others not only have a normal life span, they also have fewer kidney problems than the general population -- perhaps because they are healthier to begin with. "We've suspected all along that kidney donation is a safe practice, but there has never been a long-term study with large numbers of patients in the United States," said Dr. Hassan N. Ibrahim of the University of Minnesota Medical School, who led the study.
The report published today in the New England Journal of Medicine analyzed the outcome for nearly 3,700 donors who were studied for as long as 40 years.
"We're hoping that these results will make the decision to donate easier for people and alleviate anxiety about living with one kidney," he added.
Kidneys are the most commonly transplanted organ in the United States, with 8,816 transplants performed last year with organs from deceased donors and 4,927 from living donors, according to the United Network for Organ Sharing, or UNOS.
But the need is growing dramatically because of sharp increases in diabetes and high blood pressure, the most common causes of kidney failure.
The National Kidney Foundation estimates that there are 350,000 Americans suffering from end-stage kidney disease, with about 67,000 dying each year without even making it onto the waiting list for transplants. That list currently sits at 78,210, according to UNOS, and the wait for a donor is about five to seven years -- longer than most of the victims survive.
The alternative to transplants is kidney dialysis, but it is a poor substitute because it does not fulfill many of the secondary functions of the kidney, such as the production of hormones. As a consequence, about 20% of dialysis patients die each year.
Earlier studies had suggested that living donors might be the answer. Small studies of World War II war injuries showed that soldiers who lost a kidney in battle were able to function effectively with their remaining kidney, and in the 1960s surgeons began experimenting with living-donor transplants. Such transplants grew increasingly popular, with the number peaking at 6,647 in 2004.
Joel Newman, a UNOS spokesman, noted that there were a couple of highly publicized deaths of living donors early this decade during surgery, leading hospitals to be more selective in whom they would allow to donate.
