According to a new study, donating a kidney does not damage donors' health or reduce their lifespan. Researchers hope their findings encourage more people to come forward to donate a kidney.

Donna Boisen of Coon Rapids, Minnesota didn't think twice when she donated one of her two kidneys to her ailing sister last year. "I do know I had a lot of people say to me, 'Well, gee, I just don't know if I could do that," she said.

Researchers hope a study published this week in The New England Journal of Medicine will allay the fears of many would-be kidney donors.

In the study, the first large-scale examination of lifespan among kidney donors, investigators at the University of Minnesota followed up on 255 people who donated their kidneys between 1963 and 2007.

The study's lead author, Hassan Ibrahim, said he and his team found similar survival rates between donors and non-donors, while the risk of eventually developing kidney failure was one-third lower among the donors.

Dr. Ibrahim says this is likely because the donor screening process results in very healthy people being chosen to donate their organs.

"And I'm hoping people who do have any anxiety regarding kidney donation at least look at these results and discuss kidney donation with the health care professionals who are involved in this process so they can get more accurate information," he said.

Investigators found that 85 percent of donors had excellent function in their remaining kidneys. Only 10 percent had a low amount of protein in their urine -- a sign of some loss of filtering capacity.

Jane Tan of Stanford University screens potential kidney donors. Given the high mortality rate among people with final stage kidney disease, Dr. Tan says she is cautiously optimistic that the results of the study could convince more people to donate kidneys. "We do not know of any long term, bad complications thus far. But when it comes to donor safety, I think it's important to be careful and know what you are doing," she said.


Dr. Tan evaluated the study in this week's issue of The New England Journal of Medicine.