A major study of kidney donations provided the strongest evidence yet that organ donors live just as long as people who go through life with two kidneys, The Wall Street Journal reported Tuesday.
Medical specialists said they plan to tout the findings in transplant literature to encourage more people to become living donors.
Of the roughly 13,600 kidney transplants performed in the U.S. last year, 6,387 were from living donors, with the balance coming from deceased donors.
A living kidney donation extends a recipient's life span by 17 years on average, compared with nine to 11 years when a kidney from a deceased donor is used.
More than 84,000 U.S. patients are currently waiting for a kidney transplant.
The study, published this month in the Journal of the American Medical Association, "reconfirms what many of us have suspected, that living donation is a safe process for donors," said Matthew Cooper, director of kidney transplantation at the University of Maryland Medical Center, who was not involved in the study.
The study also seems to affirm the resilience of a healthy kidney, whose functions include filtering metabolic waste and regulating blood pressure.
When people have two, normally functioning kidneys, neither works at full capacity, past research showed.
After one of the organs is removed, the remaining kidney picks up the slack, growing 20 percent to 25 percent larger and becoming 20 percent to 30 percent more efficient over the next six months.
"That seems to be more than sufficient in the vast majority of donors," said Bryan Becker, president of the National Kidney Foundation and a nephrologist at the University of Wisconsin.
The research, conducted at America's Johns Hopkins University, looked at all 80,347 living kidney donations in the U.S. between 1994 and 2009.
Among the latest findings, in the 90 days after surgery, 3.1 of every 10,000 donors died, a mortality rate about eight times higher than non-donors experienced, but still quite low compared to similar procedures.
Over the longer term, however, donors died no more often than the control group, based on death data obtained from the Social Security Administration.