Large Mayo study reaffirms safety of donating kidneys
Authors reviewed outcomes for over 3,000 procedures spanning two decades. Donation led to serious complications in only 2.5% all cases, and no deaths or subsequent need for missing kidney.
ROCHESTER, Minn. — The largest study of its kind — and with the longest follow-up yet — has reaffirmed that people who donate a kidney face an extremely small risk of complications.
There are currently 90,000 Americans waiting for a kidney, and recipients from living donors have a higher rate of success.
The study, published recently in the journal Mayo Clinic Proceedings, also determined the procedure to be safe for people with risk factors ordinarily thought to be prohibitive for donating an organ.
The authors, a dozen Mayo Clinic transplant specialists, reviewed the medical records for more than 3,000 living kidney donors, over a 20-year period, at a single medical site.
Where previous kidney donor outcome studies had looked only at complications prior to leaving the hospital, the Mayo review looked at complications up to 120 days post discharge.
They found that 12.4% of patients had some complications, but only 2.5% had major complications and no patients died. Fewer than 2% of patients required a second operation, and all but one of those was related to the incision.
Most complications occurred following discharge and were associated with incision type, a history of previous abdominal surgery and non-white race, but those were not predictive of major risk complications.
"We did this because we know that this is a safe procedure, otherwise we wouldn't be doing this work for 20-30 years," said Dr. Timucin Taner, coauthor and transplant surgeon, Mayo Clinic.
"But there's really no large data set that people can actually see. So we did this study to show the rest of the world that this is actually indeed a very safe procedure."
Taner says most of the complications happened during the first five to seven years in the 20-year period between 2000 and 2020 under review, and that "once we learned those lessons," incidence of complications have dropped since 2007.
"We've been doing a lot of living donor transplants over the years, so that gave us a chance to look into more than 3,000 donors," he said.
"There are a certain number of complications that can happen ... several days to a few weeks after the procedure," he said. "Since we followed those closely, we were able to correct whatever the difficulty was, which resulted in the really, really low complication rate overall."
Taner says another finding of interest was the lack of any special risk factors for major complications among persons who are heavier, based on the fact that a third of the donor pool had a Body Mass Index of 30.
"That's another reassurance that we can do these surgeries very safely in a lot of people who would like to donate a kidney."
Kidney donation is a laparoscopic surgery that entails a small incision and one or two days in the hospital.
"Back in the day, 20 years ago, people used to have a big incision on their side which really held them back for several months of recovery," Taner said, "None of those are true anymore."
Barring strenuous exercise, donors are able to stay active and get back to work in three to four weeks without limitations.
"Our study and others looking at the long term impact of living with one kidney show no negative impacts," Taner said. They have a full life span."
Taner said that the procedure entails a thorough health evaluation in order to establish the low likelihood a donor will ever need to replace their remaining kidney.
Though donors get high priority for kidney donation should that ever occur, no person in the 20-year, 3,000-person study ever needed to replace their surviving kidney.