Want To Donate A Kidney? Stop Smoking To Improve Transplant Odds, Study Suggests

THURSDAY, Oct. 15, 2026 (HealthDay News) — Kidneys donated by smokers are less likely to survive transplant, a new study says.

Donated kidneys are 13% more likely to fail if they come from a person with any history of smoking, and the odds are even worse for organs donated by heavy smokers, researchers reported recently in the journal Kidney360.

“Our findings suggest that smoking history, particularly heavy smoking exposure, should be considered during living donor evaluation and counseling,” lead researcher Dr. Machi Kaneko McBee, a pediatric nephrologist with the University of California-Davis, said in a news release.

Smoking is a known risk factor for kidney disease, but it’s not known whether it might impact the outcome of a kidney donation, researchers said in background notes.

For the study, researchers analyzed data for nearly 88,500 people who received a kidney transplant from a living donor. The transplants occurred in the United States between 2004 and 2022 and were tracked by the Organ Procurement and Transplantation Network.

Results showed that any history of smoking came with a 13% increased risk of graft loss and an 18% increased risk of rejection within the first year of transplant.

If the kidney came from a heavy smoker, the odds of a successful transplant were even more dire.

Among donors with a smoking history of more than 20 pack-years — the equivalent of smoking one pack of cigarettes a day for over 20 years — researchers found that kidney transplants had a:

• 29% higher risk of graft loss

• 24% higher risk of a delay in kidney function

• 32% higher risk of organ rejection

Kidneys from former smokers did perform better than those from active smokers, suggesting that if donors quit this might help reduce transplant risk, researchers said.

“Recipients with grafts from actively smoking living donors had a 10% higher hazard of graft loss than those with former-smoking donors,” researchers wrote in their paper.

But more than 90,000 Americans are waiting for a kidney transplant, according to the United Network for Organ Sharing.

Because of this, smokers should not be automatically ruled out as donors, the researchers said.

“Living donor transplantation remains a highly beneficial treatment option and smoking history alone should not automatically disqualify an otherwise suitable donor,” McBee said.

More information

The United Network for Organ Sharing has more on kidney transplants in the United States.

SOURCES: University of California-Davis, news release, Oct. 12, 2026; Kidney360, Oct. 1, 2026