Diabetes raises mortality risk after solid-organ transplantation

People with an organ transplant who develop or have existing diabetes are more likely to die than those without diabetes, according to a comprehensive analysis of solid-organ transplant recipients, which is being presented Saturday at ENDO 2026, the Endocrine Society's annual meeting in Chicago, Ill.

Diabetes is a common chronic disease affecting about 830 million people worldwide. Organ transplant recipients have a higher risk of developing and worsening diabetes, which can affect both their lifespan and the success of the transplant.

We studied how diabetes affects longevity in people post solid-organ transplant and found both ongoing and new-onset diabetes increased risk of mortality. Until now, the magnitude of diabetes' impact on survival has not been compared head-to-head across major organ transplants. This research helps quantify the impact of diabetes across organ transplant types."

Mishal Ali, study lead, University of Chicago in Chicago, Ill.

The researchers looked at more than 800,000 Americans who received a kidney, liver, heart, lung, pancreas or intestine transplant between 2003 and 2021. They compared two groups: people who already had diabetes when they received their new organ, and people who got diabetes for the first time after their surgery.

They found both groups were more likely to die than recipients without diabetes. For people getting a new liver or heart, newly developed diabetes was about as dangerous as having had diabetes for years. For people getting a new kidney, it was still dangerous, but somewhat less so than having diabetes from the start. The association of diabetes diagnosis and type of organ failure varied almost 7-fold based on organ type.

In the group of recipients who already had diabetes, kidney recipients had the highest risk by far. Heart and liver recipients had a smaller increase in risk compared to kidney. Lung recipients had the smallest increase in risk. The gap was small at one year, around one to two more deaths per 100 patients for kidney, liver, and heart and almost no difference for lung recipients. This changed with time: at 10 years after transplant almost 24 more out of every 100 kidney recipients with diabetes had died.

Among recipients who developed diabetes after surgery, kidney and heart recipients had the highest risk of death. Liver recipients had a slightly smaller increase, and lung recipients had the smallest risk increase.

"Transplant providers should monitor closely for current and new-onset diabetes. Because of the differential effect of diabetes on recipients by organ type, prevention and management will need to be tailored," said senior author and transplant hepatologist Alan L. Hutchison, M.D., Ph.D., of UChicago Medicine in Chicago, Ill. "Patients and their families can ask transplant providers more specific questions about diabetes risk, both before surgery and in the months after, and decide together whether extra check-ups or treatment make sense."