Pancreas Transplants Raise Death Risk
Diabetics survive longer under conventional therapy
WEDNESDAY, Dec. 3, 2003 (HealthDayNews) -- People with diabetes who received a pancreas transplant seem to have lower survival rates than patients who remained on the waiting list while receiving conventional therapy.
This seemingly paradoxical finding is reported in the Dec. 3 issue of the Journal of the American Medical Association.
Pancreatic transplantation is usually considered a "last resort" for people with intractable diabetes. But because treatments for diabetes are advancing rapidly, diabetes that seems obstinate may actually be amenable to lifestyle and medication treatments. As a result, transplantation is a controversial issue.
Whereas most people needing a heart or liver transplant will die without it, people can live without getting a new pancreas.
Nevertheless, between 1995 and 2002, the annual number of pancreas transplants in people with diabetes increased fivefold. In the same period, the number of combination pancreas-kidney transplants stayed stable. These simultaneous transplants are usually given to people who have kidney failure and are more likely to die without intervention.
People who have a successful pancreas transplant are able to come off insulin, but they need to take immunosuppressant drugs for the rest of their lives to make sure their bodies don't reject the donated organ.
"It's incorrect for a patient with diabetes to think, 'If I get this transplant, that's that,'" says study author Dr. David M. Harlan, head of the transplant and autoimmunity branch at the National Institute of Diabetes and Digestive and Kidney Diseases. "There's a tail to that treatment -- and that tail is they have to take immunosuppressive drugs forever, and those drugs have significant toxicity. It's a real trade-off."
This retrospective study tried to sort out whether pancreatic transplantation offers any advantage in terms of survival over conventional therapy.
The researchers analyzed data on 11,572 patients with diabetes from 124 transplant centers in the United States. All of the patients were on waiting lists for pancreas transplants between 1995 and 2000.
Of this initial group of people, 6,595 received a pancreas. Of those, 5,379 received a kidney at the same time, 838 received a pancreas after already having received a kidney, and 378 received a pancreas alone.
Over a four-year follow-up period, those who received a pancreas alone had a 57 percent increased risk of death compared with patients on the waiting list. Those who received a pancreas after a kidney had a 42 percent increased risk of death. Those who received both organs at once had a 57 percent decreased risk of death.
The absolute survival rates were nevertheless high. One- and four-year survival rates for those who received a pancreas alone were 96.5 percent and 85.2 percent and, for pancreas-after-kidney, they were 95.3 percent and 84.5 percent. For those on the waiting list for a pancreas alone, the one and four-year survival rates were 97.6 percent and 92.1 percent. For those waiting for a pancreas after a kidney, they were 97.1 percent and 88.1 percent, respectively.
"I think before our paper, the assumption was that there would be excess death in the immediate post-op period, but that the transplant group would catch up, but there didn't appear to be a catch-up in this group," Harlan says.
Because it was retrospective, the study was subject to a number of limitations. Nevertheless, the findings do seem to indicate that a serious decision-making process should be undertaken before going for the operation.
"Even though mortality was higher in the transplant group, the mortality is still low in absolute terms," Harlan says. So patients must ask themselves this question, he suggests: "'Is the 85 percent or greater chance that I'll be able to come off insulin worth the somewhat higher chance that I won't survive it?' It's a tough decision."