December 2, 2003 People with brittle or complicated diabetes who receive either a pancreas transplant alone or a pancreas transplant after a kidney transplant have a lower survival rate than similar patients waiting for the same type of pancreas transplant. However, recipients of a simultaneous pancreas-kidney (SPK) transplant, who have diabetes as well as kidney failure, have better 1- and 4-year survival rates than those waitlisted for that surgery, according to a study published in The Journal of the American Medical Association on December 3, 2003.
The 1-year and 4-year survival rates for those receiving a pancreas transplant alone were 97 percent and 85 percent respectively, while those on the waiting list for a pancreas alone had a better survival rate: 98 percent and 92 percent respectively. Likewise, people waitlisted for a pancreas transplant after having a kidney transplant had better survival at 1 and 4 years—97 percent and 88 percent—than the group who actually had the surgery--95 percent and 85 percent. This is in contrast to SPK recipients whose survival at 1 and 4 years post-transplant was better than for those on the waiting list: 94 percent and 88 percent survival compared to 93 percent and 64 percent.
While a randomized, controlled trial is considered the most scientifically rigorous way to compare long-term outcomes, such a trial is costly and often impractical. In this case, researchers chose instead to compare survival rates for those who received a pancreas transplant to similar patients waiting for the same surgery. They analyzed the risk of mortality for 11,572 patients with diabetes listed for pancreas transplantation in 124 medical centers by the United Network for Organ Sharing between January 1, 1995 and December 31, 2000. Patients were subgrouped by procedure: SPK, pancreas alone, and pancreas after kidney transplant. Of the 6,595 patients receiving a transplant, 5,379 received an SPK, 378 received a pancreas transplant alone, and 838 received a pancreas after kidney transplant.
People with diabetes who have good kidney function but frequent episodes of dangerously high or low blood glucose are undergoing solitary pancreas transplantation with increasing frequency. Between 1995 and 2002, the annual number of such surgeries increased five-fold. In contrast, the number of SPK transplants, a more common procedure reserved for people with diabetes and kidney failure, remained stable from 1995 to 2002.
Although pancreas transplantation often results in improved blood glucose control, both the surgery and the immunosuppression needed to prevent rejection of the donated organ pose significant risks. The surgery itself entails a higher risk of complications than other abdominal organ transplant procedures, the authors note. And anti-rejection drugs such as FK506, sirolimus, cyclosporine, and azathioprine, which are used in various combinations, often cause side effects such as fatigue, infection, and mouth sores.
Patients with both diabetes and kidney failure have a high annual death rate. An SPK transplant improves 1- and 4-year survival rates in these patients despite a higher risk of death in the first 3 months after the surgery. In contrast, patients awaiting a solitary pancreas transplant—who have good kidney function either because diabetes has not destroyed their kidneys or because they received a kidney transplant before the planned pancreas transplant—have a much better prognosis.
“Steady improvements in state-of-the-art treatments have resulted in a much better prognosis for people with diabetes than is generally appreciated,” said lead author Dr. David Harlan, who heads the Transplantation and Autoimmunity Branch of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK ). “Many patients with successful pancreas transplants savor the day they were freed from the constant need to control their diabetes by frequently checking their blood sugars, injecting insulin, and closely monitoring their diet and exercise. Yet, when we used survival as the yardstick, we found that aggressive intervention with transplant surgery and immunosuppression does not compare favorably to more conservative management, except in the case of simultaneous pancreas kidney transplant.”
The study was conducted by researchers in NIDDK's Transplantation and Autoimmunity Branch, the United Network for Organ Sharing, and the University of Pittsburgh. The work was supported by the NIDDK, one of the National Institutes of Health under the Department of Health and Human Services.
Contact:
NIDDK (301) 496-3583
Joan Chamberlain
Jane DeMouy
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