In patients with type 1 diabetes and end-stage renal disease, a combined pancreas/kidney transplant was associated with significantly better 15-year survival than a single kidney graft alone.
Patients who got the simultaneous transplant were 30% more likely to survive to 15 years than were those who received a living donor kidney. Those patients who got a single kidney from a deceased donor, however, were 30% less likely to survive for 15 years after the operation, Dr. Trond Jenssen said at the annual meeting of the European Association for the Study of Diabetes.
The combined graft is the preferred method of treating end-stage renal disease (ESRD) caused by diabetic nephropathy, said Dr. Jenssen of Oslo University. Not all patients are suited for it, however.
“According to the algorithm at our center, if you are older than 55 or too sick, you have to decide between the living and deceased donor single kidney graft. Patients who are younger and have less comorbidity are the ones considered for a combined transplant,” he explained.
Since those who have the dual-organ operation almost always normalize their glycemic values afterward, Dr. Jenssen said, it’s assumed that they will live longer than those who get only a kidney, but studies are divided on the finding.
“The literature over the past 10 years has differed,” he said. Comparing studies among institutions is impossible because of the differences in surgical technique and immunosuppressive regimens; the patient populations can also vary widely.
Oslo University is in a unique place to study the issue, Dr. Jenssen suggested. The facility is the national transplant center, with nearly 30 years of full follow-up data on 630 type 1 diabetes patients who were transplanted for ESRD. All of the patients are followed at least annually and their information is entered into the Norwegian Renal Registry.
“Because patients in Norway tend to be very faithful to their doctors, we have not lost a single one of these to follow-up,” he said.
Of the entire group, 222 received the simultaneous transplants, 171 received a living donor single kidney, and 237 got a deceased donor kidney. Patients who received the simultaneous transplant were younger than the living or deceased single graft groups (41 years vs. 45 and 55 years, respectively).
The study controlled for the evolution of surgical techniques and immunosuppressant regimens. Before 1989, all pancreases were transplanted with occluded ducts. From 1989 to 1999, the exocrine duct drained into the bladder, and since 2000, into the intestine. The pancreas has always been connected to the systemic circulation by the iliac artery and vein.
Before 2000, the immunosuppressive regiment consisted of cyclosporine and azathioprine; afterwards, tacrolimus and mycophenolate. All patients from both eras take a daily dose of prednisone as well.
There was no induction therapy before 2000, Dr. Jenssen said. After that time, patients receiving a single kidney began to receive basiliximab and the dual-transplant patients got thymoglobulin.
The overall 15-year survival rate was 50% in the simultaneous-graft group, 30% in the living donor kidney group, and 12% in the deceased donor kidney group.
Dr. Jenssen presented two regression models. In the first one, which controlled for recipient age, time on dialysis, and the transplant era, patients who got the dual graft were significantly more likely to survive to 15 years than were those who got the single live donor kidney (hazard ratio, 0.70). Patients who received a single deceased donor kidney were 31% less likely to survive (HR, 1.29).
These differences were no longer significant in a second model, which also controlled for donor age, but Dr. Jenssen said that the difference was not clinically meaningful.
Among the 317 patients who died during the study, the most common cause was cardiovascular disease (59%). Infections claimed 15% and malignancy 8%. The remainder of the patients died from causes that he did not specify.
Dr. Jenssen said that he did not control for glycemic index because the hemoglobin A1c test was unavailable during a large part of the follow-up period. He intends to work that into the model eventually, he added.
Dr. Jenssen had no financial disclosures.