Background: PAK transplantation has historically been perceived to be inferior to Simultaneous Pancreas and Kidney (SPK) transplantation with respect patient and pancreas allograft survival. However, some single center studies show excellent outcomes of PAK recipients comparable to that of SPK recipients. The current analysis examines national level data to further explore PAK patient and graft survival.
Methods: Kaplan-Meier and Cox proportional Hazard models were used to analyze OPTN data from 1995-2010 to determine if receiving a transplant was more beneficial compared to staying on the waitlist. The analysis compared adult candidates and recipients for Pancreas Transplant Alone (PTA), PAK, and SPK procedures.
Results: Kaplan-Meier analysis among PAK recipients demonstrated that receiving a pancreas after kidney is associated with an increased kidney graft survival over 5 years compared to recipients who only received a kidney and no pancreas. This pattern was observed regardless of the type of kidney transplant received (i.e. living donor vs. deceased donor). Moreover, receiving a living donor kidney was associated with increased pancreas graft survival over 5 years compared to receiving a deceased donor kidney. With regard to mortality after transplant vs. remaining on the waiting list (WL),Figure 1 shows the hazard ratio (HR) of receiving a transplant compared to staying on the waitlist by procedure type, and receiving a sequential PAK transplant compared to a uremic patient on the SPK waiting list not receiving a transplant (4th panel). An HR < 1 indicates transplanted recipients have a survival advantage. When PAK transplants are compared to recipients who received a kidney transplant (2nd panel) it appears there is no survival advantage to getting the pancreas transplant. However, PAK transplant recipients who receive both organs have an increased survival advantage compared to uremic candidates who receive neither a pancreas nor a kidney (4th panel). Moreover, compared to uremic diabetic WL patients, SPK and PAK recipients showed similar overall patient survival benefits (compare panel #3 vs. #4).
Conclusion: A successful PAK transplant offers a survival advantage compared to those who receive neither a kidney nor a pancreas transplant, a comparison which has not previously been made which highlights similarities in patient survival outcomes to SPK recipients and the overall benefits of uremic diabetic patients receiving both a pancreas and kidney transplant either sequentially or simultaneously. Furthermore, these data corroborate prior data which suggests receiving a pancreas transplant may have a protective effect on the kidney graft.