Delayed Graft Function in Simultaneous Pancreas-Kidney Transplantation: A Marker of Recipient Risk, Rather Than Graft Outcomes.

The long-term impact of kidney delayed graft function (DGF) following simultaneous pancreas-kidney (SPK) transplantation, and its frequency in the post-kidney allocation system (KAS 250) era, remains incompletely understood. We analyzed adult SPK recipients (2014-2025) in the Scientific Registry of Transplant Recipients, stratified by DGF status, with follow-up censored at 7.5 years. Multivariable logistic regression identified predictors of DGF, and Cox proportional hazards models evaluated associations with kidney and pancreas death-censored graft survival and recipient survival. Among 5,474 recipients, 472 (8.6%) developed DGF. Independent predictors included pre-transplant dialysis (OR 3.98, 95% CI 2.43-6.52; p<0.001), longer cold ischemia time (OR 1.03 per hour, 95% CI 1.01-1.05; p=0.01), and transplantation in the post-KAS 250 era (OR 1.53, 95% CI 1.22-1.92; p<0.001). DGF was not associated with acute rejection or kidney (HR 0.92, 95% CI 0.62-1.37; p=0.69) or pancreas graft survival (HR 1.27, 95% CI 0.88-1.82; p=0.20). In contrast, DGF was independently associated with worse recipient survival (HR 1.66, 95% CI 1.24-2.21; p<0.001), including in analyses conditioned on one-year pancreas and kidney graft survival (HR 1.52, 95% CI 1.03-2.23; p=0.034). DGF represents an important marker of post-transplant risk with implications for long-term recipient outcomes.