J LING1, T COUGHLAN1, K POLKINGHORNE1, J KANELLIS1
1Monash Medical Centre, Clayton, Australia
Aim: To critically appraise the ability of risk indices (RI) to predict pancreas transplantation (PTx) outcomes.
Background: RI using donor/recipient characteristics assist in organ allocation and acceptance decisions by predicting post-transplant outcomes such as graft/patient survival. While RI have been derived for use in PTx, they are not widely utilised.
Methods: Medline Plus, Embase via OVID and the Cochrane Library were searched for studies describing derivation or use of RI in PTx up to 1st November 2017. Primary outcomes of interest were pancreas graft and patient survival, with secondary outcomes of organ acceptance.
Results: 2418 abstracts were screened with 32 studies entering full-text analysis. 10/32 studies derived 23 models predicting outcomes of interest. 2/23 models were RI that were externally validated in 24/32 studies. 21/23 models were derived without external validation. RI were the pancreas donor risk index (PDRI) and the pancreas pre-procurement score (P-PASS). Apart from their covariates, common covariates in other models included recipient age/BMI, dialysis duration pre-transplant, history of diabetes, transplant type, and immunosuppression regimen. Risk of bias was variable and generally high. Deficiencies in reporting included handling of missing data, covariates and follow-up duration. Discrimination and calibration was only described in 10 and 2 studies respectively. Heterogeneity was present in model derivation method, outcome definitions and study results. PDRI was significantly associated with pancreas graft survival in 9 studies and P-PASS was significantly associated with pancreas donor acceptance in 3 studies.
Conclusions: RI in PTx have not been widely validated apart from P-PASS and PDRI. Within a validated cohort, PDRI (as a categorical variable) and P-PASS have value in predicting pancreas graft survival and in predicting donor pancreas acceptance respectively.
Renal Fellow at Monash Medical Centre