Validation of the Pancreatic Donor Risk Index in Simultaneous Pancreas-Kidney Transplantation Performed in Córdoba Hospital From 2000 to 2015

Outcome-Orientated Organ Allocation-A Composite Risk Model for Pancreas Graft Evaluation and Acceptance

Background: Pancreas transplantation (PTX) remains the most effective treatment to prevent long-term complications and provide consistent euglycemia in patients with endocrine pancreatic insufficiency, mainly in type I diabetic patients. Considering early graft loss (EGL) and the perioperative complication rate, an optimal risk stratification based on donor risk factors is paramount. Methods: In our single-center study, we retrospectively assessed the risk factors for EGL and reduced graft survival in 97 PTXs (82 simultaneous pancreas and kidney [SPK], 11 pancreases transplanted after kidney [PAK] and 4 pancreases transplanted alone [PTA]) between 2010 and 2021. By statistically analyzing the incorporation of different donor risk factors using the Kaplan-Meier method and a log-rank test, we introduced a composite risk model for the evaluation of offered pancreas grafts. Results: The overall EGL rate was 6.5%. In the univariate analysis of donor characteristics, age > 45 years, BMI > 25 kg/m2, lipase > 60 U/L, cerebrovascular accident (CVA) as the cause of death, mechanical cardiopulmonary resuscitation (mCPR), cold ischemia time (CIT) > 600 min and retrieval by another center were identified as potential risk factors; however, they lacked statistical significance. In a multivariate model, age > 45 years (HR 2.05, p = 0.355), BMI > 25 kg/m2 (HR 3.18, p = 0.051), lipase > 60 U/L (HR 2.32, p = 0.148), mCPR (HR 8.62, p < 0.0001) and CIT > 600 min (HR 1.89, p = 0.142) had the greatest impact on pancreas graft survival. We subsumed these factors in a composite risk model. The combination of three risk factors increased the rate of EGL significantly (p = 0.003). Comparing the pancreas graft survival curves for ≥3 risk factors to <3 risk factors in a Kaplan-Meier model revealed significant inferiority in the pancreas graft survival rate (p = 0.029). Conclusions: When evaluating a potential donor organ, grafts with a combination of three or more risk factors should only be accepted after careful consideration to reduce the risk of EGL and to significantly improve outcomes after PTX.

Pancreas Transplantation Outcome Predictions-PTOP: A Risk Prediction Tool for Pancreas and Pancreas-Kidney Transplants Based on a European Cohort

Background

For patients with complicated type 1 diabetes having, for example, hypoglycemia unawareness and end-stage renal disease because of diabetic nephropathy, combined pancreas and kidney transplantation (PKT) is the therapy of choice. However, the shortage of available grafts and complex impact of risk factors call for individualized, impartial predictions of PKT and pancreas transplantation (PT) outcomes to support physicians in graft acceptance decisions.

Methods

Based on a large European cohort with 3060 PKT and PT performed between 2006 and 2021, the 3 primary patient outcomes time to patient mortality, pancreas graft loss, and kidney graft loss were visualized using Kaplan-Meier survival curves. Multivariable Cox proportional hazards models were developed for 5- and 10-y prediction of outcomes based on 26 risk factors.

Results

Risk factors associated with increased mortality included previous kidney transplants, rescue allocations, longer waiting times, and simultaneous transplants of other organs. Increased pancreas graft loss was positively associated with higher recipient body mass index and donor age and negatively associated with simultaneous transplants of kidneys and other organs. Donor age was also associated with increased kidney graft losses. The multivariable Cox models reported median C-index values were 63% for patient mortality, 62% for pancreas loss, and 55% for kidney loss.

Conclusions

This study provides an online risk tool at https://riskcalc.org/ptop for individual 5- and 10-y post-PKT and PT patient outcomes based on parameters available at the time of graft offer to support critical organ acceptance decisions and encourage external validation in independent populations.

Utilization of the Pancreas From Donors With an Extremely High Pancreas Donor Risk Index: Report of the National Registry of Pancreas Transplantation

Pancreas transplants from expanded criteria donors are performed widely in Japan because there is a shortage of brain-dead donors. However, the effectiveness of this strategy is unknown. We retrospectively studied 371 pancreas transplants to evaluate the possibility of pancreas transplantation from expanded criteria donors by the Pancreas Donor Risk Index (PDRI). Patients were divided into five groups according to quintiles of PDRI values (Q1-Q5). The 1-year pancreas graft survival rates were 94.5% for Q1, 91.9% for Q2, 90.5% for Q3, 89.3% for Q4, and 79.6% for Q5, and were significantly lower with a lower PDRI (p = 0.04). A multivariate analysis showed that the PDRI, donor hemoglobin A1c values, and pancreas transplantation alone significantly predicted 1-year pancreas graft survival (all p < 0.05). Spline curve analysis showed that the PDRI was incrementally associated with an increased risk of 1-year graft failure. In the group with a PDRI ≥ 2.87, 8/56 patients had graft failures within 1 month, and all were due to graft thrombosis. The PDRI is a prognostic factor related to the 1-year graft survival rate. However, pancreas transplantation from high-PDRI donors shows acceptable results and could be an alternative when the donor pool is insufficient.

Validating the US pancreas donor risk index in a Norwegian population, a retrospective observational study

OBJECTIVES

Despite advances in immunosuppression and surgical technique, pancreas transplantation is still associated with a significant graft loss rate. The Pancreas Donor Risk Index (PDRI) is a pre-transplant scoring tool derived from a US population. We sought to validate the PDRI in a Norwegian population.

METHODS

We retrospectively retrieved donor data for 344 pancreas transplants undertaken in Norway between 2000 and 2019, utilising the Scandiatransplant database, and matched these to the respective recipients. The PDRI score was calculated for each transplanted pancreas, these were then stratified into quintiles. The association between the PDRI quintiles and 1-year graft survival was calculated, and this was repeated for the different types of pancreas transplantation. The association between PDRI as a continuous variable, and graft survival was determined. Donor and recipient data were compared to the original US population.

RESULTS

The overall 1-year graft survival was 82.7%. There were no significant differences in survival between the different PDRI quintiles. When viewed as a continuous variable, increased PDRI score was not associated with decreased graft survival. Significant differences between the Norwegian and US populations were found.

CONCLUSIONS

When applied to a Norwegian population, the PDRI score was unable to predict 1-year graft survival.

Pancreas Donor Risk Index and Preprocurement Pancreas Suitability Score for Prediction of Pancreas Transplant Outcomes

OBJECTIVES

The Pancreas Donor Risk Index and Preprocurement Pancreas Suitability Score were designed to assist in the evaluation of pancreases for transplant. Preprocurement Pancreas Suitability Score <17 and PancreasDonor Risk Index ≤1.57 were deemed ideal.We aimed to determine the ability ofthese scores to predict pancreas transplant outcomes.

MATERIALS AND METHODS

The Pancreas Donor Risk Index and the Preprocurement Pancreas Suitability Score were retrospectively calculated from a prospectively maintained database of consecutive pancreas transplants performed during a 13-year period (December 2004 to November 2017). Outcomes measuredwere rejection rate, graft and patient survival, and duration of hospital stay.

RESULTS

Of 159 pancreas transplants (108 simultaneous pancreas and kidney transplants, 33 pancreas after kidney transplants, 18 pancreas-only transplants), full data were available for 155 (97%) to calculate Pancreas Donor Risk Indexes and 129 (81%) to calculate Preprocurement Pancreas Suitability Scores. Fortyseven patients (30%) experienced at least 1 episode of acute rejection. We calculated Pancreas Donor Risk Indexes for 155 patients, and 19 (23%) and 27 (38%) were in the ≤1.57 and >1.57 groups, respectively (P = .047). We calculated Preprocurement Pancreas Suitability Scores for 129 patients, and 12 (21%) and 27 (32%) were in the <17 and ≥17 groups, respectively (P = .202). Donor age and recipientfemale sex were the main predictors forrejection (binary logistic regression, P < .05). One-year graft survival rates were 95% and 81% forthe ≤1.57 and >1.57 PancreasDonor Risk Index groups,respectively, and 95% and 80% forthe <17 and ≥17 Preprocurement Pancreas Suitability Score groups, respectively (not significant).

CONCLUSIONS

Pancreas Donor Risk Index and Preprocurement Pancreas Suitability Score were not helpful to predict graft/patient survival in our population. A higher Pancreas Donor Risk Index was associated with higher risk of graft rejection. Further studies with larger cohorts are required.

Risk indices predicting graft use, graft and patient survival in solid pancreas transplantation: a systematic review

BACKGROUND

Risk indices such as the pancreas donor risk index (PDRI) and pre-procurement pancreas allocation suitability score (P-PASS) are utilised in solid pancreas transplantation however no review has compared all derived and validated indices in this field. We systematically reviewed all risk indices in solid pancreas transplantation to compare their predictive ability for transplant outcomes.

METHODS

Medline Plus, Embase and the Cochrane Library were searched for studies deriving and externally validating risk indices in solid pancreas transplantation for the outcomes of pancreas and patient survival and donor pancreas acceptance for transplantation. Results were analysed descriptively due to limited reporting of discrimination and calibration metrics required to assess model performance.

RESULTS

From 25 included studies, discrimination and calibration metrics were only reported in 88% and 38% of derivation studies (n = 8) and in 25% and 25% of external validation studies (n = 12) respectively. 21 risk indices were derived with mild to moderate ability to predict risk (C-statistics 0.52-0.78). Donor age, donor body mass index (BMI) and donor gender were the commonest covariates within derived risk indices. Only PDRI and P-PASS were subsequently externally validated, with variable association with post-transplant outcomes. P-PASS was not associated with pancreas graft survival.

CONCLUSION

Most of the risk indices derived for use in solid pancreas transplantation were not externally validated (90%). PDRI and P-PASS are the only risk indices externally validated for solid pancreas transplantation, and when validated without reclassification measures, are associated with 1-year pancreas graft survival and donor pancreas acceptance respectively. Future risk indices incorporating recipient and other covariates alongside donor risk factors may have improved predictive ability for solid pancreas transplant outcomes.

Pancreas Transplantation from Donors after Circulatory Death: an Irrational Reluctance?

PURPOSE OF REVIEW

Beta-cell replacement is the best therapeutic option for patients with type 1 diabetes. Because of donor scarcity, more extended criteria donors are used for transplantation. Donation after circulatory death donors (DCD) are not commonly used for pancreas transplantation, because of the supposed higher risk of complications. This review gives an overview on the pathophysiology, risk factors, and outcome in DCD transplantation and discusses different preservation methods.

RECENT FINDINGS

Studies on outcomes of DCD pancreata show similar results compared with those of donation after brain death (DBD), when accumulation of other risk factors is avoided. Hypothermic machine perfusion is shown to be a safe method to improve graft viability in experimental settings. DCD should not be the sole reason to decline a pancreas for transplantation. Adequate donor selection and improved preservation techniques can lead to enhanced pancreas utilization and outcome.

Risk Indices in Deceased-donor Organ Allocation for Transplantation: Review From an Australian Perspective

Over the last decade, organ donation and transplantation rates have increased in Australia and worldwide. Donor and recipient characteristics for most organ types have generally broadened, resulting in the need to consider more complex data in transplant decision-making. As a result of some of these pressures, the Australian software used for donor and recipient data management is currently being updated. Because of the in-built capacity for improved data management, organ allocation processes will have the opportunity to be significantly reviewed, in particular the possible use of risk indices (RIs) to guide organ allocation and transplantation decisions. We aimed to review RIs used in organ allocation policies worldwide and to compare their use to current Australian protocols. Significant donor, recipient, and transplant variables in the indices were summarized. We conclude that Australia has the opportunity to incorporate greater use of RIs in its allocation policies and in transplant decision-making processes. However, while RIs can assist with organ allocation and help guide prognosis, they often have significant limitations which need to be properly appreciated when deciding how to best use them to guide clinical decisions.

The Role of Pre-Procurement Pancreas Suitability Score (P-PASS) and Pancreas Donor Risk Index (PDRI) in the Outcome of Simultaneous Pancreas and Kidney or Pancreas After Kidney Transplantation

Background

The pre-procurement pancreas suitability score (P-PASS) and the pancreas donor risk index (pDRI) are established predictive scores for graft survival and patient outcome following pancreatic transplantation. This retrospective study aimed to evaluate the predictive value of P-PASS and pDRI following simultaneous pancreas and kidney (SPK) transplantation, or pancreas after kidney (PAK) transplantation, and the clinical impact of donor-specific factors on the postoperative graft and recipient outcome at a single transplant center.

Material/Methods

The study included 105 patients who underwent SPK (n=104) or PAK (n=4) between 2000 and 2017. Donor-specific and recipient-specific parameters were recorded. Kaplan-Meier analysis and Cox regression analysis were used to assess the outcome after transplantation.

Results

Overall, the mean 1-year and 5-year pancreas graft survival and patient survival rates were 78.7% and 93.2%, and 76.9% and 90.0%, respectively. The postoperative outcome in patients with a P-PASS score of <17 was not significantly different when compared with patients with a score of ≥17. A P-PASS score of ≥17 was significantly associated with early pancreas graft loss (p=0.04). There was no significant difference in postoperative outcome between patients with high pDRI and low pDRI. Smoking of donor (p=0.046) was a risk factor and coronary heart disease of recipient (p=0.003) had a significant effect on survival of pancreas graft.

Conclusions

This study showed that P-PASS and pDRI were not reliable predictors of outcome after pancreas transplantation and that specific characteristics of the donor and recipient must be evaluated when predicting the outcome of pancreas transplantation.

Pancreas Donor Risk Index but Not Pre-Procurement Pancreas Allocation Suitability Score Predicts Pancreas Graft Survival: A Cohort Study from a Large German Pancreas Transplantation Center

Background

The pre-procurement pancreas allocation suitability score (P-PASS) was introduced to support clinical decision-making and ultimately expand the currently insufficient pancreas donor pool. The pancreas donor risk index (PDRI) can be used at the time of organ offering to predict one-year graft survival. Thus, this study aimed to analyze the validity of the PDRI and P-PASS in a large German transplant center.

Material/Methods

From 2002 to 2015, we performed 327 pancreas transplantations at our center. P-PASS and PDRI were calculated for 322 patients. To evaluate the pancreas graft survival, the patient cohort was divided into 2 P-PASS (<17, n=115 and ≥17, n=207) and 3 PDRI groups (<1, n=87; 1–1.5, n=133; and >1.5, n=102). Kaplan-Meier and Cox regression analyses were performed. We also examined differences regarding early pancreas graft failure for both scores using the chi-square test.

Results

The PDRI was associated with pancreas graft survival in the univariate analysis (p=0.023). In the multivariate analysis, a PDRI >1.5 was associated with significantly decreased graft survival (hazard ratio=1.792, 95% confidence interval=1.10–2.90, p=0.018). The P-PASS showed no significant association (p=0.081) with pancreas graft survival in the Kaplan-Meier survival analysis. There were significantly more early pancreas graft losses in the P-PASS ≥17 group (p=0.025).

Conclusions

Our results showed an association between P-PASS ≥17 and early pancreas graft failure. However, this does not apply to long-term pancreas graft survival; the PDRI proved to be a better tool for this, and PDRI values >1.5 were associated with significantly worse outcomes after pancreas transplantation.

Usefulness of Pancreas Donor Risk Index and Pre-Procurement Pancreas Allocation Suitability Score: Results of the Polish National Study

Background

Pre-procurement pancreas suitability score (P-PASS) and pancreas donor risk (PDRI) index are scoring systems believed to predict suitability of pancreatic grafts. Most European countries and the United States apply PDRI, while Poltransplant keeps using P-PASS: more than 16 points raises a red flag for graft use. Recent data discourage use of PDRI to predict pancreas graft survival. The aim of the present study was to assess PDRI and P-PASS as predictors of transplanted pancreas survival in a Polish population.

Material/Methods

From February 1998 to September 2015, 407 pancreas transplantations were performed in Poland: 370 (90.9%) simultaneous pancreas-kidney transplantation and 37 (9.1%) pancreas transplantation alone or pancreas after kidney. The endpoint was death-uncensored 12-month graft survival with satisfactory glycemic control without insulin.

Results

Average P-PASS was 15.9±2.66 and PDRI was 0.96±0.37. Recipients who survived 12 months with good graft function had an average P-PASS score of 15.7 and PDRI of 0.95. Recipients with death-uncensored graft loss had a mean P-PASS of 16.4 and PDRI of 0.99. Univariate analysis revealed donor age, body mass index (BMI), and P-PASS to be significant risk factors for 1-year pancreas graft survival.

Conclusions

P-PASS, but not PDRI, is a reliable tool to predict pancreas graft survival in the Polish population.