P1637UK KIDNEY ALLOCATION SCHEME: APPROPRIATE MATCHING BUT RESOURCE IMPLICATIONS

Background and Aims UK NHSBT kidney matching scheme changed in September 2019, aiming to better match graft and patient survival through stratification of donors and recipients into risk quartiles. We present data on two years of transplants aiming to highlight discrepancies between our unit and the model on which the scheme is based, and the potential implications on service provision of its’ introduction. Method We reviewed all deceased donor transplants in our centre in 2015 and 2016. Recipients and donors were re-classified into the risk index quartiles and endpoint data included inpatient days in first year, 1 year eGFR, survival, imaging, and infection episodes. Comparisons were made with NHSBT literature. Results 196 deceased donor transplants were performed. Distribution of D1-4 kidneys to R1-4 recipients in our cohort did not reflect those presented in the allocation scheme models, with our population skewed toward higher risk R4 category (73.4%), including 55 D4R4 (83% of D4 kidneys), see Figure 1. 2.0% had an age difference between donor and recipient of >25years, and 12.8% 15-25 years, compared with the NHSBT proposed targets of 8% and 20% respectively. Within the R4 group, recipients receiving a D4 graft were associated with a higher rate of DGF (41.7%, vs 23.2% D1-D3 grafts, p=0.009), longer index admission (median 11 days vs 8 days, p=0.038) and more readmissions within the first post-operative year (median 18 vs 11 days, p = 0.005) – Figure 2. D4 grafts demonstrated lower mean eGFR at one year (35.7, vs. 54.8 ml/min, p<0.001), Figure 3. R4 recipients experienced graft loss more frequently (HR 3.4 vs R1-3 (95%CI 0.8-13.9, p=0.12). One-year survival in R4 cohort was 97.8% (four deaths), and 93.8% at 4 years; R1-3 cohort had 100% survival to 4 years; there was no significant impact on R4 patient survival with D4 kidneys vs. D1-D3. Day ward attendances, bacteraemia, and CT imaging events did not differ by R or D category; D4 was associated with higher rates of transplant ultrasound (5.6 vs R1-3 4.25, p=0.009), and R4 with higher rates of urinary tract infection (3.6 vs R1-3 1.5, p=0.03). Conclusion Firstly, our transplant population is weighted to higher risk R4 recipients; secondly, intended principals of the allocation scheme are already largely being observed. Thirdly, our data does suggest that increasing R4D4 transplants will have a significant impact on transplant centres, with resource burden primarily within the first year. But despite poorer graft function, patient survival appears to be equivalent and improved matching may in the longer term reduce need for re-implantation as the scheme intends.