The economic benefit of allocation of kidneys based on cross-reactive group matching

Recently the United Network for Organ Sharing (UNOS) began a pilot study to evaluate prospectively the merits of an allocation of cadaveric kidneys based on broader classes of HLA antigens, called cross-reactive groups (CREG). The objectives of the pilot study consider patient outcomes, but not the potential economic impact of a CREG-based allocation. This study predicts the impact of a CREG-based local allocation of cadaveric kidneys on 3-year Medicare payments and graft survival.

The UNOS renal transplant registry was merged to Medicare claims data for 1991-1997 by the United States Renal Data System. Average accumulated Medicare payments and graft survival up to 3 years posttransplant for first cadaveric renal transplant recipients were stratified by cross-reactive group mismatch categories. The economic impact was defined as the difference in average 3-year costs per transplant between the current and proposed allocation algorithms. Average 3-year costs were computed as a weighted average of costs, where the weights were the actual and predicted distributions of transplants across cross-reactive group categories.

Results suggest that an organ allocation based on cross-reactive group matching criteria would result in a 3-year cost savings of $1,231 (2%) per transplant, and an average 3-year graft survival improvement of 0.6%.

Cost savings and graft survival improvements can be expected if CREG criteria were to replace current criteria in the current allocation policy for cadaveric kidneys, although the savings appear to be smaller than may be achievable through expanded HLA matching.