Transplant Disparities and Kidney Exchanges: Estimating Quantity and Quality Effects By Patient Blood Type and Sensitization

Kidney exchange programs have been shown to improve the quantity and quality of kidney transplants in the U.S. over the past 15 years. One of the purported benefits of kidney exchange is that it increases access to living donor transplants for hard-to-match patients (i.e. those most likely to die while waiting for another transplant option, all else equal). Moreover, holding exchange transplant quantity and quality fixed, it stands to reason that we achieve the largest welfare gains when such patients are the primary recipients of exchange transplants. In this paper, I analyze the extent to which exchanges have differential impacts on transplant outcomes across patients of different blood types and levels of sensitivity to foreign organs. Exploiting variation in patients' exposure to exchange activity across time and place, I find that exchange has a relatively small beneficial effect on transplant quantity and quality for patients with harder-to-match blood types (types O and B). However, I find that patients who are more sensitized against foreign organs experience larger quantity and quality improvements relative to less-sensitized patients. These findings suggest that exchange programs could generate larger welfare gains by more heavily emphasizing blood type O and B patients in their match runs. Incentivizing participation among compatible patient-donor pairs may be one way to accomplish this goal.