Addressing the increasingly unmet demand for transplantable kidneys in the U.S. requires creativity due to legislation that prohibits buying and selling organs. To increase the number of successful transplants that take place, transplant centers have begun to implement kidney exchange programs. In Chapter 1, I first estimate the number of additional transplants generated by kidney exchanges by analyzing how the probability of receiving an exchange transplant affects the probability that a patient experiences other transplant outcomes, including death while waiting. To do this, I create a novel measure of exchange prevalence that exploits variation in exchange activity across time and transplant centers, as well as the importance of patient proximity to centers performing exchanges. I find that 6.2 of every 10 exchange transplants represent living donor transplants that would not have occurred in the absence of exchange. I also find that a ten percentage point increase in the probability of receiving an exchange transplant increases one-year and two-year graft survival by roughly 2.1 percent, and reduces waiting list registration duration by 10 percent.Since one of the purported benefits of kidney exchange is that it increases access to living donor transplants for hard-to-match patients, and given existing concerns in the transplant community about demographic disparities in transplant access and outcomes, in Chapter 2 I analyze the extent to which exchanges have differential impacts on transplant outcomes across patients of various blood types, levels of sensitivity to foreign organs, races, ages, and levels of education. To estimate the effects of interest, I exploit the importance of patient proximity to exchange centers in order to generate exogenous variation in the probability of receiving a transplant via exchange. The first main finding is that rising exchange prevalence tends to benefit harder-to-match blood types the least with respect to both quantity and quality of transplants, though they seem to have larger positive impacts on patients with higher (compared to lower) levels of senstitivity to foreign organs. The second main finding is that black patients and older patients experience the smallest gains in transplant quantity as exchange prevalence increases relative to other race and age groups, respectively.Because geography plays a key role in deceased donor organ allocation, shocks to the local supply of organs will likely affect transplant waitlists. In Chapter 3, Stacy Dickert-Conlin, Todd Elder, and I use data on transplant recipients from the Scientific Registry of Transplant Recipients to assess whether shifts in the supply of organs arising from changes in motorcycle helmet laws affect the behavior and outcomes of transplant candidates. We find that, following repeals of statewide motorcycle helmet laws, the local supply of transplantable organs from donors killed in motor vehicle accidents increases by nearly 20 percent. These supply shocks induce strong responses from transplant candidates: inflows to local transplant waitlists increase by 12 percent in the years following the repeal. These inflows are especially pronounced among those who live outside the local area, implying that in the absence of a formal pricing mechanism, waiting times for organs are the relevant “price” determining listing decisions. In addition, transplants from living donors decline following supply shocks, suggesting that the availability of transplants from living and deceased donors influence candidates’ decisions to seek organs from living donor. Finally, the average transplant is more successful following the increase in transplantable organs, as measured by the probability of the transplanted organ surviving at least one year. This quality improvement may explain the dramatic increases in wait lists to the areas with more organs.
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