State-Level Variation in Waitlist Mortality and Transplant Outcomes Among Patients Listed for Heart Transplantation in the US From 2011 to 2016

Abstract

Importance: Little is known about geographic variation in the outcomes of adult patients listed for heart transplantation in the US. Identifying the patterns and extent of variation is important to minimize disparity in outcomes.

Objective: To evaluate the geographic patterns, extent, and factors associated with state-level variation in outcomes of adult patients listed for heart transplantation in the US.

Design, setting, and participants: This nationwide retrospective cohort study used data from the United Network for Organ Sharing database to identify adult patients listed for heart transplantation at status 1A between January 1, 2011, and December 31, 2016. Patients were followed up until March 31, 2018. Data were analyzed from November 1, 2019, to September 19, 2020.

Main outcomes and measures: The study evaluated state-level variation in the 3 main organ transplant measures: waitlist mortality, transplant rate, and risk-adjusted 1-year graft survival. The rate of death while on the waitlist and the rate of transplant were calculated for each state per 1000 waitlist person-days listed at status 1A over the study period. Risk-adjusted 1-year graft survival was calculated based on the Scientific Registry of Transplant Recipients risk-adjustment model. State-level variation in each outcome measure was evaluated via multivariable-adjusted models.

Results: Across 50 states and the District of Columbia, a total of 15 036 patients (mean [SD] age, 52 [13] years; 3531 women [24%]; 9626 White [64%]) were listed at status 1A for adult heart transplantation between 2011 and 2016. Of those, 2146 patients (14.3%) died while on the waitlist, and 10 982 patients (73.0%) received transplants. Among those who received transplants, the median time on the waitlist was 31 days (interquartile range, 13-61 days). State-level outcomes ranged from 1.0 to 7.8 deaths per 1000 waitlist person-days for waitlist mortality, 5.6 to 34.5 transplants per 1000 waitlist person-days for transplant rate, and 87% to 92% for risk-adjusted 1-year graft survival. In a comparison of the highest and lowest quartiles, significant state-level variation was found in waitlist mortality (hazard ratio [HR], 1.53; 95% CI, 1.27-1.86), transplant rate (HR, 1.57; 95% CI, 1.31-1.87), and 1-year graft survival (odds ratio, 2.07; 95% CI, 1.64-2.62).

Conclusions and relevance: The study's findings indicate that significant state-level variation exists in the outcomes of patients listed for heart transplantation in the US. Identifying and addressing the factors associated with these geographic variations in outcomes is important to ensure a fair allocation system.

Figure 1.. State-Level Outcomes

A, Variation in waitlist person-days among patients listed at status 1A for heart transplant in the US. The waitlist burden ranged from 514 waitlist person-days in Alaska to 113 147 waitlist person-days in New York (national median, 7489 waitlist person-days; IQR, 3844-19 105 waitlist person-days). B, Waitlist mortality per 1000 waitlist person-days at status 1A. Estimates ranged from 1 death per 1000 waitlist person-days in Nebraska and Wyoming to 7.8 deaths per 1000 waitlist person-days in Alaska (national median, 2.9 deaths per 1000 waitlist person-days; IQR, 1.8-3.7 deaths per 1000 waitlist person-days). C, Transplant rates per 1000 waitlist person-days at status 1A. Estimates ranged from 5.6 transplants per 1000 waitlist person-days in Vermont to 34.5 transplants per 1000 waitlist person-days in Kansas (national median, 15.7 transplants per 1000 waitlist person-days; IQR, 9.2-21.3 transplants per 1000 waitlist person-days). D, Risk-adjusted rates of 1-year graft survival. Survival estimates ranged from 87% in Nevada, Arkansas, Idaho, Wyoming, and Louisiana to 92% in Hawaii (national median, 89%; IQR, 88%-89%).

Figure 2.. Cumulative Incidence of Waitlist Deaths and Transplant Events

A, Cumulative incidence of waitlist deaths, stratified by state-level quartile (only the first 300 days of follow-up is shown). The median time from waitlist entry to death ranged from 13 days for the highest quartile to 30 days for the lowest quartile (national median, 20 days; IQR, 7-44 days). B, Cumulative incidence of transplant events, stratified by state-level quartile (only the first 300 days of follow-up is shown). The median time from waitlist entry to transplant ranged from 24 days for the highest quartile to 31 days for the lowest quartile (national median, 31 days; IQR, 13-61 days).