Placement on a liver transplant waitlist outside of a patient’s home region can reduce mortality and increase odds of receiving a liver, researchers report in the October issue of Clinical Gastroenterology and Hepatology. Strategies are needed to overcome geographic differences in access to livers for transplantation, which are more likely to affect patients who are minorities, have lower levels of education, or have public insurance.
Access to livers for transplantation is determined not only by medical factors, such as severity of liver dysfunction and comorbidities, but also by social factors, including health literacy, insurance coverage, access to quality care, support systems, and geography.
There are more patients awaiting liver transplantation than available donated organs—a consistent proportion of patients on waitlists die because of a lack of suitable organs. However, the organ shortage does not affect the United States uniformly. There are regional variations in demand for and supply of deceased donor organs.
Many patients therefore travel to areas with a greater probability of liver transplantation. Migrating to a distant transplant center, however, requires considerable effort and expenditure, including costs of travel and lodging for patients and their caregiver(s) during evaluation, perioperative, and post-transplant periods. Therefore, only patients with sufficient means and appropriate health insurance coverage can undergo transplantation at a distant center. Studies have shown that socioeconomic background, race/ethnicity, and level of education affect the practice of placement on multiple lists for liver transplants.
Allison J. Kwong et al evaluated the frequency and patterns of patient migration for liver transplantation on a national scale. They performed a retrospective cohort study of adults registered for primary deceased donor liver transplantation, and used zip code data to calculate the travel distance from a patient’s residence to centers at which they were on a waitlist or received a liver transplant.
There were 104,914 waitlist registrations in the US from January 2004 through December 2016, and 2930 patients (2.8%) were on a waitlist at a distant center (500 miles or more) in addition to their home region. Of the waitlist registrants, 60,985 received liver transplants; of these, 1985 (3.3%) had migrated 500 miles or more for the liver.
There were 14,851 candidates who died while waiting, and 49,297 who received a transplant. The cumulative incidence of death within 1 year after registration was 10.2% among patients who pursued a distant listing, compared with 13.3% among those who had not. Conversely, the cumulative incidences of transplantation were 54.1% for patients with distant listings and 47.3% for patients without.
In a multivariable competing risk analysis, placement on a waitlist at a distant location was associated with a 22% reduction in the risk of death within 1 year. Of the 2930 patients who pursued distant listing, 1985 (67.8%) eventually received a liver transplant at the distant center.
The median model for end-stage liver disease (MELD) score for patients on waitlists in distant regions was 31 in their home donor service area vs 28 in the donor service area at which they were distantly listed (see Figure). For these patients, the median distance traveled from the home zip code to the distant listing center was 1089 miles, compared with 32 miles for patients not on distant waitlists.
Placement on a distant waitlist and migration were associated with non-black race, non-Medicaid payer, residence in a higher income area, and education beyond high school. Waitlist registrants with alcoholic liver disease, hepatitis C, or hepatocellular carcinoma were less likely to pursue liver transplantation at a distant center, whereas patients with autoimmune, cholestatic, or metabolic liver diseases were more likely.
Patients who migrated for liver transplants were more likely to undergo transplantation at a high-volume center (more than 70 transplants per year). The donor livers they received were more likely to be regionally or nationally shared, to be from donors after cardiac death rather than from brain death (8.3% vs 5.4%), and to have higher donor risk indices (1.51 vs 1.46). Living donor liver transplantation was more prevalent among patients who migrated (6.0%)compared with those who did not (3.7%).
Migration for liver transplantation has been increasing over time.
Kwong et al state that patient migration is a natural, albeit unintended, consequence of regional variations in organ transplantation. Although the proportion of patients traveling for transplantation is modest, its existence and the advantages it provides indicate the inequality in access to this lifesaving procedure in the US.
The opportunity to migrate provides advantages to patients who have the necessary information, means, or support to pursue this option, whereas other patients remain subjected to longer waiting times, facing escalating morbidity and mortality while awaiting transplantation. The current geographic disparity in access to liver transplantation disproportionately affects minority patients and those in lower income areas or with public insurance—populations that are already at greater risk for poor outcomes and excess mortality.
Variations in likelihood of liver transplantation include differences in local donation and procurement rates, organ acceptance and utilization practices, local incidence of conditions requiring liver transplantation, and timely access to health care and liver transplantation.
The authors state that the geographic disparity is in part attributable to organ acceptance and use practices, because migrating patients were more likely to receive organs considered to be less desirable. This more permissive organ acceptance attitude might result from confidence at some of these centers of excellence in their ability to maintain robust outcomes even with higher-risk organs.
Kwong et al point out that there are several states without a transplant center, whose residents must travel across state lines to reach the nearest transplant center. Other patients may travel to centers with programs for certain diagnoses, such as hilar cholangiocarcinoma or rare metabolic conditions, or to centers with a specific expertise, including living donor liver transplantation. Furthermore, certain insurers, similar to the VA system, arrange their patients to travel outside their local area for liver transplantation to select centers where their patients are expected to have a better outcome.
Nonetheless, the phenomenon of migration for liver transplantation reveals the geographic differences in organ access in the US. Although inequity in access to life-saving health care interventions based on socioeconomic factors is not unique to liver transplantation, it is accentuated by geographic disparities in organ transplantation. Kwong et al conclude that as we search for strategies for better-informed liver transplant allocation policies and optimized organ-use practices, patient migration and its hidden costs should be considered.