Geographic Disparities in Liver-Related Mortality Suggest Inequitable Access to Liver Transplant

Michael Charlton, MBBS

Credit: GI Research Foundation

New research is calling attention to a notable increase in liver-related mortality since the COVID-19 pandemic, highlighting geographic disparities in access to liver transplantation hindering equitable access to the life-saving procedure.¹

Study findings showed that regardless of waitlist rates, there was a > 4-fold variation in liver-related mortality between states. Of note, compared with states with the lowest liver-related mortality, those with the highest liver-related mortality had lower transplant rates, likely reflecting a relative lack of access to liver transplants.¹

“Although sequential refinements of organ allocation policy have enhanced some measures of equity, including waiting list mortality and transplant rates among patients with high MELD scores on the waiting list, these metrics do not capture liver-related mortality, regional variation in liver-related mortality, or regional access to liver transplant,” Michael Charlton, MBBS, a professor of medicine, director of the center for liver diseases, and co-director of the transplant institute at the University of Chicago School of Medicine, and colleagues wrote.¹ “Ideally, a liver transplant would be equally available to all patients who might benefit from it, with the distribution of transplant centers and liver transplant procedures broadly reflecting the burden of liver-related mortality. Outcomes data associating liver transplant rates and donor organ use with geographic variance in liver-related mortality, however, remain sparse.”

To assess temporal trends and geographic variance in liver-related mortality and liver transplant in the US, investigators examined the frequencies of organ transplant by state with respect to liver-related mortality based on data from the Scientific Registry of Transplant Recipients (SRTR) and Centers for Disease Control and Prevention (CDC) Wide Ranging Online Data for Epidemiologic Research (WONDER) databases for the years 2018 and 2021.¹

The frequencies of livers exported as a proportion of all-source donor use (donor organ transplant for a state recipient from in-state and out-of-state sources) were obtained from the SRTR database. Additionally, the number of livers donated and transplanted according to the state of residence of each donor and recipient was obtained from the United Network for Organ Sharing. Investigators divided states into quintiles by either the frequency of imported or exported livers or liver-related mortality, which was captured by ICD-10 codes for all acute and chronic liver-related mortality.¹

Overall liver-related mortality in the US was 93,418 in 2021, with a crude rate of 28.1 per 100,000 individuals. Of note, this represents a 19.1% increase from the rate seen prior to the COVID-19 pandemic in 2018 (77,282; 23.6 per 100,000 individuals).¹

Investigators called attention to significant variations in liver-related mortality in 2021 by state, ranging from 18.4 per 100,000 individuals per year in Utah to 65.9 per 100,000 individuals per year in New Mexico. They noted states with the highest liver-related mortality had a lower rate of in-state donor transplantation than states in the lowest liver-related mortality quintile (13.0% vs 35.2% in-state donors; 95% CI, 14.1%-30.3%; SE, 3.9%; P <.001).¹

Additionally, states with the greatest proportion of liver transplants from in-state donors had a significantly lower mean liver-related mortality than states with the lowest mean proportion of transplants from in-state donors (95% CI, 0.5-13.4; SE, 3.1; P = .03). Of note, 10 states had no liver transplant center, and 60% of states with the highest rates of liver-related mortality do not have liver transplant centers.¹

Investigators also observed a notable disparity in the frequency of donor livers transplanted into residents of states other than where the donor resided. Residents of states in the lowest liver-related mortality quintile received > 2 times more livers than residents from these states donated, while states in the highest liver-related mortality quintile exported 6% more livers than citizens from these states received at any location (95% CI, 0.7%-1.4%; P <.001).¹

States with greater liver-related mortality rates transplanted fewer livers donated in-state and had a significantly higher number of deaths per transplant. Specifically, the median number of deaths per transplant from livers donated in-state was 26.8 (interquartile range [IQR], 20.5-38.6) in the lowest liver-related mortality quintile compared with a median of 109.9 (IQR, 52.1-155) in the highest quintile (95% CI, 26.1-133.2; P <.001).¹

The mean number of liver-related deaths per transplant from all donor sources ranged from 7.2 in the lowest liver-related mortality quintile to 21.5 in the highest (95% CI, 12.1-16.6; SE, 1.1; P <.001). In addition, investigators noted residents of states within the highest quintile of liver-related deaths per transplant from in-state donors received fewer in-state donor livers for transplants, using a mean of 5.4% of livers donated within their borders compared with 52.1% in states in the lowest quintile (95% CI, 34.3%- 59.1%; SE, 5.9%; P < .001). Residents of states in the highest quintile of deaths per transplant from all sources transplanted a mean of 9.8% of livers donated in-state compared with 32.1% in the lowest quintile (95% CI, 10.6%-34.2%; SE, 5.6%; P <.001).¹

Investigators acknowledged the variance in perceived and actual cause of death as recorded on death certificates, the source documents for the causes of death in the CDC WONDER database, as a limitation to these findings. They also pointed out the potential for information and confounding biases.¹

“The study by Rinella et al adds to the growing body of evidence that there is more to the geographic disparities appreciated among patients with liver disease that necessitates liver transplantation,” Ashley Spann, MD, an assistant professor in the division of gastroenterology, hepatology, and nutrition and an assistant professor of biomedical informatics at Vanderbilt University Medical Center, and colleagues wrote in an invited commentary.² “Despite trying to mitigate boundaries with acuity circle implementation, the state line boundary represents a barrier that may warrant national health policy intervention to improve equitable access and begs the question, when will we see an end to the amalgam of disparities in access to and receipt of liver transplant?”

References

1. ^{Rinella NS, Charlton W, Reddy G, et al. Current Burden of and Geographic Disparities in Liver Mortality and Access to Liver Transplant. JAMA Netw Open. doi:10.1001/jamanetworkopen.2024.39846}
2. ^{Spann A, Lopez C, Izzy M. Disparities in Outcomes of Liver-Related Waiting List for Transplant—Is There an End in Sight? JAMA Netw Open. doi:10.1001/jamanetworkopen.2024.39836}