Use of Population-based Data to Demonstrate How Waitlist-based Metrics Overestimate Geographic Disparities in Access...

Liver allocation policies are evaluated by how they impact waitlisted patients, without considering broader outcomes for all patients with end-stage liver disease (ESLD) not on the waitlist. We conducted a retrospective cohort study using two nationally representative databases: HealthCore (2006-2014) and five-state Medicaid (California, Florida, New York, Ohio and Pennsylvania; 2002-2009). United Network for Organ Sharing (UNOS) linkages enabled ascertainment of waitlist- and transplant-related outcomes. We included patients aged 18-75 with ESLD (decompensated cirrhosis or hepatocellular carcinoma) using validated International Classification of Diseases, Ninth Revision (ICD-9)-based algorithms. Among 16 824 ESLD HealthCore patients, 3-year incidences of waitlisting and transplantation were 15.8% (95% confidence interval [CI] : 15.0-16.6%) and 8.1% (7.5-8.8%), respectively. Among 67 706 ESLD Medicaid patients, 3-year incidences of waitlisting and transplantation were 10.0% (9.7-10.4%) and 6.7% (6.5-7.0%), respectively. In HealthCore, the absolute ranges in states' waitlist mortality and transplant rates were larger than corresponding ranges among all ESLD patients (waitlist mortality: 13.6-38.5%, ESLD 3-year mortality: 48.9-62.0%; waitlist transplant rates: 36.3-72.7%, ESLD transplant rates: 4.8-13.4%). States' waitlist mortality and ESLD population mortality were not positively correlated: ρ = -0.06, p-value = 0.83 (HealthCore); ρ = -0.87, p-value = 0.05 (Medicaid). Waitlist and ESLD transplant rates were weakly positively correlated in Medicaid (ρ = 0.36, p-value = 0.55) but were positively correlated in HealthCore (ρ = 0.73, p-value = 0.001). Compared to population-based metrics, waitlist-based metrics overestimate geographic disparities in access to liver transplantation.