Racial Disparities and Outcomes of Temporary Waitlist Inactivation among Heart Transplant Candidates.

S. Mallick¹, S. Bakhtiyar², S. Sakowitz³, S. Kim¹, N. Cho⁴, E. O. Cruz⁵, P. Benharash^6
1UCLA, Los Angeles, California ²University of California Los Angeles UCLA, Los Angeles, California ³UCLA David Geffen School of Medicine, Los Angeles, California ⁴David Geffen School of Medicine, Los Angeles, California ⁵Stanford, Los Angeles, California ⁶UCLA Division of Cardiac Surgery, Los Angeles, California

Purpose: Temporary inactivation while awaiting heart transplant (HT) occurs in ~20% of recipients and is linked with racial and socioeconomic disparities and worse survival (1,2). Yet, differences in waitlist outcomes among temporarily inactivated patients have not been studied. We sought to investigate factors and waitlist survival associated with temporary inactivation.

Methods: This was a retrospective analysis of the United Network for Organ Sharing database after the 2018 heart allocation policy change. All adult patients listed for single-organ heart transplants between October 2018 and March 2023 were included. Patients were stratified into two groups: Never Inactivated (NI), and Temporarily Inactivated (TI). Racial differences in the timing and reason of inactivation were analyzed in three patient groups: Black, White, and Hispanic. A competing risk regression analysis was conducted to study the impact of inactive status on waitlist outcomes. Competing outcomes in the models included waitlist mortality or clinical deterioration with subsequent removal from the waitlist, transplant, or recovery warranting removal from the wait list. Additionally, competing risk regression analyses were conducted to analyze the influence of racial differences in transitioning from an inactive to active state, and survival on the waitlist after reactivation.

Results: Of 15,612 patients listed for HT, 4,380 (28.1%) experienced inactivation. Within the TI group, 1,177 (26.9%) were Black, 428 (9.8%) were Hispanic, and 2,616 (59.7%) were White (Table 1). TI patients spent considerably longer times (368.2±5.6 vs 101.4±1.8 days, p< 0.001) on the waitlist as compared to NI. While Black patients entered an inactive stage later (Black:191.0±6.3, White:170.0±4.0, Hispanic:170.0±4.0 days, p=0.03), they remained inactive for a longer period (Black:129.4±6, White:111.2±3.3, Hispanic:116.5±8.5 days, p=0.01). The most common reason for inactivation across all strata was being “temporarily too sick for transplant”. Further, Black patients were more commonly inactivated due to insurance issues (Black:4.7%, White:2.7%, Hispanic:3.5%, p=0.01) and medical non-compliance (Black:8.4%, White:3.9%, Hispanic:4.1%, p=0.01), relative to others.

Competing risk regression analysis demonstrated increased likelihood of mortality or deterioration in inactivated patients (subhazard ratio [SHR]: 6.84; 95%CI 5.99-7.80, p< 0.001), decreased likelihood of transplant (SHR: 0.25, 95%CI 0.24-0.27, p< 0 .001), and equivalent likelihood of recovery (SHR: 1.23, 95%CI 0.98-1.54, p=0.08) for waitlisted patients after they were reactivated (Figure1). While Black patients were less likely to be reactivated (SHR: 0.87, 95%CI 0.77-0.98, p=0.03), no racial differences were noted in waitlist survival among Black (SHR: 1.17, 95%CI 0.87-1.59, p=0.30) and Hispanic TI (SHR: 0.99, 95%CI 0.71-1.40, p=0.90) patients.

Conclusion: TI patients experience greater likelihood of mortality on the waitlist and decreased likelihood of transplant after being reactivated. Additionally, Black patients spend more time on the waitlist and face lower reactivation rates, compared to others. Interventions to better manage and prioritize TI patients are necessary to improve waitlist outcomes.

Identify the source of the funding for this research project: No funding to report