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Published on: June 23, 2014
Center-Level Variation in Transplant Rates Following the Heart Allocation Policy Change
Zachary Tran1,2, Roland Hernandez3, Josef Madrigal1
1Cardiovascular Outcomes Research Laboratories, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles.
Insights
Heart transplant rates varied significantly between US centers even after the 2018 policy change. This suggests persistent disparities in organ allocation despite policy updates, necessitating further research for equitable access to heart transplants.
Area of Science:
- Cardiology
- Transplant Surgery
- Health Policy
Background:
- State-level variations in heart transplant waiting list outcomes are documented.
- Little is known about center-level transplant rates post-heart allocation policy change.
Purpose of the Study:
- To evaluate center-level heart transplant rates following the 2018 allocation policy revision.
- To identify factors influencing transplant rates across different centers.
Main Methods:
- Nationwide cohort study using United Network for Organ Sharing data (Oct 2015 - Mar 2020).
- Analysis of two time cohorts: pre-policy change (Era 1) and post-policy change (Era 2).
- Competing risk regression used to calculate adjusted center-level transplant rates.
Main Results:
- The adjusted mean center-level likelihood of heart transplant increased from 48.1% (Era 1) to 78.0% (Era 2).
- Significant variation in transplant rates persisted across regions, states, and within organ procurement organizations.
- Centers with higher transplant volumes and greater use of intra-aortic balloon pumps showed higher transplant rates.
Conclusions:
- Intercenter disparities in heart transplant likelihood have persisted post-policy change.
- Geographical proximity and shared organ supply did not eliminate these disparities.
- Further research is needed to ensure equitable organ allocation in heart transplantation.
Importance:
Wide state-level variability in waiting list outcomes have been noted for patients listed for heart transplant in the US, but little is known regarding center-level transplant rates since the heart allocation policy change.
Objective:
To evaluate center-level transplant rates following the recent allocation policy change for heart transplant.
Design, Setting, And Participants:
This cohort study used data from the United Network for Organ Sharing database from October 18, 2015, to March 1, 2020, for a nationwide analysis of transplant centers in the US. Transplant candidates were stratified into 2 time cohorts, with era 1 denoting the 3-year period before the policy change (October 18, 2018), and era 2 representing the 500-day period after the policy change but before the beginning of the COVID-19 pandemic. Data were analyzed from May to June 2021.
Exposure:
The heart allocation policy change enacted on October 18, 2018.
Main Outcomes And Measures:
Competing risk regression for waiting list outcomes was performed to calculate adjusted era 1 and era 2 center-level transplant rates. Rates were compared across regions and states, as well as within organ procurement organizations. Pearson correlation coefficient was used to assess center-level factors associated with era 2 transplant rates.
Results:
Of 15 940 transplant candidates included for analysis, 5063 (median [IQR] age, 56 [45-63] years; 1385 women [27.4%]) comprised the era 2 cohort. The proportion of patients with temporary mechanical circulatory support increased between era 1 and era 2 (extracorporeal membrane oxygenation, 2.00% vs 3.42%; percutaneous ventricular assist device, 0.66% vs 1.86%; intra-aortic balloon pump, 5.21% vs 13.10%). The adjusted mean center-level likelihood of transplant increased after the rule change (from 48.1% in era 1 to 78.0% in era 2). Significant variation in transplant rates was observed across regions and states even among centers with shared organ procurement organizations. The largest absolute difference in transplant rates was 27.1% for 2 centers belonging to the same organ procurement organization. Centers with higher transplant volumes in era 2 and with a greater proportion of candidates with intra-aortic balloon pump were observed to have higher transplant rates.
Conclusions And Relevance:
Despite sharing organ supply and having a small geographical distance, these findings suggest that intercenter disparities in the likelihood of transplant have persisted following the heart allocation policy change. Further work is necessary to ensure equitable allocation of organs in heart transplant.
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