麻豆传媒

Transplant teams showed consistent patterns of denying donor hearts to certain patients after offers became available, based on data from the United Network for Organ Sharing (UNOS).

The cumulative probability of a donor heart being accepted by the transplant center team was most favorable for white women, followed by Black women, white men, then Black men, according to a research group led by Khadijah Breathett, MD, MS, of Indiana University in Indianapolis.

This was supported by both the proportions of first offers accepted (white women 17.5%, Black women 14.0%, white men 10.3%, Black men 7.9%) and the median number of offers until an offer was accepted (five for white women, seven for Black women, nine for white men, and 11 for Black men).

"These disparities persisted after adjusting for candidate-, donor-, and offer-level variables, possibly suggesting racial and gender bias in the decision-making process," the investigators .

Overall, the investigators reported an accepted offer for 72.5% of transplant candidates. It took a median six offers to get to an accepted offer (range from 1 to 243).

They found worse odds of acceptance for Black candidates than for white candidates for the first offer (OR 0.76, 95% CI 0.69-0.84) through the 16th offer. Odds of acceptance were higher for women than for men for the first offer (OR 1.53, 95% CI 1.39-1.68) through the sixth offer and were lower for the 10th through 31st offers.

"These issues could be generated from a false security that Black patients and/or men can wait longer for a better offer or from greater fear of a bad outcome with selecting an 'imperfect' donor for a particular race and/or gender," Breathett's group surmised.

Much attention has been paid to the fair distribution of coveted donor hearts, the demand for which far exceeds supply.

UNOS and the Organ Procurement and Transplantation Network have acknowledged the shortcomings of the current six-tier system -- allowing some to game the system with overtreatment and exception requests, for example -- and the two organizations are preparing to move donor heart allocation to continuous distribution in which patients are scored mainly by medical urgency.

Yet in the new study, Breathett's group also highlights the importance of transplant centers and their cardiothoracic surgeons and heart transplant cardiologists. They make the ultimate decisions to accept or deny donor heart offers for patients with end-stage heart failure.

"Changes in the decision pathway to accept a donor organ are needed," the study authors emphasized.

"While the registry data used in these analyses have been crucial for exposing disparities, it is time to fund more detailed analyses of these practices, including in-depth studies of social determinants of health and race-based differences in immune responses in the setting of organ transplantation," said Paul Heidenreich, MD, MS, and two colleagues of Stanford University School of Medicine in California in an .

"What may be surprising to many is that most organ offers are refused by the transplant teams, and 44% of offered organs are never transplanted despite multiple offers," Heidenreich noted.

He said that 67% of refusals are attributed to poor-quality organs, the rest being judged a poor match for the patient or no longer suitable due to a change in the person's clinical status.

Breathett's team performed a cohort study relying on UNOS datasets for information about adults listed for heart transplant from October 2018 (when the current UNOS policy was implemented) to March 2023.

For 14,890 candidates listed for heart transplant, there were 159,177 heart offers with 13,760 donors. For each given candidate, all offers were tallied up to the first accepted offer in the present analysis.

By race, 30.9% of candidates were Black, 69.1% were white, 73.6% were men, and 26.4% were women.

The most common initial waiting list status was 4 out of 1-6 (over 36% of individuals). White men had the highest proportion of prior non-ventricular assist device cardiac surgeries (43.7%), and Black men had the highest proportion of left ventricular assist devices at listing (32.4%).

The investigators cautioned that they could not adjust for certain donor characteristics and the donor filters set by transplant centers for each candidate.

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