Impact of donor obesity on outcomes of donation after circulatory death heart transplantation.

BACKGROUND

In the setting of the obesity epidemic and donor organ shortage in the United States, there is a growing need to expand the donor organ eligibility criteria for orthotopic heart transplantation (OHT). Donation after circulatory death (DCD) has emerged as a promising solution, but the outcomes with obese donor hearts in DCD OHT remains unknown.

METHODS

Using the United Network for Organ Sharing registry between 2019 and 2024, recipients of DCD OHT were stratified into 3 donor obesity categories by body mass index (BMI): underweight/normal (BMI <25 kg/m), overweight (BMI 25-30 kg/m), and obese (BMI >30 kg/m). These cohorts were subgrouped by organ procurement strategy: direct procurement and preservation (DPP) or normothermic regional perfusion (NRP). Recipient and donor characteristics and risk factors for mortality were analyzed using Cox regression hazard models. Survival at 30 days, 1 year, and 5 years post-transplantation were analyzed using the Kaplan-Meier method.

RESULTS

We found no significant differences in patient and graft survival between donor BMI categories at all time points. Among recipients of overweight (hazard ratio [HR], 0.38; P = .0371) and obese (HR, 0.24; P = .0493) donor hearts, NRP was associated with decreased risk of mortality. Donor-recipient predicted heart mass (PHM) undermatching (defined as <86%) was associated with increased risk of mortality among underweight/normal weight donors (HR, 1.28; P = .0323) and overweight donors (HR, 1.08; P = .0382).

CONCLUSIONS

Donor obesity does not confer an increased risk of recipient mortality in DCD OHT, particularly when NRP is used. PHM undermatching continues to be associated with adverse outcomes in DCD OHT.