Heart Transplantation in Brazil: Two Decades of Gender Disparities in the World's Largest Public Organ Transplant System.

BACKGROUND

Donor shortages pose challenges for heart transplantation (HT). Brazil has the largest public organ transplant system in the world, with notable sex disparities between donors and recipients. This study evaluates sex-specific differences in HT profiles and outcomes in a high-volume Brazilian program.

METHODS

We conducted two retrospective cohort studies: adult HT recipients between October 1997 and March 2023, and donors offered to the same center from January 2013 to March 2023. Survival was assessed via Kaplan-Meier, with 95% confidence intervals.

RESULTS

Among 426 recipients, 80.7% were men (mean age: 48.4 ± 12.0 years vs 44.8 ± 11.1 for women, P = .014). Dilated cardiomyopathy was the leading cause of HF in both sexes (men: 35%, women: 28%), followed by ischemic heart disease (27%) in men and Chagas disease (15%) in women. Women had higher rates of hypertension compared to men (14.6% vs 6.7%, P = .03), whereas no significant differences were observed for diabetes or chronic kidney disease. Survival rates at 1, 5, and 10 years (73%, 62%, and 49%, respectively) showed no sex-based differences (hazard ratios 0.71, confidence intervals 95% 0.44-1.15, P = .16), with median survival of 9.6 years. Among the 458 potential heart donors reported during the study period, the utilization rate was 40% (185 orthotopic HTs), with a median wait time of 46.5 days. Male donors predominated (84%) and were younger than females (28.8 ± 9.4 vs 34.8 ± 12.8 years, P < .01). Trauma was the leading cause of death among male donors (62%), while stroke was predominant in females (56%). Female donors had higher rates of hypertension (20% vs 4.5%, P < .01), but no differences were observed for diabetes or pretransplant vasoactive support. Discarded organs were mostly due to infection (20%). There was no significant differences across donor-recipient sex matching groups.

CONCLUSION

Women remain underrepresented among HT recipients and demonstrate distinct comorbidities compared to men, though survival outcomes are similar. Male donors predominate, with notable differences in demographics and causes of death between sexes. No significant differences in survival according to recipient sex or donor-recipient sex matching were observed. However, the study was not powered to exclude modest differences, and further studies with more detailed clinical and immunological characterization are warranted.