Influence of donor and recipient sex mismatch on heart transplant outcomes: analysis of the International Society for Heart and Lung Transplantation Registry.

BACKGROUND

Prior studies have presented contradictory results after analyzing associations between donor and recipient sex on survival after heart transplantation and causes of death such as acute rejection (AR) and cardiac allograft vasculopathy (CAV). We used the International Society for Heart and Lung Transplantation (ISHLT) Registry, the largest repository of heart transplant outcomes worldwide, to comprehensively address these questions.

METHOD

We studied 60,584 adult recipients of heart transplants performed between 1990 and 2008. Outcomes of interest were overall survival, death-censored allograft survival, AR, and CAV, which were studied using regression models. To assess whether donor/recipient sex mismatch affected outcomes, the experience of male recipients with female vs male donors was compared with that of female recipients with female vs male donors through inclusion of an interaction term between donor and recipient sex.

RESULTS

Significant differences were observed between male and female recipients in overall survival and death-censored allograft survival for female vs male donors. Male recipients of female allografts had a 10% increase in adjusted mortality relative to male recipients of male allografts, whereas female recipients of female allografts had a 10% decrease in adjusted mortality relative to female recipients of male allografts (p < 0.0001). Findings were similar for death-censored allograft survival. Differences in the effect of donor sex on AR or CAV between male and female recipients were not significant.

CONCLUSIONS

Analysis of the ISHLT data set has demonstrated a strong association between donor/recipient sex mismatch and reduced survival after heart transplantation.