Sex differences in patient acceptance of cardiac transplant candidacy

The overwhelming majority of cardiac transplant recipients are men. This can be partially explained by the earlier age at which heart failure develops in men. However, an underrepresentation of women also may reflect physician referral or selection biases or differences in patients' access to or acceptance of heart transplantation.

We investigated whether sex bias occurred in the transplant candidate selection process at a single cardiac transplant center. We prospectively evaluated 386 individuals < 70 years of age (295 men, 91 women) referred for management of moderate to severe heart failure and/or cardiac transplant evaluation. Age, race, sex, heart failure type, New York Heart Association class, left ventricular ejection fraction, peak exercise oxygen consumption, disease duration, resting hemodynamic measurements, comorbidity index score, health insurance coverage, and estimated household income were recorded. For patients not accepted for transplantation, the reason for rejection was also obtained. Univariable and multivariable (logistic regression) analyses were performed comparing men and women and patients accepted and those not accepted for cardiac transplantation. Female sex was independently associated with rejection for cardiac transplantation (odds ratio, 2.57; P = .01). However, the reason for rejection (odds ratio, 2.57; P = .01). However, the reason for rejection was more likely to be patient self-refusal for women than for men (29% versus 9%), and female sex was independently associated with patient self-refusal (odds ratio, 4.68; P = .003). When patients who refused transplant were reclassified as accepted for transplant, female sex was no longer associated with nonacceptance. However, lower patient income was associated with nonacceptance for transplant.

We found no evidence of sex bias in the selection of cardiac transplant recipients at our center. These findings suggest that the underrepresentation of women among cardiac transplant recipients may result, in part, from a sex difference in treatment preference, with a decreased willingness of women to undergo transplantation. The reasons for the difference in acceptance rates between men and women need to be elucidated.