Gender differences in liver donor quality are predictive of graft loss.

Some studies have found that donor-recipient gender mismatch predicts posttransplant outcomes but whether this is independent of donor quality is unknown. To evaluate the association between gender mismatch and graft loss, 11 508 females (F) and 16 714 males (M) who underwent liver transplant from March 1, 2002 to December 31, 2007 were studied. Of 11 donor characteristics, clinically relevant differences between F and M donors were median age (47 vs. 39 years), height (165 vs. 178 cm) and proportion dying of stroke (59 vs. 35%) (p < 0.001 for all). The donor risk index was significantly lower for F than M donors (1.3 vs. 1.6, p < 0.001). Recipients of gender-mismatched grafts had an 11% higher risk of graft loss (p < 0.001). Compared to M→M donor-recipient-matched transplants in univariable analysis, F→M mismatch was associated with a 17% increased risk of graft loss (95% CI = 1.11-1.24, p < 0.001), whereas M→F mismatch was not (HR = 1.02; 95% CI = 0.96-1.09; p = 0.46). However, adjustment for significant recipient and donor factors eliminated the association between F→M mismatch and graft loss (HR = 0.95; 95% CI = 0.89-1.02; p = 0.18). In conclusion, donor quality differs significantly between female and male donors-female donors are older, shorter and die more frequently of stroke-and gender differences in donor quality, rather than gender mismatch are predictive of graft loss.