Mitigating the Impact of Gender Mismatch in Heart Transplantation Using BMI and BSA Ratios

Abstract

Purpose Heart transplantation is limited by the supply of donor organs. Previous studies have associated donor/recipient gender mismatch with decreased post-transplant survival and increased rates of primary graft dysfunction. We evaluate whether this risk can be mitigated. Methods We performed a retrospective analysis of the OPTN/UNOS registry encompassing years 1987 to 2018 for all male adult recipients (>18 years) who underwent isolated heart transplantation with grafts from female donors. Comparison was made to transplants from male donors. Recipients were primarily stratified into two groups, those with BMI less than or greater than donor BMI. Patients were stratified by BSA on secondary analysis. Kaplan-Meier analysis was used to estimate survival post-transplant. Cox Proportional Hazards modeling was performed to identify independent predictors of survival. Results A total of 8,232 candidates met inclusion criteria. Male recipients receiving hearts from higher BMI female donors were more likely to be in the ICU pre-transplant (39.5% vs 36.6%, p = 0.001), on IV inotropes at listing (35.7% vs 33.0%, p = 0.013), and were less likely to have a history of diabetes (21.4% vs 23.9%, p = 0.012). On Kaplan-Meier analysis, recipients transplanted with hearts from higher BMI female donors had improved overall survival. When stratified by BSA (Figure 1), male recipients transplanted with hearts from higher BSA female donors had similar post-transplant survival as male recipients who received hearts from male donors. On Cox Proportional Hazards analysis, increased donor BMI/BSA relative to recipient BMI/BSA remained an independent predictor of improved survival (p < 0.05). Conclusion Prior studies have associated transplanting hearts from female donors into male recipients with decreased post-transplant survival. In this study we have demonstrated that this may be mitigated by matching grafts from female donors to male recipients with lower BMI and especially BSA. Heart transplantation is limited by the supply of donor organs. Previous studies have associated donor/recipient gender mismatch with decreased post-transplant survival and increased rates of primary graft dysfunction. We evaluate whether this risk can be mitigated. We performed a retrospective analysis of the OPTN/UNOS registry encompassing years 1987 to 2018 for all male adult recipients (>18 years) who underwent isolated heart transplantation with grafts from female donors. Comparison was made to transplants from male donors. Recipients were primarily stratified into two groups, those with BMI less than or greater than donor BMI. Patients were stratified by BSA on secondary analysis. Kaplan-Meier analysis was used to estimate survival post-transplant. Cox Proportional Hazards modeling was performed to identify independent predictors of survival. A total of 8,232 candidates met inclusion criteria. Male recipients receiving hearts from higher BMI female donors were more likely to be in the ICU pre-transplant (39.5% vs 36.6%, p = 0.001), on IV inotropes at listing (35.7% vs 33.0%, p = 0.013), and were less likely to have a history of diabetes (21.4% vs 23.9%, p = 0.012). On Kaplan-Meier analysis, recipients transplanted with hearts from higher BMI female donors had improved overall survival. When stratified by BSA (Figure 1), male recipients transplanted with hearts from higher BSA female donors had similar post-transplant survival as male recipients who received hearts from male donors. On Cox Proportional Hazards analysis, increased donor BMI/BSA relative to recipient BMI/BSA remained an independent predictor of improved survival (p < 0.05). Prior studies have associated transplanting hearts from female donors into male recipients with decreased post-transplant survival. In this study we have demonstrated that this may be mitigated by matching grafts from female donors to male recipients with lower BMI and especially BSA.