Panel Reactive Antibody and Donor-Recipient Sex Differences Do Not Affect Long-Term Lung Transplant Outcomes

Abstract

PurposePatients with elevated panel reactive antibody (PRA) experience delayed transplant and higher waitlist mortality than minimally sensitized patients. If transplanted, the importance of elevated PRA observed with donor-recipient sex differences on long-term outcomes remain unknown.MethodsThe United Network for Organ Sharing database was reviewed for all adult patients who underwent isolated lung transplantation between 2005 and 2015. All patients without known BOS status on follow up were excluded. The date of first BOS diagnosis, if present, was used for analysis. All remaining patients were censored at time of last follow up in absence of BOS, graft dysfunction, or death. Baseline and post-transplant outcomes were reviewed using descriptive and Kaplan-Meier analyses.ResultsBetween 2005 and 2015, 15596 lung transplant recipients with known BOS status were included in analysis and divided into donor-recipient subgroups: male to male (M-M; n=6846, 44%), male to female (M-F: n=2581, 16%), female to male (F-M: n=2347, 15%), and female to female (F-F: n=3822, 25%) - Table 1. The time between listing and transplant was highest among M-F, 263 (95% CI [246-280]), and F-F, 275 days (95% CI [261-289]), subgroups. Female recipients also had higher pre-transplant PRA%, 13.7 (F-F) and 15.0 (M-F), compared to males (p < 0.001 between groups). Overall, there were no differences in freedom from BOS (p=0.282) or graft dysfunction (p=0.602) when adjusted for single or double transplant and donor-recipient subgroup. Composite survival differed between groups (p < 0.001 by log rank test); however, this was unaffected by subgroup PRA% when analyzed continuously or stratified by quartiles.ConclusionDonor-recipient sex differences are associated with elevated pre-transplant PRA levels in female recipients; however, pre-transplant PRA had no observed impact on graft and survival outcomes in all disease groups. The clinical significance of PRA after transplant selection, if any, remains unclear. Patients with elevated panel reactive antibody (PRA) experience delayed transplant and higher waitlist mortality than minimally sensitized patients. If transplanted, the importance of elevated PRA observed with donor-recipient sex differences on long-term outcomes remain unknown. The United Network for Organ Sharing database was reviewed for all adult patients who underwent isolated lung transplantation between 2005 and 2015. All patients without known BOS status on follow up were excluded. The date of first BOS diagnosis, if present, was used for analysis. All remaining patients were censored at time of last follow up in absence of BOS, graft dysfunction, or death. Baseline and post-transplant outcomes were reviewed using descriptive and Kaplan-Meier analyses. Between 2005 and 2015, 15596 lung transplant recipients with known BOS status were included in analysis and divided into donor-recipient subgroups: male to male (M-M; n=6846, 44%), male to female (M-F: n=2581, 16%), female to male (F-M: n=2347, 15%), and female to female (F-F: n=3822, 25%) - Table 1. The time between listing and transplant was highest among M-F, 263 (95% CI [246-280]), and F-F, 275 days (95% CI [261-289]), subgroups. Female recipients also had higher pre-transplant PRA%, 13.7 (F-F) and 15.0 (M-F), compared to males (p < 0.001 between groups). Overall, there were no differences in freedom from BOS (p=0.282) or graft dysfunction (p=0.602) when adjusted for single or double transplant and donor-recipient subgroup. Composite survival differed between groups (p < 0.001 by log rank test); however, this was unaffected by subgroup PRA% when analyzed continuously or stratified by quartiles. Donor-recipient sex differences are associated with elevated pre-transplant PRA levels in female recipients; however, pre-transplant PRA had no observed impact on graft and survival outcomes in all disease groups. The clinical significance of PRA after transplant selection, if any, remains unclear.