Height Difference in Donor-Recipient Sex Mismatch is Significant in Single Lung Transplant Patients with Chronic Obstructive Pulmonary Disease

Abstract

<h3>Purpose</h3> Lung-size matching has been considered a critical factor with few studies evaluating height in association with gender matching based on the etiology of lung failure. This study investigated the role of height and gender matching in donor selection with regards to laterality in single lung transplants for chronic obstructive pulmonary disease (COPD). <h3>Methods</h3> A retrospective review of the United Organ Sharing Network (UNOS) database was performed on adult single lung transplants for COPD from 2010 to 2020. Pts with prior transplants were excluded. Difference in donor and recipient height were categorized in ± 10 cm intervals. Donor and recipient sex status were matched and stratified. Baseline characteristics and time to onset of BOS were reviewed. Categorical and continuous variables were described with Chi square and one-way ANOVA respectively, and used as predictors for a multivariate Cox regression model of BOS. <h3>Results</h3> 1233 transplanted pts with pre-transplant diagnosis of COPD were included. Demographics such as age, sex, and height stratification for the cohorts are described in Table 1. In a multivariate model of freedom from BOS, left lung transplants (LLT) with slightly oversized lungs (5-15 cm difference) demonstrated a protective effect when adjusted for height difference (Hazard ratio 0.76, CI 0.58, 0.99, p=0.04). Donor matching displayed negative effect when there was MD-FR (Hazard ratio 1.43, p=0.02, CI 1.02, 1.07), and a protective effect for FD-FR (Hazard ratio 0.71, p=0.035, CI 0.51, 0.98). In contrast, there was no difference for freedom to BOS for height difference or with differences in sex between donor and recipients and time to BOS for right lung recipients (p=0.90). <h3>Conclusion</h3> Single lung transplants offer the ability to maximize resources due to the shortage in organ supply versus demand. A combination of gender and size mismatch must be carefully considered, particularly in oversized lungs and male to female recipients.