S. E. Rudasill1, Y. Sanaiha1, H. Xing1, A. Mardock1, H. Khoury1, P. Benharash1 1David Geffen School Of Medicine, University Of California At Los Angeles,Cardiac Surgery,Los Angeles, CA, USA
Introduction:
Listing criteria for lung transplantation influence demand for transplant. Occasionally, listed candidates clinically improve and are delisted, but their outcomes have not been elucidated. This study examined a national database for the characteristics and survival of primary and re-transplant lung transplant candidates who improved to delisting.
Methods:
This was a retrospective study of patients listed for lung transplantation between 1987-2015 in the United Network for Organ Sharing (UNOS) database. The last permanent waiting list status change was classified into transplanted, improved to delisting, or deteriorated to delisting, with those dying before or refusing transplant excluded from analysis. Survival time was calculated using the linked Social Security Administration date of death, and analysis was performed via the Kaplan-Meier method. Adjusted Cox hazards models predicted five-year mortality, while multivariable logistic regression identified the patient characteristics predicting improvement to delisting. Transplant centers were organized into quartiles by volume and analyzed for differences in the proportion of candidates improving or deteriorating.
Results:
Of 13,688 candidates, 12,188 (89.0%) were transplanted, 1,046 (7.6%) deteriorated to delisting, and 454 (3.3%) improved to delisting. Patients who improved were younger (48.5 vs. 50.9 years, p<0.001), less likely male (39.1 vs. 54.6%, p<0.001), and more likely to use life support measures at listing (7.3 vs. 2.9%, p<0.001) relative to those transplanted. Cox regressions showed increased five-year mortality for improved (HR=1.21 [1.07-1.38], p=0.002) and deteriorated (HR=3.36 [3.11-3.64], p<0.001) candidates relative to those transplanted, but two-year survival was highest in improved candidates (Figure 1). The short-term survival benefit for those improving was observed in primary (log rank p<0.001) but not re-transplant (log rank p=0.767) candidates. Those most likely to improve to delisting were older than 60 years (OR=1.96 [1.26-3.05], p=0.003), listed for primary pulmonary hypertension (OR=2.27 [1.13-4.56], p=0.022), and used life support measures at listing (OR=3.63 [2.15-6.13], p<0.001) relative to those transplanted. The percentage of candidates improving to delisting increased with increasing hospital volume (p<0.001).
Conclusion:
Primary lung transplant candidates improving to delisting faced lower short-term but higher five-year mortality relative to transplanted candidates. This effect did not persist for re-transplantation. Institutional volume may influence variations in listing practices. Understanding the characteristics and outcomes of this delisted population can better inform future candidate selection criteria.
