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Five-Year Mortality Hazard Is Reduced In Chronic Obstructive Pulmonary Disease Patients Receiving Double- versus
Todd C Crawford1, Cecillia Lui1, J Trent Magruder1
1Division of Thoracic Surgery, Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Background:
Previous studies suggest double-lung transplant (DLT) may be associated with superior survival compared to single-lung transplantation (SLT) in chronic obstructive pulmonary disease (COPD) recipients. The purpose of this study was to compare survival in patients with COPD undergoing DLT versus SLT since the inception of the lung allocation score.
Methods:
We used the United Network for Organ Sharing database to retrospectively identify adult patients with COPD who underwent isolated lung transplantation from 5/4/2005-12/31/2014. We then separated patients into DLT versus SLT. Short-term (1 y) and long-term survival (5 y) were compared between DLT and SLT cohorts by the method of Kaplan-Meier, and Cox proportional hazards modeling was used to adjust for case mix.
Results:
Four thousand eight hundred thirty-two COPD patients were listed, and 3554 underwent lung transplantation over the study period, including 1358 SLTs (38%) and 2196 DLTs (62%). Survival 1 y after listing was 93% for those remaining wait listed (n = 1892) versus 91% for SLT (n = 1093) versus 89% for DLT (n = 1847) (log-rank P < 0.01). Survival at 1 y after transplant was 88% for both SLT and DLT groups (log-rank P = 0.93); however, 5-y survival was significantly lower after SLT (51% versus 59%, log-rank P < 0.01). After risk adjustment, hazard for 1-y mortality after DLT was not significantly reduced compared to SLT (hazard ratio 0.89 [0.69-1.14], P = 0.36) but was significantly reduced 5 y after DLT (hazard ratio 0.88 [0.78-0.99], P = 0.04).
Conclusions:
In the largest survival analysis of COPD recipients since the inception of the lung allocation score, the hazard for 5-y mortality was significantly reduced in recipients who underwent DLT as compared to SLT.
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