High Lung Allocation Score Is Associated With Increased Morbidity and Mortality Following Transplantation

doi:10.1378/chest.09-0319

Chest

Volume 137, Issue 3, March 2010, Pages 651-657

https://doi.org/10.1378/chest.09-0319 Get rights and content

Background

The lung allocation score (LAS) was initiated in May 2005 to allocate lungs based on medical urgency and posttransplant survival. The purpose of this study was to determine if there is an association between an elevated LAS at the time of transplantation and increased postoperative morbidity and mortality.

Methods

The United Network for Organ Sharing provided de-identified patient-level data. Analysis included lung transplant recipients aged ≥ 12 years who received transplants between April 5, 2006, and December 31, 2007 (n = 3,836). Recipients were stratified into three groups: LAS < 50 (n = 3,161, 83.87%), LAS 50 to 75 (n = 411, 10.9%), and LAS ≥ 75 (n = 197, 5.23%), referred to as low LAS (LLAS), intermediate LAS (ILAS), and high LAS (HLAS), respectively. The primary outcome was posttransplant graft survival at 1 year. Secondary outcomes included length of stay and in-hospital complications.

Results

HLAS recipients had significantly worse actuarial survival at 90 days and 1 year compared with LLAS recipients. When transplant recipients were stratified by disease etiology, a trend of decreased survival with elevated LAS was observed across all major causes of lung transplant. HLAS recipients were more likely to require dialysis or to have infections compared with LLAS recipients (P < .001). In addition, length of stay was higher in the HLAS group when compared with the LLAS group (P < .001).

Conclusions

HLAS is associated with decreased survival and increased complications during the transplant hospitalization. Whereas the LAS has improved organ allocation through decreased waiting list deaths and waiting list times, lower survival and higher morbidity among HLAS recipients suggests that continued review of LAS scoring is needed to ensure optimal long-term transplant survival.

Section snippets

Data Collection

Use of data in this analysis is consistent with the regulations of our university's institutional review board and the UNOS Data Use Agreement. The Standard Transplant Analysis and Research Dataset was provided by UNOS (data source No. 022009-3). The dataset contains information collected from the UNetsm database forms, including the Transplant Candidate Registration form, the Transplant Recipient Registration form, and the Transplant Recipient Follow-up form. These data are the basis for the

Results

A total of 3,769 lung transplant recipients were included in the analysis. LAS scores were distributed as follows: LLAS (n = 3,161, 83.87%), ILAS (n = 411, 10.9%), and HLAS (n = 197, 5.23%). Mean follow-up time was 1.54 ± 0.90 (0-3.49) years. The distribution of LAS was right skewed (Fig 1), with a mean LAS of 42.1 ± 13.4 (range = 27.7-94.2). Baseline donor and recipient characteristics are shown in Table 1. There was no significant difference in baseline donor age, recipient age, peripheral

Discussion

Despite advances in the medical and surgical management of advanced lung disease, lung transplantation remains an integral treatment of patients suffering from end-stage pulmonary disease.¹¹ With the demand for lung transplantation continuing to outpace the supply of available organs, the LAS was developed to distribute organs in a manner that balances the degree of medical urgency with the probability of posttransplant survival. In this analysis, we use UNOS data to examine nearly 4,000

Conclusions and Implications

An increased LAS was associated with decreased survival following lung transplantation. In addition, an increased LAS was associated with increased length of stay following transplantation and higher rates of infection, renal failure, and stroke. Although statistically significant differences were observed only among recipients who had COPD and IPF, a stepwise trend toward worsening survival with increasing LAS was observed across all etiologies of disease. Given these findings in the setting

Acknowledgments

Author contributions: Dr Russo: had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis, participated in the study concept and design, acquired data, analyzed and interpreted data, drafted the manuscript, critically revised the manuscript for important intellectual content, and analyzed statistics.

Dr Iribarne: had full access to all of the data in the study and takes responsibility for the integrity of the data

References (0)

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Funding/Support: This work was supported in part by Health Resources and Services Administration [contract 231-00-0115] and National Institutes of Health Training [Grant 5T32HL007854-13].

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (www.chestpubs.org/site/misc/reprints.xhtml).

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Original ResearchLung TransplantationHigh Lung Allocation Score Is Associated With Increased Morbidity and Mortality Following Transplantation

Background

Methods

Results

Conclusions

Section snippets

Data Collection

Results

Discussion

Conclusions and Implications

Acknowledgments

Original Research
Lung Transplantation
High Lung Allocation Score Is Associated With Increased Morbidity and Mortality Following Transplantation