Lung Transplant Outcomes in Patients Hospitalized with Stable or Acute Exacerbations of Interstitial Lung Disease

Abstract

Acute exacerbations of interstitial lung disease (AE-ILD) have a poor prognosis, and lung transplantation can be lifesaving. Previous studies have reported significantly higher mortality in patients transplanted with acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) compared to stable IPF. These results have yet to be corroborated, and whether they apply to the wide spectrum of AE-ILD beyond IPF is unknown. This study aimed to compare outcomes between transplanted AE-ILD patients, non-transplanted AE-ILD patients, and stable ILD patients hospitalized to undergo lung transplantation. This was a retrospective review of adults hospitalized with AE-ILD and stable patients hospitalized for elective lung transplantation due to end-stage ILD between January 2014 and February 2019. An acute exacerbation was defined using the revised definition and diagnostic criteria for AE-IPF. The primary outcome was post-hospitalization survival. For hospitalized transplanted patients, secondary outcomes included hospital length of stay post-transplant, grade of primary graft dysfunction, graft rejection, re-hospitalization, and cause of death. Twenty-nine patients were stable and electively admitted for lung transplantation, and 53 were hospitalized with AE-ILD, of whom 23 received a lung transplant and 28 did not. The average lung allocation score at the time of transplant for stable ILD patients was 41.79 compared to 81.61 for patients with AE-ILD (p<0.0001). Average follow-up was 17±10 months. Every lung transplant recipient survived, whereas only 8 of 28 (28%) non-transplanted patients with ILD exacerbations survived to hospital discharge. Secondary outcomes were not statistically significantly different between AE-ILD and stable ILD lung transplant recipients. Mortality rates were significantly higher in patients with AE-ILD who were not transplanted, but survival and post-hospitalization outcomes were comparable in patients transplanted with AE-ILD versus stable ILD. These results highlight the important role played by lung transplantation in eligible patients admitted with AE-ILD.