title: Impact of forced vital capacity loss on survival after the onset of chronic lung allograft dysfunction.
abstract: BACKGROUND
  Emerging evidence suggests a restrictive phenotype of chronic lung allograft dysfunction (CLAD) exists; however, the optimal approach to its diagnosis and clinical significance is uncertain.
  
  
  OBJECTIVE
  To evaluate the hypothesis that spirometric indices more suggestive of a restrictive ventilatory defect, such as loss of FVC, identify patients with distinct clinical, radiographic, and pathologic features, including worse survival.
  
  
  METHODS
  Retrospective, single-center analysis of 566 consecutive first bilateral lung recipients transplanted over a 12-year period. A total of 216 patients developed CLAD during follow-up. CLAD was categorized at its onset into discrete physiologic groups based on spirometric criteria. Imaging and histologic studies were reviewed when available. Survival after CLAD diagnosis was assessed using Kaplan-Meier and Cox proportional hazards models.
  
  
  RESULTS
  Among patients with CLAD, 30% demonstrated an FVC decrement at its onset. These patients were more likely to be female, have radiographic alveolar or interstitial changes, and histologic findings of interstitial fibrosis. Patients with FVC decline at CLAD onset had significantly worse survival after CLAD when compared with those with preserved FVC (P < 0.0001; 3-yr survival estimates 9% vs. 48%, respectively). The deleterious impact of CLAD accompanied by FVC loss on post-CLAD survival persisted in a multivariable model including baseline demographic and clinical factors (P < 0.0001; adjusted hazard ratio, 2.73; 95% confidence interval, 1.86-4.04).
  
  
  CONCLUSIONS
  At CLAD onset, a subset of patients demonstrating physiology more suggestive of restriction experience worse clinical outcomes. Further study of the biologic mechanisms underlying CLAD phenotypes is critical to improving long-term survival after lung transplantation.
authors: 1 Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine.
authors: Jamie L
authors: JL
authors: Todd
authors: Rahil
authors: R
authors: Jain
authors: Elizabeth N
authors: EN
authors: Pavlisko
authors: C Ashley
authors: CA
authors: Finlen Copeland
authors: John M
authors: JM
authors: Reynolds
authors: Laurie D
authors: LD
authors: Snyder
authors: Scott M
authors: SM
authors: Palmer
mesh_terms: D000328:Adult; D001989:Bronchiolitis Obliterans / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology*; D002908:Chronic Disease; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D016040:Lung Transplantation / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010641:Phenotype; D055031:Primary Graft Dysfunction / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology*; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D013147:Spirometry; D016019:Survival Analysis; D014797:Vital Capacity