title: Myositis-associated usual interstitial pneumonia has a better survival than idiopathic pulmonary fibrosis.
abstract: To compare the survival outcomes between myositis-associated usual interstitial pneumonia (MA-UIP) and idiopathic pulmonary fibrosis (IPF-UIP).
  
  
  
  Adult MA-UIP and IPF-UIP patients were identified using CTD and IPF registries. The MA-UIP cohort included myositis or anti-synthetase syndrome patients with interstitial lung disease while manifesting UIP on high-resolution CT chest and/or a lung biopsy revealing UIP histology. IPF subjects met American Thoracic Society criteria and similarly had UIP histopathology. Kaplan-Meier survival curves compared cumulative and pulmonary event-free survival (event = transplant or death) between (i) all MA-UIP and IPF-UIP subjects, (ii) MA-UIP with biopsy proven UIP (n = 25) vs IPF-UIP subjects matched for age, gender and baseline forced vital capacity (±10%). Cox proportional hazards ratios compared the survival controlling for co-variates.
  
  
  
  Eighty-one IPF-UIP and 43 MA-UIP subjects were identified. The median cumulative and event-free survival time in IPF vs MA-UIP was 5.25/1.8 years vs 16.2/10.8 years, respectively. Cumulative and event-free survival was significantly worse in IPF-UIP vs MA-UIP [hazards ratio of IPF-UIP was 2.9 (95% CI: 1.5, 5.6) and 5.0 (95% CI: 2.8, 8.7) (P < 0.001), respectively]. IPF-UIP event-free survival (but not cumulative) remained significantly worse than MA-UIP with a hazards ratio of 6.4 (95% CI: 3.0, 13.8) after controlling for age at interstitial lung disease diagnosis, gender, ethnicity and baseline forced vital capacity%. Respiratory failure was the most common cause of death in both groups. A sub-analysis of 25 biopsy-proven MA-UIP subjects showed similar results.
  
  
  
  MA-UIP patients demonstrated a significant survival advantage over a matched IPF cohort, suggesting that despite similar histological and radiographic findings at presentation, the prognosis of MA-UIP is superior to that of IPF-UIP.
authors.affiliation: Division of Rheumatology and Clinical Immunology, Department of Medicine.
authors.forename: Rohit
authors.initials: R
authors.lastname: Aggarwal
authors.affiliation: Division of Rheumatology and Clinical Immunology, Department of Medicine.
authors.forename: Christine
authors.initials: C
authors.lastname: McBurney
authors.affiliation: Thoracic Pathology, Department of Pathology.
authors.forename: Frank
authors.initials: F
authors.lastname: Schneider
authors.affiliation: Thoracic Pathology, Department of Pathology.
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Yousem
authors.affiliation: Division of Pulmonary and Critical Care, Department of Medicine.
authors.forename: Kevin F
authors.initials: KF
authors.lastname: Gibson
authors.affiliation: Division of Pulmonary and Critical Care, Department of Medicine.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Lindell
authors.affiliation: Thoracic Imaging, Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
authors.forename: Carl R
authors.initials: CR
authors.lastname: Fuhrman
authors.affiliation: Division of Rheumatology and Clinical Immunology, Department of Medicine.
authors.forename: Chester V
authors.initials: CV
authors.lastname: Oddis
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002423:Cause of Death; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000401:mortality* / Q000473:pathology; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009220:Myositis / Q000453:epidemiology*; D011379:Prognosis; D016016:Proportional Hazards Models; D012042:Registries; D012131:Respiratory Insufficiency / Q000401:mortality*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
keywords: anti-synthetase syndrome; idiopathic pulmonary fibrosis (IPF); interstitial lung disease (ILD); myositis; prognosis; survival; usual interstitial pneumonia (UIP)