title: Association of early suspected acute exacerbations of idiopathic pulmonary fibrosis with subsequent clinical outcomes and healthcare resource utilization.
abstract: BACKGROUND
  Idiopathic pulmonary fibrosis (IPF) may be complicated by episodes of acute exacerbation. This study quantified the association between occurrence of suspected acute exacerbations of IPF (AEx-IPF) in the 6 months post-IPF diagnosis with clinical outcomes and IPF-related healthcare resource utilization (HRU).
  
  
  METHODS
  U.S. pulmonologists participated in a retrospective chart review of IPF patients. Patient eligibility criteria included: 1) ≥40 years of age and a confirmed date of first IPF diagnosis with HRCT and/or lung biopsy between January 2011-June 2013; 2) 2 separate FVC results recorded around first diagnosis and 6 months post-diagnosis. Patients with a suspected AEx-IPF within 6 months post-diagnosis were categorized as "early AEx-IPF." Subsequent clinical outcomes and IPF-related HRU were assessed from 6 months post-diagnosis until the latest physician contact date.
  
  
  RESULTS
  The sample included 490 IPF patients from 168 pulmonologists; 72 (15%) patients had a suspected early AEx-IPF. At IPF diagnosis, the mean (SD) age was 61 (11) years, 68% were male, and the mean FVC percent predicted was 60% (26%). Compared to patients without a suspected early AEx-IPF, patients with an early AEx-IPF had higher mortality risk (HR = 2.87, p < 0.001) and higher rates of subsequent suspected AEx-IPF (IRR = 3.87, p < 0.001), outpatient visits (IRR = 1.46, p < 0.001), ER visits (IRR = 4.39, p < 0.001), hospitalizations (IRR = 7.96, p < 0.001), and ICU stays (IRR = 9.74, p < 0.001).
  
  
  CONCLUSIONS
  Using a large sample of IPF patients from varied practice settings, we found a strong relationship between suspected early AEx-IPF and worse subsequent clinical outcomes and increased IPF-related HRU. This relationship was particularly pronounced for acute resource use.
authors.affiliation: Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877, USA. Electronic address: Yanni.Yu@boehringer-ingelheim.com.
authors.forename: Yanni F
authors.initials: YF
authors.lastname: Yu
authors.affiliation: Analysis Group, Inc., 10 Rockefeller Plaza, 15th Floor, New York, NY 10020, USA. Electronic address: Dendy.Macaulay@analysisgroup.com.
authors.forename: Dendy S
authors.initials: DS
authors.lastname: Macaulay
authors.affiliation: Analysis Group, Inc., 111 Huntington Avenue, 10th Floor, Boston, MA 02199, USA. Electronic address: Bill.Reichmann@gmail.com.
authors.forename: William M
authors.initials: WM
authors.lastname: Reichmann
authors.affiliation: Analysis Group, Inc., 111 Huntington Avenue, 10th Floor, Boston, MA 02199, USA. Electronic address: Eric.Wu@analysisgroup.com.
authors.forename: Eric Q
authors.initials: EQ
authors.lastname: Wu
authors.affiliation: Advanced Lung Disease and Transplant Program, Department of Medicine, Inova Fairfax Hospital, 3300 Gallows Road, Falls Church, VA 22042, USA. Electronic address: Steven.Nathan@inova.org.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Nathan
mesh_terms: D000208:Acute Disease; D017677:Age Distribution; D000553:Ambulatory Care / Q000706:statistics & numerical data; D003422:Critical Care / Q000706:statistics & numerical data; D042241:Early Diagnosis; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006295:Health Resources / Q000706:statistics & numerical data; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis* / Q000401:mortality / Q000503:physiopathology; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data; D011379:Prognosis; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology; D014797:Vital Capacity / Q000502:physiology
keywords: Acute exacerbations; FVC; Healthcare resource use; Idiopathic pulmonary fibrosis; Lung function; Mortality