title: Suspected acute exacerbation of idiopathic pulmonary fibrosis as an outcome measure in clinical trials.
abstract: BACKGROUND
  Acute exacerbation of idiopathic pulmonary fibrosis has become an important outcome measure in clinical trials. This study aimed to explore the concept of suspected acute exacerbation as an outcome measure.
  
  
  METHODS
  Three investigators retrospectively reviewed subjects enrolled in the Sildenafil Trial of Exercise Performance in IPF who experienced a respiratory serious adverse event during the course of the study. Events were classified as definite acute exacerbation, suspected acute exacerbation, or other, according to established criteria.
  
  
  RESULTS
  Thirty-five events were identified. Four were classified as definite acute exacerbation, fourteen as suspected acute exacerbation, and seventeen as other. Definite and suspected acute exacerbations were clinically indistinguishable. Both were most common in the winter and spring months and were associated with a high risk of disease progression and short-term mortality.
  
  
  CONCLUSIONS
  In this study one half of respiratory serious adverse events were attributed to definite or suspected acute exacerbations. Suspected acute exacerbations are clinically indistinguishable from definite acute exacerbations and represent clinically meaningful events. Clinical trialists should consider capturing both definite and suspected acute exacerbations as outcome measures.
authors.affiliation: University of California San Francisco, San Francisco, CA, USA. hal.collard@ucsf.edu
authors.forename: Harold R
authors.initials: HR
authors.lastname: Collard
authors.forename: Eric
authors.initials: E
authors.lastname: Yow
authors.forename: Luca
authors.initials: L
authors.lastname: Richeldi
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Anstrom
authors.forename: Craig
authors.initials: C
authors.lastname: Glazer
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D002986:Clinical Trials as Topic / Q000379:methods*; D018450:Disease Progression; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods*; D058986:Phosphodiesterase 5 Inhibitors / Q000627:therapeutic use; D010879:Piperazines / Q000627:therapeutic use*; D011687:Purines / Q000627:therapeutic use; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate