title: Treatment and demographic factors affecting time to next pulmonary exacerbation in cystic fibrosis.
abstract: BACKGROUND
  Pulmonary exacerbations (PEx) are important CF clinical events.
  
  
  METHODS
  We studied time to next PEx following intravenous (IV) antibiotic PEx treatment among Cleveland Ohio CF center patients occurring between January 2010 and September 2014. Patient demographics, clinical presentations, and treatments were modeled by Cox proportional hazards regression to identify covariates associated with time to next PEx.
  
  
  RESULTS
  193 patients were treated for PEx; 155 had a subsequent IV-treated PEx. Six covariates were associated with future PEx hazard: number of PEx in the prior year (hazard ratio 25.1 for ≥3 and 4.4 for 1-2 prior-year PEx versus none; P<.0001), IV treatment duration in weeks (1.2; P=.0004), percent hospital treatment (1.1; P=.0018), and chronic inhaled aminoglycosides (2.5; P<.0001), leukotriene modifiers (1.8; P=.0031), and high dose ibuprofen (0.52; P=.0006).
  
  
  CONCLUSIONS
  Time to next PEx was profoundly associated with prior-year PEx, suggestive of high-risk PEx phenotypes that warrant recognition and further study.
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland, OH, USA. Electronic address: drv15@case.edu.
authors.forename: Donald R
authors.initials: DR
authors.lastname: VanDevanter
authors.affiliation: ICON Clinical Research, San Francisco, CA, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Pasta
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland, OH, USA; Rainbow Babies and Children's Hospital, Cleveland, OH, USA.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Konstan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000150:complications* / Q000188:drug therapy*; D018450:Disease Progression; D006801:Humans; D007223:Infant; D008171:Lung Diseases / Q000209:etiology*; D008875:Middle Aged; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents
keywords: Cystic fibrosis; Pulmonary exacerbation phenotype