title: A Comprehensive Analysis of the Impact of Pseudomonas aeruginosa Colonization on Prognosis in Adult Bronchiectasis.
abstract: BACKGROUND
  Eradication and suppression of Pseudomonas aeruginosa is a key priority in national guidelines for bronchiectasis and is a major focus of drug development and clinical trials. An accurate estimation of the clinical impact of P. aeruginosa in bronchiectasis is therefore essential.
  
  
  METHODS
  Data derived from 21 observational cohort studies comparing patients with P. aeruginosa colonization with those without it were pooled by random effects meta-analysis. Data were collected for key longitudinal clinical outcomes of mortality, hospital admissions, exacerbations, and lung function decline, along with cross-sectional outcomes such as quality of life.
  
  
  RESULTS
  In the aggregate, the included studies comprised 3,683 patients. P. aeruginosa was associated with a highly significant and consistent increase in all markers of disease severity, including mortality (odds ratio [OR], 2.95; 95% confidence interval [CI], 1.98-4.40; P < 0.0001), hospital admissions (OR, 6.57; 95% CI, 3.19-13.51; P < 0.0001), and exacerbations (mean difference, 0.97/yr; 95% CI, 0.64-1.30; P < 0.0001). The patients with P. aeruginosa also had worse quality of life on the basis of their St. George's Respiratory Questionnaire results (mean difference, 18.2 points; 95% CI, 14.7-21.8; P < 0.0001). Large differences in lung function and radiological severity were also observed. The definitions of colonization were inconsistent among the studies, but the findings were robust regardless of the definition used.
  
  
  CONCLUSIONS
  P. aeruginosa is associated with an approximately threefold increased risk of death and an increase in hospital admissions and exacerbations in adult bronchiectasis.
authors.affiliation: 1 Tayside Respiratory Research Group, University of Dundee, Ninewells Hospital and Medical School, Dundee, United Kingdom.
authors.forename: Simon
authors.initials: S
authors.lastname: Finch
authors.affiliation: 2 Department of Respiratory Medicine, Galway University Hospitals, Galway, Ireland; and.
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: McDonnell
authors.affiliation: 1 Tayside Respiratory Research Group, University of Dundee, Ninewells Hospital and Medical School, Dundee, United Kingdom.
authors.forename: Hani
authors.initials: H
authors.lastname: Abo-Leyah
authors.affiliation: 3 Department of Health Science, University of Milan-Bicocca, Pneumology Clinic, San Gerardo Hospital, Monza, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Aliberti
authors.affiliation: 1 Tayside Respiratory Research Group, University of Dundee, Ninewells Hospital and Medical School, Dundee, United Kingdom.
authors.forename: James D
authors.initials: JD
authors.lastname: Chalmers
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001987:Bronchiectasis / Q000150:complications*; D018450:Disease Progression; D006760:Hospitalization; D006801:Humans; D064887:Observational Studies as Topic; D016017:Odds Ratio; D011379:Prognosis; D011552:Pseudomonas Infections / Q000188:drug therapy* / Q000453:epidemiology*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D011788:Quality of Life; D013183:Sputum / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents
keywords: bacteria; bronchiectasis; exacerbations; mortality; severity