title: Variability in Asthma Inflammatory Phenotype in Induced Sputum. Frequency and Causes.
abstract: BACKGROUND
  Recent studies have found variability in asthma inflammatory phenotypes determined by the inflammatory cells in induced sputum (IS). The aim of this study was to determine the frequency and factors affecting inflammatory phenotype variability in IS.
  
  
  METHODS
  Retrospective observational study that included 61 asthmatic patients who underwent at least two IS tests over a period of 5 years. They were classified according to their baseline inflammatory phenotype and subsequently grouped according to phenotype variability (persistent eosinophilic, persistent non-eosinophilic and intermittent eosinophilic). Demographic, clinical and functional data and factors potentially influencing IS variability were collected in all cases.
  
  
  RESULTS
  Of the 61 patients, 31 (50.8%) had a change with respect to baseline inflammatory phenotype. Of these, 16 (51.6%) were eosinophilic, 5 (16.1%) neutrophilic, 1 (3.2%) mixed and 9 (29.1%) paucigranulocytic. According to phenotype variability, 18 patients (29.5%) were classified as persistent eosinophilic, 17 (27.9%) non-persistent eosinophilic, and 26 (42.6%) intermittent eosinophilic. Smoking and recent asthma exacerbation were significantly associated with increased risk of variability of the IS inflammatory phenotype (OR=6.44; p=.013; 95% CI=1.49-27.80 and OR=5.84; p=.022; 95% CI=1.29-26.37, respectively).
  
  
  CONCLUSIONS
  Half of asthma patients, predominantly those with eosinophilic phenotype, present a change in IS inflammatory phenotype. This variability is associated with smoking and recent asthma exacerbation. Data suggest these factors can modify the classification of IS inflammatory phenotype in clinical practice.
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Suárez-Cuartín
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España. Electronic address: acrespo@santpau.cat.
authors.forename: Astrid
authors.initials: A
authors.lastname: Crespo
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Eder
authors.initials: E
authors.lastname: Mateus
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Torrejón
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Jordi
authors.initials: J
authors.lastname: Giner
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Alicia
authors.initials: A
authors.lastname: Belda
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: David
authors.initials: D
authors.lastname: Ramos-Barbón
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Alfons
authors.initials: A
authors.lastname: Torrego
authors.affiliation: Servicio de Neumología, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomédica Sant Pau (IIB Sant Pau), Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Vicente
authors.initials: V
authors.lastname: Plaza
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000235:genetics* / Q000276:immunology*; D004804:Eosinophils; D006801:Humans; D008875:Middle Aged; D009504:Neutrophils; D010641:Phenotype; D012189:Retrospective Studies; D013183:Sputum / Q000166:cytology*; D055815:Young Adult
keywords: Asma; Asthma; Eosinophils; Eosinófilos; Esputo inducido; Fenotipo; Induced sputum; Neutrophils; Neutrófilos; Phenotype