Variability in Asthma Inflammatory Phenotype in Induced Sputum. Frequency and Causes

Guillermo Suárez-Cuartín, Astrid Crespo, Eder Mateus, Montserrat Torrejón, Jordi Giner, Alicia Belda, David Ramos-Barbón, Alfons Torrego, Vicente Plaza

Research output: Contribution to journalArticleResearchpeer-review

9 Citations (Scopus)


© 2014 SEPAR. Introducción: Métodos: Resultados: Conclusión: Introduction: 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). Conclusion: 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.
Original languageEnglish
Pages (from-to)76-81
JournalArchivos de Bronconeumologia
Issue number2
Publication statusPublished - 1 Feb 2016


  • Asthma
  • Eosinophils
  • Induced sputum
  • Neutrophils
  • Phenotype


Dive into the research topics of 'Variability in Asthma Inflammatory Phenotype in Induced Sputum. Frequency and Causes'. Together they form a unique fingerprint.

Cite this