Annual decline in forced expiratory volume and airway inflammatory cells and mediators in a general population-based sample

BMC Pulm Med. 2019 May 9;19(1):90. doi: 10.1186/s12890-018-0765-7.


Background: Few studies have examined the relationships between sputum inflammatory markers and subsequent annual decline in forced expiratory volume in 1 s (dFEV1). This study investigated whether indices of airway inflammation are predictors of dFEV1 in a general population-based sample.

Methods: The study, conducted from 2003 to 2005, included 120 healthy Norwegian subjects aged 40 to 70 years old. At baseline, the participants completed a self-administered respiratory questionnaire and underwent a clinical examination that included spirometry, venous blood sampling, and induced sputum examination. From 2015 to 2016, 62 (52%) participants agreed to a follow-up examination that did not include induced sputum examination. Those with a FEV1/forced vital capacity (FVC) ratio < 0.70 underwent a bronchial reversibility test. The levels of cytokines, pro-inflammatory M1 macrophage phenotypes were measured in induced sputum using bead-based multiplex analysis. The associations between cytokine levels and dFEV1 were then analysed.

Results: The mean dFEV1 was 32.9 ml/year (standard deviation 26.3). We found no associations between dFEV1 and the baseline indices of sputum inflammation. Seven participants had irreversible airflow limitation at follow-up. They had lower FEV1 and gas diffusion at baseline compared with the remaining subjects. Moreover, two of these individuals had a positive reversibility test and sputum eosinophilia at baseline.

Conclusions: In this cohort of presumably healthy subjects, we found no associations between sputum inflammatory cells or mediators and dFEV1 during 10 years of follow-up.

Keywords: Airway inflammation; Annual decline in forced expiratory volume; Healthy individuals; Induced sputum; Sputum cells; Sputum cytokines and chemokines.

MeSH terms

  • Adult
  • Aged
  • Cytokines / analysis
  • Female
  • Forced Expiratory Volume*
  • Healthy Volunteers
  • Humans
  • Inflammation Mediators / analysis
  • Lung / physiology*
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Norway
  • Regression Analysis
  • Spirometry
  • Sputum / chemistry*
  • Vital Capacity*


  • Cytokines
  • Inflammation Mediators