Reversible airway obstruction in cystic fibrosis: Common, but not associated with characteristics of asthma

Background As asthma-like symptoms are common in CF, we evaluated reversible airway obstruction and associated characteristics. Methods Retrospective analysis of charts including spirometry and bronchodilator response. Results Of 190 CF patients (103 at Schneider's, 87 at Hadassah), aged 14.4 (4–76) years, median (range), 39% had reversible obstruction (ΔFEV₁% predicted ≥ 12%), associated with younger age (p = 0.01) and severe genotype (p = 0.02). There was no association with family history of asthma, serum IgE, blood eosinophils, pancreatic status, FEV₁ < 40% predicted, Aspergillus or pseudomonas infection. Of patients with reversible obstruction, 74% were on bronchodilator and 68% on inhaled corticosteroid therapy but 54% and 57% respectively receiving these therapies did not have reversible obstruction. Conclusions Reversible airway obstruction is common in CF, more frequent in younger patients and with severe genotype, with no correlation to markers of atopy or CF clinical severity. Bronchodilator and inhaled corticosteroid therapies are commonly prescribed even without reversible obstruction.