Acute exercise in cystic fibrosis patients increases neutrophilic pulmonary inflammation

Background: Neutrophilic inflammation mainly from recurrent bacterial infection characterizes cystic fibrosis (CF) airways. Repeated inflammatory insults may lead to progressive lung function decline. Acute exercise is reported to trigger a systemic inflammatory response, but inflammation pattern has been poorly studied. As exercise is part of a healthy lifestyle, we aim to depict the modulation of inflammation after an acute exercise in CF. Methods: 12 subjects with mild to moderate stable CF (FEV1>50% of p.v.) underwent a constant load exercise test at 80% of their maximal load. Sputum and blood were sampled before and 1 hour after exercise and analysed for differential leucocyte counts. Results: 6 females and 6 males completed the study with a mean FEV1 of 72.2% and a mean exercice time of 4.6 minutes. No desaturation was reported. Table 1 summarizes the differential leucocytes counts in blood and sputum. Exercise induces a 2.2 fold increase in airway neutrophils (p=0.019) and 1.4 fold increase in blood neutrophils (p=0.01). Conclusion: We demonstrate that acute exercise increases the peripheral and airway inflammation in stable CF subjects. This burst of neutrophils might have a dual role in which it might improve local defense against infections and participate in airway destruction through release of elastase and other mediators. The modulation of this inflammatory response by exercise training has to be explored.