Clinical-functional features of osmotic airway hyperresponsiveness in patients with asthma

Abstract

Introduction: Clinical and functional manifestations of osmotic airway hyperresponsiveness (OAH) may be different depending on the nature of the trigger. Aim: to study clinical-functional features of OAH in asthmatics. Methods: 3-minute ultrasonically nebulized distilled water inhalation (DWI) and 3-minute hypertonic solution (4.5% of NaCl) inhalation (HSI) were done in different days to 59 patients with moderate uncontrolled asthma; the patients also had dozed physical exercises (PE) at the treadmill LE 200C. FEV 1 was measured before and 1 and 5 minutes after provocation. Results: According to anamnestic testing at the change of the air humidity the patients had gasp (14%), shortness of breath (54%) in combination with increase of dyspnea (32%), cough (39%), hoarseness, blocked nose (19%), 34% of patients needed quick-relief medications. After DWI the symptoms of airway irritation were kept in 61% of patients, after HSI in 63%, after (PE) in 13%. The drop of FEV 1 after DWI was registered in 37% of patients (the mean ΔFEV 1 is -18.1±2.50%), after HSI in 29% (the mean ΔFEV 1 is -17.8±1.87%); after PE in 18% (the mean ΔFEV 1 is -18.9±3.30%, p>0.05). None of the patients responded to all the provocations equally by the drop of airway patency. But the patients who had a positive response to DWI in 58% had an intensive bronchial response to HSI and in 13% of cases they had a positive response to PE. Conclusion: More than 30% of asthmatics have an airway hyperresponsiveness to osmotic stimuli, in 58% there was bronchial hypersensitiveness to the combined effect of osmotic stimuli, which can be one of the causes of asthma control losing. Supported by Russian Science Foundation (grant 14-25-00019).