Bronchial asthma (BA) and obstructive sleep apnea syndrome (OSAS) are common causes of respiratory disturbance. Many cases of patients with both conditions have been reported, and BA and OSAS may exacerbate each other, but information remains sparse.We retrospectively evaluated 60 patients under treatment for BA in our department between April 2016 and March 2018 who also underwent portable polysomnography (PSG) for suspected OSAS to assess potential association between PSG results and asthma treatment or respiratory function. BA was diagnosed and treated according to the Asthma Prevention and Management Guideline 2015. We found that BA treatment intensity step was significantly higher for patients with BA who had concurrent moderate or severe OSAS ( = 0.0016). However, neither respiratory function, fraction of exhaled nitric oxide (FeNO), nor forced oscillation technique (FOT) differed significantly between patients with and without OSAS, and apnea hypopnea index was not significantly correlated with respiratory function, FeNO or FOT parameters.We conclude that even though BA patients with OSAS had good respiratory function, their BA was more severe than that of patients without OSAS, suggesting that OSAS may exacerbate BA. Background factors and asthma parameters were not predictive of PSG results, and patients with suspected OSAS should be evaluated proactively by using PSG.

INTRODUCTION:Obstructive sleep apnea (OSA) is an important risk factor for poor asthma control. The objective of this study is to analyze the symptomatic control in asthmatic patients with OSA after using continuous positive airway pressure (CPAP). METHODS:Patients were collected in a monographic asthma consult and a polygraphy was performed due to clinical suspicion or poor disease control. Asthma associated pathologies, as well as clinical and patient-perceived asthma control parameters were evaluated before and after the initiation of CPAP. RESULTS:A hundred patients were included, 59% were women and 41% men. From them, 54% had severe OSA, 33% moderate OSA and 13% mild OSA, and 10% could not tolerate CPAP. Eighty four percent had a moderate or severe degree of asthma with fractional exhaled nitric oxide (FENO) 32 ± 24.6 ppm and an asthma control test (ACT) before CPAP of 19 ± 4. Asthma control before CPAP was good in 41% of patients, partial in 29%, and bad in 30%. After three or more months of CPAP, clinical asthma control was good in 70% (p < 0.001), perceived control by ACT after CPAP was 21 ± 4 (p < 0.001). When asked for their opinion, 51.5% referred clinical improvement after CPAP, no change in 46.5%. CONCLUSIONS:The use of CPAP in asthmatic patients with OSA improves both clinical and perceived asthma control in a statistically significant way. Most patients had good adaptation to CPAP (90%) and 51.5% had clinical improvement.