Obstructive sleep apnea: The key for a better asthma control?

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.