[Coexistence of asthma and obstructive sleep apnea syndrome - review of the literature].

Both asthma and obstructive sleep apnea (OSA) syndrome are frequent diseases and their coexistence may implicate important consequences. The incidence of OSA syndrome among the patients with asthma is higher than in the general population, especially in the patients with nocturnal symptoms persisting despite treatment, in patients frequently admitted to hospital because of the exacerbations of asthma, and in obese patients. The causes of frequent coexistence of asthma and OSA syndrome are not fully elucidated. The common abnormalities possibly linking asthma and OSA syndrome include obesity, gastro-esophageal reflux, nasal obstruction, and inflammation. In some patients with asthma it would be advised to search for OSA syndrome, as obstructive sleep apneas and hypopneas may influence asthma exacerbations. Especially, OSA should be suspected in the asthma patients with the signs of ventilatory disturbances during sleep. The method of choice of treatment of the patients with OSA syndrome is continuous positive airway pressure (CPAP) applied through the nasal or full-face mask, that leads to elimination of the obstructive sleep apneas and hypopneas during sleep. CPAP treatment may also positively influence the course of asthma.