Compliance to continuous positive airway pressure therapy in a group of Portuguese patients with obstructive sleep apnea syndrome

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is an emerging public health concern. Although different treatments for OSAHS had been proposed, continuous positive airway pressure (CPAP) is the first-line treatment in moderate to serious OSAHS in which success can be achieved by increasing compliance to CPAP. This study analyzes long-term CPAP compliance in patients with OSAHS on CPAP therapy for at least 1 month, who began CPAP therapy between January 2004 and December 2006, followed up at a Portuguese Sleep Outpatient Clinic in Santo Antnio Hospital. Only effective data of CPAP use had been considered. During the first year of CPAP therapy, 96 patients were enrolled and followed up, but 15 patients had discontinued CPAP treatment. CPAP was used on average 5.1 h per day and in 80.1% of the total follow-up days. When compliance is defined as the use of CPAP for a minimum of 4 h per day in at least 70% of the follow-up days, only 54% of patients were classified as compliants during the first year. No statistically significant differences were found throughout the first year (p > 0.05) in terms of the percentage of compliants, controlling for demographic and clinic variables. None of the demographic and clinical baseline variables studied were found to be significant predictor of CPAP compliance (p > 0.05). This study diagnosed a low compliance to CPAP therapy in the studied sample, warning to the need of developing further studies in this area and to the need of implementing strategies to increase CPAP compliance.