Residual excessive daytime sleepiness (EDS) in Italian patients with obstructive sleep apnea (OSA) treated with continuous positive airway pressure (CPAP): preliminary results of the OSAREDS study

Prevalence of residual excessive daytime sleepiness (EDS) in patients with obstructive sleep apnea (OSA) after treatment varies among studies. OSAREDS is a retrospective study involving 7 sleep Centres in Italy aimed at assessing prevalence of EDS and residual EDS after CPAP in OSA patients. An interim analysis showed that 861 patients (mean age±SD:56.5±8.8 yrs, BMI: 31.3±4.8 kg/m2, females: 25.8%) were seen at baseline and after 3-12 months (median 9.6 months) of CPAP treatment. Symptoms and compliance to CPAP were analyzed. Residual EDS was assessed as an Epworth Sleepiness Scale (ESS) score >10. Symptoms prevalence at diagnosis were: snoring 97.1%, fatigue 31.1%, insomnia 13.5%, and daytime sleepiness 36.5%; mean ESS score at diagnosis was 8.8±5.0. Mean symptoms duration was 61±41.6 months. Frequency of systemic hypertension, type 2 diabetes, asthma and COPD were 59.2, 16.0, 5.5, and 5.8%, respectively. CPAP was accepted by 98.7% of the patients, and 93.7% were on treatment at follow-up. Average therapeutic pressure was 8.3±3.7 cmH2O; mean CPAP use was 5.4±2.6 h/night for 77.7±25% of the nights. At follow-up, mean AHI was 6.1/h, mean ESS score was 4.6±3.7 (p<0.01 by t-test); prevalence of residual EDS in the whole sample fell to 6.6% (95% CI 5.0-8.3, p<0.01). Residual EDS was reported by 18% of OSA patients that had EDS at baseline. Prevalence rates of snoring, fatigue and insomnia at follow-up decreased to 12, 10.5, and 5.6%, respectively (p<0.0001 for all). Our preliminary results confirm that about one in 6 sleepy OSA patients at diagnosis remain sleepy after CPAP.