[Changes in the time spent awake in obstructive sleep apnea and snoring--results of a pilot study]

Continuous positive airway pressure (CPAP) therapy reduces sleeping time per day and daytime sleepiness in obstructive sleep apnoea (OSA) and heavy snoring. Due to sleep fragmentation the OSA and heavy snoring are associated with a daytime sleepiness and increased necessity of sleep. In this pilot study the effect of CPAP-therapy on daytime sleepiness and sleep time during 24 hours were assessed in patients with OSA or heavy snoring (daytime sleepiness, none or slight apnoea with AHI < 10/h and benefit of CPAP). We studies 42 patients with OSA (AHI: 34.5 +/- 23.6) and 15 patients with heavy snoring: inclusion criteria: Patients with OSA (AHI > 10/h, ESS-Score > 8) and heavy snoring (AHI < 10/h, ESS-Score > 8) who were treated with nCPAP. Before and 2 months after initiation the CPAP-therapy all patients completed diary cards recording the sleeping time/day for 1 month; additionally they scored sleepiness using the Epworth sleepiness scale (ESS-score ranged from 0 to 24, the higher the score the worse the sleepiness) before and 2 months after initiation the CPAP-therapy. In the whole study population nCPAP-therapy reduced the sleeping time significantly by a mean period of 46 minutes per 24 hours (from 8.3 +/- 1.3 to 7.5 +/- 1.2 hours, p < 0.001) and improved the ESS score from 13.7 +/- 4.6 to 6.1 +/- 3.6 (p < 0.0001). In respect of the change of sleeping time/day and of the sleepiness score there was no significant difference between the OSA and heavy snoring group. With CPAP the AHI in OSA patients was reduced from 34.5 +/- 23.6/h to 3.2 +/- 3.2/h. Due to the improvement of sleep-related breathing disorders CPAP therapy reduced the mean sleeping time/day by approximately 10% and the daytime sleepiness score both in patients with OSA and heavy snoring compared to the pretreatment period.