[Daytime sleepiness in patients with Obstructive Sleep Apnoea (OSA) - pathogenetic factors].

Excessive daytime sleepiness (EDS) is one of the most frequent symptoms in patients with obstructive sleep apnoea (OSA). EDS can lead to substantial impairments in quality of life and is a major cause of fatal accidents. However, not all patients with OSA develop EDS. The aim of this paper is to review the current literature to identify factors having an impact on sleepiness in patients with OSA. Interestingly, a substantial heterogeneity of the results was found. Summarising these results, causes of EDS in patients with OSA are multifactorial. Severity of obesity and breathing disorders (apnoea/hypopnoea index) seem to be the most important predictors. Continuous positive airway pressure therapy significantly reduces sleepiness in patients with OSA.