http://www.ncbi.nlm.nih.gov/pubmed/19410510?ordinalpos=13&itool...

BACKGROUND: Patients with obstructive sleep apnea syndrome (OSAS) are known to have an increased risk for motor vehicle crashes. They suffer from sleep-related respiratory abnormality causing repetitive arousal leading to daytime sleepiness. In turn, it has been demonstrated that sleepiness can impair human psychomotor performance causing slowing of reaction times (RTs). Patients with OSAS present with RTs comparable to young adults under the influence of blood alcohol concentrations above the legally permitted level to drive a motor vehicle. Vigilance related risk levels in patients with upper airway resistance syndrome (UARS) and potential deficits in psychomotor performance are unknown. METHODS: We designed a study to compare psychomotor performance in UARS and compared it to patients with OSAS. Forty-seven UARS patients were matched by gender and age with 47 OSAS patients. All subjects completed a standardized vigilant attention task utilizing reaction time before undergoing polygraphic sleep studies. RESULTS: Patients with UARS presented worse psychomotor performance on most test metrics than patients with OSAS. CONCLUSIONS: Our study results may suggest that patients with UARS may also present an increased risk for motor vehicle crashes as previously demonstrated in OSAS patients.