Objective measurment of excessive daytime sleepiness with maintenance of wakefulness test in patients with breathing disorders during sleep

Abstract

Background: To objectively assess excessive daytime sleepiness (EDS) only Mean Sleep Latency Test (MSLT) is used in Slovenia. Research reports show that Maintenance of Wakefulness Test (MWT) is more useful for evaluating treatment results of patients with OSAS. Our aim was to compare MSLT with MWT in an objective evaluation of EDS in patients with OSAS. Methods: Twenty patients with subjective EDS and OSAS were included. Subjective EDS over a longer period was estimated using the Epworth Sleepiness Scale (ESS). Polysomnography, MSLT and MWT were performed. We evaluated subjective sleepiness using the Stanford Sleepiness Scale (SSS) before every MSLT (SSS-MSLT) and MWT (SSS-MWT). Results: 80 % of pacients had severe OSAS. ESS showed EDS in 68.4 %. The mean sleep latency (MSL) for the MSLT (MSL-MSLT) was 9 min, and for MWT (MSL-MWT) 16.5 min. There was no difference between the repeated measurements for both MWT and MSLT (p >0.05). MSLT was pathological in 85 % and MWTin 40 % . The tests did not differ in sensitivity(p > 0.05). Conclusions: MSL-MSLT significantly correlates with MSL-MWT. There is no difference inthe sensitivity between MSLT and MWT.