THE FREQUENCY OF MULTIPLE SLEEP ONSET REM PERIODS AMONG SUBJECTS WITHNO EXCESSIVE DAYTIME SLEEPINESS

The multiple sleep latency test (MSLT) is a valuable tool in the asses sment of excessive daytime sleepiness (EDS). Additionally, multiple sl eep onset rapid eye movement periods (SOREMPs) are a frequent occurren ce in patients with narcolepsy. To date, however, few studies have eva luated the frequency of SOREMPs in a population of healthy control sub jects. Subjects participating in a variety of sleep studies were scree ned with a nocturnal clinical polysomnogram, followed by the MSLT. Sub jects were required to be drug free and have no sleep-related symptoms or medical or psychiatric conditions. Of the 139 subjects who were sc reened, 24 (17%) had two or more SOREMPs. These individuals were more likely to be male, younger, and sleepier than those with one or zero S OREMPs. The etiology of two or more SOREMPs in healthy controls was no t apparent from the clinical or polysomnographic evaluation. Although it is possible that these findings are early signs of narcolepsy, subj ects reported being free of any sleep-related complaints. Further inve stigations into the determinants of multiple SOREMPs and their reliabi lity among asymptomatic populations are warranted.