THE RELIABILITY OF THE DIAGNOSTIC FEATURES IN PATIENTS WITH NARCOLEPSY

This study determined the test-retest reliability of the polysomnograp hic findings in narcolepsy. The diagnosis of narcolepsy was based on c linical symptoms and polysomnographic signs. Control subjects were scr eened before participation and were split based on their screening mul tiple sleep latency test (MSLT) into high- and low-MSLT groups. Subjec ts completed two polysomnographic evaluations with at least 5 days bet ween laboratory tests. Narcoleptics had lower sleep efficiencies and h igh stage 1% when compared to the low MSLT control group. They had mor e awakenings and less stage 2% than the control groups. Narcoleptics h ad a shorter latency to I when compared to the high-MSLT group but com parable to that of the low-MSLT group. Narcoleptics had a higher numbe r of sleep-onset rapid eye movement periods (SOREMPs) than both contro l groups. The MSLT scores were stable across the two evaluations and s howed a statistically significant correlation. Twenty-eight of the 30 narcoleptic subjects had two or more SOREMPs on reevaluation. None of the controls had multiple SOREMPs. Thus, multiple SOREMPs were shown t o be a reliable finding in patients with narcolepsy.