Maintenance of wakefulness test: a polysomnographic technique for evaluation treatment efficacy in patients with excessive somnolence

Abstract

Ten patients with narcolepsy were given five 20 min opportunities to remain awake throughout the day. Trials were offered at 2 h intervals beginning at 10:00. Polysomnographic variables were monitored during each trial. Sleep latency increased when patients were instructed to maintain wakefulness compared to when instructed to sleep; however, sleep latencies were still lower for narcoleptics than for control subjects. Unexpectedly, we were not always able to document patients' reports of increased ability to stay awake. The findings suggested that clinical data on symptom control in narcolepsy do not predict ability to stay awake. Objective measures of the ability are potentially more useful in evaluating treatment.

Figures

Fig. 1

Maintenance of Wakefulness test results for sleep latency as a function of time of test and for number of sleep onset REM sleep periods (REM score) averaged over the 5 tests. Data are from 8 controls and 10 drug-free narcoleptic patients.