A normative study of the maintenance of wakefulness test (MWT)

Sleep Disorders Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Electroencephalography and Clinical Neurophysiology 12/1997; 103(5):554-62. DOI: 10.1016/S0013-4694(97)00010-2
Source: PubMed


The maintenance of wakefulness test (MWT) is a daytime polysomnographic procedure which quantifies wake tendency by measuring the ability to remain awake during soporific circumstances. We present normative data based on 64 healthy subjects (27 males and 37 females) who adhered to uniform MWT procedural conditions including polysomnographic montage, illuminance level, seating position, room temperature, meal timing, and subject instructions. When allowed a maximum trial duration of 40 min, subjects' mean sleep latency to the first epoch of sustained sleep was 35.2 +/- 7.9 min. The lower normal limit, defined as two standard deviations below the mean, was 19.4 min. Calculation of data on the basis of a maximum trial duration of 20 min and sleep latency to the first appearance of brief sleep (a microsleep episode or one epoch of any stage of sleep) yielded a mean sleep latency of 18.1 +/- 3.6 min and a lower normal limit of 10.9 min. Sleep latency scores were significantly higher than those previously reported in patients with disorders of excessive somnolence. Therefore, the MWT appears to be a useful procedure in differentiating groups with normal daytime wake tendency from those with impaired wake tendency and in identifying individuals with pathologic inability to remain awake under soporific circumstances.

Download full-text


Available from: R Bart Sangal, Jul 04, 2014
29 Reads
  • Source
    • "Repeatable Battery for the Assessment of Neuropsychological Performance (RBANS) [44]. The RBANS is one of the most commonly-used measures of neuro/cognitive functioning in brain injury research, with well-established and documented psychometric properties. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Objective: To longitudinally examine objective and self-reported outcomes for recovery of cognition, communication, mood and participation in adults with traumatic brain injury (TBI) and co-morbid post-traumatic sleep/wake disorders. Design: Prospective, longitudinal, single blind outcome study. Setting: Community-based. Participants: Ten adults with moderate-severe TBI and two adults with mild TBI and persistent symptoms aged 18-58 years. Six males and six females, who were 1-22 years post-injury and presented with self-reported sleep/wake disturbances with onset post-injury. Interventions: Individualized treatments for sleep/wake disorders that included sleep hygiene recommendations, pharmacological interventions and/or treatments for sleep apnea with follow-up. Main outcome measures: Insomnia Severity Index, Beck Depression and Anxiety Inventories, Latrobe Communication Questionnaire, Speed and Capacity of Language Processing, Test of Everyday Attention, Repeatable Battery for the Assessment of Neuropsychological Status, Daily Cognitive-Communication and Sleep Profile. Results: Group analysis revealed positive trends in change for each measure and across sub-tests of all measures. Statistically significant changes were noted in insomnia severity, p = 0.0003; depression severity, p = 0.03; language, p = 0.01; speed of language processing, p = 0.007. Conclusions: These results add to a small but growing body of evidence that sleep/wake disorders associated with TBI exacerbate trauma-related cognitive, communication and mood impairments. Treatment for sleep/wake disorders may optimize recovery and outcomes.
    Brain Injury 09/2013; 27(12). DOI:10.3109/02699052.2013.823663 · 1.81 Impact Factor
  • Source
    • "During two or four 20- or 40-minute sessions, the patient sits in bed and attempts to remain awake. The most sensitive four-trial 40-minute MWT protocol considers latency <19 minutes as abnormal [17,18]. In rare circumstances, prolonged 24-hour continuous sleep recording is required to assess the degree of sleepiness. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The associations between depressive symptoms and hypersomnia are complex and often bidirectional. Of the many disorders associated with excessive sleepiness in the general population, the most frequent are mental health disorders, particularly depression. However, most mood disorder studies addressing hypersomnia have assessed daytime sleepiness using a single response, neglecting critical and clinically relevant information about symptom severity, duration and nighttime sleep quality. Only a few studies have used objective tools such as polysomnography to directly measure both daytime and nighttime sleep propensity in depression with normal mean sleep latency and sleep duration. Hypersomnia in mood disorders, rather than a medical condition per se, is more a subjective sleep complaint than an objective finding. Mood symptoms have also been frequently reported in hypersomnia disorders of central origin, especially in narcolepsy. Hypocretin deficiency could be a contributing factor in this condition. Further interventional studies are needed to explore whether management of sleep complaints improves mood symptoms in hypersomnia disorders and, conversely, whether management of mood complaints improves sleep symptoms in mood disorders.
    BMC Medicine 03/2013; 11(1):78. DOI:10.1186/1741-7015-11-78 · 7.25 Impact Factor
  • Source
    • ") [7] [28]. MSLT and MWT were performed according to the practice parameters for the evaluation of objective sleepiness for research purposes, with interruption of single tests after the occurrence of three consecutive epochs of stage 1 sleep or any other sleep stage (Sustained Sleep Latency – SusSL) to avoid interfering with the sleep homeostatic process , or after 20 0 (for the MSLT) and 40 0 (for the MWT) if SusSL did not occur [1] [8] [9]. Each exam consisted of four single tests performed at 10:00, 12:00, 14:00 and 16:00. "
    [Show abstract] [Hide abstract]
    ABSTRACT: To determine whether automatic slow eye movement (SEM) analysis performs comparably to standard sleep onset criteria at the multiple sleep latency test (MSLT) and at the maintenance of wakefulness test (MWT) in patients with obstructive sleep apnea syndrome (OSAS). We compared sleep latencies obtained upon standard analysis of MSLT and MWT recordings with automatically detected SEM latencies in a population of 20 severe OSAS patients that randomly underwent the two tests 1 week apart. Eight of 20 OSAS patients had EDS as answered by the Epworth Sleepiness Scale (ESS). Mean SEM latency performed comparably to standard sleep onset in both the MSLT (6.4+/-5.5 min versus 7.4+/-5.1 min, p=0.25) and the MWT (25.2+/-14.5 min versus 24.4+/-14.0 min, p=0.45) settings. Mean SEM latency significantly correlated with the sleep latency at the MSLT (r=0.52, p<0.05) and at the MWT (r=0.74, p<0.001). Finally, the Epworth Sleepiness Scale score correlated with SEM latency at the MWT (r=-0.62, p<0.01), but not at the MSLT. Automatic SEM detection performed comparably to standard polysomnographic assessment of sleep onset, thus providing a simplified technical requirement for the MSLT and the MWT. Further studies are warranted to evaluate SEM detection of sleep onset in other sleep disorders with excessive daytime sleepiness.
    Sleep Medicine 02/2010; 11(3):253-7. DOI:10.1016/j.sleep.2009.05.020 · 3.15 Impact Factor
Show more