Chapter 3 - Assessment of daytime sleepiness

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Publisher Summary

Excessive daytime sleepiness (EDS) is a common symptom of insufficient sleep, inadequate sleep, intrinsic sleep disorders, and many other medical conditions. Patients who suffer from EDS are common in the practices of primary care physicians, many types of specialists, and particularly sleep medicine specialists. To provide an appropriate diagnosis and effective treatment options, careful assessment by history, physical examination, and other approaches is often necessary. Repeated assessments may be necessary to track changes in EDS and response to treatment over time. A National Sleep Foundation poll in 2002 suggested that 37% of adults are so sleepy during the day that it interferes with their daily activities a few days a month or more; 16% experience this level of daytime sleepiness a few days a week or more. It was found that 51%percent of the polled subjects reported driving while drowsy and 17% have dozed off while driving. Increased subjective daytime somnolence and chronically disrupted sleep also have been associated with an increase in estimated healthcare use. Findings demonstrated that sleep attacks and irresistible sleepiness were more specific and sensitive for short mean sleep latencies on formal testing than tiredness or resistible sleepiness.

Introduction

Excessive daytime sleepiness (EDS) is a common symptom of insufficient sleep, inadequate sleep, intrinsic sleep disorders, and many other medical conditions. Defined as “a subjective report of difficulty in maintaining the alert, awake state,” sleepiness becomes excessive when it occurs during inappropriate settings (American Academy of Sleep Medicine, 2001).

Patients who suffer from EDS are common in the practices of primary care physicians, many types of specialists, and particularly sleep medicine specialists. To provide an appropriate diagnosis and effective treatment options, careful assessment by history, physical examination, and other approaches is often necessary. Repeated assessments may be necessary to track changes in EDS and response to treatment over time.

Perhaps in part because it is nearly a universal experience, sleepiness is often ignored or minimized by patients. A National Sleep Foundation poll in 2002 suggested that 37% of adults are so sleepy during the day that it interferes with their daily activities a few days a month or more; 16% experience this level of daytime sleepiness a few days a week or more. Fifty-one percent of the polled subjects reported driving while drowsy, and 17% have dozed off while driving. Increased subjective daytime somnolence and chronically disrupted sleep also have been associated with an increase in estimated healthcare use (Kapur et al., 2002).

People with chronically insufficient or inadequate sleep may have many complaints other than “sleepiness,” such as fatigue, lack of energy, and tiredness. Though patients may not distinguish between these expressions, clinicians may find some utility in encouraging patients to be more specific. Synonyms for sleepiness may be useful, such as drowsiness, tendency to fall asleep, and decreased alertness; additional terms for fatigue are weariness, weakness, and depleted energy (Pigeon et al., 2003). Sleep disorders such as obstructive sleep apnea or narcolepsy are often thought to be associated primarily with EDS. However, patients with sleep apnea often complain more about lack of energy than EDS (Chervin, 2000). Attempting to compare alternative definitions of sleepiness, Rinaldi et al. (2001) assessed tiredness, resistible sleepiness, irresistible sleepiness, and sleep attacks by questionnaire in a group of patients referred for complaints of daytime sleepiness or possible sleep-disordered breathing. Findings demonstrated that sleep attacks and irresistible sleepiness were more specific and sensitive for short mean sleep latencies on formal testing than tiredness or resistible sleepiness.

Section snippets

History

Some patients ask to be evaluated for EDS, but many patients, after years of suffering from sleepiness, do not realize that this state is not normal. Falling asleep at work or during social activities can become commonplace for some individuals who may not come to attention unless persuaded to seek help by friends, significant others, or near-miss motor vehicle crashes. Such patients may require detailed inquiry to elicit symptoms of EDS. Areas to explore include the length of time patients

Physical Examination

Frequently, the physical examination of the patient with EDS reveals no specific findings. Patients with severe sleepiness may fall asleep in a waiting room or nod off during a lull in conversation. Other behavioral signs of sleepiness may include yawning, ptosis, reduced activity, lapses in attention, and head-nodding (Roehrs et al., 2000). Dark or baggy circles under the eyes are often thought to represent a sign of sleepiness, but few studies have been performed to evaluate, confirm, or

Subjective Testing

Several standardized methods for assessment of daytime sleepiness exist, but the most commonly used is the Epworth Sleepiness Scale (ESS) (Table 3.3). The ESS evaluates a patient’s self-report of sleepiness by asking about the likelihood of a patient dozing in eight different sedentary situations. The Likert response scale ranges from 0 (“would never doze”) to 3 (“high chance of dozing”). The sum of the eight item responses then quantifies subjective sleep propensity “in recent times” (Johns,

Nocturnal Polysomnography

The overnight polysomnogram often plays a central role in the diagnostic process. Findings that may help assess the severity of EDS include a short sleep latency and increased sleep efficiency. In a study of 147 referred patients, the only factor among demographic information, polysomnographic data, and subjective assessments that was found to correlate significantly with mean sleep latency on the MSLT was sleep latency on overnight polysomnography (Chervin et al., 1995). Arousals or hypoxia

Multiple Sleep Latency Test

The MSLT is considered the standard, for objective assessment of EDS, to which all other measures are compared. Developed by Carskadon & Dement in the 1970s at Stanford University, this test was described as a test of physiological sleep tendency. The MSLT measures the speed with which a patient is able to fall asleep in a controlled environment at time points spread throughout the day (Carskadon and Dement, 1977). The guidelines for the tests were later revised in 1986 and some pretest

Maintenance of Wakefulness Test

The Maintenance of Wakefulness Test (MWT) is a variation of the MSLT designed to assess an individual’s ability to remain awake during sleep-inducing circumstances. The patient, seated in bed within a dimly lit and quiet room, is told to “sit still and remain awake” rather than to “try to fall asleep,” as in an MSLT. As initially described, the subject is monitored for sleep onset during five sessions, each lasting 20 or 40 minutes, scheduled at 2-hour intervals, beginning 2 hours after

Other Testing

Pupillometry measures the spontaneous variation of the pupil diameter and the pupillary light reflex. Sleepiness-related alterations in spontaneous pupil behavior in a dark environment were described by Lowenstein & Loewenfeld in 1958. Later, Yoss et al. (1969) discovered pupillary changes in patients with narcolepsy. More recent studies have confirmed these earlier reports, and have attempted to increase the objectivity of pupillometry (Wilhelm et al., 1998). Increase in spontaneous pupil

Practical Applications

Although most patients referred to a sleep disorders clinic have a chief complaint of EDS, assessment of this problem by a careful history is usually sufficient to estimate the severity and impact. Most of the diagnostic challenge centers on the determination of underlying causes. An ESS can provide a quick, inexpensive, and repeatable quantification of subjective sleepiness. A nocturnal polysomnogram is often indicated to identify root causes for abnormal sleepiness, when such causes are not

References (72)

  • L. Findley et al.

    Vigilance and automobile accidents in patients with sleep apnea or narcolepsy

    Chest

    (1995)
  • S. Fulda et al.

    Cognitive dysfunction in sleep disorders

    Sleep Med Rev

    (2001)
  • T.F. Hoban et al.

    Assessment of sleepiness in children

    Semin Pediatr Neurol

    (2001)
  • E.O. Johnson et al.

    Psychometric evaluation of daytime sleepiness and nocturnal sleep onset scales in a representative community sample

    Biol Psychiatry

    (1999)
  • J.W. McLaren et al.

    Pupillometry in clinically sleepy patients

    Sleep Med

    (2002)
  • M.M. Mitler et al.

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

    Electroencephalogr Clin Neurophysiol

    (1982)
  • M.M. Mitler et al.

    The maintenance of wakefulness test: normative data by age

    J Psychosom Res

    (2000)
  • W. Pigeon et al.

    Distinguishing between excessive daytime sleepiness and fatigue: toward improved detection and treatment

    J Psychosom Res

    (2003)
  • J.S. Poceta et al.

    Maintenance of wakefulness test in obstructive sleep apnea syndrome

    Chest

    (1992)
  • L. Rosenthal et al.

    The sleep–wake activity inventory: a self-report measure of daytime sleepiness

    Biol Psychiatry

    (1993)
  • T. Akerstedt et al.

    Subjective and objective sleepiness in the active individual

    Int J Neurosci

    (1990)
  • American Academy of Sleep Medicine

    International Classification of Sleep Disorders, revised: Diagnostic and Coding Manual

    (2001)
  • American Academy of Sleep Medicine

    International Classification of Sleep Disorders

    (2005)
  • C. Bassetti et al.

    Idiopathic hypersomnia: a series of 42 patients

    Brain

    (1997)
  • S.R. Benbadis et al.

    Association between the Epworth sleepiness scale and the multiple sleep latency test in a clinical population

    Ann Intern Med

    (1999)
  • L.S. Bennett et al.

    A behavioural test to assess daytime sleepiness in obstructive sleep apnoea

    J Sleep Res

    (1997)
  • M.H. Bonnet et al.

    Sleepiness as measured by modified multiple sleep latency testing varies as a function of preceding activity

    Sleep

    (1998)
  • R. Broughton et al.

    A comparison of multiple and single sleep latency and cerebral evoked potentials (P300) measures in the assessment of excessive daytime sleepiness in narcolepsy-cataplexy

    Sleep

    (1988)
  • M.A. Carskadon et al.

    Sleep tendency: an objective measure of sleep loss

    Sleep Res

    (1977)
  • M.A. Carskadon et al.

    Cumulative effects of sleep restriction on daytime sleepiness

    Psychophysiology

    (1981)
  • M.A. Carskadon et al.

    Guidelines for the multiple sleep latency test (MSLT): a standard measure of sleepiness

    Sleep

    (1986)
  • R.D. Chervin

    Assessment of daytime sleepiness

  • R.D. Chervin et al.

    The Epworth sleepiness scale may not reflect objective measures of sleepiness or sleep apnea

    Neurology

    (1999)
  • R.D. Chervin et al.

    Sleep onset REM periods during multiple sleep latency tests in patients evaluated for sleep apnea

    Am J Respir Crit Care Med

    (2000)
  • R.D. Chervin et al.

    Subjective sleepiness and polysomnographic correlates in children scheduled for adenotonsillectomy vs. other surgical care

    Sleep

    (2006)
  • D.F. Dinges et al.

    Cumulative sleepiness, mood disturbance, and psychomotor vigilance performance decrements during a week of sleep restriction to 4–5 hours per night

    Sleep

    (1997)
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