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Sleep Facts

Daytime Sleepiness A Simple Measure for the Office

• Sleepiness during the daytime is a common problem. It generally goes unrecognized until tragedy strikes.

• Texas highways are more dangerous because of sleepiness. During 1992 it was estimated that 35,000 motor vehicle accidents occurred due to drowsy Texas drivers. Falling asleep while driving alone at night increases the risk of a fatal crash fivefold. The National Commission on Sleep Disorders Research reported in 1993 that inappropriate sleepiness during the day costs the nation over 15 billion in direct expenses and nearly 70 billion dollars in lost productivity.

• The assessment of daytime sleepiness requires a physician to have a high index of suspicion. Patients may call it "tiredness" or "fatigue". Others may not speak of their problems for fear of being labeled as "lazy". If national surveys hold true, it would be estimated that 6% of patients in a typical medical practice would have moderate to severe daytime sleepiness.

• To assist physicians in their recognition of daytime sleepiness, Dr. Murray Johns of Melbourne, Australia designed and validated the Epworth Sleepiness Scale (ESS)¹. It asks a patient to rate the chance of dozing during various daytime activities. The ESS is easy to complete and score with the cut-off points listed at the bottom of this page.

You can take the Epworth Sleepiness Test online.

Sleep & Alcohol

Macduff: What three thing does drink especially provoke?
Porter: Marry sir, nose painting, sleep, and urine... Shakespeare, Macbeth

Alcohol Has Profound Effects Upon Sleep.

During the first half of an 8-hour sleep period alcohol...

• Hastens sleep onset
• Reduces amount of REM sleep²

During the latter half of sleep period after elimination of alcohol...

• REM sleep is increased
• Wakefulness or light sleep is increased

After 3 or 4 Nights of Repeated Consumption Tolerance Develops.

Upon Discontinuation of Nightly Use, REM Sleep is Increased (Termed REM Rebound).

Recent Studies of Sleep Deprivation Demonstrate a Sleepiness-Ethanol Interaction³

• 3 drinks become the functional equivalent of six drinks after 5 nights of partial sleep deprivation.
• Extension of sleep to 10 hours per night reduces the effect of a moderate dose of alcohol.

Specific Action of Alcohol is Probably Through the Gamma-Aminobutyric acid (GABA) System.

Resources:

1. Johns MW. A new method for measuring daytime sleepiness: The Epworth Sleepiness Scale. Sleep 1991; 14(6):540-5.
2. Williams H, Salamy A 1972. Alcohol and sleep. In Kissin B, Begleiter H. Eds. The biology of alcoholism, Vol2, pp 435-83. New York: Plenum.
3. Roth T, Roehrs T, MerlottiL 1990. Ethanol and daytime sleepiness. Alocohol drugs Driving 6:357-62.