Most adults need seven to eight hours of sleep per night. People who are well rested feel alert and do not have the urge to nap.

What Causes Sleep Deprivation?

• Not allowing enough time for sleep
• Anything that causes insomnia or poor quality sleep
• Sleep disorders
• Excessive worry, depression
• Repeated awakenings from noise
• Working at night, travel across time zones
• Medical illness causing pain, difficulty breathing, etc.

• Obstructive sleep apnea: A very common disorder where there is obstruction of the nose and/or throat by enlarged tonsils, a deviated nasal septum, etc., which results in pauses in breathing during sleep. Symptoms include snoring, morning headache and daytime fatigue. Obstructive sleep apnea can lead to heart failure and is a risk factor for heart attacks and strokes.

• Nocturnal myoclonus: Jerking of legs during sleep which causes brief awakenings. This causes insomnia and daytime sleepiness.

• Narcolepsy: A relatively rare sleep disorder of dream sleep. The main symptom is uncontrollable sleepiness during the day.

• Motor vehicle accidents and work accidents
• Decreased productivity

When Are Accidents Related to Sleep Deprivation Most Likely to Happen?

In the early to mid-afternoon and in the very early morning hours. These are the times when everyone is least alert.

What Other Problems Cause Excessive Daytime Sleepiness?

• Medical illnesses: heart disease, breathing disorders and a variety of other problems can cause fatigue and sleepiness.

• Mental illness: depression is an important cause of insomnia troubles during the day.

Getting enough sleep at night or adding naps in the afternoon when needed can help prevent serious accidents due to sleepiness. If a person has signs of a sleep disorder or has their sleep disrupted by symptoms of a medical illness or depression, they should see their physician.

Epworth Sleepiness Scale In contrast to just feeling tired, how likely are you to doze off or fall asleep in the following situations? (Even if you have not done some of these things recently, try to work out how they would have affected you.) Use the following scale to choose the most appropriate number for each situation. 0 = Would never doze 1 = Slight chance of dozing 2 = Moderate chance of dozing 3 = High chance of dozing
Situation	Chance of Dozing
Sitting and Reading
Watching TV
Sitting inactive in a public place (i.e. theatre)
As a car passenger for an hour without a break
Lying down to rest in the afternoon
Sitting and talking to someone
Sitting quietly after lunch without alcohol
In a car, while stopping for a few minutes in traffic
A score of greater than 10 is a definite cause for concern as it indicates significant excessive daytime sleepiness.

Source: U.S. Centers for Disease Control and Prevention

Updated: April 2002

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