Sleep disorders involve any difficulties related to sleeping, including difficulty falling or staying asleep, falling asleep at inappropriate times, excessive total sleep time, or abnormal behaviors associated with sleep.
Causes, incidence, and risk factors
More than 100 different disorders of sleeping and waking have been identified. They can be grouped in four main categories:
- Problems with falling and staying asleep (insomnia)
- Problems with staying awake (excessive daytime sleepiness)
- Problems with sticking to a regular sleep schedule (sleep rhythm problem)
- Unusual behavoirs during sleep (sleep-disruptive behaviors)
PROBLEMS WITH FALLING AND STAYING ASLEEP
Common factors associated with insomnia include:
- Physical illness
-
Depression -
Anxiety or stress - Poor sleeping environment such as excessive noise or light
- Caffeine
- Alcohol or other drugs
- Use of certain medications
- Heavy smoking
- Physical discomfort
- Daytime napping
- Counterproductive sleep habits:
- Early bedtimes
- Excessive time spent awake in bed
Disorders include:
- Psychophysiological insomnia: a condition in which stress caused by the insomnia makes it even harder to fall asleep
- Delayed sleep phase syndrome: your internal clock is constantly out of synch with the "accepted" day / night phases; for example, patients feel best if they can sleep from 4AM to noon
- Hypnotic-dependent sleep disorder: insomnia that occurs when you stop or become tolerant to certain types of sleep medications
- Stimulant-dependent sleep disorder: insomnia that occurs when you stop or become dependent on certain types of stimulants
PROBLEMS WITH STAYING AWAKE
Disorders of excessive sleepiness are called
- Idiopathic hypersomnia (excessive sleepiness that occurs without an identifiable cause)
-
Narcolepsy - Obstructive and central
sleep apnea - Periodic limb movement disorder
-
Restless leg syndrome
