Insomnia is defined as the inability to fall asleep and or stay asleep, early morning awakening or non- refreshing sleep lasting for at least one month and is associated with functional impairment. 

Insomnia can be classified according to its duration to transient, acute and chronic types.

  1. Transient insomnia lasts from days to weeks. It can be caused by another disorder, by changes in the sleep environment, by the timing of sleep, severe depression, or by stress.
  1. Acute insomnia is the inability to consistently sleep well for a period of between three weeks to six months.
  1. Chronic insomnia lasts for more than six months to years at a time.


Insomnia can be a primary disorder or it can be caused by another medical condition. These causes may be divided into situational factors, medical or psychiatric conditions, or other sleep problems.
Some of the causes are as follows:

Situational and life-style factors:

  • Jet lag
  • Changes in shift work
  • Uncomfortable room environment
  • Insomnia related to high altitude (mountains)

Psychological and behavioral factors:

  • Stressful life -situations and events (exam preparation, loss of a loved one, unemployment, divorce, or separation)
  • Sleep state misperception, in which the patient has a feeling of not sleeping adequately, but there are no objective (polysomnographic or actigraphic) findings of any sleep disturbance
  • Inadequate sleep hygiene
  • ADHD

Psychiatric conditions:

  • Depression
  • Anxiety, stress
  • Bipolar disorder
  • Psychotic disorder
  • Alcohol and drug abuse

Medical conditions:

  • Presence of an acute medical or surgical illness or hospitalization
  • Withdrawal from drug, alcohol, sedative, or stimulant medications
  • Chronic pain syndrome
  • Fibromyalgia
  • Heart disease
  • Asthma
  • COPD
  • Degenerative diseases, such as Parkinson's disease and Alzheimer's disease
  • Brain tumors, strokes or trauma to the brain
  • Certain medications

Other, specific sleep conditions:

  • Circadian rhythm disorder
  • Sleep Apnea
  • Restless leg syndrome
  • Periodic limb movement disorder


The first-line recommended treatment is cognitive behavioural therapy for insomnia, available at Sleep on the Bay.

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