Insomnia Disorder

Insomnia Disorder is the dissatisfaction with sleep quantity or quality, with complaints of difficulty initiating or maintaining sleep. Put simply, insomnia is defined as difficulty falling asleep or staying asleep, even when a person has the chance to do so. Insomnia also involves daytime impairments (fatigue and daytime sleepiness). Other changes include cognitive impairment (impacts on attention, concentration, and memory), and mood changes (irritability, mood lability). Insomnia disorder often causes clinically significant distress and/or impairment in social, occupational, or other areas of functioning. It can occur during the course of another mental disorder or medical condition, or it may occur independently.

  • Insomnia disorder is the most prevalent of all sleep disorders
    • About 30% of the general population have insomnia symptoms and 10% have an associated functional daytime impairment
    • Up to 10% have symptoms that meet criteria for insomnia disorder.
Risk Factors
  • Older age, women (more prevalent among females than males), widowed, lower socioeconomic status, smokers, drinkers, and with co-morbid psychiatric and medical conditions. Close to 50% of individuals with psychosis experience insomnia, and this is predictive of the onset of psychotic experiences.[1]
  • Disrupted sleep and insomnia also have a familial disposition. Insomnia is higher in monozygotic twins compared to dizygotic twins; it is also higher in first-degree family members.
  • Poor sleep hygiene, irregular sleep scheduling, and the fear of not sleeping also exacerbate symptoms
  • Noise, light, uncomfortably high or low temperature, and high altitude may also increase vulnerability to insomnia.
Criterion A

A predominant complaint of dissatisfaction with sleep quantity or quality, associated with 1 (or more) of the following symptoms:

  1. Difficulty initiating sleep.
    In children, this may manifest as difficulty initiating sleep without caregiver intervention
  2. Difficulty maintaining sleep, characterized by frequent awakenings or problems returning to sleep after awakenings.
    In children, this may manifest as difficulty returning to sleep without caregiver intervention
  3. Early-morning awakening with inability to return to sleep.
Criterion B

The sleep disturbance causes clinically significant distress or impairment in social, occupational, educational, academic, behavioural, or other important areas of functioning.

Criterion C

The sleep difficulty occurs at least 3 nights per week.

Criterion D

The sleep difficulty is present for at least 3 months.

Criterion E

The sleep difficulty occurs despite adequate opportunity for sleep.

Criterion F

The insomnia is not better explained by and does not occur exclusively during the course of another sleep-wake disorder (e.g., narcolepsy, a breathing-related sleep disorder, a circadian rhythm sleep-wake disorder, a parasomnia).

Criterion G

The insomnia is not attributable to the physiological effects of a substance (e.g., a drug of abuse, a medication).

Criterion H

Coexisting mental disorders and medical conditions do not adequately explain the pre-dominant complaint of insomnia.



Specify if:

  • With non-sleep disorder mental comorbidity, including substance use disorders
  • With other medical comorbidity
  • With other sleep disorder

Duration Specifier

Specify if:

  • Episodic: Symptoms last at least 1 month but less than 3 months.
  • Persistent: Symptoms last 3 months or longer.
  • Recurrent: Two (or more) episodes within the space of 1 year.

Types of Insomnia

Type Description
Sleep-onset Insomnia (Initial Insomnia) Difficulty initiating sleep at bedtime. Defined by a subjective sleep latency greater than 20-30 minutes.
Sleep Maintenance Insomnia (Middle Insomnia) Frequent or prolonged awakenings throughout the night. Defined by subjective time awake after sleep onset greater than 20-30 minutes
Late Insomnia Early-morning awakening with an inability to return to sleep.
Early-morning Awakening Awakening at least 30 minutes before the scheduled time and before total sleep time reaches 6.5 hours.
Non-restorative Sleep Poor sleep quality that does not leave the individual rested upon awakening despite adequate duration. This is a common sleep complaint usually occurring in association with difficulty initiating or maintaining sleep, or less frequently in isolation.

Behavioural insomnia is the most common type of insomnia in the pediatric population (i.e. - bedtime problems and/or awakenings, or “bed time resistance”). Children may refuse to sleep, want to be rocked, or sleep in their parents’ bed. This “flocking” behaviour is common in all mammals and a natural protective instinct. Popular methods that demand that children “cry it out” can actually impede development of healthy self-regulation.[2] Soothing with an aim toward learning self-soothing provides better long-term results for emotional growth and resilience. Behavioural insomnia should not be treated pharmacologically!

The 3 principles to treating bedtime resistance are:

  1. Creating an emotional state of calmness and safety
  2. Consistent limit setting
  3. Establishing good bedtime habits (i.e. - have a wind-down 
period and a sequence of activities that begin 30 to 60 minutes before bedtime, and promote sleep hygiene).

The onset of insomnia symptoms can occur at any time during life, but the first episode is more common in young adulthood. Less frequently, insomnia begins in childhood or adolescence. Insomnia disorder is considered to be due to hyper-arousal during the day (all-day hyper-vigilance) with difficulty initiating/maintaining sleep during the night. There are several models that attempt to explain insomnia, including: (1) the cognitive model, (2) the physiologic model, and (3) the neuroendocrine model.


Insomnia can also be situational, persistent, or recurrent. Situational or acute insomnia usually lasts a few days or a few weeks and is often associated with life events or rapid changes in sleep schedules or environment. It usually resolves once the initial precipitating event subsides.

A detailed evaluation is important to understand the cause and nature of the insomnia, this includes:

  • Physical examination
  • Past and present psychiatric history
  • Medication use
  • Alcohol, drug, and caffeine use
  • Sleeping habits
  • Sleep partner’s report
  • Questionnaires and sleep diary

Measuring sleep quality can be done through scales, questionnaires, and sleep diaries:

Measurement Scales for Sleep Quality

Name Rater Description Download
Epworth Sleepiness Scale (ESS) Patient The ESS is a self-administered questionnaire with 8 questions. ESS Information
Insomnia Severity Index (ISI) Patient The ISI has seven questions rated on a scale of 0 to 4.[4] ISI Download
Pittsburgh Sleep Quality Index (PSQI) Patient The PSQI is an effective instrument used to measure the quality and patterns of sleep in adults. It differentiates “poor” from “good” sleep quality by measuring 7 components. PSQI Download

Polysomnography usually shows impairments of sleep continuity (e.g., increased sleep latency and time awake after sleep onset and decreased sleep efficiency (percentage of time in bed asleep) and may show increased stage 1 sleep and decreased stages 3 and 4 sleep. The severity of these sleep impairments does not always match the individual's clinical presentation or subjective complaint of poor sleep, as individuals with insomnia often underestimate sleep duration and overestimate wakefulness relative to polysomnography.

Quantitative electroencephalographic (EEG) analyses may indicate that individuals with insomnia have greater high-frequency EEG power relative to good sleepers both around the sleep onset period and during non-rapid eye movement sleep, a feature suggestive of increased cortical arousal. Individuals with insomnia disorder may have a lower sleep propensity and typically do not show increased daytime sleepiness on objective sleep laboratory measures compared with individuals without sleep disorders.

Other laboratory measures show evidence, although not consistently, of increased arousal and a generalized activation of the hypothalamic-pituitary-adrenal axis (e.g., in creased cortisol levels, heart rate variability, reactivity to stress, metabolic rate). In general, findings are consistent with the hypothesis that increased physiological and cognitive arousal plays a significant role in insomnia disorder.

Sleep hygiene implementation and sleep education should be a first step for patients reporting insomnia. Basic sleep hygiene alone has not been shown to be effective in treating chronic insomnia, but is important for patient education.[5][6][7] It is important to keep at these habits for at least 2 to 3 weeks before giving up and trying more aggressive interventions such as CBT-I and/or hypnotics. Key sleep hygiene practices include:

  1. Keep Your Bedroom Cool, and Dark: A dark room reminds your brain it is nighttime, and a cool room temperature allows your body thermoregulate during sleep.
  2. Get Regular Sleep: Make sure your sleep schedule is regular. Wake up the same time every day and go to sleep the same time every day. This includes the weekdays and weekends.[8]
  3. No Napping: Do not nap at all during the day. This includes lying down! It is important to associate a horizontal body position with sleeping.
  4. No Stimulants: No caffeine or smoking (at least 8 hours before bed)[9]
  5. No Alcohol: Although individuals may find that it helps them relax and fall asleep easier, alcohol worsens sleep quality, and suppresses REM sleep.[10][11][12]
  6. No Electronics Before Bed: Do not watch televisions, use your phone, or a computer for at least 1 hour before bed. The blue light stimulates the brain to think it's daytime again.
  7. Have A Bedtime Routine: Set a bedtime routine before going to bed (i.e. - 30 minutes before sleeping, turn off all electronics, listen to soothing music, and read a book in a dim light)
  8. Wind Down: Make sure you are winding down at least 1 hour before bed, and avoid doing stimulating activities
  9. Only Sleep When You Are Sleepy: Do not go to bed until you are actually feeling sleepy
  10. Don't Lie Down During the Day: You want to associate a horizontal body position only with sleeping.
  11. Environment: Make sure the room is quiet, not too bright, and at the right temperature (not too warm or cold)
  12. Bed For Sex and Sleep Only: Do not read books, use your phone, or use a computer on the bed. It is important to associate the bed with sleep (and sex if applicable…) and not any other activities.
  13. Don't Look At The Clock: Avoid the temptation to peek at the clock!
  14. Don't Use The Snooze Button: Snoozing results in short-term gain with long-term (bad) consequences. Snoozing can worsen sleep the day after.
  15. Exercise: Regular exercise can promote good sleep quality.[13] It was previously believed that exercising in the hours leading up to sleep would impair sleep quality, though current evidence suggests this does not make a difference.[14]
  16. Keep a Sleep Diary: A sleep diary can help make sure you know exactly when you sleep and wake up, and help direct the right changes.
  • CBT for Insomnia (CBT-I) is an effective and cost-effective treatment for insomnia disorder and should be offered as a first-line treatment.[15][16]
  • Components of CBT-I include: sleep hygiene education, sleep restriction, stimulus control therapy, relaxation-based interventions (e.g. - progressive muscle relaxation), and cognitive restructuring.
  • Research evidence has also shown that CBT-I should be a first-line treatment for insomnia in mid-life women experiencing menopause with hot flashes.[17] With the advent of the internet, CBT-I has become widely accessible online (see table below).
  • There is strong and robust evidence that shows the effectiveness of CBT-I for insomnia.[18]
  • Importantly, there is comparable treatment effect with hypnotics, and the effects from CBT-I are more durable than medications.[19]
  • CBT-I can also reduce and eliminate the need for hypnotic use.
  • CBT-I can also significantly reduce depression symptoms.[20]
Recommended Reading

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Online Insomnia Therapies

Name Description Cost
CBT for Insomnia 5-session on-line cognitive behavioural therapy (CBT) program for insomnia. $24.95 US to $49.95 US
CBT-i Coach Structured program that teaches strategies to improve sleep and help alleviate symptoms of insomnia. Free
Sleepio Evidence-based CBT-I online and mobile app program $300 US for a 12-month subscription
SlumberPRO Self-help program from Queensland Australia, requires 30-60 minutes each day and program lasts 4-8 weeks $39 AUS
Go! To Sleep 6-week CBT-I program (and mobile app) available through Cleveland Clinic of Wellness $3.99 US for app, or $40 US for web
SHUTi 6-week CBT-I program, evaluated in 2 randomized trials involving adults with insomnia and cancer survivors $135 US for 16 weeks access, or $156 US for 20 weeks access
Restore CBT-I A 6-week CBT-I program evaluated in a randomized trial £99 to £199
Sleep Training System 6-week on-line CBT-I program with money-back guarantee and personalized feedback $29.95 US

Based on American Academy of Sleep Medicine Guidelines[21] and College of Physicians and Surgeons of Alberta Guidlines.[22]

Pharmacological Treatment of Insomnia

1st Line Benzodiazepine-receptor agonists: Temazepam (US FDA Approval: Estazolam, flurazepam, quazepam, triazolam*)
Non-Benzodiazepine-receptor agonists: Zopiclone, zolpidem, eszopiclone, zaleplon
2nd Line Sedating antidepressants: Trazodone, doxepin, mirtazapine and other sedating SSRIs
Off-label Antipsychotics: Olanzapine, quetiapine and risperidone are used in clinical practice
Supplements: Melatonin, tryptophan and valerian root
Anticonvulsants: Gabapentin, pregabalin
  • When taking melatonin, it is recommended to take it 6 hours before the middle of sleep (i.e. - if you sleep 8 hours, then take melatonin 2 hours before your typical sleep time).

Benzodiazapine as sleep aids

Although triazolam is FDA-approved for insomnia disorder, it should really not be used given its short half-life and therefore high potential for addiction, misuse, and withdrawal symptoms. Tamazepam or clonazepam would be better choices if you absolutely have to use a benzodiazapine.

Don't forget!

Short-term hypnotic treatment should always be supplemented with behavioural and cognitive therapies if possible.

If you are at all considering antipsychotics (which you really should not), you must consider the following: weight gain and therefore worsening of sleep apnea, increased leg restlessness, hyperlipidemia, glucose dysregulation, and QT prolongation. All these reasons should make you think twice about prescribing antipsychotics for sleep. For this reason alone, the NIH Chronic insomnia panel states: “all (antipsychotics) agents have significant risks, and thus their use in the treatment of chronic insomnia cannot be recommended.”