WK 8 - Sleep disorders

Sleep definition

An essential and naturally recurring state of mind and body, characterised by altered, reduced, consciousness, relatively inhibited sensory activity and reduced muscle activity

• A series of highly orchestrated events puts the brain to sleep in stages:

  • Stage 1

light sleep, may have awareness of surrounding, only 5-10 mins

• A series of highly orchestrated events puts the brain to sleep in stages:

  • Stage 2

50% of the night so bulk of sleeping time, more stable sleep occurs, lower frequency and higher amplitude brain waves, muscles become more relaxes, chemicals produced in the brain blocking the senses making it difficult to be woken

• A series of highly orchestrated events puts the brain to sleep in stages:

  • Stage 3

deep sleep, growth hormone released, Most stage 3 occurs in the first third of the night, 60-90 minutes in the night for younger adult and may drop to 30 minutes or less for older adults

• A series of highly orchestrated events puts the brain to sleep in stages:

  • REM sleep

eyeballs dilating back and forth under eyelids, muscle twitches, absent of voluntary movement, brain activity is very high and intense, brain paralyses the muscles to make sure we don’t act out our dreams, dreams are very important implicated in supporting memory and emotional processing, most vivid dreams occur - can dream in other stages of sleep, may wake up briefly

Different types of sleep at differen types of night

• Deep sleep at the beginning of the night and REM sleep towards the end of the night

Functions of sleep

• Growth & repair

• Immune function

• Heart health

• Brain health

• Memory

• Learning

• Concentration

• Energy

• Stress management

• Psychological health

• Physical stamina

• Mood regulation

 

Why is sleep good for the brain?

• When our brain is busy operating during the day the cells create waste product

• Glymphatic system - sleep washes away the toxins so we don’t get plaques building up in the brain which can impact brain function

Relationship between sleep, mood & psychopathology

• There is a very strong relationship between sleep and mental health

  • For a long time it was assumed poor mental health caused poor sleep

  • But poor sleep may be a bigger impact on mental health

When we are not well slept the ____________ do not communicate well…

prefrontal cortex and amydala. The prefrontal cortex calms down the amygdala which processes emotion

Two types of sleep disorders

• dyssomnias (sleep quantity, quality and timing)

• parasomnias (unusual behaviours during sleep)

• dyssomnias (sleep quantity, quality and timing) - 4 types

insomnia disorder, hypersomnolence disorders, breathing related sleep disorders, circadian rhythm disorders

• parasomnias (unusual behaviours during sleep)

nightmare disorder, REM behaviour disorder, NREM arousal disorders

NREM arousal disorders

• Incomplete awakenings from deep sleep that involve motor movements - sleep walking, talking, eating, sex

What stage of sleep does NREM arousal disorders occur?

• Difficulty occurring in other stages of sleep other than REM

• Most often occur in the first third of the night

Occurence of NREM arousal disorders

• Often triggered by an external stimulus which elicits a partial wakening

• Occurrence likely explained by a stress-diathesis model

  • Increased occurrence with sleep deprivation, stress & certain substances in vulnerable individuals

NREM arousal disorders

• Genetic link

• Develops in _____

• More common in…

• childhood

• children (10% vs 1-2% in adults, although occasional episodes are more common)

What is happening in the brain in NREM arousal disorders?

• not acting as a whole and different parts of the brain are simultaneously existing in different states

  • The brain acts desynchronously between the stages of sleep

  • One part of the brain is remaining in a wake like stage while the other parts of the brain might remain in a sleep like stage

Is there a memory for the episode in NREM arousal disorders?

No

Sleep terrors

• Frightening experiences during deep sleep

• May be accompanied by screaming, walking, sitting up

• Sleeper is difficult to rouse

• Often triggered by sleep deprivation

• The advice is not to wake the sleeper up and let the episode run its course

• If awoken, the individual is confused and disoriented

Treating NREM arousal disorders

• Often no treatment is required if the episodes are occasional but treatment may be provided if it impacts sleep badly

If treatment is required for NREM arousal disorders then…

• Psychoeducation & advice

• Don’t try to wake individual - make environment safe, calm and offer comfort if wanted

• Medications usually first line treatment

  • Melatonin usually used first

• Good sleep hygiene and avoiding sleep deprivation can reduce likelihood of an episode

• Stress management

• Scheduled awakening may help

REM parasomnias - REM behaviour disorder

• Movement/vocalisation that occurs during REM

REM parasomnias - REM behaviour disorder

• Movements are often uncoordinated and aimless:

• Thrashing about

• Unintelligible speech, screaming, yelling, singing

• Less interaction with the external world

• Uncommon to get completely out of bed

REM parasomnias - REM behaviour disorder - why does these movements happen?

Mechanism of muscle atonia in REM sleep goes away

REM parasomnias - REM behaviour disorder prevalence

• Less than 1% of adults

• More common in men and over age 50

REM parasomnias - nightmare disorder

• Disturbing, vivid dreams that awaken the sleeper

• Person wakes alert, oriented with clear recall of the dream

• Awakening following nightmare can be lengthy

• Can make going to bed very scary

REM parasomnias - nightmare disorder criteria

3+ times a week, plus distress and impair

REM parasomnias - nightmare disorder prevalence

• 4% prevalence in adults (up to 30% experience regular nightmares and 70% have had at least one)

• Up to 50% of children have regular nightmares

• More common with psychological diagnoses

REM parasomnias - nightmare disorder treatments

• Medication (prazosin)

• IRT (form of CBT)

What is IRT for chronic nightmares based on notion of?

 that nightmares can become habitual (don’t want to go to sleep because fearful)

First 3 stages of IRT for chronic nightmares

1. Build relaxation/imagery/coping skills

2. Select nightmare to work on (graded)

3. Write description of the start of the nightmare

Stage 4 for IRT for chronic nightmares

1. Select a way to change the nightmare

   1. Increase sense of control

   2. The change occurs before the traumatic event

   3. Can be fanciful - putting on slippers, wings etc.

Stage 5-7 for IRT for chronic nightmares

1. Write the nightmare with the change

2. Rehearse the dream with the change plus relaxation

3. Rehearsal before bed

Hypersomnolence disorder

• Epworth sleepiness scale

• The individual rates how likelihood they would be to fall asleep in different scenarios

• Can be scored up to 5 and be classed as normal daytime sleepiness

• Scores above 13 is a level of sleepiness that is impacting the persons quality of life

Narcolepsy

neurological disorder of excessive daytime sleepiness. recurrent episodes of irrepressible need to sleep, occruing within the same day

Narcolepsy prevalence

Uncommon - 1 in 2000

equal across males and females

How long does narcolepsy have to occur for?

at least three times per week for 3 months

Type 1 narcolepsy presence of

• episodes of cataplexy occuring at least a few times per month

• disturbed night-time sleep

• sleep paralysis and hypnogogic hallucinations

• PSG defined reduced REM latency

How is narcolepsy diagnosed?

in the lab using MSLT (multiple sleep latency test)

What is the emerging veiw of narcolepsy?

a disorder of unstable sleep and wakefulness. There are unstable boundaries between wakefulness, REM sleep ad sleep in general

What is narcolepsy caused by?

lack of orexin

First line treatment for narcolepsy

stimulant or wake promoting medications: eg modafinil

Behavioural strategies cannot replace orexin but they may reduce additional sources of instability within the sleep wake system:

• Improve night time sleep

• Reduce additional sources of sleep-wake instability

• Become aware of triggers for sleep attacks

• Planned and strategic napping

• Emotion regulation

Idiopathic hypersomnia

• Like narcolepsy, the individual experiences excessive daytime sleepiness ( 3 months +)

• Sleepy and lethargic despite normal (7hr) or greater than normal night-time sleep duration

• Naps tends to be unrefreshing (sleep inertia - feel half asleep when awoken)

• Night time sleep is often long duration

• No or fewer SOREM episodes

Obstructive sleep apnea - airway?

• Airway is blocked and air does not move through

• Airway is too narrow or collapses

Obstructive sleep apnea - what does this blocked airway result in?

• Reductions in blood oxygen levels (desaturation) are recorded during polysomnography

• Typical blood oxygen level (saturation) = 96%-97%. <80% = severe

more on Obstructive sleep apnea

• Frequent wake ups

• Untreated OSA = contributing factor for accidents, depression, cardiovascular disease and metabolic disease

• Screening: Stop-bang or berlin

Obstructive sleep apnea diagnosis

• PSG evidence of 5 or more obstructive apneas (stoppage) or hypopneas (reduction) per hour. Plus

  • Snoring, gasping, snoring, breathing pauses

  • Daytime sleepiness, fatuigue or unrefreshing sleep

• PSG evidence of 50 ore more apneas/hypopnea events per hour of sleep regardless of daytime symptoms

Obstructive sleep apnea prevalence

• mild: 30% Mod-sev: 10% women, 20% men

• More common with high BP

• More common if overweight

• Exacerbated by alcohol use

• Sex differences even out somewhat after menopause

What is the first line treatment for obstructive sleep apnea?

CPAP - hose that delivers stream of air to keep the airway open

Role of behavioural sleep medicine in OSA

• To get people to continue to use CPAP

• Motivational interviewing (miller & Rollnick)

  • Understand why treating the OSA is important for the individual

  • Cultivate willingness to work with CPAP difficulties

• Graduated exposure to CPAP therapy

• Support for weight loss

Insomnia disorder

1. Dissatisfaction with sleep quantity or quality - different types?

• Falling asleep (onset insomnia)

• Maintaining sleep (frequent or long awakenings) (maintenance insomnia)

• Early morning awakenings with inability to return to sleep (late insomnia)

• Combination of the above (mixed insomnia)

Insomnia disorder diagnosis requires

• At least 3 nights per week

• Episodic: 1-3 months

• Persistent: present for at least 3 months

• Occurs despite adequate opportunity for sleep

Insomnia disorder prevalence

• 30% have insomnia symptoms

• 10% meet diagnostic criteria

• More common in women than in men (nearly 2:1)

• Prevalence increases with age in both sexes

• Prevalence increases with chronic illness (cancer 50%), sleep disorders, stress, psychiatric conditions, menopause, shift work

• 75% of insomnia cases will have a comorbidity

• Insomnia affects anywhere from 50-80% of the treatment-seeking psychiatric population (depression most common)

Untreated insomnia (Freeman et al., 2020)

• Impaired quality of life

• Reduced job performance/increased absenteeism & vastly increasd healthcare usage

• increases risk for the development of a depressive disorder, substance misuses, anxiety disorder, mania

• This effect is even more pronounced for relapses of depression where in 56.2% of cass, insomnia symptoms preceded symptoms of a mood disorder relapse

Treated comorbid insomnia

• Depressed patients successfully treated with CBT-I experience improvement in dperession and a more rapid antidepressant response. Also effective in psychosis and anxiety disorders

Insomnia is the most common…

symptom listed in the DSM-5 for disorders

Bidirectional effects of insomnia

insomnia and many co-existing conditions

Insomnia can contribute to allostatic overload

disrupting neuroplasticity and stress-regulation pathways

What is the most common treatment for insomnia?

• 95% with symptoms are given medication

• But CBT-I is recommended as first line treatment by research

CBT-I potential for improvement

75% of people with even long term insomnia obtain lasting benefit and evidence that CBT is more effective than medication in the long-term

perpetuating factors for insomnia

excessive time in bed, napping, conditioning

Insomnia cycle

Trigger → thoughts/beliefs → emotions/arousal → behaviour → consequences

Dsyfunctional beliefs about sleep scale

• if these beliefs can be shifted then insomnia is more likely to be improved. They hold negative automatic thoughts

• A person who believes they cannot function without 8 hours sleep is more likely to be impacted by insomnia