Module 5 - Non-Respiratory Sleep Disorders Flashcards
What are parasomnias?
Undesirable physical events or experiences that occur during, or entry to, or during arousals of sleep.
List 4 parasomnias
NREM Parasomnia
REM Sleep Behaviour Disorder
Recurrent Isolated Sleep Paralysis
Nightmare Disorder
What are some types of NREM parasomnias?
Include a wide variety of parasomnias, including confusional arousal, night terrors and sleep walking and sexsomnia
Why do NREM parasomnias occur?
May be due to ‘local’ sleep where 2 parts of the brain are in different sleep stages
When are NREM parasomnias more likely to occur?
Stress
Sleep deprivation
Alcohol
Depressive disorders
Describe what confusional arousals are (what they do to the body and when they are likely to occur).
A form of NREM parasomnia
Typically when waking out of N3 sleep.
If they occur in a sleep study, more likely to be severe at home.
They wake suddenly, increased HR, confused and incomplete awakening.
Generally not remembered
What is the incidence in age of confusional arousals?
3-4% above 15 years old
17% under 13 years old
Describe when night terrors are more likely to occur and what happens during a terror
Commonly occur in N3 sleep.
More common in kids, 3% or less of kids under 13 experience night terrors
Sudden waking with sleeping, increased HR and impossible to communicate with.
Why does sleep walking occur?
There’s a genetic influence, but not clear
What happens during sleep walking?
Difficult to arouse
Amnesia of event
Includes both routine and inappropriate behaviour
What percentage of adults who sleep walk also did it as a child?
60-70%
Only 10-20% of 4-8 year olds sleep walk
What is REM Sleep Behaviour Disorder?
Inhibition that is characteristic of REM sleep is disrupted, so movement with dreams can occur
Can result to harm to themselves or others as dreams are often violent.
People are unlikely to remember dream when awoken from episode
Who is more likely to experience REM sleep behaviour disorder?
Mainly in men over 50 years old
Common in people with, or who are developing Parkinson’s disease, Lewy Body disease and multiple systems atrophy.
~80% of people convert to PD
What are the prodromal behaviours of REM Sleep Behaviour Disorder?
May be sleep talking, limb jerking or vivid, violent dreams
What is the likely underlying neurologic problem of REM sleep behaviour disorder?
Issue with pons. May be responsible for reduced muscle tone.
Also potentially limbic system for violent dreams and/or striatum due to PD relationship
What can cause REM sleep behaviour disorder?
Withdrawal from REM suppressors like alcohol, substance abuse or withdrawal from other medication toxicity.
Associated with narcolepsy
Describe Recurrent Isolated Sleep Paralysis
Inability to move at sleep onset (hypnagogic) or on awakening (hypnopompic)
People have recall and are aware for event but being touched or spoken to or attempting to move can stop episode.
Sensation of dyspnea is common even though diaphragmatic function is in tact.
How frequently does recurrent isolated sleep paralysis occur?
Can occur several times a month, around 15-40% of students report having more than 1 episode.
More common in narcolepsy and idiopathic hypersomnia
What are triggers of Recurrent Isolated Sleep Paralysis?
Disrupted and irregular sleep
Sleep deprivation
Stress
What is the treatment of Recurrent Isolated Sleep Paralysis?
Often not needed
Describe what Nightmare Disorders are
Similar to dream anxiety attacks. Recurrent nightmares which are disturbing experiences.
Often occur during REM sleep and usually result in an awakening
Increased heart and respiratory wake before waking
When is Nightmare Disorder most common?
Following a trauma. Also involved in PTSD.
What is the epidemiology of Nightmare Disorder?
Adults: 50-80%
3-5 year olds: 10-50%
80% within 3 months of trauma in people with PTSD
What is the common treatment for Nightmare Disorder?
Image Rehearsal Therapy: write dreams with positive outcomes
List a hypersomnia
Narcolepsy
What is narcolepsy?
Disorder of sleep/wake instability.
Sleep is fragmented (short REM latency)
Unwanted sleep
Sleepiness is present
Hypnogogic hallucinations can occur
Describe the two types of narcolepsy
N1: excessive sleepiness, cataplexy, low or no orexin
N2: excessive sleepiness, no cataplexy, normal orexin
What is cataplexy?
When REM sleep intrudes wakefulness, which is commonly triggered by emotion.
Sudden loss of muscle tone.
What is the cause of cataplexy?
Unknown, in rare cases head trauma
What are hypnogogic hallucinations?
Seeing non-existent images at sleep onset
When is the onset of narcolepsy?
Usually between 20-30 years old
What type of test do you do for narcolepsy?
Multiple Sleep Latency Test
What result in a Multiple Sleep Latency Test would you expect to diagnose narcolepsy?
After PSG coming back normal…
MLST ≤ 8 minutes
≥2 SOREMPS in 5 naps (specific to Narcolepsy)
[sleep onset rem period]
What are the diagnostic needs for narcolepsy?
Stage 1:
- Excessive daytime sleepiness for 3 months or longer
- Cataplexy
- with PSG then MLST
Stage 2:
- Excessive daytime sleepiness for 3 months of longer
- No cataplexy
- wth PSG then MLST
What is hyposomnia?
Not getting as much sleep as you’d like.
What is a type of hyposomnia?
Insomnia
What are the 3 key features of insomnia?
Sleep complaint with
Adequate Opportunity
+ Daytime impairment
What types of difficulties in terms of sleep do people with insomnia have?
Perceived difficulty with:
- Sleep initiation
- Sleep consolidation
- Sleep duration
- Sleep quality
Despite opportunity with subsequent daytime impairment
How frequently does someone need to experience insomnia symptoms to be diagnosed?
≥ 3x a week
≥ 3 months
What other sleep disorders are commonly misdiagnosed as insomnia?
Circadian rhythm disorders
Sleep disordered breathing
Are there different types of insomnia?
3rd edition changed classification, so no longer primary and comorbid insomnia as differentiating the two was hard and treatment options were the same.
But, there are:
- Adjustment insomnia
- Pathophysiologic insomnia
- Paradoxical Insomnia (Sleep state misperception)
- Idiopathic insomnia
- Insomnia due to mental disorder
What is required to diagnose insomnia?
Sleep history
Sleep hygiene
Mental status at bedtime
Sleep/wake time
Daytime functioning
Medication history
Questionnaires like Epworth Sleepiness, BDI, PSQI
Actigraphy
PSG not common, but can be used to rule out OSA, PLMD or a parasomnia
What is a neurochemical feature of insomnia?
Decreased GABA
What is an adjustment (acute) insomnia?
Including prevalence and length of time.
In response to event, occurs for less than 3 months.
1 year prevalence: 15-20%
What is psychopathologic insomnia?
Including prevalence
Conditioned or learned insomnia, e.g. mental arousal in bedroom cues anxiety. Often slow onset of symptoms.
May underestimate sleep duration (not ‘gross’ like in paradoxical)
1-2% of general population but 12-15% in sleep centres. More common in women
What would you expect to see in sleep tests in psychopathologic insomnia?
Increased WASO
Increased latency
Decreased efficiency
MLST: 10-15 minutes
What is paradoxical insomnia (sleep state misperception)?
Including prevalence
Often report mismatched sleep quality and impairment.
May report no sleep but minimal dysfunction or similar level of dysfunction in other types of insomnia but is less severe than expected
<5% of insomnia
What do sleep tests reveal about paradoxical insomnia?
Sleep logs are inconsistent with objective evidence (PSG or actigraphy)
PSG:
- Reported latency and WASO is ≥ 1.5x PSG values
MSLT: normal or slightly reduced
What is idiopathic insomnia?
Including prevalence
Childhood onset, lifelong problems with sleep. No event started it.
<10% of insomnia, only 0.7% of adolescents
What would you expect to see in PSG for idiopathic insomnia?
Increased sleep latency
Increased WASO
Reduced total sleep time
Reduced sleep efficiency
What is insomnia due to mental disorder?
Including prevalence
Most common form. Often fixate on sleep and not on depressive symptoms.
More common in women than men, up to 3% of population
What would you expect to see on PSG and sleep logs for insomnia due to mental disorder?
Depression patients have short REM latency in PSG.
Logs have increased sleep latency and reduced total sleep time, early waking or frequent awakening
What is the pathway by which light impacts melatonin secretion?
Light ->
RHT ->
SCN ->
Superior cervical ganglia ->
Pineal gland ->
Melatonin -> SCN
When does DLMO occur?
~2-3 hours before typical bedtime
When does CBTmin occur?
Around 2 hours before waking
How can you estimate CBTmin from DLMO?
DLMO + 7 hours = CBTmin
When does melatonin midpoint occur in relation to CBTmin?
~2 hours before CBTmin
What can affect CBTmin?
Eating, activity and sleep
What can affect DLMO?
Posture and drugs
What is more effective at assessing phase changes? DLMO or CBTmin?
DLMO
When does exposure to light in relation to CBTmin cause a phase delay?
Before
After = phase advance
What type of light would be the most impactful to cause a phase change of CBTmin?
Outdoor light
Timing, duration and intensity
What is the relationship between melatonin and light phase response curves?
They are opposite but changeover may not happen at CBTmin
When would you take melatonin to cause the largest phase delay?
1-2 hours after spontaneous awakening
Several hours past CBTmin
What are the characteristics of a circadian rhythm sleep disorder?
Misalignment between endogenous and exogenous CR factors that affect…
Sleep timing
Sleep compliant
Daily impairment
How do you evaluate circadian rhythm sleep disorders?
Morningness/eveningness questionnaire: Lower values are evening types
Sleep logs
Actigraphy
What are the three types of circadian rhythm sleep disorders?
Delayed sleep phase
Advanced sleep phase
Shift-work type
What are the characteristics of a delayed sleep phase?
Inability to fall asleep at socially acceptable time. Cannot fall asleep earlier unless sleep deprived.
Would have normal sleep if they didn’t have to wake early
When is the onset of delayed sleep phase disorder?
~20 years old
What is the most common circadian rhythm sleep phase disorder? What is it’s prevalence?
Delayed
7-16% of adolescents and young adults in sleep clinics.
Around 10% of people with insomnia
What happens to DLMO and CBTmin in delayed sleep phase disorder?
DLMO delayed
CBTmin delayed
What is the treatment to delayed sleep phase disorder?
Chronotherapy
Morning light
Evening melatonin: 5-7 hours before habitual sleep onset
Use light AFTER CBTmin ~2 hours before waking.
What is the common genetic cause of delayed sleep phase disorder?
Clock gene problem
Family history
What is the prevalence of advanced sleep phase disorder?
Quite rare
Associated with ageing
~1% of middle aged population
1:1 M and W
What is the common genetic cause of advanced sleep phase disorder?
Mutation in hPer2 clock gene
What would the morningness and eveningness questionnaire look like for an advanced sleep phase disorder?
High score, morning type
What is the treatment for advanced sleep phase disorder?
Bright light in the evening but problems with compliance
What is required to be diagnosed with shift-work type circadian rhythm disorder?
> 1 month long of excessive daytime sleepiness associated with recurrent work schedule that overlaps with sleep
