Lecture 13: Sleep Medicine Part II, Neurologic Sleep Disorders Flashcards
What are the 3 cardinal symptoms of patients presenting to a sleep clinic?
- Excessive sleepiness
- Insomnia
- Nocturnal movement or behaviors
What is Excessive Sleepiness?
“I can’t stay awake”
What are the DDx for excessive sleepiness?
- NARCOLEPSY
- Sleep apnea
- Insufficient sleep
- Medication effect
What is insomnia?
“I can’t sleep or stay asleep”
What are the DDx for insomnia?
- Mood disturbance
- Circadian Rhythm Disturbance
Delayed-sleep phase = night owls - RESTLESS Legs/Periodic Limb Movement of Sleep
What are examples of Nocturnal movements or behaviors?
“I do [or feel] unusual things at night”
What are DDx for unsual movements or behaviors
- PARASOMNIA emerging from REM or non-REM
- Nocturnal Seizure
- Movement Disorder
What are the clinical tools to measure sleep disorder?
Polysomnography = sleep monitoring
Sleep logs
Actigraphy = looks like a wrist watch and measures motion
Lab assessment, physical exam, detailed history
What are the cardinal symptoms of Narcolepsy? Known as “The Tetrad”
- Hypersomnolence
- excessive daytime sleepiness and involuntary dozing-
- Cataplexy
- brief moments of weakness triggered by EMOTION like laughter, anger or surprise
- Hypnogogic/hypnopompic hallucinations
- vivid dreams
- Sleep paralysis
- loss of muscle tone when you wake up/are about to fall asleep
- Sleep quality is also often impaired
If someone goes into REM sleep in two naps during the day, she or he has
Narcolepsy
What is a delineating factor of narcolepsy?
Boundaries between wakefulness and REM sleep are not well-maintained
Sleep architecture is disrupted across the 24 hour period
-mean sleep latency = 2.3 minutes
-REM sleep in 3 of 4 naps (shouldn’t be going into REM during naps)
-Sleep paralysis in nap 2
What is cataplexy?
- Sudden loss of muscle tone
- Triggered by emotion, especially laughter
- Consciousness spared
What is the epidemiology of narcolepsy?
USA = .05% prevalence
Presents in 2nd to 4th decade with bimodal distribution
What is the pathophysiology of narcolepsy?
Hypocretinergic neurons from postero lateral hypothalamus project widely to areas of brain involved in sleep-wake control
-hypocretin is diminished or ABSENT in narcolepsy with cataplexy
What is Hypocretin (orexin)?
A neuropeptide produced in the posterolateral hypothalamus
- hypocretinergic neurons project widely to areas of brain involved in sleep-wake control
- decerased/absent in narcoleptic patients
What is the Flip-flop switch model?
AWAKE: orexin stimulates Locus coeruleus, TMN (tuberomammillary nucleus) and raphe nuclei; inhibits VLPO
Sleep: VLPO inhibits orexin and LC, TMN, raphe nuclei; VLPO induces sleep
What is VLPO? Location?
VentroLateral Preoptic Nucleus
Located in the hypothalamus
What are the three states of wakefulness? Significance?
- REM sleep
- non REM sleep
- Awake
Significance: symptoms of several sleep disorders including narcolepsy can be modeled as an overlap between sleep-wake states
Example: narcolepsy = Wake/REM combinations
Is hypocretin used as a diagnostic tool for narcolepsy?
No (Cat)
What is the treatment for narcolepsy?
- Hypersomnolence
-stimulants
-modafinil/armodafinil (Provigil)
-naps - Cataplexy
-Tricyclic antidepressants
-SSRIs
-gammy hydroxybutyrate (Xyrem…date rape)
Stimulant + sedatives??
What is one characteristic of Narcolepsy?
Is associated with decreased brain hypocretin level
What is parasomnia?
An undesirable behavioral, motor or sensory phenomenon which occurs intermittently during sleep
-some parasomnias may be considered normal like nightmares
-can emerge from REM or REM sleep
-people don’t remember it
Symptom that is an intersection of Wake, REM and non-REM
Example: sleep walking and doing shit like getting arrested for urinating in a dorm hallway while in sleep
When someone displays behavioral/motor/sensory phenomenon during sleep, to what extent can another person reach that sleeper?
No, the person who is acting out dreams does not respond to external stimuli (unless stimuli is enough to awaken him or her)
What are types of normal parasomnia?
- Sleep-talking
2. Nightmares
Patients who sleepwalk
Typically have minimal recall of their episodes the following day
What percentage of adults sleepwalk? Sleep terrors?
1-2%
15-30% of children (once)
Jennifer Anniston lol
Sleep terrors – 1-6%, peaks at 5-7
What are disorders of arousal or abnormal parasomnia?
- Confusional arousals
- Sleepwalking
- Sleep terrors
- sympathetic response and is unaware of external stimuli
What are the key characteristics of disorders of arousal?
Origin in non-REM (slow wave) sleep
Lack of recall
Positive family history common
How do you treat sleep walking?
- Reassurance, secure environment
- Warning device
- Avoid shit like ETOH, stresss or insufficient sleep
- Benzodiazepines
Patients who sleep walk
typically have minimal recall of their episodes the following day
What is REM sleep behavior disorder?
A dissociated state characterized by
-violent dream-enacting behavior by history or polysomnogram
-increasing tonic or phasic EMG in REM sleep
-absence of epileptiform activity
Presents with resting tremor!
What is the etiology of REM sleep behavior disorder?
Idiopathic Narcolepsy Overlap with non-REM parasomnia Neurodegenerative disease Medications Disrupted REM sleep
What is epidemiology of chronic RBD?
87% MALE
Mean age = 52 years
Prodrome in 25% at 22 years
What are comorbidities of RBD?
- parkinson’s
- Lewy Body Dementia
- multi-system atrophy
How do you treat RBD?
- Clonazepam (90% effective)
- Melatonin
- secure environment
What is sleep apnea?
A sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing during sleep
RBD typically presents
in patients in their fifties and sixties
What are Restless legs?
n AWAKE sensory phenomenon with a volitional (voluntary) motor response
What are Periodic limb movements?
An INVOLUNTARY SLEEP-related motor phenomenon
How do you diagnose RLS?
URGE Urge to move the legs usually with dysesthesias -Dysesthesias: abnormal sensation Onset with Rest or inactivity Getting up = relief with movement Evening = time of day when it is worse
What is epidemiology of RLS?
6-15% of adults
Prevalence increases with age
Early onset RLS more likely idiopathic/familial
Late onset = secondary and more rapidly progressive
What causes secondary RLS? Exacerbating factors?
- Iron deficient anemia
- Pregnancy
- Chronic renal failure
Caffeine, poor sleep, stress can exacerbate RLS
What is the pathophysiology of RLS?
Thought to be
Impaired central dopaminergic transmission
May be caused by less iron in brain
Funcitonal expression of the impairment appears to be reduced supra-spinal inhibition
What is the link between restless leg syndrome and periodic limb movement?
Both may represent state-dependent reduction of supra-spinal inhibition
Affecting sensory afferents = RLS
Affecting motor efferents = PLM
RLS does not necessarily have to correlate with PLMS because a lot of PLMS patients don’t have RLS…although 80% of RLS patients have periodic limb movement
What is the treatment for RLS?
Dopamine agonists Opiates Gabapentin Iron Benzodiazepines
RLS is best characterized as?
an urge to move legs which is temporarily relieved with movement
When you see a patient with RLS, what blood tests should order?
Look at their iron levels!
Low iron levels could precipitate RLS
