Central Disorders of Hypersomnolence Flashcards
What are 6 core features of narcolepsy?
- EDS
- Cataplexy
- Sleep paralysis
- Hypnogogic/pompic hallucinations
- Fragmented sleep
- Automatic behavior
What is the definition of a SOREMP?
REM sleep within 15 minutes of sleep onset
What are the PSG and MSLT criteria for a diagnosis of narcolepsy?
- Mean sleep latency of 8 minutes or less
- 2 SOREMP in the MSLT
- 1 SOREMP in the PSG and 1 SOREMP in the MSLT
What percent of narcolepsy patients have cataplexy?
At least 60%
Which has a deficiency of orexin, Type I (with cataplexy) or Type II (without cataplexy)?
Type I
What level of CSF hypocretin (orexin) is diagnostic for Type I Narcolepsy?
< 110 pg/mL
What is the most effective treatment for cataplexy, inhibition of reuptake of NE, serotonin or dopamine?
NE
If a patient can’t take sodium oxybate for cataplexy, what could be given qhs instead?
Clomipramine 25 to 75 mg qhs
(TCA)
TCAs interact with what receptors
- Serotonin
- Acetylcholine
- NE
- Histamine
They DON’T interact with dopamine
Conditions that can cause secondary narcolepsy with low hypocretin levels (6)
- MS
- Prader-Willi syndrome
- Myotonic dystrophy
- AD cerebellar ataxia
- TBI
- Mass lesion in hypothalamus
Positive HLA-DQB1*0602 is found in what % of the population without narcolepsy?
25%
3 medicines for cataplexy
- Sodium oxybate
- Venlafaxine
- Clomipramine
MSLT or Actigraphy diagnostic criteria for Idiopathic Hypersomnia
MSLT = 8 min with 1 or no REM periods
or
At least 660 min of sleep over a 24 hour period
At what age does Klein-Levin Syndrome typically occur?
Teenage years
How long does each episode of Klein-Levin Syndrome typically last?
Days to a few weeks
How many episodes in Klein-Levin Syndrome will occur each year?
1 to 10 typically
What unusual symptoms typically occur in Klein-Levin Syndrome?
- Hyperphagia
- Hypersexuality
- Abnormal behavior: Confusion, irritability, aggression and hallucinations
In Klein-Levin Syndrome how long do the daytime sleep episodes last?
Up to 18 hours per 24
How long does Klein-Levin Syndrome last in total?
1 to several years with an average of 4
What medication can make Klein-Levin Syndrome worse?
Daytime stimulants can cause psychiatric symptoms
What 4 medications have show some benefits for Klein-Levin Syndrome in case reports?
- Gabapentin
- Carbamazepine
- Lithium
- IV steroids
What medication may reduce the frequency of episodes in Klein-Levin Syndrome?
Lithium
What medication may reduce the duration of episodes in Klein-Levin Syndrome?
IV steroids
What will high leptin levels result in?
Suppress appetite and stimulate energy production
Modafinil to treat residual sleepiness with OSA has what change on the MSLT?
Increase in sleep latency on the MSLT by 1 to 2 minutes compared to baseline
Which is more potent, modafinil or armodafinil?
Armodafinil is 2 times more potent when a steady state is reached
What changes can be seen in REM sleep in a patient with MDD?
- Shortened REM latency
- Increased REM duration
- Increased REM density (increase frequency of rapid eye movements per REM period)
Medication used for cataplexy that is also a metabolite of GABA and is approved for use in children
Sodium oxybate (Xyrem)
A MSLT with a mean sleep latency of < 8 minutes can be found in what % of the normal population?
Up to 30%
Why does narcolepsy result in a rapid transition to REM sleep
- Orexin projects to the REM off neurons in the ventrolateral periaqueductal grey and lateral pontine tegmentum
- Low orexin leads to decreased excitation of REM off neurons
Describe how a MSLT works. How long is each nap? How long will the nap continue once the patient falls asleep?
- Each potential nap runs for 20 minutes and if the patient doesn’t fall asleep the nap is terminated and the latency is 20 minutes
- If the patient falls asleep then the nap will continue for another 15 minutes to see if he will enter REM sleep
- If REM is obtained then the nap is stopped
What 2 actions/treatments can trigger status cataplecticus
- Abrupt withdrawl of antidepressants
- Prazosin
What percent of the time with MSLT be falsely negative in a patient with narcolepsy?
Up to 30%