Trastornos del Sueño Flashcards
15.1.
A 30-year-old woman presents to the outpatient clinic with a
chief complaint of, “I’m always so tired.” She states that she
has always needed more sleep than everyone else “for as long
as I can remember,” and that she would sleep for 12 hours a
day if she could. During the week, she gets in bed around 8
PM
, falls asleep in 10 to 15 minutes, and wakes at 6
AM
to get
ready for work at a city government office. She manages to
stay awake at work and complete her tasks, though she is
drowsy and has some difficulty sustaining attention. On the
weekends she goes to bed at the same time but does not wake
until 10
AM
or later the next day. She states that she has tried
caffeinated drinks, vitamins, and light therapy, and admits to
taking some of a friend’s methylphenidate to see if it would
help, but she remains drowsy. She laments that she is not able
to spend much time with friends because she has to be in bed
so early “or I can’t function the next day.” She denies snoring.
Body mass index (BMI) is 18.5. Vital signs are within normal
limits. Mental status examination reveals a well-nourished,
though slender female in no acute distress. Mood is “tired,”
with congruent affect. She denies auditory or visual
hallucinations. What is the most likely diagnosis?
A. Insomnia disorder
B. Hypersomnolence disorder
C. Narcolepsy
D. Sleep apnea
E. Circadian rhythm sleep disorder
15.1. B. Hypersomnolence disorder
The patient in this case easily falls asleep and reports no difficulty
staying asleep or having early morning awakening, thus ruling out
insomnia disorder. She does not report sudden periods of sleep
during the day or drop attacks of cataplexy. Though her BMI and
lack of snoring do not eliminate sleep apnea as a possibility, they
make the diagnosis less likely. She is sleeping at night as she desires,
and though the lack of improvement with light therapy does not
preclude a diagnosis of circadian rhythm sleep disorder, it makes it
much less likely. Her symptoms fit best with hypersomnolence
disorder, as she reports reduced attention and excessive daytime
sleepiness and time spent asleep
15.2.
What brain structure is responsible for maintaining circadian
rhythm and a regular sleep–wake cycle?
A. Arcuate nucleus
B. Nucleus accumbens
C. Caudate nucleus
D. Suprachiasmatic nucleus
E. Nucleus basalis
15.2. D. Suprachiasmatic nucleus
The nucleus accumbens mediates motivational and emotional
processes and is considered the neural interface between motivation
and action. The caudate nucleus is a part of the basal ganglia that is
involved in working memory and executive functioning. The nucleus
basalis is involved in cortical activation and memory function. The
arcuate and suprachiasmatic nuclei are both located in the
hypothalamus. The function of the arcuate nucleus is control of the
anterior pituitary and feeding, while the function of the
suprachiasmatic nucleus is regulation of biologic rhythms, such as
the circadian rhythm.
15.3.
A 20-year-old male college student reports a 6-month history
of excessive daytime sleepiness to his primary care physician.
He states that he can fall asleep “instantly” at any time, and
that he has nodded off for a few seconds to a few minutes
while driving, while at work, and in class on many occasions.
Despite those brief periods of sleep, he can sometimes recall
“full-on dreams.” He notes that when he first gets up in the
morning, he is sometimes unable to move for about minute,
during which he will “see things from my dreams, but I’m fully
awake.” He states that he gets about 7 to 8 hours of sleep a
night, “but even when I sleep for 12 hours on the weekend, I
still just suddenly fall asleep during the day.” He reports that
he has three to four beers on weekend nights with his friends
and denies drug use. He is on no medications and has no
medical illnesses. He states that he does not snore. BMI is 20.
What hormone is most likely to be deficient in this patient?
A. Leptin
B. Orexin
C. Ghrelin
D. Growth hormone
E. Thyroid-stimulating hormone
15.3. B. Orexin
Orexin is a hypocretin that was discovered in 1998 and is associated
with narcolepsy to the extent that the disorder is now considered to
be caused by hypocretin/orexin deficiency. Ghrelin and leptin are
hormones that help mediate energy balance and satiety. Though
growth hormone surges during sleep, it is not associated with
narcolepsy. A low amount of thyroid-stimulating hormone can lead
to fatigue, but not narcolepsy.
15.4.
A 5-year-old child is brought to the pediatrician by his parents
who report three instances over the past month of the child
getting up during the night and wandering around in the
house. He does not respond when they call his name and does
not appear to do anything purposeful as he walks around. He
is easily redirected to his bed and sleeps without incident for
the rest of the night. He has no memory of the episode the next
day. What is the most likely course of these episodes?
A. They will spontaneously remit after adolescence
B. They will sharply decrease in frequency prior to puberty
C. They will slowly decrease in frequency during young
adulthood
D. They will persist throughout his life
E. They will increase until puberty, then sharply drop off
15.4. A. They will spontaneously remit after adolescence
Sleepwalking most commonly affects children ages 4 to 8 years.
Episodes do not usually require treatment, aside from making sure
the environment is safe (locking doors and windows, keeping
dangerous objects out of reach, not letting the child sleep in a bunk
bed, etc.). For most children, sleepwalking spontaneously remits
after puberty.
15.5.
Chronic alcohol use can lead to insomnia through what
mechanism?
A. Decreased proportion of time in non-rapid eye movement
(NREM) sleep
B. Central nervous system suppression of breathing
C. Arousal-induced sleep cycle fragmentation
D. Increased anxiety prior to sleep
E. Increased sleep latency
15.5. C. Arousal-induced sleep cycle fragmentation
Alcohol is believed to lead to insomnia due to arousals during the
sleep cycle, which lead to a decreased proportion of time spent in
REM sleep. Alcohol can exacerbate obstructive sleep apnea, but a
strong correlation between alcohol and central sleep apnea has not
been shown. Alcohol usually decreases sleep latency and anxiety in
the short term, which can fool people into thinking that it is helpful
for insomnia.
15.6.
The multiple sleep latency test (MSLT) is essential in the
diagnosis of what sleep–wake disorder?
A. Obstructive sleep apnea
B. Central sleep apnea
C. Narcolepsy
D. Circadian rhythm sleep disorder
E. Rapid eye movement (REM) sleep behavior disorder
15.6. C. Narcolepsy
A polysomnogram can be used in the evaluation of sleep apnea, REM
sleep behavior disorder, narcolepsy, and other causes of daytime
sleepiness. If after assessing sleep quality and quantity during the
polysomnogram narcolepsy is still suspected, an MSLT will be
performed. The MSLT involves five, 20-minute opportunities for a
patient to nap. If the patient falls asleep and REM sleep waves are
detected on two occasions (or one occasion if the previous
polysomnogram revealed REM sleep within 15 minutes of sleep
onset), the diagnosis of narcolepsy is made.
15.7.
A 40-year-old woman reports a 10-year history of difficulty
falling asleep. She believes that the problem began when she
worked a highly stressful job during which she “went to sleep
worried about getting yelled at by my boss the next day.” Even
after she changed jobs, the anxiety about not being able to
sleep remained. She states that she is now at the point where
she gets in bed frustrated because she knows she will be awake
for hours. She used to watch the clock, but stopped doing that
a month ago, as it was making her more upset at night.
However, it has not improved the insomnia. She tried
melatonin, which she felt was initially helpful, but she no
longer derives benefit even after increasing the dose. She has
also tried over-the-counter diphenhydramine, but felt that she
was getting addicted to it. She denies symptoms of depression.
What should be the next step in her treatment?
A. Eszopiclone therapy
B. Sleep hygiene
C. Relaxation therapy
D. Suvorexant therapy
E. Cognitive behavioral therapy for insomnia (CBTi)
15.7. E. Cognitive behavioral therapy for insomnia (CBTi)
CBTi has repeatedly shown sustained improvement, up to at least 36
months in some studies, in insomnia. While it does not work as
quickly as pharmacologic means, there is no apparent rebound effect
from discontinuation, thus making pharmacologic treatments less
effective long term, even those approved for long-term use such as
eszopiclone. Sleep hygiene is a component of CBTi, and by itself is
not as effective. Relaxation therapy can be helpful for those who
experience tension prior to bedtime, and is often paired with other
insomnia treatments such as sleep hygiene.
15.8.
Treatment of cataplexy involves medications with what
physiologic effect as the mechanism of action?
A. Inhibition of muscle atony
B. Suppression of REM sleep
C. Central nervous system (CNS) stimulation
D. Suppression of sleep-related hormones
E. Muscle relaxation
15.8. B. Suppression of REM sleep
Medications such as tricyclic antidepressants and selective serotonin
reuptake inhibitors (SSRIs) are used in the treatment of cataplexy for
their ability to suppress REM sleep, not sleep hormones. Inhibition
of muscle atony occurs in REM sleep behavior disorder. CNS
stimulation, which occurs with psychostimulants, can be helpful for
narcolepsy, though not cataplexy. CNS depressants such as sodium
oxybate can be helpful for cataplexy. There have been case reports of
muscle relaxants used for cataplexy, but this is not first line and
should be avoided when sodium oxybate is used
15.9.
A 50-year-old woman complains of difficulty sleeping for the
last 6 months. She states that when she gets in bed, she tosses
and turns because she feels that “I just need to move.” She also
reports that she sometimes feels like bugs are crawling on her
skin, particularly her legs, which is alleviated by getting out of
bed and walking around. She then gets back in bed, but the
sensations return in about 30 minutes. She ends up staying
awake almost all night two to three times a week. She notes
that she is falling asleep at work because she is so tired. After
further history and a physical examination, what lab test
should be ordered?
A. Complete blood count with differential
B. Liver function tests
C. Urine drug screen
D. Ferritin level
E. Triglyceride level
15.9. D. Ferritin level
About 15% of patients with restless leg syndrome have an iron
deficiency, with a serum ferritin level of <50 mcg/L. In these
patients, in addition to first-line, dopaminergic agonists such as
pramipexole, rotigotine, and ropinirole, iron supplementation can be
helpful
15.10.
The narcolepsy medication pitolisant works through what
pharmacologic mechanism?
A. Norepinephrine–dopamine reuptake inhibition
B. Dopamine reuptake inhibition
C. H3 receptor antagonism/inverse agonism
D. D2 receptor partial agonism
E. 5HT3 antagonism
15.10. C. H3 receptor antagonism/inverse agonism
Pitolisant, an U.S. Food and Drug Administration (FDA)-approved
treatment for narcolepsy, is a selective H3 receptor agonist/inverse
agonist. Another FDA-approved medication for narcolepsy,
solriamfetol, acts through norepinephrine–dopamine reuptake
inhibition, as do stimulants, which are often used. Modafinil and
armodafinil block dopamine reuptake.
