Get ahead with a $300 test prep scholarship
| Enter to win by Tuesday 9/24
AASM Board Review - Lecture 5 Circadian Rhythm
Terms in this set (64)
Effects of circadian rhythms on growth hormone?
growth hormone doesn't peak unless sleep occurs
when does performance (alertness, cognitive performance, short term memory) hits nadir?
at CT min
what tests are helpful in determining circadian rhythm characteristics?
munich chronotype questionnaire
ICSD-3 definition of advanced sleep wake phase disorder?
A - symptoms: all of the following
- advance in major sleep episode relative to desired / required sleep wake times leads to early evening sleepiness and waking earlier than desired
- symptoms present for 3 or more months
- improved sleep quality and longer sleep duration when patients sleep ad libitum at their naturally advanced sleep wake schedule
B - assessment:
- sleep log and actigraphy for 7 or more days shows stable advanced habitual sleep period
ICSD 3 definition of circadian rhythm sleep-wake disorder
ICSD 3 - A + B + C
A. Symptoms: insomnia or EDS or both
B. Disruption of sleep-wake rhythm
- recurrent or persistent misalignment between the desired or imposed sleep schedule and the circadian sleep-wake rhythm or by a disorder of the endogenous circadian system
C. Associated features
- distress or impaired functioning
associated conditions with advanced sleep wake phase
- smith magenis
what's the mutation associated with familial advanced phase sleep disorder?
missense mutation in a casein kinase (CK1 epsilon) binding region of a period gene (HPer2) --> hypophosphorylation by CK1 epsilon in vitro --> hypophosphorylation on the Period protein causes promotion of its transcription --> decrease in period length clock --> shortened endogenous circadian period
onset of advanced sleep phase issues?
middle or old age
diagnosis of advanced sleep wake phase disorder
sleep logs or actigraphy
rule out depresion
therapy for ASWPD
- which modalities are not recommended
early evening bright light therapy (before CT min)
avoid light in early AM
- occasionally early AM melatonin could be helpful (not recommended since it can cause daytime sleepiness)
- chronotherapy not recommended as sole therapy
what other tests are helpful in providing information about ASWPD?
advance of > 2 hours in timing of other circadian rhythms such as DLMO or urinary 6 sulfatoxymelatonin (helpful but not required)
side effects of light therapy
can cause mania
what conditions are contraindications for light therapy
underlying eye disease or photosensitive disorders
Review human phase response curve to bright light and melatonin
- DLMO is the up airway
- rectangle typical sleep period
- down arrow in box is CT min
- before DLMO --> advances bedtime
- after DLMO --> causes delay
Of note, with higher doses of melatonin, maximal effect occurs at an earlier time compared to lower dose of melatonin.
Which proposed treatment of ASWPD is the only one with evidence for in the AASM guidelines?
Everything else has no recommendation:
- avoidance of light
- sleep promoting medications
- timer oral melatonin
ICSD-3 Definition of delayed sleep-wake phase disorder
A. Symptoms - all of the following
- delay in major sleep episode relative to desired / required sleep wake times leading to sleep-onset insomnia and sleep-offset sleepiness
- symptoms are present for 3 or more months
- improved sleep quality and longer sleep duration when pts sleep ad libitum at their naturally delayted sleep wake schedule
B. Assessment -
sleep log and actigraphy for 7 or more days shows stable delayed habitual sleep period
onset of DSWPD?
when does severity diminish in DSWPD?
consequences of DSWPD?
habitual absence or tardiness
Treatment of DSWPD
- light upon awakening --> do not give before CTmin since that could delay things further
- avoid evening light
- low dose melatonin in early evening (0.5 mg 4-6 hours before DLMO or 13-14 hours after wake time)
- chronotherapy as adjunct
Describe progressive phase delay chronotherapy
bedtime and wake times delayed by about 2-3 hours a day until desired bedtime reached
Describe progressive phase advance chronotherapy
gradually advancing bedtimes and wake times by 30-60 min until desired schedule attaioned
Describe scheduled shift techniques
6 consecutive nights on usual sleep schedule followed by one night of sleep deprivation and 6 subsequent days with a 90 minute advance
AASM guidelines - what's the only treatment with evidence for DSWPD?
- what about with depression, psych issues
timed oral administration of melatonin
- for adults with/without depression
- child / adolescents without comorbidities
- children / adolescents with psych issues
- light therapy + behavioral interventions for children/adolescents
- light therapy, avoidance, wakefulness promoting medications, etc.
*** which patients more likely to have irregular sleep-wake rhythm d/o
highest risk: dementia
neurodegenerative disorders (sundowning) and developmental disorders (autism, behavioral issues, hungtington, TBI, MR)
ICSD-3 definition of irregular sleep wake rhythm disorder
A. Symptoms - all of the following
- chronic pattern of irregular sleep-wake episodes in a 24 hour period leading to nighttime insomnia and dayttime sleepiness
- symptoms present for >= 3 months
B. Assessment -
sleep log and actigraphy for 7 or more days shows multiple (3 or more) irregular sleep bouts rather than single major episode during 24 hour period
treatment of ISWRD - AASM guidelines for dementia, neurologic disorders. which are contraindicated?
- light therapy in elderly with dementia
- timed oral melatnonin in children/adolescents with neurologic disorders
- oral melatonin in elderly with dementia
- combination treatment of light and melatonin in elderly, demented patients
- sleep promoting medications in elderly with dementia
when is sleep wake variability pathologyic in children?
common among newborn infants
- not considered pathologic until after 6-9 months of age when consolidation of nighttime sleep occurs
ICSD3 definition of non 24 hour? how is assessment different from advanced and delayed phase sleep disorders?
A + B
A. Symptoms - all of the following
- misalignment between non entrained endogenous circadian sleep wake rhythm and the external 24 hour light dark cycle leads to periods of insomnia or daytime sleepiness alternating with asymptomatic periods
- symptoms of 3 or more month s
- sleep log and actigraphy for 14 or more days show progressive daily delay in sleep wake schedule and circadian period longer than 24 hours
symptoms of non 24
periodically recurring problems of insomnia or EDS alternating with complete, but brief, disappearance of symptoms
time of onset of non 24
at any age
what are the causes of non 24 hour in sighted individuals?
decreased social cues
mutation in CK1 gene
*** AASM treatment guideline evidence for therapies? who is treated with oral melatonin?
Weak for: blind adults for oral melatonin or agonists
Timing of jet lag and onset of symptoms?
insomnia or EDS within 1-2 days after travelling across 2 or more time zones
effects of travelling west or east?
westward --> phase advanced relative to new clock time
westward effects: early evening sleepiness and early morning awakening
eastward --> phase delayed in relation to new clock time
eastward effects: sleep onset insomnia and difficulty awakening next day
other non sleep disturbances with jet lag?
when are symptoms worse in jet lag?
- eastward travel
- greater amounts and rates of time zone -
- Older adults
*** summary for phototherapy in jet lag
in travel within USA: get what you do not have
Eastward: do not need evening city lights of NY, get morning light (obtain bright light after CT min, avoid bright light before)
Westward: do not need sunny days of california; get afternoon light (obtain bright light before and avoid bright light after CTmin)
how do recs change for more travel?
if more than 7-8 time zone changes (each time zone is 1 hour) --> recommendations change
NY to asia --> morning light phototherapy
California to europe - afternoon light
when to consider another diagnosis if jet lag persists?
if > 2 weeks after travel --> consider another diagnosis
in a pt with normal circadian sleep wake cycle (11p to 7 am) --> when is the best impact for phototherapy
largest phase advances or delays occur when light treatment is initiated between 6-8 am or 2-3 am respectively (basically 3 hours before or after CT min)
Bed times and wake times for ASWPD and DSWPD
bedtime 6-9 pm
wake 2-5 am
bedtime 1-6 am
when does alertness peak?
early evening hours
when does alertness decreased during the day? when is it lowest?
- midday decrease in alertness at 2-4pm
- lowest alertness at 4-6 am
what are the major circadian photoreceptors?
melanopsin-containing retinal ganglion cells --> take the light and commmunicate to SCN via retinohypothalamic tract
when is CBT min?
2-3 hours before awakening from unconstrained sleep (usually 4-5 am)
easy formula: DLMO + 7 (CT min usually occurs about 7 hours later than DLMO)
when does DLMO occur?
approximately 2 hours before habitual sleep onset
- usually can be measured by checking slaivary or plasma melatonin preformed in dim light (5 lux)--> DLMO occurs when starts increasing (3 picograms)
what's the pathway for melatonin secretion after the SCN?
SCN --> paraventricular nucleus --> intermediolateral cell column --> superior cervical ganglion --> pineal gland
when is the greatest effect of light therapy on phase advance and delay?
3 hours before or after CT min has greatest effect according to light phase response curve
*** TEST QUESTION what treatment therapies would be useful in optimizing sleep for night shift?
- bright light - when?
- avoidance of bright light?
- melatonin - when
- time to go to bed at end of shift?
- when to use stimulants and caffeine?
- bright light 3 to 6 hours during start of shift (to phase delay)
- short scheduled naps before or during shift
- avoidance of bright light on the way home in the morning (to help prevent phase advances)
- melatonin in am (to help with sleep as a hypnotic and phase delay events)
- going top bed as soon as possible after arriving at home
- stimulants (30-60 minutes before night shift)
- caffeine first 2 hours of night shift
Role of hypnotics and night shift?
- helpful with TST
- however, doesn't help with night alertness
how soon does jet lag symptoms occur?
within 1-2 days of flight
*** TEST question:
how would you get prevent jet lag before the trip
Before travel, restting body clock to minimize necessary change.
- shift sleep 1-2 hours earlier before trip
- bright light in am
- shift sleep 1-2 hours later before trip
- evening light
*** TEST question:
how would you get prevent jet lag during flight
- applies to both directions of travel:
1) sleep if possible
2) sleep during time corresponding to night in the destination
3) drink water, avoid alcohol
*** TEST question:
how would you prevent jet leg on arrival:
- light exposure?
Eastward travel: seek morning light (to phase advance)
Westward tavel: seek evening light (to phase delay)
*** Test Question
- if crossing more than 8 time zones, what's the approach to jet lag?
Avoid light when it may inhibit adaptation.
- for first 2 days after arrival, avoid bright light for the first 2-3 hours after dawn (to prevent inappropriate phase delay)
- on third day, seek exposure to bright light in the AM
- for 2-3 days, avoid bright light in late evenings )to prevent inappropriate phase advance)
- on third day, seek exposure to bright light in evening
*** TEST when to take melatonin to help with jet lag?
Eastward: 0.5 - 3mg at local bedtime nightly until phase advanced is achieved
- take 0.5 milligrams during second half of night (after CBT min to phase delay)
*** TEST when to use caffeine for jet lag?
drink judiciously and avoid after midday
*** TEST w when to consider hypnotics to help with jet lag?
consider taking at bedtime for a few days
when is the melatonin not useful since endogenous melatonin already high?
between DLMO and CBT
when is phase delay with melatonin best? why isn't it used?
1-2 hours after spontaneous awakening. however, hypnotic effects may be an issuesfor both:
what's the maximal phase delay you can have with melatonin?
10 hours after DLMO
why are larger melatonin doses (3-5mg) given at a different time?
- higher doses have hypnotic effects.
- if given closer to bedtime, may reduce SCN alerting signal and dampen wake maintenance zone
*** When is optimal timing of melatonin dose for achieving maximal phase advance?
@ 0.3-0.5 mg
- before DLMO: 2-3 hours
- before habitual sleep onset: 4.5-5 hours
- before CT min 9 hours
@ 3 mg
- before DLMO: 5 hours
- before habitual sleep onset: 7.5 hours
- before CBT min 12 hours