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Flashcards in Sleep Deck (58):
1

Polysomnography

full/level1 sleep study
Provides information on sleep architecture

2

components of polysomnogram

EEG
EMG (submentalis, ant. tibilalis)
EOG (electro-occulogram)
ECG
Airflow (nasal pressure, thermistor)
Respiratory effort
digital oximetry

3

Ambulatory sleep studies

DIgital/level 3
useful only for sleep apnea
no information on sleep stages, sleep/wake cycle
measures:
- airflow
- respiratory effort
- digital oximetry
- +/- body position

4

Sleep staging

amplitudes and waveforms scored in 30 second epochs
EEG
Eye movements (rolling at sleep onset, rapid in REM sleep)
Muscle tone (EMG) - lessens with drowsiness and sleep depth, absent in REM

5

Normal sleep

Sleep latency

6

Non-REM sleep

Stages I, II, III
I: still input from environment
II: medium sleep
III: deep sleep

7

REM sleep

phasic: eye movements, twitches, variable autonomic activity
Tonic: EMG suppression, high arousal threshold, elevated brain temperature, poikilothermia, penile tumescence
Sleep apnea often worst during REM since muscles are relaxed

8

EEG patterns

Stage 1: theta
2: sleep spindles and mixed EEG
Stage 3: more delta waves
REM: low-voltage, high-frequency waves

9

Hypnogram

~ 90 min cycles between REM and non-REM
Elderly: shorter cycles, shallow sleep

10

Stage I of sleep

light sleep
transitional stage passed through from wake to sleep and sleep to wake
usually ~5% of TST
when increased --> indicates sleep disruption

11

Stage II of sleep

most of the night spent in this stage

12

Stage III of sleep

deepest - hard to awaken
Sleep drunkenness: sleep inertia when awakened; parasomnias occur from this stage
Most restorative
often reduced by benzodiazepines
maintained by zopiclone, zaleplon, zolpidem

13

Stage REM

dream sleep; ver narrative
tonic/phasic stages
tonic: voluntary muscle atonia
phasic: movements

14

Latency to stage REM shortened causes

REM rebound: first night of CPAP, drug/medication withdrawal
Depression (psychotic > milder forms)
Narcolepsy

15

Sleep and aging

more stage I, less stage III
more awakening
brain shrinks a bit - less deep sleep??

16

Complaints of normal elderly about sleep

insomnia
relative advance of sleep phase
shallow sleep
less restorative
dream content often unpleasant
daytime sleepiness

17

Melatonin pathway

Inhibited by light
stimulated by darkness
Retinohypothalamic tract --> SCN --> made in pineal gland to go to superior cervical ganglion

18

Sleep disturbances commonly seen in the elderly

Respiratory sleep disorders
Restless legs/periodic limb movements
REM sleep behaviour disorder

19

Respiratory sleep disorders

Primary snoring
upper airway resistance syndrome
OSA - hypopnea syndrome
--> apnea: cessation of airflow >=10 seconds
--> hypopnea: decrease in airflow >=10 seconds
- respiratory effort persists
Central sleep apnea - no respiratory effort
Mixed sleep apnea

20

OSA night time symptoms

snoring
witnessed apneas
choking
dyspnea
restlessnes
snocturia
diaphoresis
reflux
drooling

21

OSA daytime symptoms

sleepiness, fatigue
morning headaches
poor concentration
decreased libido/impotence
decreased attention
depression
decreased dexterity
personality changes

22

OSA risk factors

Obesity
neck circumference over 40 cm
macroglossia
dental overjet and retrognathia
high/narrow hard palate
elongated/low lying uvula
enlarged tonsils, adenoids
crossbite/dental malocclusion
prominent tonsillar pillars
enlarged nasal turbinates
deviated nasal septum
narrow mandible
narrow maxilla

23

Central sleep apnea

similar daytime symptoms to OSA
typically have history of:
- cardiac disease
- stroke
- opioid use

24

Restless legs syndrome features

urge to move limbs often associated with paresthesias/dysesthesias
symptoms worse of present only during rest
partially/temporarily relieved by activity
nocturnal worsening of symptoms
Diagnosis usually made clincially, but may be confirmed through the Standarized Immobilization Test

25

Associated features of restless legs syndrome

response to dopaminergic therapy in almost all cases
periodic limb movements occur during sleep/wakefulness in 80-90% of patients
usually progressive with age
no clear medical/physical pathology (primary form)

26

Demographics of restless legs syndrome

5-10% of adults of Northern European studies
lower in Indian/Asian studies
treatment typically sought after age 40
1.5-2x more common in women

27

Predisposing factors of restless legs syndrome

Fe deficiency
peripheral neuropathy
sedating antihistamines, dopamine antagonists, and most antidepressants (not buproprion)
family affected in >50%
increased risk (3-6x) in 1st degree relatives

28

Causes of secondary RLS

pregnancy --> dilutional anemia
end-stage renal disease
Fe deficiency (involved in dopamine synthesis?0
)

29

Treatment of RLS

underlying factors (anemia, renal disease, neuropathy)
Medication options:
- gabapentin, pregabalin
- dopamine agonists
- clonazepam
- opioids in very severe cases

30

Periodic limb movement disorder essential features

EMG from the polysomnogram demonstrates repetitive, highly stereotyped limb movements that meet recording criteria = inter-movement interval of 5-90 seconds
PLM index exceeds 5/hour (children) and 15 (adults)
clinical sleep disturbance or a complaint of daytime fatigue

31

Periodic limb movement disorder treatment

only if clinically indicated (clear sleep disruption)
same option as RLS

32

REM sleep behaviour disorder essential features

presence of REM sleep without atonia
at least one of the folllowing:
- sleep related injurious, potentially hazardous, or disruptive behaviours by history
- abnormal REM sleep behaviours documented during PSG

Absence of EEG epleptiform activity during EEG

33

Associated features of RSBD

dream enactment typically occurs >90 min after sleep initaition
episode ends when individual awakens quickly, becomes alert, and reports dream
injury common secondary to violent dream enactment
sleepwalking uncommon
may have prodrome of sleep talking, yelling, twitching
patients often present after injury to self or bed partner

34

RSBD onset/course

gradual/rapid onset, progressive
delayed emergence of neurodegenerative disorder is very common (2/3 later develop Parkinson's)
can be simply a symptom of narcolepsy

35

RSBD pathology

alpha-synucleinopathy
protein aggregates in vulnerable populations of neurons and glial cells

36

Predisposing/precipitating factors of RSBD

underlying neurological disorder, especialyl alpha-synucleinopathies (Parkinson's LBD, multiple system atrophy)
narcolepsy
stroke
medications/withdrawal

37

Management of RSBD

safety first - remove obstacles, etc
Medication - best evidence clonazepam, effective in preventing violent dream enactment in most cases

38

Sleep and AD

disruption common in AD (19-44%)
Related to patient institutionalization
Negative impact on patient and caregivers' QOL

39

Better management of sleep in AD

priority for improving comprehensive management of patients with AD
No long-term data
no data on behavioural interventions

40

Features of sleep in AD

similar to but worse than disturbances seen in non-dementing elderly
increased freq/duration of awakenings
increased stage I
decreased stage III, REM sleep
increased daytime napping
sleep disturbances associated with:
- increased memory/functional impairment
- more rapid cognitive decline
More severe in more demented patients

41

Mechanism of sleep disturbance in AD

Loss/damage to neuronal pathways that initiate and maintain sleep
Degenerative changes in brainstem regions/pathways that regulate sleep-wake cycles
Changes in cortical tissue that generate EEG low-wave activity during sleep
Changes in hypothalamic-suprachiasmatic nucleus and other parts of the circadian timing system
severe: day-night reversal occurs

42

Sleep apnea and AD

significant correlation between dementia and sleep apnea severity

apnea associated with increased nocturia
worsens with sedative medications

43

Sleep disturbance in AD treatments

Buspirone: anxiety/depressive
SSRI: depressed/non-specific mood
Agitation: benzo, anti-psychotic
Insomnia:trazodone, zopiclone, benzodiazepines,
use safest, most effective drug at lowest dose, short duration
Watch out for side effects: falls, fractures, confusion, etc

44

Behavioural interventions in sleep disturbance in AD

no empirical studies in this population
Physical environment/institutional routines
reduce daytime napping
address care-giver concerns about "upsetting routine"

45

Ideal hypnotic

rapid absorption
short half-life
no drug-drug interactions
no tolerance to effect
free from side effects (memory, psychomotor)
no rebound
cheap

46

Rebound insomnia

Transient exacerbation of insomnia commonly occurs when sedative/hypnotic medications are withdrawn

47

Sleep hygiene basic rules

sleep only as much as needed to feel rested, get out of bed
keep regular sleep schedule
avoid forcing sleep
Exercise regularly >=20 min, preferably 4-5 hours befor bedtime
avoid caffeinated beverages after lunch
avoid alcohol near bedtime
avoid smoking
don't go to bed hungry
adjust bedroom environment
avoid prolonged use of light-emitting screens befoe bedtime
stimulus control!!

48

Rx sleep onset insomnia

Short-acting
Zaleplon, zolpidem, triazolam, lorazepam
Ramelteon: melatonin agonist - more effective in sleep onset rather than sleep maintenance insomnia
Adverse effects milder in melatonin agonists than benzodiazepines

49

Rx sleep maintenance insomnia

Longer-acting preferable
Zolpidem extended release, eszopiclone, temazepam, estazolam, low dose doxepin
- may increase risk for hangover sedation

50

Benzodiazepine MOA in insomnia

binds several subtypes of GABAa receptors
reduce time to onset of sleep
prolonged stage II
prolong total sleep time
may slightly reduce amount of REM
decrease anxiety, impair memory, have anticonvulsive properties

51

Short acting genzo

triazolam

52

Intermediate acting benzo

estazolam
lorazepam
temazepam

53

Long acting benzo

flurazepam
quazepam

54

Nonbenzodiazepine receptor agonists

more targeted action at one GABA type A receptor
greater specificity - less anxiolytic and anticonvulsant
improve subject/veobjective sleep outcomes
decrease sleep latency & number of awakenings, while improving sleep duration and sleep

55

Zaleplon

very short halflife
effective for sleep-onset insomnia
not indicated for long-term use

56

Zolpidem

1.5-2.4 half life
for sleep onset insomnia
not indicated for long-term use

57

Eszopiclone

longest half life of approved nonbenzos
effective for both sleep onset/maintenance insomnia
not limited to short-term use, little evidence for abuse/dependance

58

Zolpidem extended release

1.5-2.4 half life
improve both sleep onset/maintenance insomnia without hangover effects
not limited to short-term use, little evidence for abuse/dependence in most patients