Sleep Disorders Flashcards
(92 cards)
1
Q
List 4 broad causes of daytime sleepiness, from most common to least common
A
Lifestyle (not getting enough sleep!) Drugs/alcohol (e.g. benzodiazepenes, anti-depressants) Sleep breathing disorders RLS/periodic limb movement disorder Neurological disease Insomnia Narcolepsy Idiopathic hypersomnia Circadian disorders Psychiatric disorders Post-viral
Lifestyle (not getting enough sleep)
Conditions disrupting sleep:
Drugs/alcohol
Sleep-related conditions
2
Q
Distinguishing between sleepiness vs tiredness/lethargy
A
Sleepiness: narrower differential diagnosis
Tiredness/lethargy: broader differential diagnosis (chronic disease)
3
Q
How can sleepiness be distinguished from tiredness/lethargy?
A
Epworth sleepiness scale: patient is asked what their chance of dozing would be in a number of contexts (normal 15 confers 2x risk of MVA; use in fitness to drive assessments)
4
Q
Summarise the respiratory control changes at sleep onset
A
Loss of wakefulness drive to breathe and behavioural influences
Down-regulation of respiratory reflexes, chemosensitivity, and upper airway and respiratory pump muscle tone (thereby increasing upper airway resistance)
5
Q
What is the major regulator of breathing during sleep?
A
Chemical control
6
Q
What are the cardinal symptoms of OSA?
A
Heavy snoring
Excessive daytime somnolence
Witnessed apnoeas
7
Q
List some other nocturnal symptoms of OSA
A
Disrupted/restless/unrefreshed sleep
Nocturnal choking and gasping
Nocturia
8
Q
Mechanism of OSA
A
pO2 starts to fall, pCO2 starts to rise
Individual tries to breathe harder but this increases the negative pressure, causes closing of upper airway
Central drive reaches threshold for waking
9
Q
List some other daytime symptoms of OSA
A
Headaches (nocturnal/morning) Memory/cognitive/concentration deficit Mood change (depression/irritability) Sexual dysfunction (decreased libido or impotence) Uncontrolled HTN
10
Q
List 5 cardio-respiratory effects of OSA
A
HTN Cor pulmonale MI Arrhythmias/sudden death Polycythaemia
11
Q
List 5 risk factors for OSA
A
Age Male gender Obesity Alcohol/sedatives Upper airway morphology including nasal obstruction
12
Q
What are the criteria for diagnosis of OSA?
A
Apnoea hypopnoea index (AHI) >5 events/hr
5-15 mild, 15-30 moderate, >30 severe (ranges not really useful; better to assess symptoms)
13
Q
How can OSA be diagnosed?
A
In laboratory OR at home full polysomnography
14
Q
Define apnoea
A
Complete cessation of airflow for ≥10 secs, regardless of O2 desaturation
15
Q
Define hypopnoea
A
≥30% reduction in airflow associated ≥3% O2 desaturation or an alpha wave arousal from sleep
16
Q
What are the 4 options for OSA management?
A
Conservative treatments
CPAP
Oral appliances
Surgery
17
Q
List 5 options for conservative treatment of OSA
A
Weight loss Avoid alcohol, tobacco and sedatives Body position Treat nasal congestion Treat medical disorders
18
Q
Where might the use of oral appliances be advised?
A
Snoring
Mild to moderate OSA
Failed CPAP treatment
19
Q
List some contraindications to oral apliances for management of OSA
A
Dentures or lack of teeth Periodontal problems TMJ disorder Severe nasal obstruction Severe hypoxia
20
Q
List some SEs of oral appliances for management of OSA
A
Excessive salivation
Discomfort in the teeth and jaw
Movement of teeth
TMJ dysfunction
21
Q
List 3 types of sleep disordered breathing
A
OSA
Central sleep apnoea
Sleep hypoventilation
22
Q
Define central sleep apnoea
A
Apnoeas or hypopnoeas caused by reduction in central respiratory drive
23
Q
What are the 4 main causes of central sleep apnoea?
A
Cardiac failure (Cheyne-Stokes respiration; main cause)
High altitude
CNS disorders (e.g. CVA)
Idiopathic
24
Q
How is central sleep apnoea managed?
A
Depends on underlying causes (e.g. for Cheynes-Stokes, manage heart failure)
25
List some causes of hypoventilation
```
Reduced respiratory centre activity
Neuromuscular disease
Chest wall deformity
Obesity
Increased ventilatory requirements
```
26
Victorian requirements for driving
AHI >35
| ESS >15
27
55 year old male, 110 kg, taxi driver
Fell asleep at the wheel and was woken by passenger
Long Hx of snoring, sleeps alone
Driving 15 hours per day; says he sleeps on the rank
6 hours per night in bed
Likely Dx?
OSA
28
Is OSA more common in males or females?
Males
29
List 5 neuropsychological effects of OSA
```
Excessive sleepiness
Psychological problems
Stroke
Dementia
In children: behavioural problems, poor school performance, ADHD
```
30
Describe 4 factors contributing to the pathogenesis of OSA
Anatomically narrow upper airway
Upper airway muscle weakness
Poor respiratory control (with propensity to develop cyclical breathing)
Reduced arousal threshold (leading to cycling)
31
What are the diagnostic criteria for OSA?
AHI >5 events per hour (events/total sleep time)
32
How is the severity of OSA graded?
Mild: 5-15
Moderate: 15-30
Severe: >30
33
How effective is weight loss as a treatment for OSA?
10% weight loss results in a 26% reduction in AHI
34
Adaptive Servo-Ventilation (ASV)
Uses an algorithm which detects significant reductions or pauses in breathing and intervenes with just enough support to maintain the patient's breathing at 90% of what had been normal prior to decreased breathing
Algorithm is based off a set rate of breaths per minute that the patient should be taking; when the patient's breathing dips below these rates, the ASV delivers just enough air pressure to keep the patient breathing regularly
35
How is Cheyne-Stokes breathing managed?
Treat HF
CPAP
?O2
Adaptive Servo-Ventilation (ASV)
36
How is idiopathic CSA treated?
?O2
| ?NIV
37
Describe the "balance of forces" in respiration
Pro-respiratory: respiratory drive, nerve integrity, muscle integrity, "bellows" structure
Anti-respiratory: upper and lower airway resistance, elastance, gas exchange requirements
38
22 year old male, difficulty sleeping since early teens, mainly due to sleep onset insomnia
Once asleep sleeps well, but has to get up for work after 4/24
Describes that he "cannot get comfortable" in bed
Non-snorer, thin
Minimal alcohol, no illicit drugs, 1 coffee daily
What aspects of Hx would be consistent with a diagnosis of chronic insomnia?
Subjective dissatisfaction with sleep quality or duration, difficulty falling asleep at bedtime, waking up in the middle of the night or too early in the morning, or non-restorative or poor quality sleep
Associated daytime symptoms and functional impairments
39
Is chronic insomnia more common in females or males?
Females
40
What is "primary" insomnia?
A disorder of "hyperarousal"
41
List 6 changes seen in primary insomnia which may be associated with its pathophysiology
```
Increased anxiety
Increased HPA axis activity
Increased HTN
Increased ANS activity in sleep
Changes in sleep EEG with more faster frequency waves
Increased brain glucose uptake in sleep
```
42
List 8 disorders which may contribute to the onset of insomnia
```
OSA
Circadian disorders
Restless legs
Psychiatric disorders
Substance abuse
Pain
Urinary problems
Rx
```
43
How can insomnia be assessed/monitored?
Sleep diary
| Actigraphy
44
8 treatment strategies for insomnia
```
Treat comorbid disorders
Stimulus control therapy
Sleep restriction
Relaxation
Biofeedback
Paradoxical intention
Sleep hygiene
Short term hypnotics
```
45
What pharmacological treatments are used for insomnia?
```
Benzodiazepines
Non-benzodiazepines
Antidepressants
Valerian
Antihistamines
```
46
What principles must be considered when deciding whether to manage insomnia pharmacologically?
Hypnotic medications should not be the first choice of treatment
Rx should be used in short term management of idiopathic or psychophysiological insomnia
Rx should be combined with non-pharmacological measures when tapering the dose
47
List 7 circadian disorders
```
Delayed sleep phase syndrome
Advanced sleep phase syndrome
Non-24 hr circadian rhythm
Free-running rhythm
Jet lag
Shift work disorder
Seasonal affective disorder
```
48
In what % of the population does restless legs syndrome occur?
5-15%
| Increases with age
49
List the 4 International Restless Legs Study Group Criteria
Desire to move the extremities often associated with parasthesias or dysaesthesias
Motor restlessness
Worsening of symptoms at rest with at least partial and temporary relief during activity
Worsening of symptoms in the evening or at night
50
List 5 secondary causes of restless legs syndrome
```
Iron deficiency
Renal failure
Peripheral neuropathy
Lumbosacral radiculopathy
Pregnancy
```
51
How is familial restless legs syndrome inherited?
AD
52
List 5 consequences of restless legs syndrome
```
Sleep disturbances
Tiredness or fatigue during daytime
Reduced emotional well-being/QOL
Avoidance of social activities
Possibly higher incidence of CVS risk factors/CVS disease
```
53
What is periodic limb movement disorder?
Repetitive movements of the limbs (usually legs) that occur during sleep and may be associated with arousal
54
How is periodic limb movement disorder diagnosed?
PLM index on polysomnography
55
What is the relationship between RLS and PLM?
80% with RLS have PLM
| >50% PLM have RLS
56
What is narcolepsy?
Disorder of sleep regulation, with an intrusion of some REM sleep into wakefulness and abnormal regulation sleep timing
57
What is the pathophysiology of narcolepsy?
Deficiency in the neurotransmitter orexin
58
When is the typical onset of narcolepsy?
Begins in teens and 20s (but can occur after 40)
59
What is the inheritance pattern of narcolepsy?
AD with incomplete penetrance
| Associated with HLA-DQB1*0602
60
What are the main features of narcolepsy?
Excessive daytime sleepiness
| Manifestations related to REM sleep
61
What are the features of excessive daytime sleepiness seen in narcolepsy?
"Sleep attacks", ESS>15, refreshed following nap
Abnormally timed REM sleep
Abnormal result on a multiple sleep latency test (MSLT)
62
What manifestations related to REM sleep may be seen in narcolepsy?
Hypnagogic/hypnopompic hallucinations
Sleep paralysis (complete inability to move for 1-2 minutes after awakening)
Cataplexy
63
Cataplexy
A medical condition in which strong emotion or laughter causes a person to suffer sudden physical collapse though remaining conscious
64
What are the criteria for a diagnosis of narcolepsy?
Excessive daytime sleepiness
Cataplexy
MSLT (mean sleep latency
65
SOREM
Sleep-onset rapid eye movement
66
How can narcolepsy be treated?
General measures
| Pharmacologically
67
List 5 general measures used to manage narcolepsy
```
Avoid shifts in sleep schedule
Avoid heavy meals and alcohol intake
Regular timing of nocturnal sleep
Strategically timed naps, if possible (e.g. 15 mins at lunchtime, 15 mins at 5.30pm)
Career counselling
```
68
List 2 types of pharmacological treatments used to manage narcolepsy
Stimulants (e.g. modafinil, amphetamines)
| REM-suppressing drugs (e.g. SSRIs, tricyclics)
69
2 examples of amphetamines used in the treatment of narcolepsy
Dexamphetamine
| Methylphenidate
70
2 examples of SSRIs used in the treatment of narcolepsy
Fluoxetine
| Venlafaxine
71
List 5 diagnostic criteria for idiopathic hypersomnia
DIAGNOSIS OF EXCLUSION:
Complaint of EDS and prolonged, often unrefreshing naps
Difficulty waking up in the morning or after a nap (sleep drunkenness)
Insidious onset prior to age 30
Duration of at least 6 months
Exclusion of conditions that may cause the same symptoms on polysomnogram and MSLT (i.e. latencies between 5-10 mins, no SOREMs)
72
Describe the pathogenesis of idiopathic hypersomnia
Unknown
73
How is idiopathic hypersomnia treated?
Stimulants
| 1/4 spontaneously improve
74
What is a parasomnia?
Undesirable behaviour or experiences in sleep or in transition to or from sleep
75
List 3 disorders of arousal (from non-REM sleep)
Confusional arousals
Sleepwalking
Sleep terrors
76
List 3 parasomnias usually associated with REM sleep
REM sleep behaviour disorder
Recurrent isolated sleep paralysis
Nightmare disorder
77
List 6 other types of parasomnias
```
Sleep-related dissociative disorder
Sleep enuresis
Sleep-related groaning
Exploding head syndrome
Sleep-related hallucinations
Sleep-related eating disorder
```
78
When do disorders of arousal typically occur?
When arising from slow wave sleep (is a mixed state between sleep and wakefulness)
Usuaully occurs in the first 1/3 of night
79
What factors may exacerbate disorders of arousal?
Factors which deepen sleep
| Factors which disturb sleep
80
How do disorders of arousal present?
Confusion when woken and mentation slow
| Complex activity possible
81
At what stage of life are disorders of arousal more common?
In childhood
82
Do disorders of arousal have a familial component?
Yes
83
What is the main DDx for a disorder of arousal?
Seizure disorder
84
List 8 points of management for disorders of arousal
```
Reassurance
Alter sleep environment for safety
Avoidance of precipitants
Treat stress
Sleep extension
Scheduled wakenings
Clonazepam/tricyclics
L-tryptophan for sleep terrors
```
85
Clonazepam
Benzodiazepine (also used for seizures)
86
What is the rationale behind the use of L-tryptophan for sleep terrors?
It is converted into serotonin
87
List 3 types of REM parasomnias
REM behaviour disorder
Frequent nightmares
Isolated sleep paralysis
88
Who is the typical demographic affected in REM behaviour disorder?
Elderly men predominantly (0.5% prevalence)
| Association with neurodegenerative disorders
89
What is REM behaviour disorder characterised by?
Dream enactment behaviour (often violent)
| Failure of REM atonia/locomotor quiescence
90
What different forms of REM behaviour disorder are there?
Idiopathic/secondary forms
91
What may precipitate the acute form of REM behaviour disorder?
Injury
CVA
SSRI
92
How is REM behaviour disorder managed?
Treat associated conditions
Stop causative medications
Consider use of clonazepam (80-90% respond), melatonin
