Sleep And Its Disorders

Question 1

Sleep Disturbance in Old Age

Answer 1

Parasomnias

Hypersomnia

Sleep Disordered Breathing: most deadly but not the most common

Insomnia: most common

Circadian Rhythm Sleep Disorders

Sleep related movement disorders: 2nd most common

Question 2

Epworth Sleepiness Scale

Answer 2

A scale intended to measure daytime sleepiness

• a short questionnaire
• 11+ is abnormal

Question 3

Sleep Studies

Answer 3

What info do they provide

• sleep duration
• sleep latency: how quickly they fell asleep
• sleep architecture: sleep stage distribution, seizures, EEG patterns, arousals
• Breathing patterns: apnea, hypopnea
• muscle movements: bruxism, limb movements (grinding teeth)
• body position
• behaviors awake and asleep: sleep walking, groaning, dream enactment, waking up and eating or using the phone, etc.

Question 4

Sleep Stages

Answer 4

• Wakefulness: alpha waves are relaxed wakefulness (occur as you close your eyes, open eyes and they go away)
• Stage 2: sleep spindles and K complexes
• Stages 3+4: delta waves
• REM: look a lot like wake

Distribution: (normal adult)
-NREM sleep: 80%
     Stage 1: 5%
     Stage 2: 55%
     Stage 3: 15%
-REM Sleep: 25%

Question 5

Normal Sleep

Answer 5

• sleep latency: 20-30 mins
• sleep progression: N3 dominant during the first third of the sleep period; and REM during the last 3rd
• Sleep is entered thru NREM sleep
• duration varies by age, but generally 7.5 hours nightly
• survival curve is U shaped; decreased survival with short (less than 5 hours) or long (over 9 hours) sleep
• W during sleep less than 5%
• REM recurs every 90 to 120 mins
• AHI < 5
• PLMI < 5
• Arousals increase with age (by age 40, people generally don’t sleep thru the night)

Question 6

Sleep Studies

Answer 6

-PSG (polysomnogram): Gold standard
Measures: EEG, EMG, EOG (eye movements), EKG, SpO2, resp., air flow, nasal pressure, body position and sometimes ETCO2
-Diagnostic
-split night: first part is diagnostic, 2nd part to treat
-therapeutic
-should be performed during pt’s NORMAL sleep time

Question 7

Obstructive Apnea

Answer 7

Cessation of airflow for 10+ seconds with continued effort in thoraco-abdominal signals

-pt is trying to breathe

Question 8

Central Apnea

Answer 8

Cessation of airflow for 10+ seconds without demonstrable effort; diaphragmatic and intercostal EMG electrodes often indicate effort not picked up by surface sensors

Question 9

Mixed Apnea

Answer 9

Initial central component followed 2 to 3 obstructed breathes

Question 10

RERA

Answer 10

Respiratory Effort Related Arousals

Question 11

AHI (Apnea-hypopnea index)

Answer 11

number of both types of events per hour of sleep

Question 12

Arousal

Answer 12

Increased EEG frequency lasting 3 seconds

Question 13

Limb Movements

Answer 13

Defined by amplitude and duration

Question 14

Periodic Limb Movements

Answer 14

Repetitive muscle twitches in the extremities occurring within 5 to 90 seconds of on another, with at least 4

Question 15

REM w/o Atonia

Answer 15

Absence of the expected loss of EMG tone in REM sleep

Question 16

RDI (respiratory disturbance index)

Answer 16

AHI plus RERAs

Gov. Has decided to only pay for tx for apnea and not RERA

Question 17

PLMI (periodic limb movement index)

Answer 17

Number of limb movements per hour of sleep

Question 18

PLMAI (periodic limb movement arousal index)

Answer 18

Number of limb movements with arousals per hour of sleep

Question 19

Sleep Studies (types)

Answer 19

HSAT (home sleep study): airflow, thoracoabdominal movements, SpO2, HR

PAT: peripheral arterial tonometry (if they’re positive then apnea is here. Recommend only for people with moderate to severe likelihood for having obstructive apnea)

—these are screening studies with a false negative rate of 17% in the moderate to high risk population

Actigraphy: light and motion; surrogates for sleep time

Question 20

Indications for a home sleep study

Answer 20

• high probability for mod to severe OSA
• absence of comorbid heart, lung, or neurologic disease
• not indicated for other sleep disorders (central apnea, parasomnias, PLMS, insomnia, etc.)

pt must be able to apply the device

-no EEG, no muscle movement. All there is, is breathing. Need a 4% drop in saturation to say something is wrong

Question 21

Snoring

Answer 21

-At age 35: 15% of F and 35% M snore
-At age 55: 35% of F and 65% M snore
—-not sure if primary snoring is a disorder
A study looked at a group of men who didn’t have sleep apnea
—snoring far more likely to have carotid stenosis. Something specific to the carotid and not the femoral artery
IMPORTANT: studies showing increase risk of stroke for people who are heavy snorers. Vibration of the snoring that causes small tears and stuff

Question 22

Insufficient Sleep

Answer 22

• chronic sleep deprivation due to inadequate time for sleep
• over scheduling activities
• computers, gaming, exercise close to bedtime
• work, childcare responsibilities

Question 23

Meds

Answer 23

Opioids
Myorelaxants
DA agents
Anti-hypertensives
Antidepressants
Antiepileptics
Alcohol/illicit drug use

Question 24

Obstructive Sleep Apnea (in detail)

Answer 24

• most common type of SDB
• muscles that control the tongue and soft palate relax causing the airway to narrow and close
• patient tries to breathe but can’t due to airway obstruction
• patient stops breathing for more than 10 seconds

-pure OSA: responds very well to simple nasal CPAP (provided one keeps the deleterious effects of positive pressure on cardiac output in the dehydrated patient in mind)

Associated with dec. life expectancy: people who stop breathing 20 or more times in an hour (life expectancy cut in half)

Increased risk for:

• cancer
• diabetes
• accidents
• cognitive dysfunction
• heart disease
• stroke
• HTN

Tx:
-positional therapy (some people only have it when sleeping on back)
-weight loss: thin people do have sleep apnea tho
-surgery: bariatric is most effective (80% of people still need CPAP after) and upper airway surgery works 20% of time
-Oral appliance
-CPAP: gold standard
It’s a pneumatic splint keeping the upper airway open

Question 25

Central Sleep Apnea

Answer 25

- patient makes no effort to breathe in thorax nor abdomen during apnea - patient stops breathing for more than 10 seconds - typical in severe heart failure patients - may be characterized by Cheyne-Stokes respiration (CSR) separated by periods of apnea or hypopnea - we also see it now in patients using methadone increased risk for: - cancer - heart disease - diabetes - accidents - cognitive dysfunction - HTN - stroke

Question 26

Narcolepsy

Answer 26

- characterized by rapid transitions from wake to REM - genetic predisposition: HLA DQB1*0602 highly associated with cataplexy - however, only 30% concordance with monozygotic twins - may be associated with recent strep infection and H1N1 Tetrad: - sleepiness: naps are short and refreshing - sleep paralysis: inability to move or speak during transitions from sleep to wake. May occur in normals - hypnogogic/hynopompic hallucinations: dreamlike experiences at sleep onset/offset - Cataplexy: suddenly loss of muscle tone triggered by strong emotion, particularly laughter - age of onset: usually between 15 and 25 - sleepiness is generally the presenting complaint (includes automatic behaviors like sleeping with eyes open: typing the same word or driving and you don't know how you got home) - diagnosis is made by PSG/MSLT (polysomnogram/multisleep latency test) - presence of cataplexy is pathognomonic Tx: -symptomatic: stimulants for sleepiness Sodium oxybate and/or antidepressants for cataplexy -Other disorders may coexist (e.g. REM behavior disorder, OSA, PLMD) -insomnia due to REM sleep fragmentation may be present

Question 27

Idiopathic CNS Hypersomnia

Answer 27

- familial 50% of time - age of onset is between 10 and 30 (usually in the 20s) - naps are prolonged and unrefreshing - Sleep drunkenness more likely with awakenings (can't wake up, in a fog) - nocturnal sleep tends to be prolonged Eval: - NO OTHER CAUSE of EDS-all other sleep pathology treated - 2 weeks of sleep logs +/- actigraphy - NPSG (nocturnal polysomnogram): NL - MSLT (multiple Sleep latency test): MSL less than or equal to 8, < 2 SOREMS

Question 28

EDS Associated with Treated OSA

Answer 28

-despite adequate PAP tx of OSA 50% of subjects demonstrate MSL <11 min 25% complains of EDS -etiology is uncertain but studies in mice suggest lesions of the RAS as a consequence of the apnea before it was treated Tx: Stimulants

Question 29

Restless Leg Syndrome (RLS)

Answer 29

-international RLS rating scale 1 Desire to move legs, often associated with abnormal leg sensations Symptoms worsen at rest partial of temporary relief with activity Worsening of sx's later in the day or night -IRRLS 2: 10 questions with sx rated from 0 to 4 -11% in primary care clinic have RLS Dx: - clinical based on Hx - PE noncontributory - PSG not indicated unless another Dx is also being considered - differentiate from nervous tapping, circulatory disorders and neuropathy - presence of PLMs increases specificity - associated with major depression and panic disorder - don't tx unless it's happening 3 or more times a week Tx: - Fe replacement for ferritin < 50 - DA agents - Benzodiazepines - Gabapentin - Narcotics

Question 30

Periodic Limb Movements (PLM)

Answer 30

- usually occur during sleep but may occur while awake - 5 or more movements lasting > 0.5 sec to <10 sec, occuring at intervals of 5 to 90 seconds -associated with dec. in survival in systolic HF and ESRD Tx: - gabapentin - DA agents - GABA receptor agonists - Narcotics - Fe if appropriate

Question 31

Circadian Rhythm Disorders

Answer 31

- delayed sleep phase - misalignment between endogenous and external clocks - habitual sleep times are delayed by 2+ hours relative to conventional times - subsequent sleep is normal - often associated with difficulty waking up at socially acceptable times -delayed sleep phase: Common among adolescents and young adults affecting 7-16% Genetic factors, shift work and travel across mult. Time zones may precipitate the disorder Tx: timed bright light exposure, chronotherapy ``` Advanced Sleep Phase Jet Lag (west to east travel most difficult) Shift work irregular sleep wake rhythm Free running rhythm (most pts are blind) ```

Question 32

Insomnia

Answer 32

Risk factors: - gender - age - marital status - employment status - race - underlying med/physical disorder - ENV factors ``` Primary: -predisposing factors: biologic -precipitating factors: social -perpetuating factors: compensatory behaviors Worry directed at sleep itself Individual attitudes conditional arousal ``` ``` CoMorbid: -associated with other disorders such as Depression Generalized Anxiety Substance abuse ADHD Dementia Medical disorders ``` DDx: - circadian rhythm disorder - phase delay - phase advance - shift work sleep disorder - non 24-hour sleep/wake syndrome - irregular sleep/wake pattern