insomnia/sleep-wake disorder

4-6 cycles

how many sleep cycles does the average adult go through in a night?

beta waves (13-30 Hz)

EEG findings of alert, active metnal state

alpha waves (8-13 Hz)

EEG findings of relaxed wakefulness (eyes closed)

theta waves

EEG findings of N1 sleep (light sleep, easily aroused; hypnic jerks common

Sleep spindles, K-complexes

EEG findings of N2 sleep

N2 sleep

Largest proportion (~45-55% of total sleep); reduced heart rate & body temp

delta waves (slow wave sleep)

EEG waves associated with N3 sleep stage

N3 sleep stage

Deepest sleep, restorative; growth hormone secretion peaks; parasomnias (night terrors, sleepwalking) occur here

Beta-like waves (similar to awake), rapid eye movement, muscle atonia

EEG findings associated with REM sleep

REM sleep

what sleep stage?

Dreaming; increased brain O₂ use and limbic activity; variable HR/BP

↓ Total sleep time

↓ Slow-wave (deep) sleep

↑ Sleep latency (takes longer to fall asleep)

↑ Nighttime awakenings

↓ REM latency but overall less REM sleep

how does sleep change with aging?

takes longer to fall asleep

what does it mean to have increased sleep latency?

↓ REM latency but overall less REM sleep

how does REM sleep change with aging?

parasomnias

Abnormal behaviors such as nightmares or sleepwalking that occur during sleep.

insomnia disorder

Difficulty initiating or maintaining sleep, early awakening

-often associated with stress, depression, anxiety

Obesity, large neck circumference, hypertension

risk factors for obstructive sleep apnea

narcolepsy

Daytime sleep attacks, cataplexy, hypnagogic/hypnopompic hallucinations, sleep paralysis

hypocretin (orexin)

narcolepsy is associated with decreased ________ in CSF

narcolepsy

sleep-onset REM

restless leg syndrome

Uncomfortable leg sensations relieved by movement

-worse at night

iron deficiency or CKD

conditions linked to restless leg syndrome

periodic limb movement disorders

Involuntary leg movements during sleep causing arousals

-Seen in older adults, may cause daytime fatigue

NREM (night terrors/sleepwalking) vs REM (acting out dreams)

is NREM or REM sleep associated with parasomnias

circadian rhythm disorders

Sleep-wake mismatch (e.g., shift work, delayed sleep phase)

-Difficulty aligning sleep with social/work schedule

Insomnia disorder, circadian rhythm disorder, anxiety, stimulant use

DDx of difficulty falling asleep

insomnia, depression, sleep apnea, pain disorder

DDx of frequent awakenings/early morning awakenings

restless leg syndrome

restless, tingling legs before sleep relieved by movement

REM behavior disorder

acting out dreams/violent movements in sleep is associated with

Parkinson's syndrome

what syndrome is associated with REM behavior disorder?

sleep walking or night terrors

NREM parasomnia examples

sleep apnea, PLMD, depression

DDx of unrefreshing sleep despite full duration

Cognitive Behavioral Therapy for Insomnia (CBT-I)

Sleep hygiene education

Stimulus control (bed only for sleep/sex)

Sleep restriction and relaxation training

first line treatment for insomnia

zolpidem, zaleplon, eszopiclone

non benzo hyponotics used to treat insomnia short term

Ramelteon

melatonin receptor agonists

trazadone, low dose doxepin

sedating antidepressants used to treat insomnia short term

CPAP

first line for moderate to severe OSA

oral mandibular advancement device

devise for mild OSA or CPAP intolerant pts

central sleep apnea

sleep disorder with periods of interrupted breathing due to a disruption in signals sent from the brain that regulate breathing

-potential causes: heart failure, opioid use

Maintain safety (secure environment), avoid sleep deprivation, treat stress; low-dose benzodiazepine if severe

management of NREM parasomnias

Clonazepam (first-line), melatonin as alternative; screen for neurodegenerative diseases

management of REM behavior disorder

Reassurance, imagery rehearsal therapy, prazosin (for PTSD-related nightmares)

management of nightmares

Chronic pain, asthma, GERD, thyroid disorders, nocturia

medical risk factors for insomnia

Stimulants, steroids, antidepressants (e.g., SSRIs), decongestants

medications that increase risk of insomnia

depression or anxiety

insomnia often coexists with

hypertension, arrhythmias, and metabolic syndrome.

untreated OSA increases risk for

hyperthyroidism, diabetes (nocturia, neuropathic pain)

endocrine disorders associated with insomnia

>3 months, ≥3 nights/week

define chronic insomina

-suspected OSA

-PLMD suspected

-narcolepsy

-parasomnias

-failure of standard insomnia therapy

indications for pollysomnography

polysomnography followed by multiple sleep latency test

diagnostic tests for narcolepsy

EEG → sleep stage architecture

EOG → eye movements (REM detection)

EMG → muscle tone and leg movements

ECG / Pulse oximetry → oxygen desaturation, apnea events

Respiratory effort sensors → distinguish obstructive vs central apneas

components of a sleep study

Increased sleep latency (takes longer to fall asleep)

Reduced total sleep time and efficiency

Increased wake after sleep onset (WASO)

Normal architecture otherwise, unless comorbid disorder present

PSG findings of insomnia

Bind selectively to the benzodiazepine site on GABA-A receptor (α1 subunit) → enhance inhibitory GABA activity

MOA of non-benzo hypnotics

non benzo hypnotics (zolpidem, zaleplon, eszopiclone)

Short half-life → less hangover; best for sleep onset/maintenance depending on agent

benzodiazapenes

Non-selective GABA-A agonists → increase frequency of chloride channel opening → CNS depression

Effective but ↑ tolerance, dependence, and withdrawal risk

risks associated with benzo use to treat insomnia

Ramelteon

Agonist at MT1 and MT2 receptors in the suprachiasmatic nucleus → regulates circadian rhythm

suvorexant, lemorexant

block orexin (hypocretin) receptors OX1R & OX2R, preventing wake-promoting signals

Histamine H1 blockade (doxepin); 5-HT2 and α1 blockade (trazodone)

MOA of the sedating antidepressants (doxepin, trazadone, mirtzapine)

Dizziness, headache, complex sleep behaviors (sleep-driving, eating), tolerance

-avoid with alcohol or other CNS depressants

common side effects of the Z-drugs

avoid in elderly (↑ fall/cognitive risk), pregnancy, or substance use history

contraindications of benzos

Somnolence, sleep paralysis, abnormal dreams

common side effects of orexin antagonists

avoid in narcolepsy or OSA

contraindication to orexin antagonists

weight gain

side effect of mirtazapine (sedating antidepressant)

It may help induce sleep but fragments REM sleep later.

why shouldn't you have alcohol near bedtime?