Sleep Science and Stages Overview

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Questions and Answers

What is the primary characteristic of REM sleep?

Decreased heart rate and respiratory rate

Deep sleep associated with protein synthesis

Inactivity of all voluntary muscles except extraocular muscles (correct)

Slow, regular heart rate and regular respiration

What primarily happens during N3 sleep?

Transition from wakefulness to sleep

Release of cortisol into the bloodstream

Sudden bursts of sympathetic nervous system activity

Restoration functions like protein synthesis and immune function (correct)

How does sleep change with age?

Total sleep time increases, and N3 sleep increases

Number of arousals decreases significantly

Quality of sleep remains constant with age

N3 sleep declines, while N1 sleep increases (correct)

Which stage of sleep is primarily characterized by sleep spindles and k-complexes on EEG?

N2 Signup and view all the answers

What physiological change occurs during REM sleep?

Irregular heart rate with rapid fluctuations Signup and view all the answers

What is the duration of N1 sleep?

15-30 minutes Signup and view all the answers

Which statement about cortisol levels during sleep onset is correct?

Cortisol concentrations are lowest at sleep onset Signup and view all the answers

What is the primary purpose of the Restorative Theory of Sleep?

To restore tissues and prepare for the next day Signup and view all the answers

How many hours of sleep does the average person typically require each night?

8 hours Signup and view all the answers

What is a significant risk associated with poor sleep?

Increased mortality Signup and view all the answers

Which of the following sleep parameters measures the time taken to transition from wakefulness to sleep?

Sleep onset latency (LSO) Signup and view all the answers

What does the term 'sleep efficiency' (SE) describe?

Total sleep time divided by time spent in bed Signup and view all the answers

Which of the following is an advantage of the Adaptive Theory of Sleep?

Increases survival Signup and view all the answers

What effect can poor sleep have on individuals with ADHD?

Worsening of symptoms Signup and view all the answers

What does the Multiple Sleep Latency Test (MSLT) measure?

The tendency to fall asleep at various times during the day Signup and view all the answers

What health risk is associated with poor sleep due to hormonal changes such as increased cortisol and insulin resistance?

Obesity Signup and view all the answers

Which benzodiazepine is typically used for short-term treatment of insomnia with the lowest starting dose for elderly patients?

Triazolam Signup and view all the answers

What is a common adverse effect associated with both benzodiazepines and non-benzodiazepines?

Respiratory depression Signup and view all the answers

Which medication is NOT recommended during breastfeeding due to potential infant sedation issues?

Temazepam Signup and view all the answers

What is the maximum duration for which zaleplon is typically effective?

< 4 hours Signup and view all the answers

What side effect may occur specifically with zolpidem in pediatric patients?

Hallucinations Signup and view all the answers

What is the normal range of mean sleep latency in the Multiple Sleep Latency Test?

Greater than or equal to 15 minutes Signup and view all the answers

Which of the following statements is true regarding the Maintenance of Wakefulness Test?

It determines if sleepiness affects driving or work ability. Signup and view all the answers

Which of the following is a risk factor for insomnia disorder?

Financial work stress Signup and view all the answers

In regard to the Epworth Sleepiness Scale, what does a score of 10-15 indicate?

Very or excessively sleepy Signup and view all the answers

What does the Insomnia Severity Index (ISI) primarily measure?

The severity of insomnia symptoms Signup and view all the answers

Which neurotransmitter is associated with promoting wakefulness?

Dopamine Signup and view all the answers

Which of the following disorders lasts more than 4 weeks?

Long-term insomnia Signup and view all the answers

What is the primary focus of treatment goals in managing insomnia?

Improvement in sleep quality and reduction of daytime impairments Signup and view all the answers

Which of the following is NOT a physiological parameter measured during polysomnography?

Body temperature Signup and view all the answers

What condition is indicated by abnormal REM sleep during two or more naps?

Narcolepsy Signup and view all the answers

What should be done if you are unable to fall asleep within 20-30 minutes?

Leave the bed and perform a relaxing activity Signup and view all the answers

Which of the following is NOT recommended as part of sleep hygiene?

Drinking large quantities of liquids before bedtime Signup and view all the answers

How often should a person ideally exercise to improve sleep hygiene?

Three to four times weekly Signup and view all the answers

What is the main advantage of Cognitive Behavioral Therapy (CBT) over pharmacotherapy in treating chronic insomnia?

It leads to sustained improvement even after discontinuation Signup and view all the answers

What should you avoid immediately before going to bed?

Engaging in heavy exercise Signup and view all the answers

Which activity is beneficial to schedule during the day in relation to sleep?

Worry time Signup and view all the answers

In managing sleep hygiene, what is the recommended approach to temperature in the bedroom?

Avoid temperature extremes Signup and view all the answers

What effect does regular use of benzodiazepine receptor agonists have on chronic insomnia?

Effective only during treatment Signup and view all the answers

Which substance should be reduced to improve sleep hygiene?

Caffeine Signup and view all the answers

What is a suggested action if sleepiness does not occur after trying to fall asleep?

Leave the bed and do something else Signup and view all the answers

Study Notes

Sleep-Wake Disorders

A presentation on sleep-wake disorders.
Objectives of the presentation include: defining sleep disorders, understanding differences between various sleep disorders, diagnosis and treatment of sleep disorders, reviewing therapy plans and selecting appropriate therapy for each patient.

Stages of Sleep

Non-REM sleep accounts for 75% of total sleep.
REM sleep accounts for 25% of total sleep.
The four stages of sleep are presented, illustrating the transition from falling asleep to REM sleep.

Non-REM Sleep

N1: Transition from wakefulness to deeper sleep, lasting 15-30 minutes.
N2: Intermediate sleep, featuring sleep spindles and K-complexes on EEG.
N3 (and sometimes N4): Deep sleep (delta sleep), characterized by delta waves on EEG, and crucial for restoration (e.g., protein synthesis, wound healing, immune function).

REM Sleep

Characterized by inactivity of voluntary muscles (except extraocular muscles).
Features rapid eye movements and dreaming.
Two states: phasic (sympathetic nervous system bursts, blood pressure & heart rate fluctuations) and tonic (parasympathetically driven, decreased EEG amplitude, atonia).

Physiological Changes During Sleep

Autonomic activity: non-REM sleep features slow, regular heart rate and respiration rates, and blood pressure, while REM sleep displays irregular fluctuations.
Neuroendocrine activity: cortisol levels lowest at sleep onset, growth hormone released during delta sleep; melatonin secretion highest during sleep, suppressed by light.
Body temperature: lowest in early morning REM sleep, shows a cooling trend from non-REM to REM stages.

Sleep Changes with Age

Sleep quantity and quality decline with age.
Sleep stage N3 (deep sleep) decreases.
Sleep stage N1 (light sleep) increases.
The number of arousals and wakefulness also increases.

Theories of Sleep

Restorative theory: tissues are restored and prepared for the following day.
Adaptive theory: increases survival by minimizing metabolic processes during inactivity.
Energy conservation theory: low metabolic rate during sleep conserves energy.
7 hours of sleep might be optimal for health.

Risks of Poor Sleep

Increased mortality.
Increased heart attacks.
Increased accidents (similar to alcohol impairment).
Obesity (increased cortisol, insulin resistance).
Worsened pain conditions.
ADHD symptomatology.

Sleep Studies: Measurement of Sleep and Sleepiness

Polysomnography (PSG): measures various physiological variables (brain activity, breathing, airflow).
Multiple sleep latency test (MSLT): measures daytime sleepiness.
Maintenance of wakefulness test (MWT): measure how long one can stay awake.

Sleep Parameters

Sleep onset latency (SOL): time to fall asleep.
Latency to persistent sleep (LPS): time from lights off until 10 minutes consistent sleep.
Total sleep time (TST): total time spent asleep.
Wake time after sleep onset (WASO): time awake during the night.
Sleep efficiency (SE): ratio of TST to total time in bed (normal SE is >85%).

Polysomnography

Simultaneous recording of physiological variables with electrodes.
Measurements include: airflow, breathing effort, oxygen saturation, leg movements, ECG, and body position.

Multiple Sleep Latency Test (MSLT)

Objective measure of daytime sleepiness.
Measures the response to 5 opportunities, observed across 20-minute naps.
A latency below 5 minutes indicates severe sleepiness.

Maintenance of Wakefulness Test (MWT)

Measures the ability to stay awake.
Patients remain awake in a darkened room for as long as possible.

Standardized Rating Scales

Pittsburgh Sleep Quality Index (PSQI): assesses sleep quality.
Epworth Sleepiness Scale (ESS): measures daytime sleepiness.
Stanford Sleepiness Scale (SSS): measures daytime sleepiness.
Insomnia Severity Index (ISI): measures the severity of insomnia.
Dysfunctional Beliefs and Attitudes about Sleep Questionnaire (DBAS): measures insomnia-related beliefs.

Insomnia Severity Index (ISI)

7-item scale used to assess the severity of the Insomnia experience.
Range 0 to 28 with scoring and interpretation criteria provided.

Pittsburgh Sleep Quality Index (PSQI)

A validated self-report questionnaire to evaluate sleep quality.
Questions covering various aspects of sleep habits are asked.

Epworth Sleepiness Scale

Self-reported scale measuring daytime sleepiness.
Measures responses to 8 standardized scenarios.

Treatment Goals

Improve sleep quality and time.
Improve daytime impairments (e.g., energy, attention, memory).
Reduce sleep latency and wakefulness after sleep onset.
Improve symptomatic symptoms (e.g., fatigue).
Increase total sleep time.

Sleep Disorders

Insomnia disorder
Narcolepsy
Circadian rhythm sleep-wake disorder
Hypersomnia
Breathing-related sleep disorder
Rapid eye movement sleep behavior disorder
Restless legs syndrome
Nightmare disorder
Sleep terror disorder
Sleepwalking disorder

Insomnia Disorder

Subjective report of sleep initiation, duration, consolidation, or quality difficulties.
Despite adequate sleep opportunities, it results in daytime impairment.

Transient/Short Term/Long Term Insomnia

Timeline classification of insomnia based on duration.

Risk Factors for Insomnia

Situational factors (travel, stress).
Medical conditions (pain disorders).
Psychiatric factors (moods disorders).
Pharmacologically induced factors (medication use).

Neurotransmitter Pathophysiology

Wake-promoting substances: norepinephrine, acetylcholine, histamine, dopamine, orexin.
Sleep-promoting substances: GABA, adenosine, melatonin.

Signs and Symptoms of Insomnia

Difficulty falling asleep.
Difficulty maintaining sleep.
Frequent awakening.
Waking up too early.
Excessive daytime sleepiness.
Difficulty concentrating.
Memory impairment.

Nonpharmacological Treatments for Insomnia

Stimulus control procedures: establish regular sleep schedule, avoid daytime naps, and relaxing activities before bed.
Sleep hygiene recommendations: exercise regularly, create a comfortable sleep environment, avoid alcohol, caffeine, and nicotine before bed, and relaxed bedtime routine.

Pharmacological vs Nonpharmacological Treatment

Pharmacotherapy (often short-term; effective during treatment duration).
Cognitive Behavioral Therapy (CBT) (often more sustained improvement).

Pharmacological Treatment for Insomnia

Short-to-intermediate acting benzodiazepine receptor agonists or melatonin receptor agonists.

Benzodiazepines

Medication (drugs) used to treat insomnia, with approved FDA uses, doses, and durations.

Benzodiazepine receptor agonists (BzRAs)

Medication (drugs) used to treat insomnia; specific medications, approved FDA uses, doses, and durations are provided.
(BzRAs) (medication) include specific types and their durations of use, approved by the FDA.

Adverse Events from Sleep Medications

Benzodiazepines: CNS depression, tolerance, rebound insomnia, psychomotor impairment, respiratory depression, paradoxical reactions, sleep-related behavior.
Non-benzodiazepines: headache, next-day somnolence, sleep-related behavior, hallucinations, unpleasant taste.

Pregnancy/Lactation Considerations

Benzodiazepines and Non-benzodiazepines (medication) have potential risks during pregnancy and lactation.

Melatonin Receptor Agonist (Ramelteon)

Short to intermediate acting.
Used to treat sleep-onset insomnia.
Maximum effects may take up to three weeks.
Potential concerns, including sleep-related activities, abnormal thoughts, and worsening depression in sensitive patients.

Doxepin

Low-dose TCA/selective H1 antagonist activity.
Sleep maintenance medication; is taken with a high-fat meal and can delay Tmax by about 3 hours.
Has CYP2C19 interactions.
Dosage: adults (6 mg); elderly (3 mg).
Contraindications include: severe urinary retention, untreated narrow-angle glaucoma, and severe sleep apnea.

Suvorexant

Orexin receptor antagonist.
Taken 10 mg (sometimes 20 mg) nightly, at least 7 hours before bedtime.
Used for treating insomnia.
Contains potential interactions with CYP3A4 and may induce similar adverse sleep behaviors.

Antidepressants

Used in reduced dosages for treating insomnia.
Not FDA approved for insomnia treatment.

OTC Products

Antihistamines (diphenhydramine, doxylamine): potential anti-cholinergic effects, and possible tolerance after long durations.
Valerian: promotes GABA activity, and has inconsistent effects on sleep latency.
Melatonin: promotes melatonin; shows little effect on sleep latency / duration.

Duration of Treatment for Insomnia

Initial treatment period (generally 2-4 weeks).
Continuous or ongoing therapy (visits monitored), if chronic insomnia is present.

Discontinuation of Sleep Medications

Tapering of dose and frequency of use (avoiding rebound insomnia and withdrawal).
Possible recurrence or worsening of symptoms; physical or psychological withdrawal reactions.

Narcolepsy

Irresistible attacks of refreshing sleep nearly daily.
Excessive daytime sleepiness.
Cataplexy (sudden loss of muscle tone).
Abnormal manifestations of REM sleep (hallucinations, sleep paralysis).

Treatment of Excessive Daytime Sleepiness (EDS)

Naps (scheduled).
Modafinil or other medications (careful with CNS/cardiovascular patients).
Methylphenidate/amphetamine may cause more side effects than Modafinil.
Use caution in cardio/cerebrovascular disease or seizures.

Treatment of REM-Associated Effects

Cataplexy: sodium oxybate (FDA approved, abuse risk).
Unapproved options include TCAs, SSRIs, and SNRIs, and small-dose selegiline.

Circadian Rhythm Sleep-Wake Disorder

Misaligned sleep-wake cycles with societal norms.
Napping throughout the 24-hour period.
Potentially caused by shift work, jet lag, or substance abuse.

Melatonin Receptor Agonist (Tasimelteon)

FDA-approved for treating insomnia.
M1 and M2 receptor agonist; 20 mg/day.
Potential adverse reactions (especially in the elderly).
Limited potential for abuse.

Obstructive Sleep Apnea Hypopnea

Repetitive upper airway collapses during sleep.
Obvious symptoms such as snoring, and morning headaches.
Associated with obesity, large neck sizes, coexisting hypertension, or hypothyroidism.

Complications of Obstructive Sleep Apnea Hypopnea

Health risks (due to poor sleep quality).
Hypertension (often resistant to treatment), heart failure, and stroke.
Increased likelihood of cardiovascular events.

Obstructive Sleep Apnea Hypopnea Treatment

Continuous positive airway pressure (CPAP) or BiPAP therapy (first-line treatment).
Weight management.
Oral devices.
Surgical therapy (tracheostomy).
Modafinil (for symptom relief).

Rapid Eye Movement Sleep Behavior Disorder

Acting out dreams during sleep.
Violent movements possible in sleep.

Restless Legs Syndrome (RLS)

Feelings of restlessness, burning, tingling, and aches in legs, often before sleep onset.
Symptoms worsened in evenings/rest periods.
Can be worsened with low iron levels.

RLS Medication Options

Dopamine agonists (first line).
Anticonvulsants (first line if with seizures).
Hypnotic agents.
Opioids (not first-line treatment).

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Description

Explore the fascinating world of sleep with this quiz covering the various stages of sleep, including REM and N3, and how sleep changes with age. Test your knowledge on the physiological aspects of sleep and its impact on health, including factors such as sleep efficiency and the effects on ADHD. Understand the theories of sleep and the risks associated with poor sleep.