#3 Exam Normal Sleep and Sleep-wake disorders
REM sleep in normal persons
The body musculature resting muscle potential is lower
Narcolepsy
a type of human leukocyte antigen, HLA-DR2 is found in 90 - 100 % of patients with narcolepsy. Deficient in the neurotransmitter hypocretin, which stimulates appetite and alertness.
sleep hygiene
can include: keeping regular hours of bedtime and arousal, avoiding excessive caffeine, not eating heavy meals before bedtime, and getting adequate exercise
Melatonin
endogenous hormone produced by the pineal gland, which is linked to the regulation of sleep
REM sleep
pairs an atonic body with an active brain (capable of creating elaborate dream fantasies)
Characteristics of Insomnia Disorder
-occurs at least 3 nights per week, present for at least 1 month -Episodic: last at least 1 month, but less than 3 -Persistent: last 3 months or longer -Recurrent: Two or more episodes within 1 year
Short sleepers
-require fewer than 6 hours of sleep each night to function adequately - are generally efficient, ambitious, socially adept, and content
long sleepers
-require more than 9 hours of sleep each night to function adequately. - have more REM periods and more rapid eye movements within each period (REM density). -tend to be mildly depressed, anxious, and socially withdrawn.
Sleep deprivation
-with prolonged periods can lead to ego disorganization, hallucinations, and delusions.
Psychophysiological insomnia features
1)excessive worry about not being able to sleep 2)trying too hard to sleep 3)rumination 4)increased muscle tension when attempting to sleep 5)somatic manifestations of anxiety 6)being able to sleep better away from one's own bed 7)being able to fall asleep when not trying to
sleep is made up of
2 physiological states: 1)non-rapid eye movement (NREM) 2)rapid eye movement (REM)
Sleep
About 90 minutes after sleep onset, NREM yields to the first REM episode of the night. This REM latency of 90 minutes is a consistent finding in normal adults; shortening of REM latency frequently occurs with such disorders as narcolepsy and depressive disorders
role of norepinephrine in sleep
NE-containing neurons will cell bodies located in locus ceruleus play important role in controlling normal sleep patterns. drugs that increase the firing of NE containing neurons reduce REM sleep and increases wakefulness
indications for polysomnography
`0diagnosis of sleep-related breathing disorders 2)positive airway pressure titration and assessment of treatment efficacy 3)evaluation of sleep-related behaviors that are violent or may potentially harm the patient or bed partner.
apnea
a period of cessation of breathing for 10 seconds or more during sleep.
during REM sleep
almost every period in men is accompanied by a partial or full penile erection. this is used in sleep studies for diagnosis
A brief period of insomnia is usually associated with
anxiety; either as a sequela to an anxious experience or in anticipation of an anxiety-provoking experience. transient insomnia of this kind may be related to grief, loss, or almost any life change or stress. a psychotic episode or a severe depression sometimes begins with acute insomnia
additional reasons for polysomnography
atypical parasomnias, sleep-related problems secondary to neuromuscular disorders, periodic limb movement disorder, arousals secondary to seizure disorder, those with excessive daytime sleepiness or those who wake up gasping of choking should be referred.
wakefulness
both the body and the brain are active
NREM sleep
both the body and the brain are much less active
Role of acetylcholine (ACh) in sleep
brain ACh involved in production of REM sleep - disturbances in central cholinergic activity are associated with the sleep changes observed in MDD.
sleep state misperception (subjective insomnia)
by a dissociation between the patient's experience of sleeping and the objective polygraphic measures of sleep. diagnosed when a patient complains of difficulty initiating or maintaining sleep and no objective evidence of sleep disruptions is found. can represent a somatic delusion or hypochondriasis.
RLS
check ferritin levels and B12 due to iron or folic acid deficiency anemias causing this. Also thyroid disease check TSH. Diabetes, fibromyalgia, rheumatoid arthritis, and COPD
Persistent insomnia
composed of a fairly common group of conditions in which the problem has difficulty falling asleep or remaining asleep. associated with somatized tension and anxiety and a conditioned associative response. may complain of apprehensive feelings or ruminative thoughts that keep them awake.
NREM
composed of stages 1-4 most physiological functions are markedly lower than in wakefulness
polysmnography
continuous, attended, comprehensive recording of the biophysiological changes that occur during sleep.30-sec segment of the recording is an epoch. looks at brain wave activity, eye movement, submental electromyography activity, nasal-oral airflow, respiratory effort, oxyhemoglobin saturation, heart rhythm, and leg movements during sleep are measured,
Parasomnias
disorders of partial arousal - a diverse collection of sleep disorders characterized by physiological or behavioral phenomena that occur during or are potentiated by sleep.
Insomina
dissatisfaction with sleep quantity or quality associated with one or more of the following symptoms: difficulty in initiating sleep, difficulty in maintaining sleep and frequent awakenings or problems returning to sleep, and early morning awakening with inability to return to sleep.
role of dopamine in sleep
drugs that increase dopamine produce arousal and wakefulness dopamine blockers increase sleep.
polysomnogram for OSA
episodes of OSA in adults are characterized by multiple periods of at least 10 seconds in duration in which nasal and oral airflow ceases completely (an apnea) or partially (a hypopnea), while the abdominal and chest expansion leads indicate continuing efforts of the diaphragm and accessory muscles of respiration to move air through the obstruction
L-tryphtophan in sleep
essential amino acid needed by the body to produce serotonin; found in protein-based food and dietary proteins (eggs, poultry, milk). ingestion of large amounts increases sleep and reduces nocturnal awakenings. Defenciety reduces REM sleep.
Clinical features of OSA
excessive sleepiness, snoring, obesity, restless sleep, nocturnal awakenings with chocking or gasping for breath, morning dry mouth, morning headaches, and heavy nocturnal sweating. HtN, erectile failure in men, depression, heart failure, nocturia, polycythemia and memory impairment as a result of obstructive sleep apnea hypopnea.
medical conditions known to cause hypersomnia
head trauma, stroke, encephalitis, parkinson's disease, inflammatory conditions, tumors, genetic diseases, and neurogenerative diseases
role of melatonin and sleep
hormone secreted from the pineal gland is inhibited by bright light, so lowest concentrations during the day. the suprachiasmatic nucleus of the hypothalamus may act as the anatomical site of the circadian pacemaker that regulates melatonin secretion and the entrainment of the brain to a 24-hour sleep-wake cycle.
insomnia can be classified
how it affects sleep (sleep-onset insomnia, sleep maintenance insomnia, or early-morning awakening). Can also be classified according to its duration (transient, short term, and long term)
Narcolepsy signs
hypocretin deficiency as measured using CSF hypocretin-1 immunoreactivity values (less than or equal to one third of values obtained in healthy subjects tested using the same assay or less than equal to 100pg/mg). Low CSF levels of hypocretin-1 must not be observed in the context of acute brain injury, inflammation, or infection.
sleep walking and sleep terrors
involve momentary or partial wakeful behaviors suddenly occurring in NREM (slow wave) sleep
REM behavior disorder
involves a failure of the patient to have atonia (sleep paralysis) during the REM stage sleep. The result is that the patient literally enacts his or her dreams. Without this paralysis or with intermittent atonia, punching, kicking, leaping, and running from bed during attempted dream enactment occur.
Narcolepsy
is a condition characterized by excessive sleepiness, as well as auxiliary symptoms that represent the intrusion of aspects of REM sleep into the waking state.
NREM sleep in normal persons
is a peaceful state relative to waking. The pulse rate is typically slowed 5 - 10 bpm below the level of restful waking and is very regular. Respiration is similarly affected, and blood pressure also tends to be low, with few minute-to-minute variations. Episodic involuntary body movements are present, blood flow through most tissues and cerebral blood flow, is slightly reduced. Few if any REMs occur
cyclic nature of sleep
is regular - a REM period occurs about every 90-100 minutes during the night. The first REM period tends to be the shortest, usually lasting less than 10 minutes; later REM periods may last 15-40minutes. Most REM periods occur in the last third of the night, whereas stage 4 sleep occurs in the first third of the night.
REM
isolated sleep paralysis is the persistence of REM sleep atonia (sleep paralysis) into the wakefulness transition, whereas REM sleep behavior disorder is failure of the mechanism, creating paralytic atonia such that individuals literally act out their dreams.
Narcolepsy symptoms
most common is sleep attacks (cannot avoid falling asleep); Cataplexy sudden loss of muscle tone (jaw drop, head drop, weakness of the knees, or paralysis of all skeletal muscles with collapse; hypnagogic or hypnopompic hallucinations (vivid perceptual experiences, wither auditory or visual occurring at sleep onset or on awakening; sleep paralysis
The classic form of Narcolepsy
narcolepsy with cataplexy - characterized by the tetrad of symptoms 1)excessive daytime sleepiness 2)cataplexy 3)sleep paralysis 4)hypnagogic hallucinations. Abnormal sleep architecture in which REM sleep occurs soon after sleep onset both at night and during the day. Narcolepsy appears to be a REM sleep intrusion syndrome from the dysfunction of REM sleep generator gating mechanisms.
Role of serotonin in sleep
prevention of serotonin synthesis or destruction of the dorsal raphe nucleus of the brainstem, which contains nearly all the brain's serotonergic cell bodies, reduces sleep for a considerable time. Synthesis and release of serotonin by serotonergic neurons are influenced by the availability of amino acid precursors of this neurotransmitter, such as l-tryptophan
during REM sleep
pulse, respiration, and blood pressure are high during this sleep. brain oxygen use increases. thermoregulation is altered - a poikilothermic condition (a state in which animal temp varies with the changes in the temp surround medium) prevails during this sleep.
EEG records
rapid conjugate eye movements that are the identifying feature of the sleep state (no or few rapid eye movements occur in NREM sleep); the EEG pattern consists of low voltage, random, fast activity with sawtooth waves; The EEG shows a marked reduction in muscle tone.
Obstructive Sleep Apnea Hypopnea
repetitive collapse or partial collapse of the upper airway during sleep. During an obstructive apnea episode, respiratory effort continues but airflow ceases due to loss of airway patency. a reduction in breathing for at least 10 seconds (Hypopnea)
Polygraphic measures during REM
show irregular patterns, sometimes close to aroused waking patterns. looks like an active waking state. which is why REM sleep is called paradoxical sleep.
REM
sleep is a qualitatively different kind of sleep, characterized by a high level of brain activity and physiological activity levels similar to those in wakefulness.
Sleep regulation centers
small number of interconnecting systems or centers that are located chiefly in the brain stem and that mutually activate and inhibit one another.
Idiopathic insomnia
start early in life; cause is unknown; possibly neurochemical imbalance in brainstem reticular formation, impaired regulation of brainstem sleep generators (raphe nuclei, locus ceruleus), or basal forebrain dysfunction.
polysomnography
test to monitor brain waves, muscle tension, eye movement, and oxygen levels in the blood as the patient sleeps
NREM sleep
the deepest portions occur in stages 3 and 4. if aroused during this time the person will be disoriented, and their thinking will be disorganized. Brief arousals from slow-wave sleep are also associated with amnesia. the disorganization during arousal from stage 3 or 4 may result in problems such as enuresis, somnambulism, and in state 4 nightmares and night terrors.
during REM sleep
the near-total paralysis of the skeletal (postural) muscles. Because of this motor inhibition, body movement is absent. Dreaming occurs and it the most distinctive feature of this sleep stage
Primary Insomnia
treated with Benzos, zolpidem, eszopiclone (Lunesta), zaleplon (Sonata) and other hypnotics. should only be prescribed for 2 weeks due to tolerance and withdrawal.
Psychophysiological insomnia
typically presents as a primary complaint of difficulty in going to sleep. may have gone on for years and denies associated with stressful periods. objects associated with sleep (bed or bedroom) become conditioned stimuli that evoke insomnia. also called conditioned insomnia.
sleepiness can be caused
use or abuse of sedative hypnotics, sedating antihistamines, sedating antidepressants, antiepileptics, neuroleptics, and opioid analgesics. can be provoked by withdrawal from traditional stimulants, caffeine, or nicotine.
multiple sleep latency test
used for diagnosing narcolepsy. beginning 2 hours after morning awakening, 20 minute nap opportunities are provided during which the patient is instructed to let himself or herself fall asleep and not resist falling asleep. Electroencephalographic, electro-oculographic, and submental electromyography activity is recorded to determine sleep stage. The latency to sleep is used to assess the level of sleepiness, and the appearance of REM sleep on two or more nap opportunities confirms narcolepsy.
stages of sleep defined by
visual scoring of 3 parameters:electroencephalogram (EEG), electro-oculogram (EOG), and electromyogram (EMG)
Primary insomnia
when the chief complaint is non-restorative sleep or difficulty in initiating or maintaining sleep, and the complaint continues for at least a month. the insomnia is independent of any known physical ro mental condition. both difficulty falling asleep and by repeated awakening.
