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Sleep Disorders

I. Introduction

- 12%-15% of all people have experienced serious sleep problems

- Not all sleep problems are insomnia

- The elderly receive almost 40% of all sedative-hypnotic prescriptions

- Several classifications of sleep disorders exist

II. Classification of Sleep Disorders

- Primary Sleep Disorder: sleep disorder is the primary or only manifestation of the problem

- Secondary Sleep Disorder: sleep disturbance is pan of a larger symptom complex

- Parasomnias: involve activities that would be more or less normal if performed during wakefulness, but are performed during sleep

III. Classification of Sleep Disorders

- Disorders of initiation and maintenance of sleep (DIMS)

- Disorders of excessive sleep (DOES)

- Disorders of the sleep-wake cycle

- Parasomnias

IV. Methods Used to Investigate Sleep Disorders

- Interviews

- Sleep diaries

- Questionnaires

- Polygraphy

- Visual observation

V. Survey Data of Sleep in the Elderly

- Increased time in bed

- Increased nocturnal awakening

- Decreased total sleep time

- Increased sleep onset latency

- Dissatisfaction with their sleep

- Daytime fatigue

- More frequent napping

VI. History of Sleep

- Previously thought to be a uniform state

- 1935: EEG changes noted (Loom/s)

- 1953: REM stage noted (Aserinsky & Kleitman)

- 1955: REM linked to dreaming (Dement & Kleitman)

VII. Sleep Stages-- NREM: orthodox sleep; the "S-state"

- Stage 1: transition phase, low voltage mixed frequency EEG (3-7 eps), 5%-10% of total sleep time (TST)

- Stage 2: sleep spindles (12-14 cps, 1/2-2 see) and K complexes, 40%-50% of TST

- Delta sleep: >20% waves with frequency 1/2-2 cps or slower, amplitude 75 uv peak to peak, 20%-30% TST. Sleep Stages-REM: paradoxical sleep, the "D-state"

- Alternates with NR.EM at 90-minute intervals

- Decreased muscle tone

- High incidence of sequential dream recall if awakened

- Low voltage, fast EEG with sawtooth waves

- Increased penile turgidity

- Increased cerebral blood flow

- Increased oxygen consumption

IX. Sleep Cycles

- First cycle progression: relaxed wakefulness (alpha waves) - stage 1 » stage 2 » delta (30-45 min after sleep onset) » stage 2 » REM (lst REM usually 70-90 rain after sleep onset for approximately 5 rain)

- Second cycle progression: starts when stage 2 recurs after 1st REM stage

- Stage 2 and REM alternate at 90 rain cycles

- Delta sleep is rare in later cycles

- Delta sleep is "deepest" sleep

X. Circadian Rhythm

-An innate endogenous rhythm of bodily functions

- Rhythm trained by environmental cues (Zeitgebers, eg, clocks, alarms, sun)

- Usually a 25-hour rhythm

- Adjustments to shift work take approximately one week

- The rhythm can be manipulated behaviorally; can force only wakefulness, not sleep

XI. Neurological Basis of Sleep

- 1890: (Mauthner)--speculated that area bear nucleus of 3rd cranial nerve related to sleep induction based on postmortem exams of patients with encephalitis and sleepiness

-1935: (Bremer)-encephale isole, cerveau isole, concluded that junction between diencephalon and brain stem crucial to sleep and wakefulness

-1949: (Momzzi & Magoun)--proposed existence of reticular activating system (RAS) for maintaining arousal

-1974: (Hobson)--wake-sleep-REM depends on 3 neurological systems

XII. Hobson-McCarley Model

-Wakefulness: maintained via activity in the ascending RAS

- Sleep: need both active hypnagogic sleep system and low activity in RAS

- REM: active involvement of nucleus ceruleus and gigantocellular field

XIII. Biochemical Basis of Sleep

- Norepinephrine: lesions of, noradrenergic neurons (locus ceruleus) result in decreased EEG signs of wakefulness and decreased REM

- Serotonin: lesions at serotonergic neurons (raphe nuclei in cats) result in insomnia relieved by treatment with serotonin precursors, eg, L-tryptophan administration decreases sleep latency

XIV. Sleep Lab Studies in the Elderly

- Show marked reduction in NKEM stages 3 and 4 (delta)

- Show marked reduction in sleep efficiency

- Show increased number of awakenings after sleep onset

- Show increased daytime sleepiness

- Show a longer adjustment time to sleep-wake schedule changes

XV. The Need for Sleep

- Not all people need the same amount

- We can decrease our need for sleep

- Sleep deprivation results in fatigue, irritability, paranoia

- Selective KEM deprivation results in REM rebound

XVI. Sleep Hygiene

-Exercise: athletes have more delta sleep

- Environment: unfamiliar surroundings, uncomfortable sleeping surfaces, noise and changes in temperature disrupt sleep

- Food: weight gain is associated with long uninterrupted sleep, while weight loss is associated with short fragmented sleep

- Sedative-hypnotics often worsen sleep

XVII. Primary Sleep Disorders

- Narcolepsy

- Sleep apnea

- Primary insomnia

- Primary hypersomnia

- Nocturnal myoclonus: stereotyped twitches every 2040 seconds

- Restless legs syndrome: 1/3 familial, a pre-sleep problem

- Nourestorative sleep: chronic alpha intrusion

- Pseudoinsomnia: claims of little sleep despite observation of sleep

- Periodic hypersomnia

- Kleine-Levin syndrome: increased sleepiness and appetite, mostly in young males

- Neutral state syndrome: excessive daytime sleepiness, automatic behaviors, microsleeps

- REM interruption insomnia

- Painful nocturnal erections

XVIII. Narcolepsy

- Sleep attacks: brief, 10-15 min, irresistible, and may occur in inappropriate circumstances

- Cataplexy: transient weakness while conscious, triggered by emotions

- Sleep paralysis: upon falling asleep or awakening, broken by touch, respiration not affected

- Hypnagogic hallucinations

- Pathophysiology: a disorder of immediate REM onset

XIX. Sleep Apnea

- Diagnosed: by having >30 apneic episodes during seven hours of REM and NREM sleep

- Symptoms: excessive daytime sleepiness, snoring, decreased attention, irritability, depression, and abnormal behaviors during sleep

- Signs: obesity, hypertension

- Types: central, upper airway, mixed

XX. Secondary Sleep Disorders: Medical

- Neurological disorders: disruption of the sleep-wake-REM systems

- Thyroid disorders: hyper » fragmented sleep; hypo » increased sleepiness and decreased delta

- Renal insufficiency: short, fragmented sleep

- Stimulants: insomnia

- Starvation: insomnia

- Pain: insomnia

- Sleep-exacerbated disorders: e.g., paroxysmal nocturnal dyspnea

- Iatrogenic problems: use of hypnotics

XXI. Considerations in Prescribing Hypnotics to the Elderly

- Consider changes in absorption, distribution, and elimination; in general, decrease the dose by 30%-50%

- Beware of the effect on sleep apnea

- Consider long-lasting effects on daytime performance and alertness

- The elderly have twice the incidence of adverse side effects and drug interactions

XXII. Evaluation of Hypnotic Agents

- How well does the drug work initially?

- How long does the drug work?

- How good is the daytime performance?

- How good is sleep after chronic use of the drug?

- What happens when the drug is discontinued?

XXIII. Sleep Medications

- Benzodiazepines: effective, fatal OD is rare

- Barbiturates, glutethimide, ethchlorvynol: potentiate liver enzymes; high risk of abuse

- Antihistamines: potentiate anticholinergic agents; relatively safe

- Chloral hydrate: affects protein binding

- Tricyclic antidepressants: non-specific; low margin of safety

- Antipsychotics: risk of tardive dyskinesia

- Over-the-counter agents: scopolamine causes grogginess

XXIV. Secondary Sleep Problems: Psychiatric

- Depression: early morning awakening; reduced REM latency

- Manic-depressive illness: decreased % REM sleep with mania

- Schizophrenia: sleep worse in acute phase

- Alcoholism: decreases REM and ages sleep pattern

- Anxiety: causes pre-sleep worry

XXV. Secondary Sleep Problems: Behavioral Problems

- Conditioned insomnia

- Internal arousal

- Disturbance of sleep-wake rhythm

- Self image and sleep phobia

XXVI. Parasonmias: Types

- Somnambulism: sleepwalking; delta stage; not usually associated with dreaming; low levels of arousal; amnestic on arousal

- Night tenors: extreme autonomic arousal

- Enuresis: bedwetting; predominantly NREM; outgrown

- Nocturnal bruxism: teeth grinding; often follows an alerting response

- Violent rhythmic movements during sleep

XXVII. Parasornnias: Characteristics

- More common in children

- Tend to occur early in the night

- An individual may show more than one type

- Individuals are usually amnestic for an episode

- Difficult to arouse during an episode

XXVIII. Sleep-Wake Disorders in the Elderly

- Sleep apnea is common: 35% without sleep complaints have it; 50% of all elderly referred to sleep centers have it

- Periodic leg movements increase with age

- Sleep pathology related to drugs, alcohol, and chronic medical illness increases

- Daytime sleepiness is more common

- Sleep problems in association with depression increase

- Circadian rhythm disturbances increase

XXIX. Excessive Daytime Sleepiness

- Narcolepsy

- Sleep apnea

- Kleine-Levin syndrome

- Neurological disorders

- Metabolic abnormalities

- Toxins

- Drugs

XXX. Questions to Ask Related to Excessive Daytime Somnolence

- Are there unusual muscular experiences?

- Is there snoring?

- What medications are being used?

XXXI. Insomnia

- Primary or idiopathic

- Psychiatric disorders

- Environmental problems

- Phase shifts

- Dream-related

- Sleep apnea

- Restless legs syndrome

- Nocturnal myoclonus

- Oversleeping

- Drug-related

- Neurological

- Medical

XXXII. Questions to Ask When Insomnia is Present

- Are there medical problems?

- Are there psychiatric problems?

- Are there behavioral problems?

- Does wakefulness occur every 90 minutes?

- Does insomnia really exist?

- Has the problem always existed?

XXXIII. Factors that Destroy Sleep

- Excessively noisy surroundings

- Excessively hot rooms

- Chronic use of hypnotics

- Caffeine in the evening

- Alcohol before bedtime

- Chronic use of tobacco

XXXIV. Factors that Improve Sleep

- Sleep only until refreshed

- Establish regular arousal time

- Maintain steady, daily exercise

- Eat light bedtime snack

- Read in bed instead of brooding