Sleep Disorders Medicine

• Sleep disorders are common. The dangers from subsequent sleepiness parallels the activities of the individual. Recognizing the hazards and causes of sleep disorders allows for the institution of measures to avoid catastrophes.

I. INTRODUCTION

• Sleep

– basic human behavior

– required for life

– restorative

I. INTRODUCTION

• Sleep Disorders (insomnia/sleepiness)

– Very common:

• 40 million Americans have a sleep disorder

• National Sleep Foundation surveys/polls

– 1995: 49% USA with insomnia

– 2002: 58% weekly insomnia

II. BACKGROUND

• International Classification of Sleep Disorders:88 sleep disorders

• Dyssomnias

• Parasomnias

• Medical/Psychiatric

• Proposed

II. BACKGROUND

• Dyssomnias

– Circadian-Rhythm Disorders

• Shift Work Sleep Disorder

– Intrinsic Sleep Disorders

• Sleep Apnea

• Restless Legs Syndrome

II. BACKGROUND

• Shift Work

– Industrial revolution/24 hour work day

– work replacing sleep

– 20 million Americans non-traditional work schedules, conflict with biologic clocks

II. BACKGROUND

• Sleep Apnea:> 18 million

• Restless Legs Syndrome: 5% > 65 years

• ICSD, revised: Rochester , MN : American Sleep Disorders Association. 1997.

II. BACKGROUND

– NSF 2002 poll: average sleep

• 6.9 hours weekdays

• 7.5 hours weekends

• 8.0 hours/night (only 30%)

II. BACKGROUND

• Why is sleep important?

• Inadequate sleep = sleepiness “an unseen threat to public health”

• Sleepiness; potentially catastrophic

• Danger from sleepiness parallels nature of work

• Mitler. Principals and Practice of Sleep Medicine. 1994: p 453-462.

II. BACKGROUND

• Congressional Office of Technologic Assessment/Bureau of Labor Statistics on Shift Work;1991:

– 70 billion dollars/year

• Tasto: Health Conseq of Shiftwork. Project URU-4426, TechnicReport, Stanford Research Institute, 1978.

II. BACKGROUND

– Chernobyl /Three Mile Island/Exxon Valdez

– Libby Zion

• The Chernobyl Accident. Wash DC, US Gov Print Off, 1986. Three Mile Island . Ann NY Acad Sci 365:1981. Case study: Exxon Valdez. Time, 1989. The Libby Zion case. NEJM, 1988 Space Shuttle Challenger crash:

II. BACKGROUND

– Space Shuttle Challenger crash

• Presidential Commission

– Senior management < 2 hours sleep

– Decision to launch, non-mission factors

II. BACKGROUND

– NSF 1995 survey:

• 1/3 rd insomniacs fell asleep driving (10% MVA)

– NSF 9/01 poll:

• 20% fell asleep driving/1-year

• > 1/3rd shift workers drive to work sleepy every “day”

II. BACKGROUND

– U.S. Department of Transportation

• Drowsiness

• 100,000 MVAs/year

• 71, 000 injuries

• 1500 fatalities

• 12.5 billion dollars/year

• Tommy Atkins

II. BACKGROUND

• National Transportation and Safety Board: sleepiness and fatigue

– 40% heavy truck accidents

– 57% fatal heavy truck accidents

– 42,000 deaths, all forms transportation

– NTSB: Safety Study: Vol 1 and 2, 1990.

II. BACKGROUND

• Great Britain Study

– Sleep = 27% driving loss of consciousness

– Sleep = 83% fatal MVAs with loss of consciousness

II. BACKGROUND

• Human error catastrophes

– parallel natural sleep times

• Midnight - 6 am

• 1 - 3 pm

• MVAs peak early am and midafternoon

– Mitler. Sleep.11, 1988. NTSB: Safety Study, Vol 1-2, 1990. Us Congr Off Tech Assess: US Gov Print Office, 1988.

II. BACKGROUND

• Why are sleep disorders not being eliminated?

– NSF

• “The overwhelming majority of sleep disorder sufferers remain undiagnosed and untreated because of a lack of educational programs for primary care physicians and the general public”.

• William Dement study.

III. SPECIFIC SLEEP DISORDERS

• A. SHIFT WORK

– Tolerance to Shift Work determined by

• 1. Circadian factors (SCN)

• 2. Social Issues

• 3. Other underlying sleep disorders

– Wever. Int J Chronobiol. 1975. Czeisler. Science. 1982. Monk. Princ and Pract Sleep Med. 1994.

SHIFT WORK

• 1. Circadian Factors

– circadian demand for sleep

– biologic clock: Suprachiasmatic nucleus (SCN)

• SCN in hypothalamus of the brain

– circadian rhythms do not adjust instantly

• Aschoff. Chronobiologia. 1975

SHIFT WORK

• Humans

– 25 hour animals

• Holidays (easier to stay up later)

• Easier to adjust westbound travel

• Shift rotations adjust faster “forward”

– Wever. Springer Verlag. 1979. Aschoff. Chronobiologia. 1978. Czeisler. Science. Vol 217.p 460-463.

SHIFT WORK

• Individual variability

– “night owls” adjust better than “morning larks”

• less affected by time cues (sunlight etc.)?

• Longer free-running system; easier “forward” shift

– Hilderbrand. Int Arch Occup Env Health. 1979.

SHIFT WORK

• Difficulties adjusting (entraining)

– lack of time cues (zeitgebers)

• dark

• few social activities

• weekends

– Mon. Hum Factors. 1986.

SHIFT WORK

• Entrainment difficult in elderly

– tend to become “morning larks”

– circadian strength fragile

• Webb. Pergamon Press. 1981.

SHIFT WORK

• General effects of age on sleep and the biologic clock

– Biologic clock (suprachiasmatic nucleus: SCN)

• Anterior hypothalamus

• Advanced sleep-phase syndrome

– treat with sleep hygiene

– bright light therapy

– melatonin?

SHIFT WORK

• General effects of age on sleep

– Loss of slow wave/delta/refreshing sleep

• treat with increase core body temperature

• exercise/heat exposure

SHIFT WORK

• General effects of age on sleep

– increase psychological/medical disorders

– increased medication use

SHIFT WORK

• II. Social Issues

– 1. Parenting demands

– 2. Spousal demands

– 3. Social isolation

• “company towns” shift work better tolerated

– Wdderburn. Occup Psychol. 1967.

SHIFT WORK

• Coping strategies

– educate/recognize the problem

– individualize therapy

– determine if suited; owl/lark, young/old?

– Sleep hygiene

• consistent schedule, blackout blinds, etc.

SHIFT WORK

• Coping strategies

– bright light therapy

• entrains, enhance circadian adjustment

• > 5000 lux at work

• complete dark for 8 hour sleep period

– young volunteers entrain in a week

» Czeisler. NEJM. 1990.

SHIFT WORK

• Coping strategies

– hypnotics

• may improve quality/duration sleep period

• risk dependency/rebound insomnia outweigh benefit

• melatonin?

– Graeber. Princ and Pract Sleep Med. 1994. Walsh. Sleep. 1984.

III. SPECIFIC SLEEP DISORDERS

• Rule out other underlying sleep disorder

– B. Sleep Apnea

– C. Restless Legs Syndrome

IV. INVESTIGATION

• A. History

• B. Physical examination

• C. Sleep diary

• D. Operational definitions of sleepiness

• E. Subjective measurements of sleepiness

IV. INVESTIGATION

• A. History

– 1. History of Present Illness

• a. Sleep environment

• b. Bedtime routine

• c. Bedtime

• d. Sleep latency

• e. Quality of sleep

• f. Arousals

IV. INVESTIGATION

• A. History

• g. Awakening time

• h. How do you feel upon awakening?

• i. Naps

• j. Sleepiness

• k. Weight gain/edema

• l. Sleeping aids (alcohol)

IV. INVESTIGATION

• A. History

– 2. Past Medical History (PMH)

• a. Tonsillectomy/adenoidectomy

• b. Nasal surgery/fracture

• c. Hypertension

IV. INVESTIGATION

• A. History

• f. Cardiac/cerebrovascular disease

• g. Diabetes/hypothyroidism/acromegaly

• h. Pain: arthritis, fibromyalgia, headaches

• I. Lung disease

• j. Dementia

IV. INVESTIGATION

• A. History

– 3. Family history

IV. INVESTIGATION

• B. Physical examination

– 1. General appearance

– 2. Blood pressure, heart rate

– 3. Mental status examination

– 4. Obesity

IV. INVESTIGATION

• B. Physical examination

– 5. Airways

– 6. Heart failure

– 7. Stroke

– 8. Pain

IV. INVESTIGATION

• C. Sleep Diary

IV. INVESTIGATION

• D. Operational definitions of Sleepiness

– 1. Social/occupational impairment

• a. Mild; activities requiring little attention

• b. Moderate; activities requiring some attention

• c. Severe; activities requiring active attention

IV. INVESTIGATION

• E. Subjective measures of Sleepiness

– Epworth Sleepiness Scale

V. DIAGNOSIS

• I. Clinical (history and exam)

• II. Polysomnography

• III. Multiple Sleep Latency Test

V. DIAGNOSIS

• II. Polysomnography

– 1. Combination of EEG, EMG, EOG

– 2. Other physiologic parameters

• Oxygen saturation

• respiratory effort

• airflow

• EKG

V. DIAGNOSIS

• II. Polysomnography

– 3. Allows differentiation of 5-sleep stages (1968; Rechstaffen and Kales “A manual of standardized terminology, techniques and scoring system for sleep stages in human subjects”)

V. DIAGNOSIS

• II. Polysomnography (continued)

– non-rapid eye movement sleep (NREM) stages 1 through 4

– rapid eye movement sleep (REM)

– many sleep disorders associated with specific sleep stages

V. DIAGNOSIS

• B. Sleep Apnea: Obstructive sleep apnea-hypopnea syndrome (OSAHS)

V. DIAGNOSIS

• OSAHS

– 4-16% adults 30-60 years

– 24% independent adults > 65 years

– 33 % inpatients > 65 years

– 42% nursing home patients > 65 years

V. DIAGNOSIS

• OSAHS

– Polysomnography: Apneas and hypopneas

• apnea; complete obstruction

• hypopnea; partial obstruction

V. DIAGNOSIS

• OSAHS

• A/H duration; minimum 10 seconds

• absent/reduced airflow

• oxygen reduction

V. DIAGNOSIS

• OSAHS

• Severity

– 1. Apnea/hypopnea index (AHI)

– 2. Lowest oxygen saturation

– 3. Cardiac dysrhythmia

– 3. Sleepiness

V. DIAGNOSIS

• OSAHS severity

• 1. AHI

– mild; 5-15 events/hour

– moderate; 15-30 events/hour

– severe; > 30 events/hour

V. DIAGNOSIS

• OSAHS

• 2. SaO2 low

– > 90% = normal

– 80%-90% = mild

– 70%-80% = moderate

– < 70% = severe

V. DIAGNOSIS

• OSAHS severity

• 3. Cardiac dysrhythmia

– severe = any event inducing arrhythmia

V. DIAGNOSIS

• OSAHS severity

– 4. Sleepiness

• MSLT

V. DIAGNOSIS

• III. Multiple Sleep Latency Test (MSLT)

– Quantifies/qualifies sleepiness from micro/arousals

– Perform 1 1/2 to 3 hours after polysomnogram

– Five-20 minute nap attempts, separated by 2-hour intervals

V. DIAGNOSIS

• MSLT

– Sleepiness severity determined by mean sleep latency (average time to fall asleep for each nap)

• > 10 minutes = normal

• between 5-10 minutes = moderate

• < 5 minutes = severe

VI. THERAPY

• I. Therapeutic mainstays

• II. Supplemental interventions

• III. Others

– 1. Other surgeries

– 2. Appliances

– 3. Medications

VI. THERAPY

• I. Therapeutic mainstays

– 1. Continuous positive airway pressure therapy (CPAP)

VI. THERAPY

• I. Present therapeutic mainstays

– 2. Uvulopalatopharyngoplasty (UPPP)

VI. THERAPY

• II. Supplemental interventions

– Good diet

– Low-level exercise

– Avoid CNS depressants

– Good sleep hygiene

VI. THERAPY

• III. Other therapies

– 1. Other surgeries

• Tonsillectomy/Adenoidectomy

• Nasal reconstruction

• Maxillo-mandibular

• Cranial-facial advancement procedures

• Laser-assisted UPPP

• Somnoplasty

VI. THERAPY

• III. Other therapies

– 2. Appliances

• Generally not “curative”

• Reduce AHI < 20 if other therapy fails

• Mandibular positioning devices

• Tongue retaining devices

VI. THERAPY

• III. Other therapies

– 3. Medications

• Protriptyline (Vivactyl) increases airway muscle tone

• Provera (medroxyprogesterone)

• Diamox

• Theophylline

• Oxygen

V. DIAGNOSIS

• C. Restless Legs syndrome (RLS)

– associated with Periodic Limb Movement Disorder (PLMD) nocturnal myoclonus

– insomnia: disrupt sleep continuity

– sleepiness

V. DIAGNOSIS

• RLS/PLMD

– 5%/45% of independent patients > 65 years

– iron deficiency anemia

– kidney disease

– drugs/withdrawal

– neurologic disorders

V. DIAGNOSIS

• RLS/PLMD

– Polysomnography

• movement index; 5-25 = mild, 25-49 = moderate, 50 or more = severe

• movement-arousal index; 5-25 = significant, > 25 severe

• disrupted sleep = sleepiness (MSLT)

VI. THERAPY

• RLS/PLMD

– Treatment

• correct medical problems

• dopaminergics

• opiates

• benzodiazepines

VII. CONCLUSIONS

• Insomnia and excessive sleepiness is ubiquitous in the general population. The working public is at risk for a variety of specific sleep disorders, some which may relate to the work schedule.

VII. CONCLUSIONS

• In shift workers, determining physiologic suitability for the job, strict adherence to a consistent sleep/wake schedule, good sleep hygiene practices, bright light therapy, and possibly, in the future, the judicious use of medications such as melatonin, may optimize adaptation to night work.

VII. CONCLUSIONS

• In general, good dietary practices with low level exercise when possible, and the avoidance of unnecessary CNS depressants/stimulants can improve overall sleep, and simplify the diagnosis and treatment of a variety of other primary and secondary sleep disorders should they occur.

ADDITIONAL REFERENCES

• Dyken ME, Yamada T. Approach to the patient with sleep abnormalities. In: A practical guide to clinical neurology; Second Edition (ed) Biller, J. Boston, Little Brown and Co. 2002:99-118.

• Kryger MH, Roth T, Dement WC. Principles and Practice of Sleep Medicine (Third Edition). Philadelphia : Saunders, 2000.

• Hauri PJ. Consulting about insomnia: A method and some preliminary data. Sleep 16(4):344-350, 1993.

REFERENCES

• American Academy of Sleep Medicine Task Force. Sleep-related breathing disorders in Adults: recommendations for syndrome definition and measurement techniques in clinical research. Sleep 22:667-689, 1999.

• Dyken ME, Yamada T, Lin-Dyken DC . Polysomnographic assessment of spells in sleep; nocturnal seizures versus parasomnias. Seminars in Neurology. 21(4):377-390, 2001.

• Campbell SS, et al. Exposure to light in healthy elderly subjects and Alzheimer’s patients. Physiol and Behavior 42:141-144, 1988.

REFERENCES

• Webb WB, Agnew HW, Jr, Dreblow L. Sleep of older subjects on shift work. In Reinberg A, Vieux N, Andlauer P (eds): Night and Shift Work: Biological and Social Aspects. Oxford , Pergamon Press, 197-203, 1981.