Top Banner
ABC of Sleep Disorders DAYTIME SLEEPINESS J D Parkes "Dream of the Home Country" by Shoko Kawasaki. Patients' descriptions of tiredness and fatigue compar4 "Physical" tiredness "Mental" tiredness Sleepi Tired Poor concentration Feel sl Fatigued Poor memory Look s Exhausted Little interest Can't. Weak Irritable Sleep Muscle aching Jaded Alway No energy Sad Alway Lie down to recover Cannot get out of bed Do no .-- -I I _ ._,<_ 7 /-/ ^ r. "Damn the boy, he's fallen asleep again." (Dickens.) Daytime sleepiness (hypersomnia) is a common and serious complaint, although it is less common than insomnia. In a recent community survey in the United States (in Newhaven, Baltimore, St Louis, Durham, and Los Angeles) 102% of the sample at the time of the interview described insomnia, and 3-2% described hypersomnia. Those most affected were young and unemployed people. The complaint of excessive daytime sleepiness includes inappropriate and undesirable sleep during waking hours; reduced motor and cognitive performance; unavoidable napping; sometimes-but not always-an increase in total 24 hour sleep time; and occasionally states of incomplete arousal with automatic behaviour and sleep drunkenness, slufted speech, impaired motor control, and difficulty in focusing. The disability caused by severe daytime sleepiness is comparable with that of severe epilepsy. Many hypersomniac patients are labelled dull, lazy, workshy, or stupid, and if they need treatment are considered to be drug addicts. They have considerable problems at school, work, and home. Daytime sleepiness is an important cause of industrial and road traffic accidents. Gaps of several years between the start of symptoms and the achievement of a definite diagnosis of the cause of the sleepiness are common. Excessive daytime sleepiness can be divided into two patterns: persistent-for example, ed with sleepiness narcolepsy and symptomatic sleep apnoea, and iness intermittent-for example menstrual hypersomnolence and the Kleine-Levin leepy syndrome (both rare). This article focuses on the 3leepy more common disorders. stay awake When not secondary to persistent insomnia, 's half awake daytime sleepiness usually has an organic rather 's dozing than a psychological cause, though it may be an I have to go to bed to sleep early (or the only) complaint in depression. Diagnosis usually depends more on history than on physical signs. In many cases the cause of daytime sleepiness can be elicited from a careful history supplemented by watching the patient sleep. Important diagnostic features include episodes of sleep (rather than just sleepiness during the day); the inability to stay awake; and the propensity to go to sleep anywhere, not just in bed. Most subjects with excessive daytime sleepiness go to sleep readily at night (within seconds of going to bed), although their sleep may then be interrupted. Fatigue, exhaustion, and tiredness are not the same as excessive daytime sleepiness and have different causes, and a difficulty in diagnosis is the fact that many illnesses and many drugs may cause both fatigue and sleepiness. It is important to distinguish between daytime sleep attacks and other causes of altered awareness such as epilepsy, hypoglycaemia, orthostatic hypotension, cardiac disease, and various psychological problems. The distinction is usually obvious but, in particular, it can be difficult to differentiate between atonic seizures and cataplectic attacks. BMJ VOLuM 306 20 MARCH 1993 History 772 on 28 October 2020 by guest. Protected by copyright. http://www.bmj.com/ BMJ: first published as 10.1136/bmj.306.6880.772 on 20 March 1993. Downloaded from
4

ABC of Sleep Disorders DAYTIME - BMJ · Thenarcolepticsyndrome Thenarcolepticsyndromeis characterisedbyexcessivesleepandsleep episodes, andcataplexywithorwithoutsleepparalysis,hypnagogic

Aug 07, 2020

Download

Documents

dariahiddleston
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: ABC of Sleep Disorders DAYTIME - BMJ · Thenarcolepticsyndrome Thenarcolepticsyndromeis characterisedbyexcessivesleepandsleep episodes, andcataplexywithorwithoutsleepparalysis,hypnagogic

ABC of Sleep Disorders

DAYTIME SLEEPINESS

J D Parkes

"Dream of the Home Country" by ShokoKawasaki.

Patients' descriptions of tiredness and fatigue compar4

"Physical" tiredness "Mental" tiredness Sleepi

Tired Poor concentration Feel slFatigued Poor memory Look sExhausted Little interest Can't.Weak Irritable SleepMuscle aching Jaded AlwayNo energy Sad AlwayLie down to recover Cannot get out of bed Do no

.-- -I I

_ ._,<_7 /-/ ^

r.

"Damn the boy, he's fallen asleep again."(Dickens.)

Daytime sleepiness (hypersomnia) is a common and serious complaint,although it is less common than insomnia. In a recent community survey inthe United States (in Newhaven, Baltimore, St Louis, Durham, and LosAngeles) 102% ofthe sample at the time ofthe interview describedinsomnia, and 3-2% described hypersomnia. Those most affected wereyoung and unemployed people.The complaint of excessive daytime sleepiness includes inappropriate

and undesirable sleep during waking hours; reduced motor and cognitiveperformance; unavoidable napping; sometimes-but not always-anincrease in total 24 hour sleep time; and occasionally states ofincompletearousal with automatic behaviour and sleep drunkenness, slufted speech,impaired motor control, and difficulty in focusing. The disability caused bysevere daytime sleepiness is comparable with that of severe epilepsy. Manyhypersomniac patients are labelled dull, lazy, workshy, or stupid, and ifthey need treatment are considered to be drug addicts. They haveconsiderable problems at school, work, and home. Daytime sleepiness is animportant cause ofindustrial and road traffic accidents. Gaps of severalyears between the start ofsymptoms and the achievement of a definitediagnosis ofthe cause ofthe sleepiness are common.

Excessive daytime sleepiness can be dividedinto two patterns: persistent-for example,ed with sleepiness narcolepsy and symptomatic sleep apnoea, and

iness intermittent-for example menstrualhypersomnolence and the Kleine-Levin

leepy syndrome (both rare). This article focuses on the3leepy more common disorders.stay awake When not secondary to persistent insomnia,

's half awake daytime sleepiness usually has an organic rather's dozing than a psychological cause, though it may be anI have to go to bed to sleep early (or the only) complaint in depression.

Diagnosis usually depends more on history thanon physical signs.

In many cases the cause ofdaytime sleepiness can be elicited from acareful history supplemented by watching the patient sleep. Importantdiagnostic features include episodes of sleep (rather than just sleepinessduring the day); the inability to stay awake; and the propensity to go to sleepanywhere, not just in bed. Most subjects with excessive daytime sleepinessgo to sleep readily at night (within seconds ofgoing to bed), although theirsleep may then be interrupted.

Fatigue, exhaustion, and tiredness are not the same as excessive daytimesleepiness and have different causes, and a difficulty in diagnosis is the factthat many illnesses and many drugs may cause both fatigue and sleepiness.

It is important to distinguish between daytime sleep attacks and othercauses of altered awareness such as epilepsy, hypoglycaemia, orthostatichypotension, cardiac disease, and various psychological problems. Thedistinction is usually obvious but, in particular, it can be difficult todifferentiate between atonic seizures and cataplectic attacks.

BMJ VOLuM 306 20 MARCH 1993

History

772

on 28 October 2020 by guest. P

rotected by copyright.http://w

ww

.bmj.com

/B

MJ: first published as 10.1136/bm

j.306.6880.772 on 20 March 1993. D

ownloaded from

Page 2: ABC of Sleep Disorders DAYTIME - BMJ · Thenarcolepticsyndrome Thenarcolepticsyndromeis characterisedbyexcessivesleepandsleep episodes, andcataplexywithorwithoutsleepparalysis,hypnagogic

Examination

.;eCKisWo p;wn-UWOgW In patients with the narcoleptic syndrome1 Geneal physical examination gives normal results. About

Pain,t,A dopo, work, an.:vi ; nt two thirds of subjects with symptomatic2 t~~~~~~~~~~~~~~~~~. :.............. .! ;2 d ......uie..oobstructive sleep apnoea have signs of a restricted

Some genetic disohieor~esuft inule*epspn se(1k.ramplo, upper airway with receding chin, short neck, and.:.,'.)t t .tb y .......Famiial rgentlt~ee~wk,ei1sorers iwlidenu4olpticobesity. Sometimes there are signs of acromegaly

sydrme s.w.^aleepwet10*lf-.f............ uiwngl.vlc .. or thyroid disease. A third of subjects withparplysis, fatal fan~iffati enn1~J~iIbpat1iic y mn c and otonic dystrophy complain ofextremefamll is6mna: w :^ dayime drowsiness, probably from sleep apnoea,

3 Nou eu; 4 and in other neuromuscular disorders:These k gckid|dettrevs l1l i,e~ParkM lb~edisease1 :-hei :~e#' (particularly those that affect the diaphragn,

disa~ and higharousal with a'wl,W such as acid maltase deficiency) there may be.4 Mobk

.;xoe~eq~a pnd acromegaly5ar:cai~ae sleep epnoea severe sleep apnoea. Autonomic failure in6~~~ ~n Xa ;p.n 5 ~~~~~~~~~~~~~ ~~~~multiple system atrophy may present withlncldeafenstualnacrolepsy an KeeLOvin ydroe obstructive sleep apnoea, and this is present in up

6 Drg related ito half of all children and adolescents with theManydrugs -Willi syndlrome.SYMPLtho lmimic amities,n oskrs ahynV tc

Investigation and diagnosisThe history is more important than sleep

laboratory investigations, but laboratory studiesare sometimes essential. There is no one simplephysiological measure of excessive daytimesleepiness, and for accurate assessment a batteryof tests including subjective rating scales (such asthe Epworth sleepiness scale), tests of sustainedattention, and tests ofmotor and cognitive

Common causes of persistent daytime sleepiness . ....performance are needed. This approach is* The narcoleptic syndrome-This includes cataplexy as well as necessary for research rather than clinicaldaytime sleepiness. Sleep paralysis, insomnia, and pre-sleep dreams appraisal. The best clinical laboratory measure ofare common excessive sleepiness is the multiple sleep latency* Symptomatic obstructive sleep apnoea-This includes snoring, test. The test measures the "latency" (in a 20apnoea, and restlessnessapnoea, andrestlessness ~~~~~minute window) to stage 1, stage 2, or rapid eye* Sleep related motor disorders-These include hypnic jerks at onset movemetR ) sle on five oasio atwof sleep, bruxism, and periodic leg jerks throughout sleep. Other movement (REM) sleep on five occasions at two

parasomnias rarely cause daytime sleepiness hourly intervals during the day under standard* Depression-20% of depressed subjects with a sleep disturbance conditions. For reliable results the duration ofhave hypersomnia, not insomnia sleep during the previous night must be known,* Postviral fatigue syndrome-Sleep, tiredness, and fatigue may be and the patient must abstain from drugs, alcohol,long term consequences of viral illnesses and coffee before the test. A "median latency" of* Head injury-Daytime sleepiness may persist for long periods after less than seven minutes on three or more tests isany head injury considered abnormal, but a few apparently* Metabolic, toxic, and drug induced hypersomnolence-The sleepiness normal subjects do fail the test.of left ventricular failure, severe anaemia, and hypoglycaemia may result normal subjects thefistpfrom reduced cerebral glucose oxidative metabolism. Alcohol, In normal subjects the first period ofREMbenzodiazepines, and other drugs may cause daytime sleepiness and a sleep during night sleep occurs about 90 minutesurinary drug screen may indicate the correct diagnosis after the onset of sleep. In most cases the finding* Essential hypersomnolence-Some patients have recurrent daytime ofREM sleep at onset of sleep during 24 hoursleepiness, long unrefreshing naps, no sleep attacks, prolonged night sleep/wake monitoring, night polysomnographysleep, difficulty in waking up in the morning but not cataplexy, sleep (electroencephalography, electromyography,paralysis, or sleep apnoea. Total 24 hour sleep time is prolonged and electro-oculography, oreurngthomltple* Elderlypatients-Daytime sleepiness is common among elderly sleep latency test supports the clinical diagnosispatients, and may indicate the development of circadian as well assleep/wake disorders in degenerative brain disease. Chronic insomnia of the narcoleptic syndrome. A single day sleepas a result of physical or psychiatric illness is an important cause of recording without REM sleep does not excludesecondary daytime sleepiness this diagnosis. In addition to or separate from the

test, night oximetry or polysomnography may benecessary to define and evaluate hypersomnia,particularly when this is the result of sleepapnoea.The three common causes of excessive daytime

sleepiness are obstructive sleep apnoea (which isdealt with in a separate article), the narcolepticsyndrome, and idiopathic hypersomnia.

BMJ VOLUME 306 20 MARCH 19937 773

on 28 October 2020 by guest. P

rotected by copyright.http://w

ww

.bmj.com

/B

MJ: first published as 10.1136/bm

j.306.6880.772 on 20 March 1993. D

ownloaded from

Page 3: ABC of Sleep Disorders DAYTIME - BMJ · Thenarcolepticsyndrome Thenarcolepticsyndromeis characterisedbyexcessivesleepandsleep episodes, andcataplexywithorwithoutsleepparalysis,hypnagogic

The narcoleptic syndromeThe narcoleptic syndrome is characterised by excessive sleep and sleep

episodes, and cataplexy with or without sleep paralysis, hypnagogichallucinations (pre-sleep dreams), and disturbed night sleep. Anunequivocal history of cataplexy is necessary for a definitive diagnosis.

Cataplexy (loss ofmuscle tone and paralysis ofvoluntary muscles) iscaused by a sudden increase in arousal after being startled, surprised,,orexcited, and it accompanies many sporting activities, emotion, and in

particular laughte.r*-"Irontrt with agoraphobiaand parlysis wiVh fright in which the~muscle tone

Ch.eIcU~~~~~~~toha'~~~~~K' ~is ing%_ped, in cataplexy tone in facial, ostu~1,and 11s0 es is d bl e

:~Bedtime...... physi clmscle atonia an"rii" rlysis ofa. w03etip. REM sleep although the subject is awake. There

4 etupte are small phasic movements during cataplexy,5Owl orIk-Whts tTi fwhich are similar to those ofREM sleep, with eye

B XArousaI~oiiz Wjerks and muscle twitches of the face and limbs,and are a useful diagnostic feature. Pre-sleep

wat 4~u~. dreams and sleep paralysis also result from REM~~Sieepret.~~~~~~~~lm~~~~~~ activity at the onset of sleep.

Sisep ofleSt (hV~IC)~ The usual age of onset of excessive sleepinessl 0kinckreSed mot.r~ctIvY&~ii~ |, I and cataplexy in the narcoleptic syndrome is late

kici? adolescence, with a range of 4-70 years. RoughlySIe*ptaIkin~~~~~~~~~~~~ 5%/ to IO%/ ofpatients have an affected first degree

(0sllee ~tna& ~ n ~relative (parent, sibling, or child). ThisSfeeaIV~~4~ns.tor ~~Wak1A~)? syndrome has the highest reported HLA

association, 980/ of subjects having HIAsyndrome)?~~DR2(1 5)/DQwl(6). Negative HLA DR2 typing

It $lsepr8ieted n e0s twi5 H to largely excludes a positive diagnosis, but only 1 intO~~~hY~~!~~dI8if~~~~~ 500 HIA DR2 positive subjects have the

fWs~r.try ~QImaIfr-apn~~tirSfrtry rre$erty, syndrome.

1| See# related crt. a Hypersomnolencere""m..reqev . .- Common hypersomnolence syndromes,Dreamtimin4slep onst dren Oeq6 IteP on.V sally with prolonged night sleep,

ac;ivity,fl V~liSPT ~4~PflV8tiOfl,OI unremarkable sleep architecture, non-REM'Teei In *vsiti nra4e sleep onset, and periodic daytime sleepiness

L supranucIearp without cataplexy or sleep apnoea, are listed inthe box giving the common causes ofpersistentdaytime sleepiness.

Sleep, movement, and daytime drowsinessA few movement disorders during sleep may be accompanied by daytime

sleepiness. These include hypnic jerks at the onset of sleep, bruxism, andhead banging, but these conditions do not usually result in subalertness

Periodic rhythmic leg jerking during while awake.sleep with contraction of the anterior Rhythmic leg jerking periodically during sleep with contraction ofthetibial muscle is common and usually anterior tibial muscle is a common and usually benign disorder thatbenign increases in incidence with age. The condition may be familial, and often is

associated with restlessness of the legs (akathisia) during the pre-sleepperiod. Many sleep disorders are accompanied by this type of leg movementwhich is sometimes associated with daytime drowsiness. The diagnosis isestablished by electromyographic sleep studies.

TreatmentSummary oftreatment strategiesWhen the diagnosis is established central nervous system stimulants may

be given, which improve the quality of life, but treatment may have to be* Patients with narcolepsy and other continued all the patient's life. Treatment depends on the availability of

hypersomnias are not lazy, bored, such drugs as dexamphetamine, methylphenidate, and mazindol (it is not a

incapable drug addicts licenced indication). Individually titrated drug selection, dose, and timingincapabledrug addicts are essential. The patient usually feels undertreated, but this avoids side* Treatment is just as necessary for effects and it is usually possible to compromise. The dose should not bethem as it is for patients with increased unless tolerance develops. Tolerance may be treated bydiabetes or epilepsy withdrawal ofdrugs for 10-14 days, or by 3-6 month rotations of drugs.

Doses higher than dexamphetamine 60 mg/day, methylphenidate 100 mg/day, or mazindol 10 mg/day should be avoided and it should be possible tocontrol nacrolepsy with lower doses.

BMJ VOLUME 306 20 MARCH 1993774

on 28 October 2020 by guest. P

rotected by copyright.http://w

ww

.bmj.com

/B

MJ: first published as 10.1136/bm

j.306.6880.772 on 20 March 1993. D

ownloaded from

Page 4: ABC of Sleep Disorders DAYTIME - BMJ · Thenarcolepticsyndrome Thenarcolepticsyndromeis characterisedbyexcessivesleepandsleep episodes, andcataplexywithorwithoutsleepparalysis,hypnagogic

Ifmisuse ofdrugs is suspected, a plasma or urinary drug screen isindicated. Particular caution should be exercised when prescribing for'young and elderly patients, and for those with personality disorders andbipolar depressive illnesses.A simple sleep log with mood, alertness, and behavioural self rating scales

during the first three months of treatment helps to monitor treatment.Changes in lifestyle and behaviour will also help.For patients who wish to drive it is sensible to assess response over a six

month period before considering issuing a provisional licence.Central nervous system stimulants should not be prescribed to anybody

with a history of psychosis, physical violence, or drug misuse, or to woxnenwho are pregnant or breast feeding. Cardiovascular risks should be assessedwith care.

Sleep can kill. Professor J D Parkes is professor of clinical neurology, Kings College Hospital School of

Medicine and Dentistry, and Institute of Psychiatry, London.

The ABC of Sleep Disorders has been edited by Professor ColinM Shapiro.

Lesson ofthe Week

Acute bacterial meningitis in young adults mistaken for substanceabuse

LN Baldwin, A Henderson, P Thomas,M Wright

Bacterialmeningitis canpresent with acutedisturbance ofbehaviour whichmay closely mimicsubstance abuse

Intensive Care Unit,Princess AlexandraHospital, Woolloongabba,Brisbane 4102,Queensland, AustraliaLN Baldwin, senior registrarA Henderson, associateprofessorM Wright, director

Department ofEmergencyMedicine, PrincessAlexandra Hospital,Brisbane 4102P Thomas, consultant

Correspondence to:Dr Henderson.

BMJ 1993;30:775-6

Patients admitted to the casualty department withdisordered behaviour present a considerable diagnosticchallenge. An organic cause (acute confusional state orbrain syndrome) may be differentiated from an acutefunctional psychosis by the presence of abnormalneurological signs, particularly clouding of conscious-ness. Psychiatric symptoms, however, are poor diag-nostic discriminators.

In urban casualty departments an important cause ofacute brain syndrome occurring in adolescents andyoung adults is the abuse of therapeutic or recreationalsubstances, including alcohol.' In south east Queens-land the use of hallucinogenic leaves and petals of"angels' trumpets" (Brugmanasia sauveolens) is a par-ticularly common cause ofacutely disturbed behaviour.We present the case histories of two young adults

in whom acute behavioural disturbance, initiallydiagnosed and treated as substance abuse, was thepresenting manifestation of acute bacterial meningitis.

Case 1A previously well 15 year old, who had been living

with friends, became acutely violent and confusedshortly after his return home. Recreational drug abusewas suspected by his family and, with the help of thepolice, he was taken to the casualty department atthe Princess Alexandra Hospital. During the initialexamination he remained aggressive and confused.The axillary temperature was 37 3°C and he had atachycardia of 110 beats/min. Detailed neurologicalexamination was impossible but no focal abnormalitiesor neck rigidity were noted. To facilitate furtherinvestigations the patient was sedated and ventilated.As he was thought to have abused an hallucinogenicdrug, he was given activated charcoal and sorbitol bynasogastric tube. A white sell count of 30 1lx 109/l,a negative urine drug screen, and normal results oncranial computed tomography prompted examinationof the cerebrospinal fluid. Lumbar puncture, per-

formed three and a half hours after admission, showedturbid cerebrospinal fluid containing 1500 whitecells/,Jl (100% polymorphs), protein 5-7 g/l (normal0.15-0-45 g/l), and glucose 1 2 mmol/l. The Gram stainshowed intracellular diplococci, later confirmed asNeisseia meningitidis. He was given benzylpenicillinwith cefotaxime and transferred to the intensive careunit, where he subsequently made an uncomplicatedrecovery.

Case 2A previously healthy 34 year old man was arrested

after he was discovered defaecating in a neighbour'sliving room. He required physical restraint and wasthen taken to the local psychiatric hospital by thepolice. On examination the patient was extremelyagitated and appeared to be hallucinating. His axillarytemperature was 37°C, and his heart rate was90 beats/min. Further assessment was interruptedwhen the patient had a seizure. Acute self poisoningwas suspected, and he was transferred to the PrincessAlexandra Hospital. Following admission he remainedaggressive and required physical restraint. He was thensedated and ventilated to facilitate further examinationand investigation. Activated charcoal with sorbitol wasadministered by nasogastric tube. Subsequent investi-gations showed normal results on cranial computedtomography, with only alcohol present in the urinedrug screen. A full blood count, measured in bloodtaken on admission, however, showed a leucocytosis of36-9x 109/l (89%/ neutrophils). A lumbar puncture,performed five hours later, showed turbid cerebro-spinal fluid containing 2880 white cells/,ul (100%polymorphs), protein 6-4 g/l (normal 0.15-0.45 g/l),and glucose 5 1 mmol/I (blood glucose 8-8 mmol/l).Gram staining and culture gave negative results.Following penicillin and cefotaxime administrationhe was transferred to the intensive care unit, where hemade a complete recovery.

BMJ VOLUME 306 20 MARCH 1993 775

on 28 October 2020 by guest. P

rotected by copyright.http://w

ww

.bmj.com

/B

MJ: first published as 10.1136/bm

j.306.6880.772 on 20 March 1993. D

ownloaded from