To Sleep or Not to Sleep…

May 6 2010 D. Nesdoly MD FRCPC

To Sleep or Not to Sleep…

Consequences of Sleep Loss

Scenarios

Scenarios01230123

0004

2400

04000149

0200

0645

Objectives

Sleep Science historySleep Mechanics 101Sleep Deprivation ConsequencesShift-work risks ‘evidence’

Strategies Future research

Sleep Science History

1930 Berger- “Father of EEG”1937 Loomis- first overnight EEG human sleep recordings

1968 Standardized manual1974-Williams normative sleep data

2010-Accreditated Sleep Centers

Sleep Basics 3

Mechanisms ANS

PNS SNS

Homeostatic Sleep Drive

Circadian Sleep Rhythm

Sleep Stages

Sleep Stages

Sleep Stages

Sleep Waves

Sleep Architecture

Sleep Architecture

Sleep Architecture

ircaCircadian Sleep

Disorders

Sleep Quantification

ObjectiveMSLTMWTPVT

SubjectiveSleepiness scales

Stanford (1973 7 point)

Karolinska (1990 9 point)

Epworth (1991 situation-specific dozing likelihoods)

Effects of Sleep Deprivation

Effects of Sleep Deprivation

Effects of Sleep Deprivation

Recovery Studies

Recovery Studies

Recovery Studies

Recovery Studies

Shift-work Syndrome

Prevalence(U.S.-22 M SW +3% )Canada 11% rotating, 6% evening, 2% nights

Prototype Insomnia / Sleepiness Fatigue / Headache / Anxiety Indigestion / Pyrosis Hypertension Weight gain Menstrual irregularity / Sub-fertility / SA Depression Drowsy driving

Sleep Deprivation Impact

IndividualFamilyCommunitySociety

Shift-work Impact

Shift-work Impact

Shift work + Cardiovascular Disease

Modest (+) associations w shift work (40%)

Causal link research inconsistent Daylight Saving Time *

Janszky (2008) Acute MI risk Mondays“Spring” Incidence ratio 1.051“Autumn” Incidence ratio 0.985

Shift work (LAN) + Cancer

Schernhammer (2001) Nurses Health Study Cohort240,000 women over 30 yearsControl for major risk factors, stress, SE statusCancer relative risk

Breast 36-79 %Colon 35%Endometrial 43%

2007 IARC classifies ‘night shift work’ as probable carcinogen (2A)

Shift work (LAN) + Cancer

Observational studies: modest (+) relationship b/w LAN + breast Ca

Pukkala (1995) Flight attendants > 15 YTynes (1996) Radio + telegraph operators

Prostate Ca Airline pilotsFirefightersHealth practitioners + physicians

Circadian Disruption Shift

work + Risk of CaSeattle Research group

LAN + Breast Ca Case control study60-Hz magnetic fields + nocturnal melatonin

Night shift work + biomarkersMelatonin + hormonesGenotypes (hCLOCK, Per2, Per3)

Shift work + Pregnancy

Moderate (-) effect on fetal growthSGA / LBW

No association for pre-term delivery or pre-eclampsia

Study Limitations

Epidemiologic vs RCTSelection bias

“Survivor population” (entrance + drop-out)

Lower socioeconomic statusShift work definitionExposure measurement

Shift Work Proposed Mechanisms

Shift-work + Risk

Needle-stick eventsAyas (2006) Trinkoff (2007)

Clinical performanceHoward (2003)-AnesthesiaLockley (2004)-ICUSmith-Coggins (2006)-Emergency

Transportation Safety

Prototype ‘drowsy driver’Young male < 25Shift-workerUntreated sleep disorder (OSA / Narcolepsy)

Event 2400-0700Social Media: “Contagious”

Transport + Sleep Deprivation

CommercialTruckRailAir / ATC

Performance impairment = Ethanol intoxicationDawson 1997Powell 2001Vakulin 2007

Drowsy Driving Strategies

AwarenessLegislationHighway rumble stripsOperator behavior

NapsCaffeineEnvironmental stimuli

Sleep Loss Countermeasures

PharmacologicNon-pharmacologic

Sleep Loss CountermeasuresPharmacologic

AntihistaminesBenzodiazepinesNon-benzodiazepinesAntidepressants

Serotonin modulator SSRIS SNRI Tetracyclic Tricyclic

Melatonin receptor agonistAlternative

Valerian Kava Chamomile Synthetic melatonin

Non-pharmacologic

Sleep Loss Countermeasures

PharmacologicNon-pharmacologic

BehaviouralSleep deprivationReconditioningRelaxation techniquesCBT

Schedule strategiesRestrict maximum 3 consecutive shifts

Forward shift rotationParticipatory approach

Wolkove, N. et al. CMAJ 2007;176:1449-1454

Sleep Hygiene

Wolkove, N. et al. CMAJ 2007;176:1449-1454

Sleep Hygiene

Wolkove, N. et al. CMAJ 2007;176:1449-1454

Sleep Hygiene

Wolkove, N. et al. CMAJ 2007;176:1449-1454

Sleep Hygiene

Wolkove, N. et al. CMAJ 2007;176:1449-1454

Sleep Hygiene

Future Research

Common definitions (SW)Common assessment (exposures)

Study intermediate pathways vs disease outcomes

Outcome data NOT biomarkers

Summary

Sleep science ‘101’Sleep debt awarenessSleep hygiene / ‘art’ of sleeping

Drowsy driving KILLS people

Reference List

Any Questions?Erica

A baby friendly way to establish