Importance of SleepLisa Medalie, PsyD, RPSGT, CBSM

Behavioral Sleep Medicine SpecialistThe University of Chicago

Sleep Medicine

Sleep Introduction

How sleep is defined and measured

What is Sleep?Definition:-A complex reversible state characterized by diminished responsiveness to external stimuli and a stereotypical species-specific posture. -Sleep is generated and maintained by central nervous system (CNS) networks that use specific neurotransmitters located in specific areas of the brain.

Characteristics:-Active and highly regulated process -Composed of two fundamentally different states: REM sleep & NREM sleep

PurposeNot understood

Hypotheses: Restoration and recovery of body systems; immune system support; learning and memory consolidation; protection from predators; brain development; discharge of emotions

Kryger, Roth, Dement (2005); National Institute of Health, National Center on Sleep Disorders Research (2003)

How do we study sleep?

Kryger, Roth, Dement (2005); National Institute of Health, National Center on Sleep Disorders Research (2003)

EEG CharacterizationWake: alpha, frequency 9-12 hz

Stage 1: smaller amplitude and irregular frequency, theta waves with vertex spikes

Stage 2: Stage N2 sleep is defined by the presence of either K complexes or sleep spindles

Stage 3: large amplitude, very slow waves, delta waves

REM: low-amplitude mixed-frequency EEG activity,

Kryger, Roth, Dement (2005); National Institute of Health, National Center on Sleep Disorders Research (2003)

Sleep Stage Distribution

Proportion of sleep stages in normal sleep: REM:25% NREM: 75%Stage 1: 5%Stage 2: 45%- 50%Stage 3: 20%- 25%

Stage 1

Stage 2

Stage 3Stage 2

REM Sleep

90-120 min

Kryger, Roth, Dement (2005); National Institute of Health, National Center on Sleep Disorders Research (2003)

Non-REM vs. REM SleepNREM REM

Synchronized EEG activity Paradoxical sleep since EEG resembles a waking pattern

Slow or no eye movements and tonically active EMG

Muscles are atonic except the diaphragm and extraocular muscles

Intact thermoregulatory response to changes in ambient temperature

Absent thermoregulatory response to ambient temperature

Regular respiratory pattern Irregular breathing pattern with variable RR

Heart rate and BP are lower than relaxed wakefulness

HR and BP are similar to relaxed wakefulness

Unfocused thought with occasional short dream

Abundant long dreaming with clear recollection of its content

Kryger, Roth, Dement (2005); National Institute of Health, National Center on Sleep Disorders Research (2003)

Physiology of Sleep:The Two-Process Model

Sleep homeostasis (Process S) :-A process that keeps track of how much time has passed awake (or asleep)-SWS increases when sleep pressure is high and decreases when sleep pressure is low. -Adenosine (neurotransmitter) regulates homeostatic sleep drive.

Circadian rhythm (Process C):-A clock that keeps time irrespective of what happens in the environmentPeaks in alertness = late morning and early eveningTroughs in alertness= early morning and early midafternoon

Borbély (1982); Daan et al. (1984); Borbély & Achermann (2005)

Sleep Patterns and Age

Average total sleep time REM percentage

Common Sleep Disorders• 12 million Americans• Interrupted breathing during sleep• Drops in oxygen and partial arousals• Excessive daytime sleepiness

Obstructive Sleep Apnea

• Neurologic movement disorder• Unpleasant leg sensations – urge to move legs• Worse at rest• Associated with Periodic Limb Movement Disorder

Restless Leg Syndrome

• 250,000 affected, fewer than half diagnosed• Excessive and overwhelming sleepiness – sleep attacks• Cataplexy, Sleep Paralysis, Hypnogogic/Hypnopompic HallucinationsNarcolepsy

Insomnia• One third symptoms, 6-10% diagnosis• Difficulty falling and or staying asleep• Impaired daytime functioning and /or distress

Sleep and Cognition in Adults

Effects of Sleep Deprivation and Sleep Disorders

Sleep Deprivation and Cognition

A: Correct scores on CPTB: Error scores on CPT

Level: Increases with difficultySD: 24 h sleep deprivation

Joo et al. (2012). J Clin Neurol; 8(2): 146-150

Insomnia and Cognition

Studied 20 patients with Primary Insomnia (mean age, 50 yrs; 18 females) and 20 Age-, gender-, and education matched Good Sleepers

Noh et al. (2012). J Clin Neurol

Sleep Apnea and Cognition

Canessa et al. (2011). Amer J of Resp and Crit Care Med

Sleep and Cognition in Children

Sleep and Attention Deficit Hyperactivity Disorder (ADHD):

A Causal Conundrum

Hyperarousal Theory• Hyperactivity in children with ADHD is caused by

overstimulation of the central nervous system• The state of physiological arousal in children with ADHD is

drastically elevated• Hyperactive behavior in children with ADHD is related to a

deficiency in effectively censoring information signaled from the environment

• Too much information comes in, and individuals are unable to modulate the impact of overflowing stimulation which presents as hyperactivity

(Busby, Firestone & Pivik, 1982; Hastings & Barkley, 1978)

Hypoarousal Theory• A low level, not high level, of central nervous system arousal

causes difficulty inhibiting sensory input and behaviors• Excessive, unproductive behavior is caused by inhibited

control of sensory input• Hyperactivity in children with ADHD is a compensatory

mechanism for a system which processes external stimulation too slowly

• When individuals are processing too slowly to function in their environment, the system overcompensates to speed up the system with fast production of behavior

(Satterfield, 1975)

Relevance to Sleep

• Hyperarousal Theorists: Individuals with ADHD have difficulty settling because of their hyperaroused central nervous system activity. Difficulty settling makes for difficulty sleeping

• Hypoarousal Theorists: Sleep disturbance leads to excessive sleepiness which slows processing. Hyperactivity is a compensatory behavior to keep children awake in the face of sleep deprivation

Sleep and Cognitive Functioning

• PSG on 82 healthy children randomized to sleep deprivation or optimal sleep

• Found patients in sleep deprived group exhibited increased symptoms of ADHD the following day

(Fallone et al. 2001)

Sleep Disorders and ADHDDisorder Findings

Insomnia Increased bedtime resistance, increased sleep-onset difficulties, increased instability of sleep onset, difficulties settling down, interruptions during bedtime routines and anxiety (Corkum et al., 2001; Owens et al. 2000; Cortese et al., 2009; Hvolby et al. 2009; Corkum et al. 1999)

RLS RLS has incidence of 0.5% in general public (Picchietti et al., 2007). Approximately 44% of children with ADHD have been found to have restless legs syndrome (RLS) or RLS symptoms, and up to 26% of subjects with RLS have been found to have ADHD or ADHD symptoms (Cortese et al. 2005)

OSA In healthy 3-5 year olds apnea–hypopnea index is 0.90 ± 0.78 (range: 0–3.6) and in 6–7-year-olds is 0.68 ± 0.75 (range: 0–6.6), while a range of 0–1.7 has been reported in children with attention-deficit/hyperactivity disorder of comparable age ranges (Goraya et al, 2009)

(Spruyt & Gozal, 2011)

Study of Sleep Habits and Stimulant Usage in College Students

• Participants: 19 college students (18-22 years old) diagnosed with ADHD and receiving accommodations through Academic Support

• Instrumentation: Participants completed a 3 week, medication form and daily medication/academic functioning/sleep habits log– Self report – 0-5 likert scale items (0 = poor, 5 = excellent)

Variable Non Med Med

M M T (17) P

Sleep Onset Latency (Min)

27.50 70.22 2.0 .03

Sleep Onset Latency in Medicated vs. Non-Medicated College Students with ADHD

-Sleep onset latency difference between medicated and non-medicated groups reached significance. There was a non-reported trend towards significance for medicated students to sleep approximately 60 minutes less than their non-medicated counterparts.- Average total sleep time in medicated group was 6 hours and non-medicated group was 7 hours

• 50% of medicated students in this study increased their prescribed stimulant dose

Review of ADHD-Sleep Relationship

• 1. Sleep problems may mimic ADHD symptomatology• 2. Sleep problems may exacerbate underlying ADHD symptoms • 3. Sleep problems may be associated with or exacerbated by ADHD• 4. Psychotropic medications used to treat ADHD may result in sleep problems.

• In any individual, the relationship between ADHD treatment and sleep may be:– 1. Direct effect (i.e., improve, worsen sleep) – 2. Indirect effect (i.e., ADHD medications or treatment improve comorbid condition or

functioning, and sleep subsequently improves) – 3. May be a moderator of response (e.g., sleep problems may limit dosing necessary to achieve

an optimal response

(Owens, 2005; Stein, Weiss & Hlavaty, 2012)

Parent/school report of ADHD symptoms

Screen: BEARS, Clinical Interview

RLS OSA Insomnia

If (+) Sleep Disorder If (-) Sleep Disorder

Sleep Study Sleep Logs, Actigraphy

Consider ADHD Treatment Options: If use of medication (particular stimulant)

educate on sleep hygiene and consider dose timing issues

Treat Sleep Disorder then re-evaluate ADHD symptoms

Summary

• We are still unsure exactly why we sleep• How we sleep is best explained by shift in EEG activity

and by taking into account sleep homeostasis and circadian rhythmicity.

• The importance of sleep is at least somewhat confirmed by negative cognitive consequences of insufficient sleep.

• Screening of sleep disorders in patients with ADHD seems warranted

• Treatment for sleep disorders are available. Patients with complaints of sleeplessness or sleepiness have options.

Sleep Complaints

Behavioral Sleep Medicine

Sleep Medicine

Sleep ApneaPeriodic Limb Movement DisorderNarcolepsyIdiopathic Hypersomnia

Actigraphy Sleep LogsCognitive Behavioral Treatment for Insomnia

Overnight Sleep StudyDaytime Nap StudyCPAPMedication Management

InsomniaCircadian Rhythm DisordersInadequate Sleep HygieneNightmare DisorderNight Eating Syndrome