Week 3: Sleep
Mindfulness
Importance
33% of adults experience
sleep difficulties
Sleep Changes
in older adults
Sleep Architecture
Shorter REM
⬇ dramatically throughout childhood
⬇ steadily during adulthood
Stabilises after age 60
⬆ percentage in infants
Shorter SWS
Young adults
Older adults
⬇ amplitude and density of SWS with maximal reduction in frontal lobe
Changes in homeostatic drive regulation
Smaller decrease in SWS throughout night with sleep
Smaller increase in SWS with prolonged wakefulness
Sleep spindles
transient bursts of waxing and waning oscillations in the 11Hz to 16Hz
commonly found in NREM Stage 2 but also in SWS
Older adults 👴
Significant ⬇ in spindle density with largest reductions in frontal regions
⬇ spindle activity associated with impairments in hippocampal memory
Sleep Parameters
Sleep Duration
plateaus after 60
10 to 14 hours in children
6.5 to 8.5 hours in 20 to 35 yr olds
5 to 7 hours in
35 to 60 yr olds
Daytime ☀
napping
Statistics
⬇ in sleep duration offset by ⬆ in daytime napping
50% of unplanned naps in older people
Reported by 10% of 55-64 yr olds and 25% of 75-84 yr olds
25% of older people experience EDS that regularly impairs daytime activity
Circadian Rhythms
📉 in amplitude of bodily circadian rhythms (hormonal cycles, melatonin secretion, body temp)
⬆ vulnerability to factors disrupting circadian rhythms
Timezone changes
advancement in circadian cycles
earlier sleep and wake times
Clock Genes
⬆ deterioration in clock gene expression in peripheral tissues
⬇ ability of the suprachiasmatic nucleus (SCN) to entrain and regulate peripheral clocks
Insomnia
Criteria
Exclusion
1⃣ More than one symptom
3⃣ Occurs at least 3 nights per week for at least 3 months
occurs despite adequate opportunities for sleep
Short-term ➡ less than 3 months
Chronic ➡ more than 3 months
4⃣ Not caused by other disorders or substances
2⃣ More than one associated daytime symptom
Treatment
Pharmacological
Psychological
intended for short-term use (1-2 weeks)
80% success rate post-treatment
multifaceted treatment approach required
CBT-I
cognitive and behavioural treatments
Cognitive Therapy
Sleep restrictions
Cognitive Decline
Sleep duration changes in middle-aged
Risk Factors
Substances
Sleep Medications
Hyperarousal
Hypothesis
24hr psychobiological disorder because etiology related to
neurobiological substrate alterations
maladaptive behaviours and cognitions
evidence supports hypothesis for younger adults but not older adults
late-life insomnia characterised by commorbid insomnia
competing factors with hyperarousal in insomnia experience
Polypharmacy
use of multiple medications (5 or more)
⬆ likely to take multiple medicines for commorbities
many medicines affect sleep and wake
Psychotropic drugs
affects neurotransmitter systems involved in sleep-wake cycle
drug that affects persons mental state
antidepressants
unintended insomnia or sedation
⬆ limb/eye movements that disrupt sleep
REM sleep supression
Examples
FDA approved hypnotics
Off-label agents
sedating antidepressants:
trazodone, mirtazapine
sedating antipsychotics: quetiapine
benzodiazepine receptor agonists: zolpidem and eszopiclone
5 times the odds ratio of medicine prescription for sleep in adults over 65 compared to 18-35 year olds
Hypnotic Risks
Stats
age-related changes in drug metabolism and clearance
Tolerance development
👴🏼 have nearly 5x ⬆ risk of unwanted cognitive and psychomotor effects from hypnotics relative to placebo
RIsk of cognitive impairment
antidepressants, anxiolytic medications, sedative hypnotics most common potentially inappropriate medications in community-dwelling elderly patients
Dementia
Anticholinergic meds
1st-gen antihistamines
antagonism of H1 receptors
has anticholinergic effects
dementia risks ⬆in heavy past users and recent users
risk may persist despite discontinuation.
often used to manage poor sleep and depression (prodromal phase)
suggests indirect association of anticholinergic meds and dementia
⬆ risk for nonhypnotic and nonantidepressant anticholinergic meds
⬇ likelihood that dementia risk related to only sleep problems
showed 10-yr cumulative dose response rs with dementia dev
Zolpidem
⬆ risk for short-term cognitive effects
conflicting results linking it to dementia
Neurocognitive Disorders
wide array of progressive illnesses
tauopathies (AD)
synucleinopathies (PD)
Dementia and sleep problems
Sleep disturbances comprise earliest preclinical symptoms of dementia
Problems initiating
and maintaining sleep
poor sleep quality
EDS
may begin decades before dementia onset
onset & progression of sleep problems may occur with preclinical histopathological dev of dementia before cognitive symptoms
Research
Findings
sleep problems may not only occur as a result of dementia but also contribute to it
Dementia Patients
treating sleep problems linked with improvement in above problems
⬇ sleep associated with ⬇ cognitive function, behavioral & psychological symptoms
Treatment of Sleep Problems in Middle Age
Benefits
Challenges
⬆ evidence that pathologic sleep changes in middle age => abnormal acceleration of cog. decline
most apparent in the concurrent development of sleep disturbances, cognitive changes, and histopathological changes in dementia patients
important to diagnose & treat sleep problems particularly in middle-aged population
may slow or arrest pathologic cognitive changes in later life.
Examples
melatonin
sedating antidepressants
mainly prescribed hypnotics (sleeping pills)
Side Effects
impaired cognitive functioning
⬆ risk of falls (salient)
parasomnia-like symptoms like sleep walking & sleep eating (salient)
daytime sleepiness
Even for newer BRA drugs designed to ⬇ negative side effects
after that => ⬆ potential for tolerance or dependance
benzodiazepine receptor agents
effective with no withdrawal effects or rebound insomnia
small treatment effects
zalepon effective for 3-6 mth usage
unfavourable benefit-risk ratio for 👴🏼
small to moderate magnitude of improvements
Relaxation therapy
matching time spent in bed
to actual sleeping time
Stimulus control
Sleep Hygiene
Benefits
regarded by national agencies as firstline treatment for chronic insomnia before pharmacological
substantial efficacy for primary/comorbid insomnia with moderate-large effect sizes
Older adults with insomnia => significant improvement in insomnia symptoms
⬆ wake time associated with cognitive complaints as early as 2 years and as late as 28 years
Longitudinal
self-reported insomnia associated with ⬆ cognitive decline
Nurse Health Study &
Honolulu Aging study
no associations between insomnia and cognitive performance
Meta-analysis (5 studies)
1.5-fold risk of dementia dev in 👴🏼 with insomnia
did not analyze all insomnia subcomponents or objective measures of sleep quality/quantity
Studies on extreme sleep durations
impairments in executive function, working memory, attention, episodic memory, cognitive complaints
both long and short sleep duration
long sleep duration (≥ 10hrs) linked to ⬇ cognitive performance in 👴🏼
also correlated with other medical conditions and overall poor health
Sleep duration changes of ≥ 2 hours in middle-aged adults linked with ⬇ cognitive performance
⬇ associations in 👴🏼 controlling for demographics & health related variables
Development
Predisposing
Precipitating
Perpetuating
stressful life events (retirement, bereavement)
⬆ time spent in bed
excessive napping
loss of daytime structure
Prevalence
Studies in 5 countries
ranges from 9% to 44%
higher estimates when diagnosed without considering daytime impairments or insomnia duration & frequency
SG
⬆ frequency in 🚺 and gap widens in older adulthood
13.7% of adults report ≥ 1 sleep problem
69.4% ➡ sleep interruptions at night
48.9% ➡ difficulties falling asleep
22.3% ➡ early morning awakening
11.4% ➡ all 3 problems
Impaired plasticity
Family history
Hyperarousal
Personality factors
vary in content, duration, quality
short-term behaviors/cognitions that seem to be logical solutions to ⬇ sleep disruption
may create ⬆ sleep pattern variability, non-sleep-promoting environment, unrealistic expectations of sleep in long-term
stimulating substances to help wakefulness
sedative substances to fall asleep
event that introduces transient sleep disruption
psychosocial stress
SES
Poverty & ⬇ educational attainment related to ⬆ sleep disturbance & insomnia complaints
may relate to insomnia through
⬇ social support
food insecurity
unhealthy lifestyle
Hypnotic Dependence
insomnia symptoms & complaints despite chronic use of hypnotic meds for treatment
👴🏼 seeking insomnia treatment likely to receive hypnotic medications as first-line treatment
⬆ risk of developing hypnotic-dependent insomnia
related to maintenance of chronic insomnia.
withdrawal attempts from hypnotic
insomnia temporarily worsens
incentivizes continued use of hypnotics in 👴🏼 despite ⬇ efficacy
Increased to 88% in
adults over 65
👴🏼 with poor or inadequate sleep
⬆ risk for ⬆ cognitive, mood & functional impairments
⬇ self-rated health
depression symptoms
⬆ number of physical disabilities
respiratory symptoms
use of prescription medications to induce sleep or reduce anxiety
Chronic sleep complaints & excessive
daytime sleepiness (EDS) in 👴🏼
associated with problems of
psychomotor retardation
mood disorders and dementia
memory and attention difficulties
problems may worsen other health conditions
⬆ economic burden & ⬇ overall quality of life
stress for family and caregivers
⬆ risk of injury from falls & unsafe driving
structural organisation of sleep
nREM (1, 2, 3) => REM
SWS activity highest in 1st NREM cycle
⬇ with subsequent sleep cycles
bound to homeostatic drive regulation
⬆ activity in response to time spent awake
last 0.5 to 2 seconds
role in various learning paradigms
consolidating memory of word-pair associations
procedural memory tasks
⬇ amplitude & duration of sleep spindles
Reasons
longer sleep onset latency
⬆ wake time after sleep onset (WASO)
⬆ sleep fragmentation
early morning awakening
EDS may be related to ⬆ sleep fragmentation
related to comorbid conditions (sleep disorders, medical disorders & depression)
Vision loss
Reduction of daytime
General patterns
sleep of healthy older adults compared to younger adults
Lighter
⬇ deep sleep (stage N3) & ⬆ light sleep (stages N1 & N2)
More disrupted
⬆ difficulty falling back asleep
⬆ awakenings
longer time to fall asleep
sleep architecture shifts occur before 60 then plateau
continues till late older adulthood (≥90)
Unclear reasons
Biopsychosocial
Age-related changes in multiple neurobiological substrates (eg. cortisol, serotonin, growth hormone)
2 Ingredients
Single-minded focus
Distracted attitude
Barriers BA2D4
Discomfort (physical)
Drowsiness
Depression
Doubt
Anger
Anxiety
Boredom