Presentation about sleep

1. Ari Shechter, PhD
Assistant Professor of Medical Sciences
Columbia University Irving Medical Center
email: as4874@cumc.columbia.edu
twitter: @ShechterAri
Sleep Better, Live Healthier!
Public Health Conversation Series, UN
Division of Healthcare Management and
Occupational Safety and Health (DHMOSH)
June 9, 2021

2. Kryger, Sleep in Art

3. Kryger, Sleep in Art

4. 3 Pillars
of Health
sleep
exercise
nutrition

5. “Sleep is the intermediate state between wakefulness and death; wakefulness being
regarded as the active state of all the animal and intellectual functions, and death as
that of their total suspension”
Robert MacNish, member of the faculty of physicians and surgeons, Glasgow, in The Philosophy of Sleep, 1834
Sleep as passive;
inactive state of the
brain

6. Sleep is a dynamic and actively
produced brain state, with
accompanying changes to physiology.
Sleep is not static or passive!
We do not “turn off” during sleep
Some brain regions are more active during
sleep than wake (although some are lower)
Some hormones (growth hormone,
melatonin) are secreted selectively during
sleep (although some hormones and
systems are reduced)
Sleep
definition:
Neural and physiological

7. Sleep stages
and cycles
 Stage N1: Very light Sleep
o Transition from Wake to Sleep
o Drift in and out of sleep, awaken easily
o Hypnagogic jerk: Sense of falling followed by sudden
muscle contractions
 Stage N2: Relatively light but maintained sleep
o Brain activity relatively slower
o Breathing and heart rate slowed
o Maintained sleep
 Stage N3: Deep Sleep (Slow wave sleep)
o Lower brain activity
o High awakening threshold
o Restoration of body
 Stage REM: Rapid Eye Movement Sleep
o Very active brain activity
o Dreams
o Paralyzed body
Image: Psychology Today

8. Image: University of Minnesota Libraries (open.lib.umn.edu )

9. Sleep
quality

10. Circadian rhythm (circa= “about”, dian = “day”)
refers to body rhythms that have a roughly 24-
hour cycle.
Circadian
rhythms
Image: Nobelprize.org
The circadian clock anticipates and adapts our physiology to
the different phases of the day. Our biological clock helps to
regulate sleep patterns, feeding behavior, hormone release,
blood pressure, and body temperature.

11. Circadian
rhythms:
Melatonin
and cortisol
Melatonin: The “hormone of darkness”
Helps you fall and stay asleep
Cortisol: A “stress” hormone
Helps you wake up and start the day

12. Lack et al. Sleep Medicine Reviews, 2008
Circadian
rhythms:
Body
temperature,
Melatonin, and
Sleep

13. questions

14. Why do we spend up to one-third of our lives sleeping?
Cognitive
function
Mood
and
Emotion
Memory
Vigilance
and
Alertness
Obesity and
Diabetes
Cardio-
vascular
Immune
system
Cancer

15. WHO guidelines for sleep duration in children up to 1 year, 2-3 years, and 3-4 years old
• At least 7 hours of sleep per night is recommended to sustain health and safety in adults
• Too much sleep???
• Beyond duration:
• daily regularity of sleep duration and timing
• sleep quality (e.g., frequent awakenings during the night)
• daytime function: not feeling sleepy even after adequate sleep
• absence of sleep disorders (gasping for air/snoring; movement disorders, etc.)

16. Disorder Short sleep Insomnia SDB
Diabetes + + +
Hypertension + NA NA
CHD + NA X
Stroke + NA +
Total CVD X + +
+: statistically significant positive relationship
X: no statistically significant relationship
NA: no recently reported meta-analyses identified
Associations Between Sleep Duration and Disorders and
Incident CVD: Summary of Recent Meta-Analyses
Short sleep duration
• Increases the risk of diabetes by 30%
• Increases the risk of hypertension by 23%
• Increases the risk of CHD by 48%
• Increases the risk of stroke by 15%

17. blood pressure
inflammation
dyslipidemia
diet /
obesity
ANS dysfunction
metabolic function
physical activity /
sedentary behavior
psychosocial:
stress/anxiety/depression

18. Sleep and
diabetes
Short sleep is associated with diabetes
• People with short sleep duration are ~20-30% higher risk of
type 2 diabetes, compared to people who get sufficient sleep
• Long sleepers are also at a risk
Shan et al. 2015, Diabetes Care

19. Sleep and
diabetes
Short or poor quality sleep leads to reduced insulin
sensitivity (increased insulin resistance)
Reutrakul and Van Cauter, 2018, Metab Clin Exp

20. Short
sleepers gain
more weight
over time
Patel al. 2006, Am J Epidemiol

21. Energy
balance
Obesity is the product of
energy imbalance
At energy balance, intake =
expenditure and weight
remains unchanged
At energy imbalance, intake
≠ expenditure and weight
changes
In positive energy
balance, calories IN
exceed calories OUT, and
body weight gain results
In negative energy
balance, calories OUT
exceed calories IN, and
body weight loss results

22. Sleep and
Obesity
Short sleep can lead to obesity
modified from Reutrakul and Van Cauter, 2018, Metab Clin Exp

23. Sleep restriction increases hormonal drive for appetite/food intake
Intakes Short Sleep Habitual Sleep P value
All (n = 26)
Energy, kcal 2813.6 ± 116.3 2517.7 ± 116.3 0.02
Fat, g 112.2 ± 6.8 91.5 ± 6.8 0.01
Saturated fat, g 36.8 ± 3.5 28.1 ± 3.5 0.04
Carbohydrates, g 402.1 ± 32.6 344.2 ± 32.6 0.19
Protein, g 98.0 ± 4.1 88.1 ± 4.1 0.08
Spiegel et al. 2004, Annals Int Med
St-Onge et al. 2011, Am J Clin Nutr

24. Sleep affects
the brain’s
response to
food
St-Onge et al., 2012, Am J Clin Nutr
Food stimuli compared to non-food
stimuli increased regional brain
activity in the orbitofrontal cortex,
insula, and regions of the basal
ganglia and limbic system after
restricted sleep. (regions involved
in reward processing and decision
making)
Restricted sleep induces a
state of greater
responsiveness to food
stimuli and heightened
awareness of the rewarding
properties of food

25. work sleep
Sleep is normally initiated during the
rising phase of the melatonin curve
and the declining phase of the core-
body temperature curve
SHIFT WORK and
DAYTIME SLEEP

26. Sleep is normally initiated during the rising
phase of the melatonin curve and the declining
phase of the core-body temperature curve
Shift work and jet lag involve “going against”
the endogenous 24-h circadian clock and its
physiology
Shift workers often attempt to sleep during the
rising phase of the core-body temperature
curve and during a time when melatonin
secretion is minimal
Also, attempt to work during times when
alertness levels are low
SHIFT WORK
work
sleep

27. Sleep:
Aging related
changes
Ohayon et al. 2004, Sleep

28. Young adult vs 60 y.o.
WHO

29. Circadian
rhythms:
Aging related
changes
Circadian rhythms become less robust and
slightly phase advanced with old age.
Hood and Amir, 2017 J Clin Investigtion

30. Sleep hygiene:
practices and
habits that are
necessary to have
good nighttime
sleep quality and
full daytime
alertness.
Maintain regular sleep schedule
• Go to bed and get up around the same time every day
(even weekends and vacation)
• Limit naps close to bedtime (recall: sleep
homeostasis); early afternoon better
Sleep environment
• Bedroom quiet, dark, relaxing, comfortable, cool
temperature
• Eliminate light from electronic devices, lamps, etc
• Blackout curtains, eye shades, ear plugs, white noise
machines, fans, etc. to make environment relaxing and
sleep conducive

31. Sleep hygiene:
practices and
habits that are
necessary to have
good nighttime
sleep quality and
full daytime
alertness.
Pre-sleep routine
• Relaxing pre-bedtime routine to help wind down:
• Warm bath/shower (thermophysiological cascade)
• Quiet activities (e.g., reading, music)
• Low lights
• Avoid electronic devices and short-wavelength (“blue”) light
before bed. (change settings, brightness on devices)
• Try to avoid emotionally upsetting conversations and
activities before attempting to sleep (news, social media)
Limit other stimulating activities
• Caffeine/Nicotine: stimulants
• Alcohol: Can help fall asleep but quality disturbed
• Food: Heavy or rich foods, fatty or fried meals, spicy
dishes, citrus fruits, and carbonated drinks can trigger
indigestion/heartburn for some people; limit close to sleep
• Reduce your fluid intake before bedtime.

32. Sleep hygiene:
practices and
habits that are
necessary to have
good nighttime
sleep quality and
full daytime
alertness.
Adequate daytime light exposure
• Together with limited nighttime light exposure, sufficient
daytime light helps maintains proper expression and
timing of the circadian system and sleep-wake cycle
regulation
Exercise
• Even10 minutes of aerobic exercise (e.g., walking or
cycling) can improve nighttime sleep quality.

33. Psychological
& behavioral
approaches for
insomnia
Stimulus control
• Set of instructions designed to reinforce the association
between bed/bedroom with sleep, and to re-establish a
consistent sleep-wake schedule
• Tossing/turning/anxiety about sleep can cause bedtime to
become a conditioned stimulus to trigger a negative response
and further exacerbate poor sleep
• Goal is to (re-) establish a positive association of bed with
sleep at night.
• Bed for sleep!
• Limit the practice of other activities such as eating, reading,
watching television, studying, work, hobbies especially
stressful things in bed
• Go to bed only when sleepy (will associated rapid sleep
initiation with bed)
• If you cannot fall asleep, or you wake up in the night and
cannot fall back asleep, get out of bed and go to a dimly lit
area and do a relaxing activity (read a book, but not something
overly rewarding or fun – don’t want to reinforce being awake)

34. Psychological
& behavioral
approaches for
insomnia
Sleep restriction
• Restrict time in bed (the sleep window) to narrower
range, thereby increasing the homeostatic drive (i.e.,
accumulated sleep debt will fall asleep faster).
• Gradually increase window over days/weeks until
optimal sleep duration is achieved and individual able to
initiate and maintain sufficient sleep
Relaxation training
• Relax both your mind and your body. This helps you to
reduce any anxiety or tension that keeps you awake in
bed.
• Procedures like meditation, progressive muscle
relaxation, etc. to reduce autonomic arousal, intrusive
thoughts, tension interfering with sleep

35. https://drcraigcanapari.com/harnessing-sleep-drive-for-a-better-bedtime/

36. • Sleep as a social determinant of health / sleep disparities research
• COVID-19 and sleep
• Sleep and neurodegeneration / Alzheimer’s disease
• Wearable devices and monitoring of sleep outside the laboratory
• Circadian medicine
• Timing of behaviors (time restricted eating, etc)

37. Insomnia
Symptoms
• Difficulty falling asleep
• Difficulty staying asleep
• Waking up too early
• Feeling that sleep is unrefreshing
• Associated with feelings of daytime
sleepiness, fatigue, difficulty
concentrating, irritable mood
Prevalence
• Affects 30-45% of adults in a given
year.
• 10-15% of adults report chronic
(persistent) insomnia.
• Becomes more common with aging

38. Genetic vulnerability
Physical and psychological arousal
(being “revved up”)
Psychological factors:
depression, stress, anxiety
Insomnia
There are many different causes of
insomnia
Medical or neurological conditions
Behaviors and environment:
work shifts, screen time, light exposure
Substances: Caffeine, alcohol, medications

40. Sleep hygiene: practices and habits
that are necessary to have good
nighttime sleep quality and full
daytime alertness.

41. Psychological
& behavioral
approaches for
insomnia
Stimulus control
• Set of instructions designed to reinforce the association
between bed/bedroom with sleep, and to re-establish a
consistent sleep-wake schedule
• Tossing/turning/anxiety about sleep can cause bedtime to
become a conditioned stimulus to trigger a negative response
and further exacerbate poor sleep
• Goal is to (re-) establish a positive association of bed with
sleep at night.
• Bed for sleep!
• Limit the practice of other activities such as eating, reading,
watching television, studying, work, hobbies especially
stressful things in bed
• Go to bed only when sleepy (will associated rapid sleep
initiation with bed)
• If you cannot fall asleep, or you wake up in the night and
cannot fall back asleep, get out of bed and go to a dimly lit
area and do a relaxing activity (read a book, but not something
overly rewarding or fun – don’t want to reinforce being awake)

42. Psychological
& behavioral
approaches for
insomnia
Sleep restriction
• Restrict time in bed (the sleep window) to narrower
range, thereby increasing the homeostatic drive (i.e.,
accumulated sleep debt will fall asleep faster).
• Gradually increase window over days/weeks until
optimal sleep duration is achieved and individual able to
initiate and maintain sufficient sleep
Relaxation training
• Relax both your mind and your body. This helps you to
reduce any anxiety or tension that keeps you awake in
bed.
• Procedures like meditation, progressive muscle
relaxation, etc. to reduce autonomic arousal, intrusive
thoughts, tension interfering with sleep