Why are we so sleepy? Focus Fall 2017 Conference 37 th Annual Michael Aiello Memorial Respiratory Care & Sleep Medicine Poughkeepsie, NY Dr. Steven A Thau MD Director, Pulmonary and Sleep Medicine Phelps Memorial Hospital/Northwell Health
Before Electricity and the Light Bulb!
The first demonstration of a circadian rhythm by Jean Jacques d Ortous de Mairan in 1729 Princ & Prac Sleep Med 2011
Free Running Mice, Monkeys and Humans
Why Do We Sleep? Much of our life is spent sleeping. <2 years old >half their time spent asleep 2-5 years old half their time spent asleep adults 1/3 of our time spent asleep The function of sleep remains unknown but the benefits are very real.
Why Do We Sleep? Rechtschaffen and colleagues demonstrated that rats deprived of sleep lost weight, despite eating more, and died in 10-30 days. Pathology was inconclusive. Randy Gardner in 1965 stayed awake for 11 days and then slept for 14 hours without ill effects.
Why Do We Sleep? Memory Reinforcement - dream deprivation decreases ability to learn new things Synaptic and Neuronal Network Integrity - areas not stimulated during the day are stimulated randomly at night. This helps maintain connections.
Sleep Stages
Sleep Stages Stage N1: lightest sleep; slow rolling eye movement; brain wave activity slightly slower; easily arousable (truck drivers can do this and drive); makes up <10% Stage N2: deeper than stage one; brain activity slower than stage 1; you know you were asleep; fairly easy to arouse; makes up ~50% Stage N3: deepest sleep; hard to arouse; usually confused when the patient wakes; makes up ~1-15%; decreases as we get older Wake: makes up less than 10% of sleep Movement: makes up less than 5% of sleep REM: rapid eye movement ~25%
REM SLEEP Atonia Rapid-Eye Movement Phasic muscle and EEG activity Irregular Breathing & HR Dreaming, more vivid than non-rem Erection Poikilothermic
How Much Do We Need?
sleep, hrs Sleep Stages Across the Life Cycle 20.0 15.0 10.0 5.0 quiet REM deep light 0.0 new born 3-5 mo 6-23 mo 2-3 yrs 3-12 yrs 13-18 yrs 19-45 yrs 50-70yrs
Sleep, hrs How Much Sleep Do We Need? Data from Dr Carskadon, Dr Mirmiran, Dr Buttross, Dr Ferber & Dr Czeisler 16 14 12 10 8 6 4 2 0 new born 3-5 mo 6-12 mo 1-3 yrs 3-5 yrs 5-10 yrs 13-18 yrs 19-45 yrs 50-70 yrs
How Much Do We Need? Adults need on average 8 hours of sleep <10% need < 6 hours Adolescents ~ 9 hrs Children ~ 10 hours Infants ~ 14 hours It can take two weeks before sleep requirements stabilize
How Much Sleep Do We Need? Roehrs et al 96 Performed a study on 12 volunteers. They were placed in bed for 10 hours for two weeks. Initially, patients slept > 8 hrs, by Day 14 average time asleep was 8.6 +/- 0.6 hrs. MSLT s (nap studies) were performed. Initially most subjects were sleepy. Following 14 days of sleeping ~8+ hours daytime sleepiness resolved
How Much Sleep Do We Need? Wehr et al 93 studied 12 individuals for 1 wk with 8 hr nights then 4 wks 14 hr nights. During extended sleep period: 1 st week ~ 9-11 hours of sleep 2 nd 3 th weeks ~ 9 hours of sleep 4 th week ~ 8 hours of sleep Extensive work by M. Carskadon (Brown University) & C. Czeisler (Harvard) consistent with these studies.
How Much Sleep Do We Get? Sleep, 2015 Ford et al; Survey 324,243
How Much Sleep Do We Get? Sleep, 2015 Ford et al; Survey 324,243
How Much Sleep Do We Get? NSF poll 2005 Age 18-29 30-49 50-64 65+ Number 177 616 426 273 <6 hrs 13% 17% 16% 14% 8+ 30% 24% 25% 30% Avg 6.8 6.7 6.7 6.9
THEREFORE The average US adult is sleep deprived! Including this doctor/speaker!
And the Kids Are Worse!
What are the Effects of Sleep Deprivation? Weight Gain Poor Grades Mood Change Decreased Athletic Performance Kills
Sleep deprivation = Weight Gain Van Coulter, University of Chicago Young Men Sleep Deprived for 6 days Increased Ghrelin Decreased Leptin Eat More Processed Carbohydrate
Sleep Deprivation = Poor Grades Survey 3,000 high school students done by Bown University Students getting C, D or F s avg 30 min less sleep a night Harris Poll 2,300 high school students Students getting C, D or F s vs A B students 2X more likely to daydream, fall asleep in class and have difficulty with attention
Sleep Deprivation and Memory Nilsson et al 89 studied the effects of age, ETOH and sleep deprivation on memory. Methods: 30 young adults randomly divided into control, intoxicated (0.06 gm/dl) or 26 hrs 0 sleep. In addition there was a group of 10 ~69 y/o subjects. Measured ability of subjects to recall paired lists of words. Some pairs highly related i.e. fast dog, others poorly related cup pizza
% Correct Sleep Deprivation and Memory 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Nilsson et al 89 Strong Pairs Control Older ETOH No Sleep
% Correct Sleep Deprivation and Memory Weak Pairs 80% 70% 60% 50% 40% 30% 20% 10% 0% Control Older ETOH No Sleep Nilsson et al 89
Sleep Deprivation and Memory Nilsson et al 89 Conclusion: Subjects that were older, sleep deprived or intoxicated demonstrated significant impairment in the recall of weakly paired words. In strongly paired words only sleep deprivation and ETOH decreased recall.
Sleep Deprivation & Mood Sleep Deprived Military Recruits (18-23) Sleep Deprivation 5 hours sleep/night for 1 week Increased Tension-Anxiety Depression-Rejection Fatigue-Inertia Confusion-Disorientation
Studies imposing sleep deprivation for 3 5 nights in college athletes found: Less motivation in practice Greater sensitivity to pain More sensitive to poor performance
Sleep Deprivation & Reaction Time Asian Journal of Sports Medicine, Volume 3 (Number 1), March 2012, Pages: 15-20
Sleep Deprivation and Injuries 160 middle / high school students records were checked for injuries. Age 12 18, average 15 Correlated a number of habits with the risk of injuries. Diet, grades, caffeine, drug use, sleep amongst some of the questions.
Sleep Deprivation and Injuries J Pediatr Orthop. 2014 Mar;34(2):129-33. Milewski MD1 et al.
Sleep Deprivation: 1 Night Sleep Deprivation <<< Several Nights Affects Hormone Levels Causes Weight Gain Ability to Learn studying videos Less Motivation, Pain Tolerance, Mental Toughness - especially in practice Lower Reaction Times Lower Accuracy More Likely to Get Injuries
In a study of 10,000,000 people. Allen Pack, U. Penn, 1995 >60% of accidents involve adults < 25 yrs old >60% of accidents occur between 11PM and 8 AM Driving Drowsy
Driving Drowsy 51% of adolescents who drive report that they have driven drowsy in the past year 16% of 11 th graders and 20% of 12 th graders drive drowsy once a week or more.
Avoid Drowsy Driving Call someone to pick you up if the driver (you?) is sleep deprived or sleepy. UBER/LYFT! Take a nap / drink caffeine before driving if tired Drive with another driver DO NOT rely on rolling down the window, turning up the radio, chewing gum etc THEY DON T WORK Tell your parents or teacher if you are experiencing frequent daytime sleepiness or having difficulty sleeping at night
Sleep Deprivation = the effects of being intoxicated with alcohol. Don t get into the car of someone who is sleep deprived. If you drive: Remember: Drive Alert. Arrive Alive