01 Jun Delaying High School Start Times Promotes Student Health and Performance: An American Academy of Sleep Medicine Position Statement
The American Academy of Sleep Medicine (AASM) recently published a position statement on school start times for middle school (age 11-13) and high school (age 14-18).
This was prompted over concerns with apparent impairment in physical and mental health in this age group. During adolescence there are changes in internal circadian rhythms and biological sleep drives resulting in later sleep and wake times.
A growing body of evidence shows that delaying school start times positively impacts student achievement, health, and safety.
The AASM therefore created this new position statement.
The AASM asserts that school start times should be 8:30AM, or later to support:
- An adequate opportunity for adolescents to obtain sufficient sleep on school nights
- Optimal alertness in the classroom environment to facilitate peak academic performance
- Reduced tardiness and school absences to foster improved opportunities for learning
- Adolescent mental health and psychological well-being
- Adolescent driving safety
As children progress into their teenage years, they experience delayed patterns of melatonin secretion and a slower buildup of homeostatic sleep pressure during wakefulness. These changes reflect a delayed circadian rhythm that contributes to later sleep onset and later morning awakening, with teenagers typically struggling to fall asleep before 11:00PM.
The AASM recommends that teenagers 13 to 18 years of age should sleep 8 to 10 hours per 24 hours on a regular basis to promote optimal health, and this recommendation has been endorsed by the American Academy of Pediatrics and Sleep Research Society.
Because sleep onset is not instantaneous, a teenager who goes to bed at 11:00PM would need to sleep until 7:30AM, or later, in order to obtain sufficient sleep. Early start times work contrary to this change in adolescent circadian physiology and truncate students’ sleep opportunity, resulting in chronic sleep loss. Presently, 68% of USA high school students sleep 7 hours or less on school nights, while only 23% sleep 8 hours, 6% sleep 9 hours, and 2.4% sleep 10 hours or more.
No comparable studies have been performed in Australia, however one study found 45% of teens aged 14 to 16 regularly sent texts after 3am, and 75% after midnight. Some were sending more than 100 texts a night. However it’s not only sending the texts that’s part of the equation; the anticipation of waiting for a reply to a text means the brain wakes up – a term called “infomania”. Teenage girls in particular suffer FOMO (fear of missing out) if they turn their device off overnight. They’d rather suffer tiredness than arrive at school, into their peer group, being the only one who wasn’t up with the nocturnal electronic goings-on.
Short sleep in adolescents is associated with poor school performance, obesity, metabolic dysfunction and cardiovascular morbidity, increased depressive symptoms, suicidal ideation, risk-taking behaviours, athletic injuries, and increased motor vehicle accident risk. Increased MVA risk is particularly concerning because young, novice drivers have a higher crash risk when sleep deprived, and MVA crashes account for 35% of all deaths and 73% of deaths from unintentional injury in teenagers in the USA.
For young drivers/riders in Queensland studies demonstrated ~15% of the licensed driver/rider population were aged 17-24 years; 20% killed on the road were aged 17-24 years; and 86% of young adult road users were judged to be at fault in the crash.
In addition this change would have beneficial impacts on teenage students, including longer total sleep time, reduced daytime sleepiness, increased engagement in classroom activities, and reduced first-hour absence. Delayed school start times also are associated with reduced depressive symptoms and irritability. Reaction time improves, and crash rates decline by 16.5%, following a school start time delay of 60 minutes. Extension of sleep time also facilitates behavioural weight loss interventions.
While a change in school start times does not assure longer sleep durations, this change coupled with educational materials regarding the importance of sleep in school curricula, is likely to motivate students, teachers, and parents to prioritize sleep and implement healthy sleep practices, including:
- Sleeping in a cool, dark, quiet sleep environment
- Sleeping for an adequate time : 8 to 10 hours of sleep per night
- Consistent bedtimes and wake times on weekdays and weekends
- A regular bedtime routine to cue the body that sleep is imminent
- Regular morning light exposure
- Avoiding the use of sleep-disrupting electronic devices near bedtime or during the night. Studies have confirmed blue wavelength light emitted from electronic devices suppresses the production of melatonin and contribute to difficulty falling asleep.
These practices will benefit the student, regardless of school start time. In Australia, we are just starting to have schools instituting “sleep hygiene lessons” as part of life-skills programs, where students are taught a routine to get ready for bed.
Parents of students who are experiencing extreme difficulty awakening to arrive at school on time, or who experience significant daytime sleepiness, should consider scheduling a consultation with their child’s GP to evaluate for a sleep disorder, regardless of the student’s school start time.
References: Delaying middle school and high school start times promotes student health and performance: an American Academy of Sleep Medicine position statement. Journal Clin Sleep Med. 2017;13(4):623–625.
State of the Road: A Fact Sheet of the Centre for Accident Research & Road Safety – Queensland (CARRS-Q) www.carrsq.qut.edu.au/publications/corporate/novice_drivers_fs.pdf