8. Jul, 2015

High School Student's Need Later Start Times

 “I have to battle with my teenager every morning to get them out of bed and off to school.” Sound familiar? 

Did you know adolescents have biologically different sleep and wake patterns compared to the preadolescent or adult population? In adolescents secretion of melatonin (sleep hormone) begins at around 10.45pm and continues throughout the night until about 8 am. This means that adolescents are unable to fall asleep until melatonin secretion begins and they are also not able to wake up until the melatonin secretion stops. 

In the early 1990’s medical research found that adolescents have biologically different sleep and wake patterns compared to the preadolescent or adult population. Professor Mary Carskadon is a leader in the field of adolescent sleep research and has written extensively on the subject.

In one of her recent papers 'Adolescent Changes in the Homeostatic and Circadian Regulation of Sleep' it was noted that “Adolescent changes in the timing of sleep reflect a developing circadian and homeostatic system. Our work indicates that teenagers have a slower accumulation of sleep drive in response to sleep deprivation, as well as an internal clock that interprets environmental time cues differently from adults. These results have several important implications."

Prof Carskadon noted that for doctors "these results emphasise the need for differential diagnostic considerations when treating sleep and circadian disorders in adolescents. This appears especially important for the diagnosis of circadian phase disorders, such as delayed or advanced sleep-phase disorders, as well as for insomnia and narcolepsy.” So although it may seem like an adolescent is showing signs of Idiopathic Hypersomnia, Narcolepsy or Delayed Sleep Phase Disorder it could actually be normal behaviour as a result of the natural biological changes in adolescent sleep-wake patterns.

What does this mean in simple terms? The changes in adolescence body clocks mean that their waking and sleeping times can get later and later. The problem is school start times require teenagers to be awake much earlier than their body clock would have them wake naturally. As a result, they tend to suffer the consequences of insufficient sleep eg: daytime sleepiness, changes in mood and behaviour, poor judgement, difficulty concentrating etc. Studies show that adolescents who don’t get enough sleep have a decline in academic performance, they often suffer physical and mental health problems and they are also at an increased risk of car accidents.

"Chronic sleep loss in children and adolescents is one of the most common – and easily fixable – public health issues in the U.S. today,” said paediatrician Judith Owens, MD, FAAP, lead author of the policy statement, 'School Start Times for Adolescents' published in the September 2014 issue of Paediatrics.

"The research is clear that adolescents who get enough sleep have a reduced risk of being overweight or suffering depression, are less likely to be involved in automobile accidents, and have better grades, higher standardized test scores and an overall better quality of life”

However, these changes to your teenager's sleep/wake pattern are dramatic and beyond their control. Just expecting them to go to bed earlier is not the answer.

Dr Owens said, “Studies have shown that delaying early school start times is one key factor that can help adolescents get the sleep they need to grow and learn.”

As a result of the research in a policy statement published online in 2014, the American Academy of Paediatrics (AAP) recommended middle and high schools delay the start of class to 8:30 am or later. They found that doing so will align school schedules to the biological sleep rhythms of adolescents, whose sleep-wake cycles begin to shift up to two hours later at the start of puberty.

Australian schools have been slow to acknowledge this problem. There are high schools in Australia that are known to start as early as 7.15am. An urgent need to consider the natural changes to adolescent biological sleep rhythms and change school start times accordingly is necessary.

Check out this link http://www.teen-sleep.org.uk for easy to read information on why sleep is important to adolescents and what you can do to help your child get a better night’s sleep.

Image Credit: Derrivative of 'Sleeping in School' by MC Quinn(CC BY 2.0)