Sleep problems in teenagers – delayed sleep phase disorder

by Dr. Theodric Lee

Johari* is a 13 year old boy who seeks help for difficulty waking up in the mornings for school. He used to sleep at 11pm but since the Circuit Breaker (partial lockdown in Singapore 7 Apr – 1 Jun 2020 due to the COVID-19 pandemic) he has been sleeping at 2am. When school resumed, he tried to sleep at 11pm but is unable to sleep till 2am and his parents have great difficulty waking him up for school at 6am in the morning. Teachers have given feedback that he falls asleep in class. During weekends he goes to bed at 2-3am and sleeps in till 10-11am.

The above is a typical case of delayed sleep phase disorder, which is a persistent phase shift in the body clock (circadian rhythm) affecting school or work schedule. This is known to affect about 5-15% of teenagers, and may cause daytime sleepiness, behavioural and academic problems. In this condition (in contrast to other causes of insomnia), the teenager has no problems sleeping and waking late at his or her preferred time (during weekends and holidays). People who are more alert in the evening (this is often referred to as an “eveningness” chronotype) may be at higher risk of developing delayed sleep phase disorder as compared to those who are more alert in the morning (“morningness” chronotype). Online morningness-eveningness questionnaires are now available for self-testing.

Management of delayed sleep phase disorder in the sleep wellness clinic

  • Education of sleep hygiene measures. These include limiting the use of the bed for sleep only (i.e. no homework or smartphone in bed); limiting the time in bed worrying about sleep; avoidance of bright lights (including screen time) 1-2 hours before bedtime; appropriate bedtime routines; avoidance of caffeine (including soft drinks).

  • Addressing any co-existing anxiety or mood disorders (if these are present, would require a psychologist or psychiatrist to manage as well).

  • A personalised and scheduled gradual shifting of the body clock (circadian rhythm) – this has to be done in small steps as it is very difficult to shift in large steps. This is usually done in combination with:

    • light therapy - using the effect of sunlight or specialised light glasses to shift the circadian rhythm. (Caution: this has to be done under the instruction of a specialist as bright light exposure at the wrong time may worsen the disorder.)

    • Medication for difficult-to-treat cases


*not his real name