Delayed Sleep Phase Syndrome

What Is Delayed Sleep Phase Syndrome (DSPS)?

Delayed sleep phase syndrome (DSPS) is a disorder in which a person’s sleep is delayed by two hours or more beyond what is considered an acceptable or conventional bedtime. The delayed sleep then causes difficulty in being able to wake up at the desired time.

For example, a person with DSPS may fall asleep after midnight instead of at 10 p.m. and then will have difficulty getting up in the morning for school or work.  

The effects of DSPS

People with delayed sleep phase syndrome generally have difficulty:

• Falling asleep, unless they go to bed very late (usually some hours after midnight) because their internal clock is sending alerting signals until late into the night
• Waking up at a "normal" time in the morning, because their internal clock is not yet producing strong alerting signals

Unless you have other sleep disorders, such a sleep apnea or insomnia, you may actually sleep well with DSPS, in terms of duration and quality of sleep. The problem is that the delay makes it difficult to wake up in time for a typical school or work day.

How do I know if I have delayed sleep phase syndrome?

You may have DSPS if the sleep disorder is also causing impairment in social, occupational or other areas of your life. The prevalence of DSPS among adolescents and young adults is approximately seven to 16 percent.

DSPS may develop in early childhood but most commonly it emerges or worsens during adolescence. Some adolescents delay their sleep schedules for social reasons and may not have underlying abnormalities in their circadian rhythm (the internal body clock). For those, sleep schedules normalize in early adulthood. Learn more about circadian sleep disorders.

Treating delayed sleep phase syndrome

If you have been unsuccessful in changing your sleeping pattern on your own, it may be time to seek the help of sleep disorder specialists. Our sleep specialists use two treatment methods to treat DSPS:

• Bright light therapy: We use light to gradually shift your sleeping pattern to a more conventional schedule. Learn more about bright light therapy
• Chronotherapy: This technique aims to reset your circadian clock by slowly delaying your bedtime (and your sleep period) by about two hours every few days. We use this strategy less frequently than the light therapy method. The disadvantage is that it disrupts your normal schedule of activity during the shift, when day and night are reversed.