What is Delayed Sleep Phase Disorder (DSPD)?

NewsGuard 100/100 Score

Delayed sleep phase disorder (DSPD) is the most common circadian rhythm sleeping disorder, involving an abnormal alignment of the sleep-wake cycle causing the affected individuals to feel sleepiness and wake up later than what is considered normal.

delayed sleep phase disorderImage Credit: eldar nurkovic/Shutterstock.com

The sleep phase is classified as delayed if it is misaligned by more than two hours of what is considered normal. This means that most people with DSPD begin to feel tired between 1 a.m. and 4 a.m. and wake up in the late morning or afternoon.

Although the exact causes of DSPD are unknown, it is very common and affects up to 15% of adolescents and young adults. It is thought to be associated with lack of morning sunlight exposure or overexposure to bright light in the evening, due to the effect of light on the circadian rhythm.

Symptoms of delayed sleep phase disorder

Symptoms indicative of delayed sleep phase disorder include:

  • Absence of tiredness at normal bedtime
  • Inability falling asleep at normal bedtime
  • Difficulty waking up at a normal time
  • Excessive sleepiness during the day

If individuals with DSPD are able to sleep according to the delayed cues of their body, they will continue to get enough sleep and will live relatively uninhibited lives. When allowed to go to sleep later and wake up later, they continue to get enough sleep and are able to live and function normally.

However, most individuals have particular commitments, such as school or work, in the morning that may restrict the time that they are able to sleep. Individuals may then experience sleep deprivation and related symptoms, such as sleepiness during the day and decreased performance at school or work.

Up to half of individuals with the disorder also suffer from depression, which is likely associated with the negative symptoms of sleep deprivation.

Diagnosis of delayed sleep phase disorder

Delayed phase sleep disorder is usually diagnosed based on symptoms reported by the patient. A sleep diary can be a useful tool to record sleep habits and identify patterns such as DSPD, which may be affected the health and overall performance of the individual.

In some cases, an autograph to monitor sleep-wake cycles can be worn by patients to confirm the diagnosis. Additionally, polysomnography can also help to monitor the sleep stages of an individual and detect particular differences between sleep disorders.

3 What is delayed sleep phase disorder

Management of delayed sleep phase disorder

For people who experience negative effects as a result of DSPD, it is important to take steps to minimize the impact of the disorder. The recommended management of DSPD involves techniques to adjust the circadian rhythm of the individual and advance it, so it is more closely aligned to what is considered normal.

Initially, this may include intentionally going to bed slightly earlier each night, allowing the body to adjust to the changes in the timing of sleep. This can be effective in some cases, but relies on the self-control of the individual and can revert back easily if the individual diverts from the new habit.

Other treatment techniques that may be used to advance the sleep phase include:

  • Bright light therapy in the early morning
  • Dark light therapy at night and before bed
  • Pharmacotherapy to aid sleep (e.g. melatonin)

With these techniques, many individuals are able to advance their sleep schedule by up to two hours, although it is difficult to go beyond this point. It is worth noting that not everyone with DSPD will require treatment if they are able to meet their sleep needs within their daily schedule.


Further Reading

Last Updated: May 24, 2021

Yolanda Smith

Written by

Yolanda Smith

Yolanda graduated with a Bachelor of Pharmacy at the University of South Australia and has experience working in both Australia and Italy. She is passionate about how medicine, diet and lifestyle affect our health and enjoys helping people understand this. In her spare time she loves to explore the world and learn about new cultures and languages.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Smith, Yolanda. (2021, May 24). What is Delayed Sleep Phase Disorder (DSPD)?. News-Medical. Retrieved on June 13, 2024 from https://www.news-medical.net/health/What-is-Delayed-Sleep-Phase-Disorder-(DSPD).aspx.

  • MLA

    Smith, Yolanda. "What is Delayed Sleep Phase Disorder (DSPD)?". News-Medical. 13 June 2024. <https://www.news-medical.net/health/What-is-Delayed-Sleep-Phase-Disorder-(DSPD).aspx>.

  • Chicago

    Smith, Yolanda. "What is Delayed Sleep Phase Disorder (DSPD)?". News-Medical. https://www.news-medical.net/health/What-is-Delayed-Sleep-Phase-Disorder-(DSPD).aspx. (accessed June 13, 2024).

  • Harvard

    Smith, Yolanda. 2021. What is Delayed Sleep Phase Disorder (DSPD)?. News-Medical, viewed 13 June 2024, https://www.news-medical.net/health/What-is-Delayed-Sleep-Phase-Disorder-(DSPD).aspx.


The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.
Post a new comment

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.

You might also like...
Sleep apnea linked to higher hospitalization rates in older adults