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Why Delayed Sleep Phase Disorder Is Different from Being a Night Owl

Lots of people occasionally have trouble falling asleep, staying asleep, or both. There are also specific disorders that relate to disturbances in your circadian rhythm and make waking up in the morning difficult. Delayed sleep phase disorder (DSPD), also known as delayed sleep phase syndrome, is the most commonly diagnosed circadian rhythm sleep disorder.

DSPD is not just staying up late at night once in a while. Delayed sleep phase syndrome involves persistent late-night sleep times because of an inability to fall asleep at a normal time. People with DSPD often have trouble waking up in the morning. DSPD is a common disorder that can begin at any age but usually starts during puberty and continues into adulthood. 

Most people experience occasional late nights, but people with DSPD go to sleep two or more hours later every night. For instance, the average adult might go to bed at 11:00 p.m. and wake at 7:00 a.m. A person with DSPD will not fall asleep until 1:00 a.m. or later but is still expected to be up and alert at 7:00 a.m. to go to school or work. This lack of sleep can disrupt your ability to function properly.

Everyone has a slightly different sleep schedule based on their work/school schedule, responsibilities, and other family members’ schedules. People with this sleep disorder are commonly referred to as “night owls,” but they don’t stay up late and/or sleep late in the mornings by choice.

People with DSPD are often diagnosed with insomnia. But if they are allowed to follow their internal clock, they do not experience insomnia. When people with delayed sleep phase disorder are allowed to follow their body’s natural sleep schedule, they normally sleep well and feel rested when they wake up. 

Many teenagers and young adults stay up late because of social activities or time needed to study and then sleep in on weekends. For most people, this sleep-wake pattern returns to an “acceptable” schedule when not necessary or desired. However, if a person continues to experience symptoms into adulthood, it could be DSPD. Delayed sleep phase syndrome can include the following symptoms.

This disorder does not involve the inability to fall asleep. It is the inability to fall asleep at a conventional or socially acceptable time.

Later sleep times and later wake times are associated with DSPD and can be among the most bothersome. Because a person diagnosed with this sleep disorder falls asleep at a later time each night, it is much more difficult to wake up in the morning.

These symptoms tend to be the most reported by people with delayed sleep phase syndrome. Because people with this sleep disorder go to sleep later than most, it is hard for them to conform to others’ schedules. Having to wake up earlier than their body wants to can cause excessive daytime sleepiness. Many people with DSPD complain of difficulty focusing, particularly at midday, because of a lack of sleep.

Children and adolescents diagnosed with DSPD may also experience bouts of depression and other psychiatric problems. These problems can include behavioral problems stemming from a lack of sleep, daytime drowsiness, frequent tardiness, and missed days of school. The inability to stay focused in school because of daytime drowsiness can lead to reduced academic performance and a potential dependence on caffeine, sedatives, or alcohol.

Researchers don’t yet know the exact cause of this sleep disorder. It may be related to genetics, and parents should be aware that this behavior is not a deliberate act to disobey rules or be defiant. There are contributing factors that can increase the symptoms associated with this syndrome. It can be helpful to avoid these factors, which can further disrupt your sleep pattern, especially if you have DSPD. 

  • Environmental factors such as exposure to bright evening sunlight 
  • Lack of exposure to morning sunlight (extremely dark room)
  • Excessive use of electronic devices in evening hours

To provide an accurate diagnosis, your health care provider will review your family and medical history. A family history of DSPD is common in about 40 percent of people diagnosed with this disorder.

Your health care provider may do a physical examination and order specific tests to diagnose DSPD or other related conditions. These tests could include the following:

  • Actigraphy — Measurements made by a small wearable device that tracks your sleep-wake behavior and phases
  • Sleep diary — Your health care professional may ask you to keep a sleep diary. This usually includes information about when you go to sleep and wake up. This will help record your sleep-wake patterns throughout the week and on weekends.
  • Polysomnogram — This test may be ordered to determine if you have a different sleep disorder other than DSPD. Polysomnograms are typically performed overnight at a sleep center. Your health care provider will use various devices to monitor vital signs (heart rate, respiration, and blood pressure), oxygen levels, snoring, eye movements, and brain activity while you sleep.

Once your health care provider has collected the necessary information, they will work with you to develop a plan to improve your delayed sleep phase. This plan may include:

  • Improving sleep habits — This is often referred to as sleep hygiene. Good sleep hygiene means maintaining a regular sleep schedule that includes consistent sleep and wake times throughout the week. 
  • Avoiding caffeinated drinks, food, and stimulating activities near bedtime
  • Avoiding tobacco products and alcoholic beverages later in the evening 
  • Using the bedroom and bed for sleeping and sex only. Health care providers suggest that the bedroom should not be used to watch TV or play video games before bedtime. 
  • Avoiding moderate to vigorous exercise late in the day (mild exercise, such as a walk in the evening, might be helpful for some)
  • Melatonin supplements — Melatonin is a naturally occurring hormone made by a small gland in the brain (pineal gland). Your body releases this hormone to control sleep-wake patterns. This over-the-counter supplement has been used for years to help people adjust to different time zones while traveling (jet lag) and help people sleep. Your health care provider may suggest taking this sleep aid in the early evening to help regulate your circadian rhythm.
  • Bright light therapy — Bright light that mimics sunlight in the morning may help adjust (or reset) your internal sleep clock to achieve a more conventional sleep schedule.
  • Chronotherapy — This process is a time-delayed therapy that gradually adjusts your sleep schedule. The goal of chronotherapy is to delay your sleep schedule by 1 to 2.5 hours every six days. This process is continued until you reach the desired effect and bedtime.

Good-quality sleep is important for your health. Your body works best when you have consistent sleep-wake patterns and enough sleep. Some people’s sleep phase is shifted by their natural internal clock (circadian rhythm), causing delayed sleep phase disorder. This is not insomnia; people with DSPD do not have trouble falling asleep or staying asleep. People with DSPD have a sleep pattern that does not conform to conventional sleep schedules, causing problems with work performance, afternoon drowsiness, midafternoon focus issues, and potentially, behavioral issues and depression. If you are experiencing the symptoms associated with this sleep disorder, speak with your health care provider about the best treatment options for better sleep.







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