What is advanced sleep-wake phase disorder?

Advanced sleep-wake phase disorder (ASP) is one of several circadian rhythm sleep-wake disorders. These disorders occur in people who sleep at times that seem to be out of order with “normal” sleep times. People with ASP have an “early bird” circadian clock. They fall asleep several hours before a normal bedtime. As a result, they also wake up hours earlier than most people wake in the morning.

People with ASP feel sleepy in the late afternoon. Bedtime tends to occur between 6 p.m. and 9 p.m. Since bedtime is early, they also wake up early. They tend to wake up between 2 a.m. and 5 a.m. While the timing of sleep is early, sleep itself is normal.

All the biological changes related to sleep also occur at early times. This includes an earlier release of melatonin and other hormones. The body temperature curve is also moved earlier. This has been used as a marker to detect this disorder.

Some people with ASP can follow this early schedule. Problems often occur when social plans take place during the late afternoon or evening. This makes them struggle to stay awake. They may appear very sleepy to others during these evening hours. Missing a few hours of evening sleep over time can cause chronic sleep deprivation. This results in true sleepiness. Even when deprived of sleep, people with ASP still tend to wake up early.

People with ASP may mistake their problem for something else. They may think that waking up too early is a sign of either insomnia or depression. They may worry about being awake so early. It is hard for them to be awake at a time when others are asleep.

People with ASP may adjust their lifestyles or jobs around their natural “early bird” clock. For example, an “early bird” clock would be ideal for working the early shift. This includes jobs such as a baker or surgeon. Other people with ASP do things to worsen their condition. They try to realign their early clock to match the schedules of others. For example, they may drink too much coffee or take stimulants to stay awake at night. They may also try to stay asleep during the morning hours. To do this, they may drink alcohol or take sleeping pills. These choices will only make their sleep worse.

What are symptoms of advanced sleep-wake phase disorder?

Someone with ASP may:

  • Fall asleep during the late afternoon or early evening AND wake up too early while everyone else is still sleeping
  • Feel very sleepy in the late afternoon AND very alert in the early hours of the morning
  • Awaken and fall asleep before they would like toIt is also important to know if there is something else that is causing your sleep problems. They may be a result of one of the following:
  • Another sleep disorder
  • A medical condition
  • Medication use
  • A mental health disorder
  • Substance abuse

What are risk factors for advanced sleep-wake phase disorder?
Advanced sleep-wake phase disorder is not very common. It is estimated to occur in only 1% of middle-age adults. It is more common in older adults and seniors. Men and women are affected at an equal rate. A genetic link has been shown in some families and may be the cause of ASP in younger patients. ASP may be caused, increased, or maintained by environmental factors. It can also result from outside social or work pressures.

How to diagnose advanced sleep-wake phase disorder?
ASP is a sleep disorder that may or may not cause symptoms. You may be able to adapt your lifestyle to the early schedule. If so, then you should not need treatment. This early sleep time is often out of line with the schedules of others. You may not be able to adapt your job or social life to your “early bird” clock. This may lead you to try things that will make your sleep problem worse. This “early to bed, early to rise” schedule may cause severe sleepiness. It may also lead to problems with family, friends, or work. If this is the case, then you should talk to your medical provider.

You’ll be asked about your medical history. Your family history may also provide important details. You may be asked to complete a sleep diary over several weeks. This will show the times when you normally go to sleep and wake up. You may be asked to rate your sleep with a simple questionnaire. This will help show how your sleep is affecting your daily life. Be sure to inform the doctor of any past or present drug, alcohol, and medication use. Also tell the doctor if you have ever had any other sleep disorder.

Detecting ASP can be done through an office visit with details from your sleep diary. A sleep study should not be needed although it may be used if you are at risk for other sleep disorders. The sleep study is called polysomnography. It charts your brain waves, heartbeat, oxygen levels, and breathing as you sleep. It also records how your arms and legs move. This shows if there are other sleep disorders that are causing or increasing your sleep problems. Examples of these disorders include sleep apnea and periodic limb movement disorder. Since you go to sleep and wake up early, the sleep study should be performed during the early sleep times. If you do not have another sleep disorder, then the sleep study should show your sleep to be normal.

You may be asked to use an actigraph at home. This is a device that you wear on your wrist. It records your sleep activity over a period of one to two weeks. Other methods of testing could be used. This might include ongoing monitoring of your body temperature. Your melatonin levels may also be measured by testing your saliva, but these tests are mostly used for research.

How to treat advanced sleep-wake phase disorder?

ASP may or may not need to be treated. People with ASP often adapt their lifestyles to an early schedule. If you can do this, then you shouldn’t have any sleep problems, but problems may occur if you try to follow a later schedule.

Sleep doctors first try to help patients adjust to their “early bird” clocks. This is done through education and behavioral counseling. For example, people with ASP should not make plans to do things late at night. You should not work the late afternoon or evening shifts. You should not use caffeine or stimulants in the evening. This will only worsen your sleep. You should not use alcohol or drugs to stay asleep during early-morning hours.

Another treatment option is bright light therapy during the early evening hours. Light therapy can help you “re-set” a clock that is off. Regular sleep patterns help to keep the clock set at the new time. ASP is treatable and most people can arrange their activities so they can be alert and participate fully in whatever they wish to do.

Reviewed by:  Seema Khosla, MD and Rafael Sepulveda, MD

This New Year, make your dental health a priority. Embrace the opportunity for a fresh start and join us at Beacon Dental Clinic in making 2024 the year of a confident, healthy smile.

Schedule your appointment today and let’s embark on this dental wellness journey together.