Sleep Disorders

Advanced sleep phase syndrome is a disorder in which the timing of sleep and the peak period of alertness are advanced several hours relative to societal clock. People with advanced sleep phase syndrome generally have difficulty staying awake unless they go to bed very early because their internal clock is already at a relatively quiet state, and wake up very early, at what is considered a "normal" time in the morning, unable to fall back asleep, because their internal clock is already producing strong alerting signals.

Unless other sleep disorders, such a sleep apnea or insomnia, are present, an individual with advanced sleep phase syndrome sleeps well (in terms of duration and quality) when going to bed and waking up early but the syndrome makes it difficult to stay awake in the evening and be engaged in social activities. Sleep quality is not impaired by the syndrome but afflicted individuals may have short sleep duration if they delay their bedtime. Nonetheless people with advanced sleep phase syndrome do not report that the syndrome affects their daytime work or school activities. Their most common complaint is that their evening activities are cut short by the need to sleep much earlier than what is considered the norm. This can affect family and social relationships. Individuals with Advanced Sleep Phase Syndrome should be cautious about driving in the late afternoon and evening, because they may be too drowsy. They also do not adjust well to evening or night shifts.

The prevalence of advanced sleep phase syndrome in the general population is unknown although it is most prevalent among older adults. Advanced sleep phase syndrome has the same prevalence among men and women. Researchers have also found a strong genetic link: 40%-50% of people suffering from advanced sleep phase syndrome are related to someone who has the syndrome.

Learn more about circadian sleep disorders.

Most people don't seek treatment unless it starts to significantly impact their social life. Sleep specialists treat advanced sleep phase syndrome with evening bright light exposure.

Bright light therapy is used to manage circadian rhythm disorders such as delayed sleep phase syndrome (DSPS), a condition which shifts the normal sleeping pattern outside what is considered the social norm. People who have DSPS generally don't fall asleep until several hours after midnight and have trouble waking up in the morning, making adhering to a normal work or school schedule difficult. However, if allowed to follow their own schedules, their quality of sleep is otherwise normal.

Bright light therapy is used to gradually shift sleeping patterns to what we consider normal. For treatment, the timing of light exposure is critical. For DSPS, the light must be delivered to the retina as soon after spontaneous awakening as possible to achieve the desired effect. People have also reported success with lights that turn on shortly before awakening, to simulate dawn. Morning use may also be effective for non-24-hour sleep-wake syndrome, while evening use is recommended for advanced sleep phase syndrome. There is less data about the effectiveness of light therapy for advanced sleep phase syndrome than there is for morning light exposure in delayed sleep phase syndrome.

This technique—also called phototherapy—uses appropriately timed exposure to light to help delay the patients biological clock. The source of light could be artificial, such as a full spectrum lamp at 10,000 lux or portable visor at lower light intensity or, when reliably available at the right time, natural outdoor light. Longer properly timed light exposure is better, with recommended exposure duration of 30-90 minutes. The ideal timing of the light exposure depends on the best approximation available of the persons circadian clock.

The sleep specialists works with the patient to decide on the timing of the light exposure based on patients symptoms and life circumstances. The specialist may start by recommending light exposure take place shortly before the patients usual time of spontaneous awakening.

The specialist helps the patient slowly shift the sleep period to an earlier time. After the desired sleep schedule is attained patients should maintain a fixed rise time (even on weekends and vacations) and ideally continue to use morning light exposure on most mornings, though the duration of light exposure can be shorter. Specialists often recommend using dim lights in the evening in conjunction with bright light exposure in the morning during the advancement of the sleep schedule.

For maintenance, some patients continue the treatment indefinitely, while some reduce their daily treatment to 15 minutes. Others may use the lamp a few days a week or even every other or third week. The degree of success is different for each patient. Light therapy generally adds a little extra time to the morning routine. If you have a family history of macular degeneration, you should consult with an eye doctor prior to starting bright light therapy.