How common is advanced sleep phase syndrome?

This question was asked in Irvine, California on 02/02/2012.
My 63 year old wife has been on a very unusual sleep pattern for almost a year. She becomes very sleepy in the early afternoon and falls asleep. But then she wakes up very early in the morning around 1AM or 2AM and doesn't fall back to sleep even though she remains tired. Could this be advanced sleep phase syndrome?

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Doctors Answers (2)

Richard J. Schumann Jr., MD
Answered on: 2/2/2012 2

As a sleep disorder it is fairly uncommon but is seen mostly in the elderly. This disorder of advanced sleep phase syndrome (ASPS) affects the body's circadian rhythm or internal pacemaker for the sleep/wake cycle. In this case, a phase advance of the sleep cycle to an earlier clock time has occurred. The body's internal pacemaker is governed by light exposure, the most potent cause of this type of shift. Therefore, too much light exposure in the morning is likely the case here. Exposure to bright light near a normal bedtime (for about 2 hours) and avoiding daytime naps for several days with reentrain the time clock and treat this syndrome leading to a normalization of sleep time. Also, the main differential diagnosis for ASPS is depression. this should also be considered.

J. Douglas Hudson, MD, DABSM
Answered on:

Advanced sleep phase syndrome (going to bed very early and arising very early) is an uncommon disorder, affecting approximately 1% of adults. It affects both genders equally, has a higher rate of occurrence in the elderly population and has a strong genetic link. As many as 40-50% of people with Advanced Phase Syndrome will have a familial link to the disorder.