Advanced Sleep Phase Syndrome:
Advanced sleep phase syndrome is a circadian rhythm disorder that causes someone to go to sleep earlier in the evening and wake earlier in the morning, compared to most people.
Individuals with this condition typically feel excessive sleepiness in the early evening and go to bed early as a result. They may complain that they wake early in the morning and cannot get back to sleep.
It occurs more often in the elderly and also seems to run in families. It may be a symptom of depression. It can be diagnosed with the use of sleep logs and actigraphy and can also be effectively treated with light box phototherapy, behavioral therapy, and melatonin use.
Example: Edith is a 78-year-old woman who often becomes sleepy around 7 p.m. and typically goes to bed by 8 p.m. She wakes up at 4 a.m. and cannot get back to sleep. She would prefer to sleep in until at least 6 a.m. and typically spends the first few hours of her mornings lying in bed awake.
Learn more about circadian rhythm disorders.
American Academy of Sleep Medicine. "International classification of sleep disorders: Diagnostic and coding manual." 2nd ed. 2005.