The diagnosis of circadian rhythm disorders is challenging and often requires
a consultation with a sleep specialist. Keeping a detailed sleep history and a
sleep log for 1 to 2 weeks is essential. It is also important to exclude other
sleep and medical disorders, including narcolepsy, which often mimics delayed
sleep phase disorder.
Narcolepsy is a sleep disorder in which people experience excessive daytime
sleepiness and uncontrollable episodes of falling asleep during the daytime
despite adequate sleep.
Sleep diaries are often complemented by actigraphy, a method of
recording sleep and wake using a wrist motion monitor for a period of days to
weeks. Overnight and daytime sleep testing may be required. Sleep studies must
be tailored to address the sleep pattern of the individual. This may require
that testing be performed at unconventional times, for example, an ‘overnight’
sleep study might be performed during the day in a shift worker.
Treatment Options
Treatment options for circadian rhythm disorders vary based on the type of
disorder and the degree to which it affects the individual’s quality of life.
Individualizing the treatment of patients of circadian rhythm disorders improves
the chance of success. Treatment options include:
Behavior Therapy such as maintaining regular sleep-wake times, avoiding naps,
engaging in a regular routine of exercise, and avoiding caffeine, nicotine, and
stimulating activities within several hours of bedtime is important in the
treatment of circadian rhythm disorders. People with delayed sleep phase
syndrome should minimize exposure to light in the evening and during the night
by reducing indoor illumination and avoiding bright TV and computer screens.
Those with advanced sleep phase syndrome should increase light exposure in the
evenings by keeping lights on in the home or spending time outdoors.
Bright Light Therapy is used to advance or delay sleep. The timing of this
treatment is critical and requires guidance from a sleep specialist. Bright
light therapy works by resetting the circadian clock. A high intensity light
(10,000 lux) is required and the duration and timing of exposure varies from 1 to 2 hours.
Medications such as melatonin, wake-promoting agents, and short-term sleep
aids may be used to adjust and maintain the sleep-wake cycle to the desired
schedule. Melatonin is a hormone that is available over-the-counter and is
particularly effective in treating jet lag.
Chronotherapy is a progressive advancement or delay (1 to 2 hours per day) of
sleep time depending on the type and the severity of the disorder. This type of
therapy requires a firm commitment on the part of the patient and caregiver as
it is can take weeks to successfully shift the sleep-wake cycle. Once the
desired schedule is achieved, a regular sleep-wake schedule is maintained.
References
Avidan, Alon Y; Zee, Phyllis C. Handbook of Sleep Medicine. 1st edition.
Philadephia: Lippincott Williams and Wilkins. May 2006.
Foldvary-Schaefer N. The Cleveland Clinic Guide to Sleep Disorders. New York:
Kaplan Publishing, 2009
Sack, Robert L; Auckley, Dennis; Auger, R. Robert, et al. Circadian Rhythm
Sleep Disorders: Part I, Basic Principles, Shift Work and Jet Lag Disorders. An
American Academy of Sleep Medicine Review. Sleep. 2007 November 1; 30(11):
1460–1483. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2082105/. Accessed June 8, 2010
Circadian Sleep Disorders, Other. Sleep Education.com.
http://www.sleepeducation.com/Disorder.aspx?id=63. Accessed June 8, 2010