Symptoms and Treatments of Circadian Rhythm Disorders

Irregular Sleep Patterns May Cause Insomnia, Excessive Daytime Sleepiness

Circadian rhythm sleep disorders lead to symptoms of insomnia and sleepiness and respond well to treatments including light therapy and melatonin
Circadian rhythm sleep disorders lead to symptoms of insomnia and sleepiness and respond well to treatments including light therapy and melatonin. Christopher Furlong / Getty Images

Difficulties falling asleep or staying awake at the proper times may suggest you have a problem with your biological clock called a circadian rhythm disorder, but what are circadian rhythm disorders? These common conditions may include wanting to sleep at an atypical time, irregular sleep patterns, and even jet lag or shift-work sleep disorder. Discover how these disorders contribute to symptoms of insomnia, poorly timed sleepiness, and effects on daytime function.

Review the most effective treatments, including light therapy and melatonin.

Features and Symptoms of Circadian Rhythm Disorders

The circadian rhythm disorders share common characteristics. They occur when your internal biological clock becomes out of sync with external time cues such as the natural dark-light cycle. As a result, your desire to sleep may shift away from nighttime when most people naturally sleep. Therefore, you may have difficulties with insomnia or excessive daytime sleepiness. The inability to sleep at the expected time coupled with sleepiness during wakefulness may lead to difficulties with job and school performance. For a better understanding of this, review the disorders and examples provided below:

Characterized as night owls, people with delayed sleep phase syndrome often have difficulty falling asleep. This insomnia may result in a natural ability to fall asleep that is closer to 2 to 4 AM.

It is also extremely difficult to wake up, resulting in profound morning sleepiness. The preferred wake time may be observed on weekends or days off and is usually from 10 AM to Noon. It is estimated that about 7% of people are night owls, and it usually begins in teenagers and can persist throughout life.

About 40% of night owls will have a family history of the disorder.

The opposite of night owls, people with advanced sleep phase syndrome are sometimes describes as being morning larks. They fall asleep very early and wake too early as well. This advance in the timing of sleep is usually 3 hours earlier than typical. For example, someone who is affected may fall asleep at 7 PM and wake by 3 AM, far earlier than desired. This condition may affect 1% of adults and can be confused with other causes of early morning awakenings such as sleep apnea.

Non-24 rarely occurs in sighted people, but it affects 50 to 73% of blind people. In the absence of effective synchronization of their internal clock with light exposure, they run a day-night pattern that is determined genetically and often runs a little long. For example, the internal clock might run at 24 1/2 hours in length. Therefore, the desire for sleep and waking occurs 30 minutes later each day.

This results in a shifting sleep schedule with increasing insomnia and daytime sleepiness that unfolds over several weeks as the misalignment continues.

Though the exact prevalence is unknown, people with neurologic disorders like dementia or children with intellectual disability may more likely experience an irregular sleep-wake rhythm. This may be worsened among those who are institutionalized with inadequate exposure to natural day-night light patterns. It seems to occur when the circadian rhythm degenerates or becomes unmoored from natural influences. Sleep becomes very fragmented, often with 3 or more periods of sleep lasting a few hours and scattered throughout the 24-hour period. Irregular bouts of sleep may be accompanied by insomnia and excessive daytime sleepiness complaints. The total amount of sleep is often normal.

Jet lag occurs after travel across multiple time zones. Its intensity may depend on the length of the trip and how quickly the travel occurs. It is generally easier to travel shorter distances, slower, and in a westward direction. It takes about 1 day to adjust to each time zone crossed. Beyond trouble with insomnia and sleepiness, jet lag can also contribute to symptoms of malaise (feeling unwell) and an upset stomach.

People who work when they are meant to be asleep are at risk of having difficulty sleeping during the daytime and trouble staying awake during the night. This can have important safety consequences with increased risks of accidents. There also may be long-term effects, such as an increased risk of developing colorectal and breast cancer among shift workers.

Diagnosis and Treatment of Circadian Rhythm Disorders

Circadian rhythm sleep disorders often result when the desire to sleep is misaligned with the day-night cycle. This may occur in medical conditions such as blindness or as the result of long-distance air travel or even from working the graveyard shift. Fortunately, the conditions are easily diagnosed by using sleep logs and actigraphy and effective treatments including behavioral changes, light boxes, and melatonin can be helpful.

If you feel like you may be suffering from the ill effects of a circadian rhythm disorder, speak with a board-certified sleep physician about your concerns and discover the effective treatment that you need.

Source:

American Academy of Sleep Medicine. "International classification of sleep disorders: Diagnostic and coding manual." 2nd ed. 2005.

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