Circadian Rhythm Sleep Disorders

Circadian rhythm disorders can happen for a variety of reasons and may be rooted in mental or physical health conditions. Sometimes, there is a misalignment between the internal body clock and external time.

But while most scheduling problems can be corrected with the simple tweak of a watch or calendar, getting your internal clock back on track is a bit more challenging. Circadian rhythm disorders can be temporary or they can easily become chronic, leading to issues even bigger than just falling asleep and waking up at the right time.

In this article, we’ll explore the most common circadian rhythm sleep disorders, what causes them, and some ways that you can reset your body’s clock to make the most of your days — and nights too.

Understanding the Circadian Rhythm

Humans are creatures of habit, but it seems that we come by that tendency naturally.

The circadian rhythm is the output of the body’s internal clock. In fact, the word circadian, which comes from Latin, is a combination of the words “circa” and “diem,” meaning “about a day.”

For humans, the various circadian rhythms are entrained by their body clock. The body’s time is set by the suprachiasmatic nucleus in the hypothalamus, which acts as the master clock.

The sleep-wake cycle is one such circadian rhythm, along with hormonal and temperature rhythms. The master clock in the brain manages the hormones and body temperatures that support our sleepiness and alertness throughout the day.

Light is key in setting and maintaining circadian rhythms. Our eyes receive light from the sun and other sources and send a message to the brain, which coordinates the body’s response, including the production of melatonin.

Other environmental cues, called zeitgebersVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source, also influence the timing of our sleep-wake rhythm, such as light, meals and exercise schedules. Light is considered the primary zeitgeber for the circadian clock.

“Light is one of the strongest ‘time signals’ for our clock,” says Dr. Nayantara Santhi. “For most of us, our daily light exposure includes predominantly indoor artificial light, which is constantly available.”

“This is cause for concern, because of the effects of light on our circadian clock and the health consequences of disruption of circadian rhythmicity and associated sleep deprivation through exposure to artificial light. Making sure we have enough outdoor natural light during the day and limiting artificial light after dark can go a long way in reducing circadian disturbances and accompanying sleep disruption.”

Circadian Rhythm Disorders

While most of us follow the natural rhythms of our environment without a problem, there are times that our sleep-wake cycles do not align. When the body’s circadian rhythm is off – especially when it’s by a few hours – sleep especially is impacted.

There are several key issues related to circadian rhythm disordersVerified Source Cleveland ClinicRanked #2 hospital by U.S. News & World Report and one of the largest academic medical centers in America. The Cleveland Clinic serves patients from all over the world.View source:

• Having trouble falling asleep at the desired time.
• Waking throughout the night or struggling to stay asleep.
• Waking up too early and struggling to fall asleep
• Waking up feeling unrested, due to sleep that wasn’t restorative.

Circadian Rhythm Sleep Disorders

On the whole, circadian rhythm sleep disorders are fairly rare, affecting 3 to 10 percentVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source. However, some people are more at risk than others:

• Teenagers
• Older individuals
• People who travel over long distances
• Those who work overnight or constantly change shifts

Below are some of the most common circadian rhythm disorders.

Delayed Sleep-Wake Phase Disorder

For people with Delayed Sleep-Wake Phase DisorderVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source (DSWPD), going to sleep at a “normal” time is a challenge.

People with DSWPD may be more awake, productive, and even creative at night later than most people. If they have to get up early–as they often do due to their responsibilities and obligations–they’re likely to experience fatigue throughout the day, and they may struggle with responsibilities and tasks that pop up in the morning.

Genetics may play a factorVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source in who has DSWPD. It is also very common in teens and young adults, affecting as many as 16% of teensVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source. Because of this, the American Academy of Pediatrics recommends that high schools postpone the start of classes until 8:30 a.m.Verified Source American Academy of Pediatrics (AAP)Professional society for pediatricians that aims to improve children’s health everywhere.View source or later.

By all estimations, DSWPD wouldn’t necessarily be a problem if the timing of waking life and sleep didn’t conflict. Left to their own devices, people with DSWPD would likely sleep as much as their peers, even if at slightly different times. However, work, family, school, and social demands rarely allow this schedule to be achieved, creating issues with sleep.

Advanced Sleep-Wake Phase Disorder

As with DSWPD, Advanced Sleep-Wake Phase Disorder (ASWPD) makes it difficult to fall asleep and wake up at a normal time. But while those with DSPS stay up extremely late, people with ASPS typically struggle to stay awake until the “right” time for bed, waking up early the next morning as well. The timing of the sleep-wake cycle is often off by two or more hours compared to the norm.

People with ASWPD would likely achieve consistent, full sleep if they were allowed to pursue this natural schedule. However, as with DSWPD, daytime responsibilities and obligations, which more often follow the typical sleep-wake schedule, usually get in the way.

ASPS is rare, but becomes increasingly common with age and genetics may again play a factorVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source.

Jet Lag

Anyone who has traveled across three or more time zones by air, especially if they were heading east, has likely experienced the circadian rhythm disorder known as jet lagVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source.

With jet lag, the body’s internal clock, which may be right on time at home, is at odds with the daytime patterns in the new location. This mismatch disrupts the circadian rhythm, making it a challenge to sleep at the right time in either time zone.

Traveling to the east is more likely to cause jet lag than traveling to the west, as it’s typically easier to stay up late than to fall asleep early. The more time zones you cross, the more severe your symptoms are likely to be.

The symptoms of jet lagVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source include tiredness and fatigue, changes in appetite and mood, gastrointestinal discomfort, headache, and a general feeling of uneasiness. A few factors can make these symptoms worse:

• Age (the older you are, the longer recovery may be)
• Sleep deprivation
• Long periods of discomfort (as with sitting in an airplane seat)
• Changes in air quality and pressure
• Stress
• Excessive caffeine use
• Exposure to light at the wrong times

The good news is that jet lag is temporary, though the effects are immediate and its severity depends on several factors, such as the number of time zones that have been crossed.

Shift Work Sleep Disorder

When you, like millions of Americans, don’t work a standard nine-to-five schedule or your work times are constantly changing, you might be at risk for Shift Work Sleep DisorderVerified Source Cleveland ClinicRanked #2 hospital by U.S. News & World Report and one of the largest academic medical centers in America. The Cleveland Clinic serves patients from all over the world.View source (SWSD).

Inconsistent schedules make it difficult for the body clock to establish sleep-supporting patterns. Likewise, an inverted sleep-wake schedule that requires you to be  alert at night and sleep during the day is likely to throw off the body’s natural clock. Even worse, trying to sleep during the day–when everyone around you is awake–is a challenge in itself, making it even more difficult to get the deep rest you need.

The symptoms of SWSDVerified Source Oxford AcademicResearch journal published by Oxford University.View source include:

• Insomnia
• Tiredness/fatigue
• Moodiness and irritability
• General unease and discomfort
• Gastrointestinal changes
• Increased risk of accidents
• Excessive daytime sleepiness

Over time, shift work disorder can increase the risk of serious health concerns, including weight gain, high blood pressure, heart disease, certain cancers, and reduced fertility. Comorbidities such as medical, psychiatric, or other sleep conditions may further raise these risks.

SEE ALSO: Shift Work Sleep Disorder (SWSD), Diagnosis & Treatments

Irregular Sleep-Wake Rhythm Disorder

With an irregular sleep-wake rhythmVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source, the sleep-wake cycle–and essentially, the circadian rhythm–is not defined. This often results in sporadic sleep patterns, often with a series of naps occurring over the course of 24 hours rather than one long period of sleep.

Symptoms of ISWRD frequently include insomnia and excessive daytime sleepiness. The condition is common in people with neurological conditions and injuries, such as dementia, intellectual disabilities, or traumatic brain injuries.

Non-24-Hour Sleep-Wake Syndrome

Described as “free-running,” Non-24-Hour Sleep-Wake DisorderVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source (N24) occurs when a person’s internal clock runs for longer than 24 hours.

Typically, people with N24 enjoy regular sleep-wake times. However, because those cycles occur on a schedule longer than 24 hours, sleep time starts a little later every day, often shifting by an hour or two.

Non-24 Hour Sleep-Wake Syndrome is common in people who are blindVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source, as they do not process light in the same way that seeing people do. The absence of light as a trigger to manage and regulate sleep and wake times forces or allows the body to find its own rhythm.

What Causes Circadian Rhythm Disorders?

For some circadian rhythm issues, the the causes are clearVerified Source Cleveland ClinicRanked #2 hospital by U.S. News & World Report and one of the largest academic medical centers in America. The Cleveland Clinic serves patients from all over the world.View source: travel, unusual work schedules, brain damage, being a certain age. In a general sense, interrupted sleep patterns, especially when severe or continual, are often to blame.

In addition to frequent changes in sleep and waking times, poor sleep hygiene is a common cause for circadian rhythm disorders. Too much light–especially blue light from devices– in the afternoon and evenings, inconsistent bedtimes, and failing to create a comfortable sleep environment can all contribute to poor sleep, which can, in turn, contribute to circadian rhythm disorders.

Symptoms of Circadian Rhythm Sleep Disorders

Sleep deprivation is one of the most common consequences of circadian rhythm sleep disorders, as people often do not get enough quality sleep as a result of the condition. That lack of sleep, in turn, leads to a number of symptoms that can significantly reduce a person’s quality of life. These include:

• Insomnia
• Excessive daytime sleepiness
• Problems with waking up at the right time
• Reduced mental and physical health
• Strained personal and social relationships
• Poor performance at school or work
• Increased risk of accidents and mistakes

Diagnosing Circadian Rhythm Sleep Disorders

Any time sleep issues begin to negatively impact your life, you should discuss your concerns with a doctor. They will likely gather information about your sleep patterns, medical history, work, and lifestyle to identify possible causes and rule out any other sleep or medical disorders.

For circadian rhythm sleep disorders, your daily melatoninVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source levels may be measured, or you could be asked to keep a sleep diary. A sleep diary is a log of your sleep and activity around sleep, including how long it takes you to fall asleep, how many hours you spent in bed, and what times you fell asleep and woke up. An actigraphy device may further help to record your sleeping and waking patterns.

Another test that your doctor may recommend are sleep studiesVerified Source Medline PlusOnline resource offered by the National Library of Medicine and part of the National Institutes of Health.View source. In this study, also called polysomnographyVerified Source Medline PlusOnline resource offered by the National Library of Medicine and part of the National Institutes of Health.View source, a specialist monitors your sleep, breathing, and brain activity while you sleep. While most sleep studies occur at night, they can often be tailored to your individual sleep schedule. For shift workers, that may mean a daytime sleep study.

Treatment for Circadian Rhythm Sleep Disorders

Lifestyle changes, good sleep hygiene, and light therapy are among the most common treatments for circadian rhythm disorders, as they all introduce and support the cues that help our bodies to reset according to the calendar day. In some circumstances, medication may also help.

Lifestyle Changes

For many, correcting an offset circadian rhythm starts with taking a hard look at how your lifestyle is affecting your sleep and making changes as needed. Some of the ways that you can support good sleep and reset your body clock include:

• Shifting schedules to support sleep, whether changing a work or school schedule, timing your eating, and allowing sufficient time to wind down in the evening before bed.
• Avoiding naps during waking hours, as these attempts to catch up on rest can backfire at bedtime.
• Managing light exposure by avoiding bright and blue lights in the evening before bed.

Good Sleep Hygiene

Engaging in good, consistent sleep hygiene is one of the most important ways you can support sleep, no matter what’s causing your issues. Our tips to sleep better include:

• Establishing consistent sleep and wake times, even on weekends and holidays, to fix a sleep schedule.
• Exercising regularly and eating well. See our guide on the link between regular exercise and sleep.
• Creating a positive sleep environment that is clutter-free, cool, and includes a comfortable mattress, pillows, and bedding.
• Avoiding caffeine in the afternoon and evenings. See our article on how much caffeine is in coffee.
• Engaging in a routine before bed, particularly if it includes relaxing activities to help you settle into sleep.

It’s also important to not force sleep; if you’re having trouble drifting off, it’s better to get up and do something relaxing until you’re sleepy again.

Bright Light Therapy

Because light is essential to managing our circadian rhythms, light therapy, or the intentional regulation of our exposure to light, can help us to get those rhythms back on track.

Light in the early morning helps kick off our day with peak alertness. Many people benefit from intentional exposure to light using a light therapy box in the early hours of the day.

In the evenings, even overhead bedroom lightsVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source can delay the production of melatonin, the hormone that helps us sleep. With the onset of dusk, you’ll want to start dimming those lights. And, of course, put away your devices. The blue light from our phones and televisions is incredibly problematic for sleep.

Chronotherapy

Essentially, chronotherapyVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source is time therapy. Undergoing chronotherapy may involve a progressive shifting of your sleep schedule, slowly delaying or advancing your sleep to move it toward the desired schedule. You may also delay or advance your meal schedule, your medicine schedule, and other daily routines.

Chronotherapy introduces a new sleep-wake schedule over time, allowing your body to ease into it rather than forcing (and likely failing) to adapt all at once. Once the desired schedule is achieved, it’s essential that you stick with it, letting your body settle into the pattern of sleep you’ve created.

Medications

When all else fails, your doctor may recommend the use of certain medications and supplements to help you manage your sleep issues. These can include both prescription and over-the-counter medications as well as natural supplements to help you sleep better and at the right times.

Frequently Asked Questions

What is a parasomnia?

Parasomnias are sleep-related disorders that disrupt an individual’s lifestyle. There are two types of parasomnias, non-REM parasomnias and REM parasomnias.

Non-REM parasomnias include night terrors, sleepwalking, confusional arousals, and sleep-related eating disorder. REM parasomnias include nightmare disorder, sleep paralysis, and REM sleep behavior disorder.

What causes a circadian rhythm disorder?

Circadian rhythm disruptions can be temporary, caused by travel across time zones or a  change in a person’s working schedule. Poor sleep habits, such as late-night exposure to blue light through electronic devices, are another potential cause for a sleep disorder. Developing sleep habits can help a person get their sleep schedule back on track.

However, certain genes can determine whether an individual has an easier time falling asleep late or waking up early. While it’s possible for an individual with a preference for a late night’s rest to work hard and become an early riser, there is no way to change genetics.

How do I reset my circadian rhythm?

Consistency is a key part of resetting your circadian rhythm. Waking up at the same time every day will help you fall asleep at the same time every night.

Watching your light exposure will also help your brain understand when it’s time to be awake and when it’s time to go to bed. Getting sunlight exposure in the morning promotes wakefulness, while shutting off your bright electronics at night helps your brain realize it’s time to go to bed.

Are blind individuals at risk of circadian rhythm disorders?

Yes, people who are blind or otherwise visually impaired may develop sleep disordersVerified Source National Library of Medicine (NIH)World’s largest medical library, making biomedical data and information more accessible.View source be cause they are not taking in light that is crucial to their circadian rhythms. The most common disorder for patients who cannot see at all is non-24-hour sleep-wake disorder, a condition that affects up to 50 percent of blind patients without light perception.

Diagnosing a blind individual with a sleep disorder is a complicated process, with doctors relying on detailed clinical history and the patient’s sleep diaries.

How do you fix a circadian rhythm disorder?

Treatment depends on the severity of your circadian rhythm disorder. The most common treatments include bright light therapy, melatonin supplements or receptor agonists (such as tasimelteon and ramelteon), and lifestyle changes.

Recommended lifestyle changes include following a regular eating and sleeping schedule, regular exercise, and limited caffeine intake.

Conclusions

When the body’s internal clock is at odds with the environmental clock, it can wreak havoc on our sleep schedule. Circadian rhythm disorders include Delayed and Advanced Sleep-Wake Phase Disorders, jet lag, Shift Work Disorder, and more, all of which can make it difficult to sleep and wake up at the right times.

Through adjustments to your sleep activities and hygiene, you may be able to reset the clock on sleep, allowing you to make the most of your schedule and even improve your quality of life too.