What Are Circadian Rhythm Disorders?
A circadian rhythm is your body’s internal 24-hour clock, and it controls your sleep-wake cycle and other body processes, such as eating and digestion. “Circadian” means about a day. Your normal circadian rhythm is set by the cycle of light and dark, along with other factors, over 24 hours.
Circadian rhythm disorders are conditions that disrupt this natural cycle. Several types of circadian rhythm disorders exist, and they can affect how you sleep as well as how you function when you’re awake.
Circadian Rhythm Disorder Symptoms
Your circadian rhythm guides several different body processes. People with circadian rhythm disorders may have symptoms such as:
- Insomnia, or trouble falling asleep or staying asleep
- Waking up too early and not being able to go back to sleep
- Poor sleep quality
- Difficulty waking up
- Daytime sleepiness
- Fatigue
- Headaches
- Depression
- Trouble staying alert
- Stomach problems
Circadian Rhythm Disorder Causes
Your body tries to align your sleep-wake cycle with cues in the environment, especially light and dark. But several things can disrupt your circadian rhythm. Some causes of circadian rhythm disorders include:
- Working overnight shifts
- Traveling from one time zone to another
- Changes in routine, such as staying up late or sleeping in
- Medications
- Stress
- Pregnancy
- Menopause
- Health conditions including Alzheimer's or Parkinson's disease
- Mental health disorders
Circadian Rhythm Disorder Risk Factors
Several factors can make you more likely to develop a circadian rhythm disorder.
Genetics. Certain genes can affect the proteins that control your circadian rhythm.
Neurological disorders. Some diseases and disorders, such as Alzheimer’s disease, attention deficit hyperactivity disorder (ADHD), and autism spectrum disorder, may make you more likely to have circadian rhythm disorders.
Changing work schedules. When the timing of your work shifts changes, it can interfere with your body’s internal clock.
Age. Children and teens are more likely to have a certain type of circadian rhythm disorder (which involves falling asleep late), and adults over age 60 are more likely to have a different type (which involves falling asleep early).
Frequent travel. If you travel across time zones often, it may disrupt your sleep-wake cycle.
Common Circadian Rhythm Disorder Types
Jet lag disorder. This involves symptoms such as too much sleepiness and a lack of daytime alertness in people who travel across at least two time zones. Traveling east usually causes more problems than traveling west, because it’s harder for your body to adjust to going to bed too early than to staying up late.
Shift work disorder. You may be affected by this disorder if you often rotate shifts or work at night. A conflict between someone’s circadian rhythm and the time of their shift can mean they get up to 4 hours less sleep than the average person.
Delayed sleep-wake phase disorder (DSWPD). With this type of disorder, your sleep timing is different. People with DSWPD tend to fall asleep very late at night and have a hard time waking up in time for work, school, or social events. It’s especially common in teens and young adults.
Advanced sleep-wake phase disorder (ASWPD). This is a disorder in which a person goes to sleep earlier and wakes earlier than they wanted. For example, they might fall asleep between 6 p.m. and 9 p.m. and wake up between 1 a.m. and 5 a.m.
Non-24-hour sleep-wake rhythm disorder. This happens when your circadian rhythm is longer or shorter than 24 hours. This disorder often affects people who are blind because the circadian clock is set by the light-dark cycle. It can cause a serious lack of sleep time and quality at night and sleepiness during the day.
Irregular sleep-wake rhythm disorder (ISWRD). With this disorder, people’s circadian rhythms are jumbled. They may sleep in a series of naps over 24 hours. This type can be common in people with certain brain diseases, such as dementia.
Circadian Rhythm Disorder Diagnosis
What should you do if you think you have a circadian rhythm disorder? Talk to your doctor if:
- You sleep poorly for more than 1 month and notice trouble concentrating, forgetfulness, less motivation, or severe daytime sleepiness.
- You have trouble falling asleep.
- You awaken in the morning feeling tired and unrefreshed.
To figure out whether you have a circadian rhythm disorder, your doctor will begin by asking about your symptoms, taking a medical history, and doing a physical exam. They may also ask about any changes in your sleeping and other routines.
Your doctor may also use:
Lab testing. Your doctor might do a blood and urine test, which can tell if you have certain hormone levels that may be causing the disorder and the type of disorder.
Sleep logs. You’ll be asked to write down when and how well you sleep over a certain period. This helps your doctor understand the sleep-wake cycles in your regular environment (when you’re at home and not traveling or working odd hours).
Sleep studies. Usually done in a sleep lab, sleep studies monitor you during sleep, measuring your levels of oxygen, whether and how often you stop breathing, and how much you snore.
Imaging studies. Imaging studies, such as a CT scan and an MRI, can check for neurological diseases, sinus infections, or blocked airways.
Epworth Sleepiness Scale. This questionnaire asks you how likely you are to become sleepy in eight different situations, on a scale of 0-3. Your score measures your sleepiness.
Actigraphy. You’ll wear a motion sensor on your nondominant wrist for several days to track your patterns of rest and activity during that time.
A neurological exam. This tests how your brain and nervous system are functioning.
Circadian Rhythm Disorder Treatments
Your treatment will depend on the type of circadian rhythm disorder and its cause. The goal is to adjust your sleep pattern to fit your lifestyle. Treatments may include:
- Light therapy. Being around a bright light for a certain time each day helps your body reset your circadian rhythm. Sometimes, this involves sitting in front of a light box.
- Chronotherapy. You gradually adjust your bedtime to be earlier or later to reset your circadian clock.
Medications to treat circadian rhythm disorder
In some cases, your doctor may recommend medication to treat circadian rhythm disorders. These medications include:
Melatonin. This natural hormone is made by a gland in the brain at night (when it’s dark out). Melatonin levels in the body are low during daylight hours and high during the night.
Melatonin supplements, available over the counter, may help treat jet lag and sleep-onset insomnia in elderly people with melatonin deficiency. However, they are not regulated as strictly as drugs, as they are dietary supplements and not FDA-approved. So, it isn’t clear how much melatonin is safe and effective.
Melatonin receptor stimulant. Ramelteon (Rozerem), a melatonin receptor stimulant, needs a doctor's prescription. It’s approved by the FDA for treating insomnia marked by trouble falling asleep.
Short-acting benzodiazepines. These drugs, such as Xanax, are often prescribed at the start of treating a circadian rhythm disorder and are used along with behavioral therapy. Long-term use isn’t recommended because of potential side effects, such as the rebound phenomenon (the original problem returns at a higher level) and the risk of dependence.
Nonbenzodiazepine hypnotics. These prescription sleep medications, such as Ambien, Sonata, and Lunesta, aren’t associated with the rebound phenomenon that can happen with benzodiazepines. But the FDA has warned that rare but serious injuries have happened in people taking them, caused by “complex sleep behaviors” such as sleepwalking and sleep driving.
Provigil. If you have circadian rhythm disorder because of shift work, your doctor may prescribe this stimulant. You take it an hour before the start of the work shift to feel more awake.
Circadian Rhythm Sleep Disorder Lifestyle Changes
Changes to your lifestyle and daily habits can help reset your circadian rhythm. You might try these lifestyle changes:
Improve your sleep hygiene. Your doctor may recommend specific changes to your sleep hygiene to treat your circadian rhythm disorder. You can also try things such as establishing a relaxing bedtime routine that you follow every night as you wind down.
Adjust the lights you use. Because bright light helps you wake up, you can try using bright lighting in the morning and dimmer lighting closer to bedtime. Light bulbs that are a bluer white color may be better for daytime, and yellower white light may be better at night.
Set a meal schedule. Having a meal schedule or eating at about the same times each day can help you maintain a sleep schedule.
Exercise regularly. Getting physical activity during the day, but avoiding it late at night, may help.
Avoid certain drinks and substances. Stay away fromcaffeine, alcohol, and nicotine, especially close to bedtime.
How to Prevent Circadian Rhythm Disorders
Circadian rhythm disorders can have many different causes, and some of those causes are things you can’t control, such as your work schedule and health conditions. But other causes, such as frequently changing your sleep routine or staying up too late, are within your control.
Healthy sleeping, eating, and exercise habits can help your body’s internal clock function well, so they may help prevent circadian rhythm disorders.
Takeaways
Circadian rhythm disorders happen when your body’s internal 24-hour clock gets out of whack. Usually, the cycle of light and dark guides your sleep-wake cycles, but several factors can get in the way. If you’re diagnosed with a circadian rhythm disorder, improving your sleep hygiene and making other simple lifestyle changes can help. Your doctor may also recommend other treatments.
Circadian Rhythm Disorder FAQs
How to fix a circadian rhythm disorder
The right remedy for your circadian rhythm disorder depends on your situation, including what’s causing the disorder and what your specific symptoms are. Sometimes, adjusting your sleep schedule will fix a circadian rhythm disorder, while other times, your doctor will prescribe medication, for example.
What is the most common circadian rhythm disorder?
Two of the most common circadian rhythm disorders are jet lag and delayed sleep phase syndrome (DSPS). With DSPS, you tend to fall asleep very late.
How long does it take to reset a circadian rhythm disorder?
Some disorders can be resolved naturally. How long it will take to reset your circadian rhythm depends on your specific situation, what’s disrupting your internal clock, and the type of circadian rhythm disorder you may have. It may take a few days or longer to reset your circadian rhythm.
What improves circadian rhythm disorder?
Sometimes, adjusting your sleep habits can improve your circadian rhythm disorder. But, depending on your symptoms and what’s causing the disorder, your doctor may recommend other types of treatment.
