Delayed Sleep Phase Syndrome

What is delayed sleep phase syndrome?

Delayed sleep phase syndrome (DSPS) is a condition that affects your ability to fall asleep and wake up on time. The delay in your sleep schedule is off by at least two hours. This condition affects your internal clock.

As an example, rather than falling asleep at 10 p.m. and waking at 6:30 a.m., a person with delayed sleep phase syndrome will fall asleep well after midnight and have trouble getting up in time. If they were to keep a sleep diary, it would show short sleep periods during the school or work week (with few or no awakenings during the night) and lengthy sleep-ins (late morning to midafternoon wake-up times) on the weekend.

Most people with DSPS describe themselves as “a night owl“ or an evening person, but they’re not. If you have DSPS, you’re not able to regulate when your body tells you to fall asleep. If you’re a night owl, you don’t have severe daytime dysfunction (daytime sleepiness) as seen with DSPS.

You may hear your healthcare provider call this condition delayed sleep phase syndrome or delayed sleep-wake phase disorder.

What kind of sleep disorder is delayed sleep phase syndrome?

Delayed sleep phase syndrome is a type of sleep disorder called a circadian rhythm sleep disorder. Your circadian rhythm is a 24-hour cycle that helps you stay awake during the day and fall asleep at night. This cycle regulates how certain parts of your body function, like your body temperature and digestion.

What are the types of delayed sleep phase syndrome?

There are two types of delayed sleep phase syndrome characterized by when the sleep hormone (melatonin) signals your circadian rhythm. This signal (onset) tells your internal clock that it’s time to go to sleep:

• Circadian aligned: The melatonin onset is less than two hours before you fall asleep.
• Circadian misaligned: The melatonin onset is more than two hours before you fall asleep or it doesn’t happen until after sleep begins.

What are the symptoms of delayed sleep phase syndrome?

Symptoms of delayed sleep phase syndrome include:

• Not falling asleep at the desired bedtime aligned with societal norms.
• Difficulty waking up at the desired time aligned with societal norms.

This can lead to:

• Severe daytime sleepiness.
• Trouble with memory, focus and concentration.
• Behavioral and/or mood changes like irritability.

DSPS symptoms can be difficult to differentiate from other hypersomnolence sleep conditions (conditions that make you feel tired during the daytime) like narcolepsy and idiopathic hypersomnia.

What causes delayed sleep phase syndrome?

Delayed sleep phase syndrome has a genetic cause. Healthcare providers can’t test for these genes, but many people feel empowered knowing that their symptoms are the result of a genetic change in their DNA rather than “laziness.”

Research suggests that the genetic component makes your body’s natural circadian rhythm longer than average. This can affect your body’s desire to fall asleep at a scheduled time.

What makes delayed sleep phase syndrome worse?

Some things that may make your symptoms of delayed sleep phase syndrome worse include:

• Jet lag.
• Extended bed rest.
• An irregular sleep schedule.
• Unhealthy sleeping habits (like drinking caffeine before bedtime).
• Too much light exposure before bedtime and too little light exposure in the daytime.

What are the risk factors for delayed sleep phase syndrome?

Delayed sleep phase syndrome is more common among adolescents and teenagers. This is because your body’s natural circadian rhythm changes during puberty.

The condition can also affect adults and is common among women and people assigned female at birth between the ages of 40 and 60. One study found that an estimated 90% of adults diagnosed with DSPS had symptoms of DSPS when they were children.

You’re more likely to have DSPS if you have a biological family history of the condition.

What are the complications of delayed sleep phase syndrome?

Delayed sleep phase syndrome may cause the following complications:

• Depression: Your ability to sleep can affect your mood and stamina. Over 60% of people diagnosed with delayed sleep phase syndrome experience depression.
• Substance use disorder: Many people who have DSPS overuse caffeine, sedatives or alcohol to help them stay awake or fall asleep.

In addition, DSPS can affect your performance during school or work and it can cause tardiness or missed attendance of important events.

How is delayed sleep phase syndrome diagnosed?

To diagnose delayed sleep phase syndrome, a healthcare provider or sleep specialist will ask you to describe your symptoms and keep a sleep diary or sleep log. A sleep log is a record of the time when you:

• Go to bed.
• Fall asleep.
• Wake up.

It helps to keep a notepad and pen near your bed so you don’t forget to record the time. The time when you fall asleep should be an estimate you write down in the morning, as you won’t be able to realistically write down the exact time when you fall asleep. Your healthcare provider will let you know how long you need to keep a sleep log.

To confirm a diagnosis, your healthcare provider may ask you to wear a device called an actigraph that records cycles of rest and activity. This can confirm what times you fall asleep and wake up. You can wear this device for seven to 14 days.

In addition, your provider might perform dim light melatonin testing (DLMO), polysomnography (PSG or sleep study) and a multiple sleep latency test (MSLT). These tests help differentiate DSPS from other hypersomnia conditions.

Common sleep disorders like obstructive sleep apnea can make the presentation of DSPS worse, so a healthcare provider may diagnose and treat that condition as well.

How is delayed sleep phase syndrome treated?

A healthcare provider may recommend the following to treat delayed sleep phase syndrome:

• Changing your sleeping habits
• Adjusting your bedtime schedule.
• Light therapy.
• Taking medications.

Changing your sleeping habits

A healthcare provider may recommend the following changes to your sleep routine:

• Keep your bedroom or sleeping area cool. For example, don’t use a heavy comforter in the summer months or run a low-noise fan in your room.
• Close curtains or blinds to keep light out of your sleeping area. You can also wear an eye mask to keep out unnecessary light while you sleep.
• Relax before getting into bed. You might take a warm bath, for example.
• Turn off electronic devices like cell phones, televisions or video game consoles an hour before bedtime. Certain devices emit a blue light that interferes with how your body handles the sleep hormone melatonin.
• Stick to the same sleep schedule on weekdays and weekends. This includes on vacations and holidays.
• Avoid caffeinated food and beverages like coffee, chocolate and tea in the evening and especially before bedtime.
• Avoid consumable stimulants like alcohol and nicotine or stimulating activities like high-intensity exercises one hour before bedtime.

It can be difficult to make changes to your nighttime routine that you’ve likely followed for years. To make this change easier, take one or two new habits and incorporate them into your routine until they become natural. Then add one or two more. Easing into change may help you adapt better than changing all of your habits at once.

Adjusting your sleeping schedule

Adjusting your sleeping schedule works by anchoring your wake-up time. If your body is used to a certain schedule, it can take time to retrain your body to adjust to a new one. The focus is to advance your wake-up time, which then advances your sleep onset at bedtime. There are two methods you can try to shift your sleeping schedule:

• Advancing your internal clock: You can move your bedtime a few minutes earlier each night until you reach your desired bedtime. For example, setting your bedtime at midnight on one night, 11:45 p.m. on the next night, 11:30 p.m. on the following night and so on.
• Delaying your internal clock (chronotherapy): You can move your bedtime one to three or more hours later on successive nights until you reach your desired bedtime. For example, your bedtime changes daily from midnight to 8 a.m., 3 a.m. to 11 a.m., 6 a.m. to 2 p.m., until you reach your goal, which may be 11 p.m. to 7 a.m. This requires several days free from social activities or commitments. You might choose to attempt this change during a vacation or break from school or work. The thinking behind this strategy is that it’s much easier for your body to adjust to a later bedtime than an earlier one.

It's especially important to stay motivated and stick to your goals. While it’s easy to lose sight of your bedtime on weekends and holidays, your internal clock only stays on time if you train it to. Adhering to strict bed and wake times keeps your body’s internal clock regulated but doesn’t “cure“ the tendency toward a delayed sleep-wake phase. After several months of sticking to a schedule, you might allow yourself some flexibility on special occasions.

Light therapy

Some healthcare providers recommend light therapy as a treatment for delayed sleep phase syndrome. You’ll need to purchase a special light box to participate in light therapy. You’ll turn on the light for half an hour in the morning. This can help your body’s internal clock reset. Your healthcare provider will give you recommendations and instructions on what light box to purchase and how to use it.

An alternative approach your provider might suggest is to get 30 minutes of sun exposure outdoors after waking up. Another helpful approach to lights is to reduce light exposure from electronic devices in the evening hours as well.

Medication for delayed sleep phase syndrome

Your healthcare provider may recommend taking an over-the-counter melatonin supplement to help shift your circadian rhythm. Your body naturally produces melatonin to regulate your sleep-wake cycle. A gland in your brain (pineal gland) secretes the highest levels of melatonin during the night. You might need a little extra melatonin to help you meet your desired sleep schedule.

Your healthcare provider will recommend an appropriate dosage of melatonin. For example, a low dose (0.5 to 1 mg) is a starting treatment. This isn’t a bedtime medication; you’ll need to take it four hours before your desired sleep time. Any medication additions to your routine should always be first approved by your provider.

Melatonin is widely available over the counter, but not all are U.S. Food and Drug Administration (FDA)-approved. Look for brands with highly reliable amounts and low fillers. Your provider can help you choose the right one.

Always follow your provider’s instructions to take this medication safely.

How long does delayed sleep phase syndrome last?

Delayed sleep phase syndrome doesn’t go away. Treatment is ongoing to manage it. It may take several weeks to months until you’re able to reschedule your sleep-wake cycle. You’ll need to stay consistent with your treatment plan so your schedule doesn’t get thrown off course.

Is there a cure for delayed sleep phase syndrome?

There’s no cure for delayed sleep phase syndrome (DSPS). Treatment is effective at improving your sleep to reduce your symptoms.

What’s the outlook for delayed sleep phase syndrome?

Most people have a positive outlook if they’re able to follow a treatment plan to get their sleep schedule where they want it. Untreated DSPS can impact your daily life. When you’re constantly tired, it’s difficult to be active and present to do the things you enjoy. Many people who experience DSPS also have periods of depression. If you feel out of sorts due to your lack of sleep, talk to a healthcare provider. They might recommend additional treatment like participating in cognitive behavioral therapy.

When should I see a healthcare provider?

If you have trouble falling asleep at night and waking up in the morning, contact a healthcare provider. If you have a delayed sleep phase syndrome diagnosis and the changes to your sleep routine aren’t helping your symptoms, let your healthcare provider know so they can help you make adjustments to your treatment plan.

What questions should I ask my healthcare provider?

• Should I purchase a light box and how should I use it?
• How do I change my sleep routine?
• Should I take melatonin supplements and if so, what dosage and what time?
• Are there side effects of taking melatonin supplements?
• Could I have another sleep disorder like narcolepsy or OSA?

Is delayed sleep phase syndrome a part of ADHD?

Changes to your sleep cycle can affect your focus and performance during the daytime. Studies estimate that approximately 75% of people diagnosed with attention-deficit/hyperactivity disorder (ADHD) also have a condition that affects their circadian rhythm.