Main Symptoms of DSPS

DSPS causes sleep-onset insomnia. Often, DSP individuals report that they cannot sleep until early morning. Unlike most other insomniacs, however, they fall asleep at about the same time every night, no matter what time they go to bed.

Unless they have another untreated sleep disorder (such as sleep apnea) in addition to DSPS, patients can sleep well, and have a normal need for sleep. Therefore, they find it very difficult to wake up in the morning if they have only slept for a few hours. However, they sleep soundly, wake up spontaneously, and do not feel sleepy again until their next "night," if they are allowed to follow their own late schedule, e.g. sleeping from 4 am to noon.

Symptoms have been present for at least a month, and usually much longer.

In addition to the main symptoms of DSPS, most people with DSPS also have some or all of the following features:

DSP individuals are night owls. They feel most alert and say they function best, are most creative, etc. in the evening and at night.
They usually have tried many times to change their sleeping schedule. Failed tactics to sleep at earlier times may include relaxation techniques, early bedtimes, hypnosis, alcohol, sleeping pills, dull reading, and folk remedies. They often have asked family members to help wake them in the morning, or they have used several alarm clocks. Or family members - especially parents - have tried to get them up on time.
Symptoms often begin in adolescence, childhood, or infancy.
They are sleepy during the day, especially in the morning, if they have had to get up early. They sleep in on weekends (often past noon and for more than 10 hours) to make up for not getting enough sleep during the rest of the week. Some people with DSPS take naps during the day and feel refreshed afterwards.
Many people with DSPS need at least 30 minutes to fall asleep, even when they go to bed at a time that is realistic for them.
Some people with DSPS have occasional, sudden, and temporary reversions to sleeping at earlier times.

What Causes DSPS?

DSPS is believed to be a disorder of the body's timing system - the biological clock. DSP patients have fifficulty falling asleep and difficulty waking because their biological clocks are out of phase with the sleeping and waking times they try to carry out. DSPS is similar to jet lag, but much longer-lasting. It can develop suddenly or gradually.

You probably have heard of a biological clock which governs growth, reproductive cycles, and aging. There are also bodily rhythms, known as circadian rhythms, which are also controlled by a biological clock and which work on a daily time scale. You might have already noticed, in yourself or in others, that sleepiness doesn't just keep increasing as it gets later. Rather, the drive for sleep follows a cycle, and the body is ready for sleep and for wakefulness at different times of the day.

DSPS doesn't bother everyone who has it. Some people are happy and healthy with a late sleeping schedule, and have found ways to adjust their lifestyle to it. For this reason, many researchers consider DSPS to be a "disorder" only when it interferes with the individual's work or social functioning.

Keeping a Sleep Log

If you think you might have DSPS and consider it a problem, take down the list of symptoms shown above, and discuss them with someone who knows you very well, preferably someone who has lived with you. You should also start to keep a sleep log so a doctor can evaluate your symptoms. This takes a few minutes every day. You should write down:

Time you tried to fall asleep
Time you think you fell asleep
Any nighttime awakenings
Time you woke up
Time you got out of bed
Time you had to be up
Whether you got up by yourself, by an alarm clock, or because you were disturbed
A few words about how you felt during the day
Any daytime naps - how long and when

What Medications You Used

It is easier to distinguish DSPS from other causes of inadequate sleep if the sleep log is recorded when the patient is not taking sleeping pills, sedatives of any kind, or stimulants such as caffeine. But if your doctor has already recommended one of these types of medication for you, continue to take it as directed until your doctor agrees it is safe for you to stop.

Finding a Sleep Specialist

You may have to look hard to find a physician who can recognize and treat DSPS. Try calling your local sleep disorders clinic, or the departments of psychiatry, neurology, and internal medicine at your local hospital. Ask, "Do you treat sleep disorders?" then, "Can you treat circadian rhythm sleep disorders, such as delayed sleep phases syndrome?" Don¹t be discouraged if they cannot help you. Keep looking. The Talk About Sleep Directory includes a list of sleep disorder clinics and national sleep medicine associations. You can also write to your local sleep medicine association and ask about accredited sleep clinics in your area.

At least two weeks of sleep logs are needed to diagnose DSPS. Many sleep clinics encourage new patients to bring a family member, roommate, or friend to the first visit. An overnight stay in a sleep lab is usually not necessary, except to rule out other sleep disorders.