Delayed Sleep Phase Syndrome (DSPS) is also known as Delayed Sleep Phase Disorder (DSPD); it is a circadian rhythm (internal sleep clock) sleep disorder in which a person’s sleep pattern is delayed 2 or more hours from a ‘normal’ sleep pattern (sleep at night, wake in the morning) causing you to sleep later and wake up later. It affects the timing of sleep, the peak period of alertness, the core body temperature rhythm, as well as hormonal and other daily rhythms.
People suffering from DSPS are unable to fall asleep at a “reasonable” hour; they typically fall asleep several hours after midnight and have extreme difficulty waking up in the morning. People with this condition usually fall asleep around the same time every day and sleep well, with a normal amount of sleep, if they are allowed to follow their own schedule. However, if they are required to get up in the morning to go to school or a job they find it very difficult to wake up in time. Although such people are often called “night owls”, it is important to understand that for people with this syndrome, their hours are not by choice.
Unlike the morning and night type of people who prefer their respective times but can adjust to a normal schedule, people with DSPS do not have that flexibility and are unable to adjust to a normal schedule. If they are required to follow a normal schedule, they experience difficulty thinking clearly, driving safely and overall functioning is impaired. They often fail courses at school or lose jobs. This can affect their self esteem and confidence, leading to secondary emotional issues, clinical depression or other stress related health problems. The analogies used to describe living with DSPS liken it to living constantly with 6 hours of jet lag or trying to constantly push a boulder uphill. DSPS does tend to run in families, but in the majority of cases, there is no known cause for the abnormality in the biological clock.
DSPS is not a well known condition and it is frequently misdiagnosed or even dismissed. It is often confused with insomnia or psychiatric disorders such as schizophrenia, depression or ADHD. It has also been misdiagnosed as other sleep disorders and School Refusal.
- Complaint of insomnia or excessive sleepiness
- Inability to fall asleep at the desired time
- Inability to wake up at the desired time
- Depression may be present
- Sleep pattern has been present for at least 3 months
- Mild: two hour delay associated with little or mild impairment of social or occupational functioning
- Moderate: three hour delay associated with moderate impairment
- Severe: four hour delay associated with severe impairment
People who have DSPS most typically cannot fall asleep until after 2 a.m. with some reporting not being able to sleep until 6 or 7 a.m. It does not matter how early they got up the morning before or how tired they are, they cannot sleep until early morning. They are often baffled as to why they cannot find a way to fall asleep more quickly. Many have tried having a friend or family member wake them in the morning, relaxation techniques, going to bed early, or using sleeping pills but none of these efforts work permanently. As for sleeping pills, there are reports that normal doses have little or no effect in helping them fall asleep and only aggravate the symptoms of daytime sleepiness and difficulty waking up. Some people with this condition manage to function on a few hours sleep per night during the work week and then try to catch up on sleep on the weekend by sleeping excessively. Following this schedule often leads to unclear thinking and poorer performance.
Depression: Depression or other psychiatric problems are present in about 50% of the adults with DSPS. This is about the same percentage for people suffering from other forms of insomnia.
Body Temperature: Body temperature fluctuates on a daily (circadian) cycle, rising during the day until it peaks in the evening, and then falls at night. The overall range is typically 1 to 2 degrees Fahrenheit. For most people with DSPS, this typical pattern of temperature fluctuation is shifted as well.
Related sleep disorders: Some people have other sleep disorders in addition to DSPS which compounds their problems. If they have sleep apnea, this will interfere with getting good rest even during their natural sleep time. Still others have reported restless leg syndrome as well as other causes of poor quality sleep. People with these related sleep difficulties usually require more than 8 hours of sleep in addition to a shifted schedule.
DSPS comprises about .15% of the adult population, or 3 out of every 2,000 people. It is equally distributed among men and women in the adult population but it is male dominated during adolescence. DSPS is more common among teenagers with an estimation of about 7%.
The syndrome usually begins in early childhood or adolescence. Adolescence appears to be the most common time, a vulnerable period of life, for the development of DSPS. However, childhood cases are documented. It is rare for it to develop after the age of 30.
Although there are some cases where DSPS disappears after adolescence, for many it is a lifelong condition. Symptoms can be managed, to a greater or lesser degree, but there is no permanent cure. There are a number of typical treatments (most common are listed below) and they are often used together. The treatments are reported to be effective with some patients while others show no improvement. For the latter, they must adjust their social and work times to accommodate their delayed sleep schedule or the fore mentioned mental and physical dysfunction will likely prevail.
Good Sleep Hygiene
People with DSPS must improve their ‘sleep hygiene’ by having a comfortable bedroom that is used only for sleeping, no TV or computer. It should be dark and quiet. They must go to bed at the same time every night, seven days a week, in order for their body to establish a regular schedule. Other rules to follow:
- No napping during the day
- Avoid alcohol
- Avoid caffeine 6 hours before bedtime
- No serious exercise 3 hours before bedtime
- Avoid tobacco
- Avoid stimulating activities near bedtime; try to relax just before bedtime
The most successful treatment, so far, has been providing bright light in the morning. Having light exposure in the morning may adjust the circadian rhythm. This is done by either going out in the sunlight or using a bright light made for this purpose (they can be found on the internet by searching for lights to treat Seasonal affective Disorder).
Chronotherapy is a behavioral technique in which bedtime is systematically delayed by 2 to 3 hours every day or two until the desired bedtime is reached. Since it is known that DSPS people can’t shift their sleep time earlier, this schedule shifts their sleep time later instead. The most difficult part of this treatment is sticking rigidly to the newly established schedule seven days a week with no nights off to study, socialize or stay up with a sick child. Even one night with a delayed bedtime is likely to make their body clock shift later again. Most people find such a rigid schedule impossible to always follow and hence, the Chronotherapy fails.
Melatonin supplements have been prescribed by physicians to take in the afternoon or early evening to help adjust the circadian rhythm. Melatonin occurs naturally in the brain and the concentration is higher during the hours of sleep, with less during the hours of wakefulness. Typically, melatonin is taken 30 minutes to 2 hours ahead of bedtime. However, with DSPS patients it was shown that the optimal time was 6 to 8 hours before bedtime.
*Note: melatonin is believed to help shift circadian rhythms; this is not true of other sleeping pills.