Delayed sleep-phase syndrome (DSPS), also known by the term delayed sleep-phase disorder (DSPD), is a sleep disorder where the timing of the sleep, time when an individual is most alert, body temperature system are affected when it is compared to the normal population People who suffer from this disorder typically sleep after midnight and find it very difficult to get up early in the morning. The main characteristic of this disorder is the mismatch between the sleep pattern that the affected person has and the sleep pattern that is followed commonly in the society. In other words, people with this disorder are not able to sleep when they are expected to sleep.
Physiology of Delayed Sleep Phase Syndrome (DSPS or DSPD)
The delayed sleep phase syndrome is a disorder of the time system of the body. Normally, people who have been sleep deprived the night before fall asleep quickly the next day but in case of individuals affected with DSPS they are not able to sleep before their stipulated time irrespective of whether they got adequate sleep the previous night or not. In other words, people with Delayed Sleep Phase Syndrome fall asleep only at a particular time, which is usually after midnight and have great difficulty in getting up in the morning hours. In most of the patients with DSPS the cause of it is unknown but some studies have shown that there is a genetic link to it. There are some cases where DSPS has developed due to a trauma to the head.
Diagnosis for Delayed Sleep Phase Syndrome (DSPS or DSPD)
To diagnose DSPS, the physician conducts a clinical interview and also conducts a test called as Actigraphy, which is study of activity and rest cycles of an individual. It can also be diagnosed by maintaining a sleep log of up to at least four weeks duration. Polysomnogram can also be done to rule out other causes of lack of sleep like sleep apnea or other conditions. This syndrome is generally misjudged to be a psychiatric condition and dismissed.
Treatment for Delayed Sleep Phase Syndrome (DSPS or DSPD)
The Following Treatments Are Generally Used:
- Nonmedicinal Approach: In this approach, phototherapy with either the use of a spectrum lamp or natural sunlight is used for treatment. This is continued for a few weeks. The success of this treatment is generally different from individual to individual. Trying to obtain an early sleep onset with sleeping in a dark room and keeping the eyes closed may also help.
- Pharmacologic Approach: A medication called melatonin is generally used to induce sleep, generally taken before bedtime. Another drug that is used is called Provigil which is also helpful as it allows an individual to perform normally during regular hours even though that person may be sleep deprived. Trazodone has also been used for treatment of this syndrome.
- Apart from all the therapies and the medications that can be used, a strict sleep schedule and a good sleep hygiene is enough for a person to get rid of this syndrome. Intake of caffeine and other stimulants should be avoided in the evening hours.
Prognosis of Delayed Sleep Phase Syndrome (DSPS or DSPD)
Long term success has still not been established as of now. If a person suffering from DSPS elects to work in the night shift then the affects of this disorder is minimized Some industries which can be useful for people suffering DSPS are the Information technology Industry, Call centers, Hospitality Industry such as restaurants or bars, driving, working in the media, etc.
In the United States, there is an act called as "Americans with Disabilities Act" which requires the employers to make accommodations for people suffering from sleep disorders employers which in this case will be giving a person work which can be done after the usual 9 a.m. to 5 p.m. schedule.