Kristin was late to school again, as she had been so many times before. Since she didn't go to bed until 3:00 a.m., she wasn't able to get out of bed at 6:30 a.m. for school. This time she had to meet with the principal. The message was clear: take care of this problem or you will fail and not graduate with your class. After discussing this problem with her parents, she agreed to see her pediatrician who recommended an evaluation with a behavioral sleep specialist. The diagnosis was clear. Kristin has delayed sleep phase disorder. A letter was sent to the principal asking for a temporary later start time for school while she was working on her sleep problem. This request was granted by giving her a study hall in the morning with prior approval to miss this class if necessary. This reduced her stress considerably and helped her better focus on her school work and on the sleep program.
The sleep specialist recommended immediately limiting use of the computer and sending text messages to friends to no later than 9 p.m. Not wanting to fail this school year, she reluctantly agreed. Her parents obtained a recommended bright light box that she would start using every morning upon awakening. She started taking an over the counter supplement of melatonin, although the sleep specialist noted that this is not an FDA approved treatment and over the counter supplements are not closely regulated by the government. She also kept a sleep journal, started going to bed 15 minutes earlier every few days and used a very loud alarm to get out of bed in the morning. Although it was difficult, over a period of a number weeks she was able to "reset" her circadian clock. She eventually was going to bed around 11:00 p.m. and was able to get herself up at 6:30 a.m. She still tended to sleep a bit later on the weekends but maintained a regular 11 p.m. bed time most nights of the week, including weekends. This took some ongoing effort on her part. She almost never missed her morning study hall. She finished the school year with reasonable grades and graduated with her class.
Kristin's treatment highlights a number of the techniques used to "reset" the circadian clock and end the nightmare of delayed sleep phase disorder. The techniques are described in greater detail below.
Some of these techniques, such as keeping a sleep journal, gradually going to bed earlier and not looking into bright light sources like computers late at night can be used by any one who finds that they are going to bed and getting up later and later. Other techniques such as phototherapy, oral melatonin and chronotherapy should be used under the direction of a sleep specialist or a physician familiar with these techniques. This is because careful attention must be paid to the timing of these interventions so as to not make sleep problems worse. Calculating the appropriate times requires sound knowledge of the sleep/wake cycle and circadian rhythms. In addition, phototherapy must be used with extreme caution by anyone with a history of bipolar disorder as use of the light source at an inappropriate time could contribute to the onset of a manic episode.
Delayed sleep phase disorder occurs when there is a delay in the major sleep episode relative to the desired clock time. As a result, the person has a hard time falling asleep and getting up at a normal time. Often people with this problem will use sleeping pills or alcohol to try and get to sleep sooner but this rarely works. Alcohol usually makes the problem worse. It is still unclear to what degree both genetic and environmental factors impact on the development of this disorder but both are most likely involved. People with this disorder may experience depressed mood and have great difficulty functioning at school or work. A delayed sleep phase occurs when people are habitually going to bed later and getting up later than the desired clock time. (An advanced sleep phase, often seen in the elderly, is the opposite. The bed time and rise times occur earlier in the day than is normative.) People with delayed sleep phase disorder typically go to sleep between 2:00 and 6:00 a.m. Delayed sleep phase disorder may last from months to decades, usually starts in adolescence and rarely starts after age 30. A typical goal for treatment would be to have a sleep schedule with a sleep period of 11 p.m. to 7 a.m.
Sleeping medication is sometimes used temporarily in an effort to induce sleep at a normal time. This often is not very successful and usually results in daytime grogginess. It is most helpful to people who also have some degree of insomnia.
Morning Phototherapy involves exposure to bright light upon awakening. It helps to increase morning alertness and advances the sleep phase in the evening. An inexpensive way to get exposure to bright light (depending on weather conditions, the location and season of the year) is to open the window shades or take a walk in the bright morning sun. Alternatively a specially designed bright light box may be prescribed. These boxes provide between 2,500 and 10,000 lux. Depending on the brightness level, they are used for periods of 30 min to 2 hours. Precise timing of use is critical and is related to the core body temperature minimum. The light is administered about 30 minutes earlier every other day to help gradually advance evening sleep onset. This treatment can be effective in 2 to 3 weeks when combined with evening light avoidance, but often requires ongoing treatment to maintain gains.
Evening light avoidance involves greatly reducing room lighting and light exposure in the evening. This is necessary to prevent worsening of delayed sleep onset. It may even be necessary to use protective eyewear, such as sun glasses, in the evening when driving home from work to reduce light exposure.
Ingestion of oral melatonin later in the day has the effect of advancing the onset of sleep. Proper timing is again critical and is dependent on the dim light melatonin onset which occurs about 14 hours following the habitual wake time. A reasonable estimate for the appropriate time to take melatonin for the purpose of advancing sleep onset is about 8 hours after the natural wake up time. A lower dose is recommended in order to get the clock resetting effect without creating strong drowsiness as may occur with higher doses.
Chronotherapy can be used if there is a flexible enough daytime schedule. Sleep onset is delayed 2 - 3 hours on successive days until the desired bed time is reached. Obviously, this will be difficult for anyone with a regular work or school schedule. It may be possible to do over a vacation. Once a regular bedtime is established it must be rigorously maintained. Relapse is possible and the process may need to be repeated.
Cognitive behavior therapy is useful to help people improve their sleep hygiene such as keeping a better sleep schedule, decreasing excessive caffeine use and adhering to evening light avoidance. People with delayed sleep phase may also have conditioned arousal that contributes to concomitant insomnia that may be usefully addressed by cognitive behavior therapy.
Maintenance is extremely important. Keeping a regular bedtime and morning rise time as well as continuing to have morning light exposure and avoiding evening light are critical to maintaining the hard won gains of therapy.