Chronotherapy (sleep phase)

Example

Here is an example of how chronotherapy could work over a week's course of treatment, with the patient going to sleep 3 hours later every day until the desired sleep and wake time is reached.

• Day 1: sleep 3:00 am to 11:00 am
• Day 2: sleep 6:00 am to 2:00 pm
• Day 3: sleep 9:00 am to 5:00 pm
• Day 4: sleep 12:00 pm to 8:00 pm
• Day 5: sleep 3:00 pm to 11:00 pm
• Day 6: sleep 6:00 pm to 2:00 am next day
• Day 7: sleep 9:00 pm to 5:00 am next day
• Day 8 and thereafter: sleep 12:00 am to 8:00 am next day

While this technique can provide respite from sleep deprivation for people who must wake early for school or work, the new sleep and wake times can only be maintained by following a strictly disciplined timetable for sleeping and rising.

Other forms of sleep phase chronotherapy

A modified chronotherapy is called controlled sleep deprivation with phase advance, SDPA. One stays awake one whole night and day, then goes to bed 90 minutes earlier than usual and maintains the new bedtime for a week. This process is repeated weekly until the desired bedtime is reached.

Sometimes, although extremely infrequently, "reverse" chronotherapy – i.e., gradual movements of bedtime and rising time earlier each day – has been used in treatment of patients with abnormally short circadian rhythms, in an attempt to move their bedtimes to later times of the day. Because circadian rhythms substantially shorter than 24 hours are extremely rare, this type of chronotherapy has remained largely experimental.

Side effects

The safety of chronotherapy is not fully known. While chronotherapy has been successful for some, it is necessary to rigidly maintain the desired sleep/wake cycle thenceforth. Any deviation in schedule tends to allow the body clock to shift later again.

Chronotherapy has been known to cause non-24-hour sleep–wake disorder in at least three recorded cases, as reported in the New England Journal of Medicine in 1992. Animal studies have suggested that such lengthening could "slow the intrinsic rhythm of the body clock to such an extent that the normal 24-hour day no longer lies within its range of entrainment."

References

References

1. "Behavioral Treatment of Circadian Rhythm Disorder".
2. Dawn Dore-Stites, PhD. (2017-04-21). "Delayed Sleep Wake Phase Disorder in Adolescents: Chronotherapy and Best Practices".
3. (2015). "Clinical Practice Guideline for the Treatment of Intrinsic Circadian Rhythm Sleep-Wake Disorders: Advanced Sleep-Wake Phase Disorder (ASWPD), Delayed Sleep-Wake Phase Disorder (DSWPD), Non-24-Hour Sleep-Wake Rhythm Disorder (N24SWD), and Irregular Sleep-Wake Rhythm Disorder (ISWRD). An Update for 2015". Journal of Clinical Sleep Medicine.
4. Thorpy et al. in J Adolesc Health Care, 1988;9.
5. Morgenthaler, TI. (November 2007). "Standards of Practice Committee of the AASM. Practice Parameters for the Clinical Evaluation and Treatment of Circadian Rhythm Sleep Disorders". Associated Professional Sleep Societies, LLC.
6. Oren, Dan A.. (10 December 1992). "Hypernyctohemeral Syndrome after Chronotherapy for Delayed Sleep Phase Syndrome". Massachusetts Medical Society.