Disturbance of the circadian rhythm of sleep

Disorder of the circadian rhythm of sleep is a violation of the regularity of the "sleep-wake" cycle due to desynchronization of external and internal clocks. There are violations of night sleep, pathological daytime drowsiness or a combination of these, which usually go away, as the biological clock itself is reconstructed. The diagnosis is clinical. The treatment is aimed at eliminating the cause of the failure.

Disorder of the circadian rhythm of sleep can be due to external stimuli and causes (eg, biorhythm failure when moving to another time zone, shift work) or due to desynchronization of internal biological clocks with a day / night cycle (eg, late or early falling asleep syndrome).

The most common oral hypnotics

A drug	Half-life, h	Dose, mg2	Comments
Benzodiazepines
Flurazepam	40-250	15-30	High risk of residual sedation the next day; not recommended for the elderly
Kvazepam	40-250	7,5-15	Has a high lipophilicity, which can soften residual sedation in the first 7-10 days with prolonged use
Estazolam	10-24	0.5-2	Effective for induction and maintenance
Temazepam	8-22	7,5-15	The drug is characterized by the longest period of sleep induction
Triazolam	<6	0,125-0,5	May cause anterograde amnesia; high probability of addiction and addiction
Imidazopyridine
Zolpidem	2.5	5-10	Effective for induction and maintenance
Pyrazolopyrimadine
Zaleplon	1	5-20	The preparation of ultrashort action; improves sleep at the beginning of sleep or after a night awakening (at least 4 hours); reception before bedtime minimizes residual effects

¹ Including progenitors and active metabolites. ² Doses are prescribed before bedtime.

Desynchronization of sleep due to external causes also violates other circadian rhythms of the body, including hormonal secretion and temperature. In addition to insomnia and drowsiness, these changes can be accompanied by nausea, malaise, irritability and depression. The most unfavorable are repeated circadian rhythm disturbances (for example, frequent long-distance travel, rotation of shift workers). It takes a long time to restore circadian rhythms and eliminate sleep disorders. Since light is the most powerful determinant of circadian rhythm normalization, exposure to bright light (solar or artificial light of 5000-10 000 lux) after awakening helps to accelerate adaptation to new conditions. You can also use melatonin (see above).

The use of alcohol, hypnotics and stimulants to eliminate circadian rhythm disturbances is an incorrect tactic.

[1], [2], [3], [4], [5], [6], [7], [8], [9], [10]

The time zone change syndrome (biorhythm failure when moving to a different time zone)

This syndrome is caused by rapid movement through two or more time zones. A journey to the east (the transfer of sleep to an earlier time) causes a more pronounced malfunction than a move to the west (the transfer of sleep to a later time).

If possible, before a long trip, it is recommended that the sleep-wake cycle be gradually shifted to adapt it to the conditions of the place of intended stay and to maximize the effect of daylight (especially in the morning) at the new location. In addition, short-acting hypnotic drugs or stimulant drugs (for example, modafinil) can be used for a short period after arrival.

Sleep disruption with shift work

The severity of the symptoms is proportional to the frequency of shift rotations, the duration of each shift and the shift frequency of the shifts "counterclockwise" (sleep shift to earlier time). Preferably fixed shift work (ie work at night or in the evening); rotation rotation should be carried out "clockwise" (ie day - evening - night). However, even with fixed shift work, violations are noted, because daytime noise and light impair the quality of sleep, and workers often shorten the sleep time to participate in social or family events.

In shift work, it is recommended that the maximum exposure to bright light (sunlight or, for night workers, artificial light) for the waking period, as well as the creation of the most comfortable sleeping conditions (dark and quiet bedroom). You can use darkening masks on the eyes and devices to neutralize noise. With persistent sleep disorders that adversely affect daily activities, it is shown that the use of short-acting hypnotic and stimulant drugs is reasonable.

Syndromes of a disturbance of phases of a dream

With these syndromes, the normal quality and total duration of sleep in the 24-hour cycle of the circadian rhythm are preserved, but the distribution of sleep time during the day is disturbed, i.e. There are shifts in the time of falling asleep and awakening. In more rare cases, the cycle does not fit in 24 hours, i.e. Patients wake up day after day at different times, then earlier, then later, but if possible to adhere to their inherent natural cycle of sleep disorders do not develop.

For the syndrome of late sleep (delayed sleep phase) is characterized by late sleep and later awakening (for example, 3:00 and 10:00), arising from a violation of the regime, in which the time when the patient can fall asleep, comes about 3 hours later after he would like to fall asleep. This syndrome is more common in adolescence. The need for early recovery to go to work or school, is associated with increased daytime sleepiness, poor school performance and skipping morning classes. They can be distinguished from people who go to bed late, because they can not fall asleep before, even if they try. A slight delay in the time of falling asleep (less than 3 hours) is treated by a gradual earlier awakening, as well as by therapy with a bright daylight. Acceptance of melatonin before bedtime.

The syndrome of early falling asleep (early falling asleep and early awakening) is more common among the elderly. For correction, you can use therapy with bright light in the evening.