The biological processes by which animals and plants regulate their "internal clock" (approximately a 24-hour day) are called circadian rhythms.
Circadian rhythm disorder refers to a disruption of a person's day-night rhythm, where the patient's sleep cycle differs from that of a normal person, resulting in an inappropriate rhythm.
For these patients, even without other types of sleep disorders, it often causes difficulties in their daily life, social life, or work.
Factors that can cause circadian rhythm disorders include: shift work, pregnancy, changes in time zones, medications, lifestyle habits, age, and diseases.
Clinically, sleep rhythm disorders can be divided into four main categories: delayed, early, irregular, and non-24-hour.
Rhythm therapy
Patients must first use an activity watch and a sleep log to record their daily sleep patterns. Then, a professional sleep manager will use a gradual approach to adjust their sleep-wake rhythm. The entire treatment may take 2 to 4 weeks to achieve the desired goals.
Drug treatment
The most commonly used medication for treating sleep rhythm disorders is melatonin, a naturally occurring neurohormone that promotes nighttime biological signals and related sleep behaviors and responses. Melatonin levels may gradually decrease or become irregular due to age or irregular sleep patterns, sometimes requiring oral administration.
Phototherapy
Light therapy uses light to transmit messages through the retina to the nerve nuclei in the hypothalamus of the brain, triggering a chain reaction that balances melatonin secretion, thereby adjusting the biological clock and improving sleep rhythm. Different light exposure times can be applied depending on the desired rhythm adjustment. Generally, morning light therapy can advance bedtime, while evening light therapy can delay it. Light therapy may also improve difficulty falling asleep, prolong sleep duration, and increase sleep efficiency. Because ultraviolet light is filtered out, light therapy is quite safe and does not cause side effects such as sunburn, cataracts, or skin cancer.