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Daytime sleepiness: is there any reason for concern?
Last reviewed: 23.04.2024
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If a person is not chronically sleepy, that is, the duration of a night's sleep is less than seven hours a day, and this lasts from day to day for a month or more, daytime drowsiness is a logical consequence of a violation of the physiological norm of night rest of the central nervous system and the whole organism.
But it is often difficult to overcome the desire to sleep in the daytime, especially after noon, occurs in those who sleep at night enough. What is the reason for this?
Causes of daytime sleepiness
So, the simplest reason for daytime drowsiness is a constant lack of sleep, and obviously there are no questions with it. Although, as is known, the physiologically determined individual need for sleep may not coincide with generally accepted standards and be less than or more than seven to eight hours. As a rule, this is due to the specificity of anabolism - when for the biochemical processes of synthesis of substances occurring at night and restoration of immunity (due to the production of T-lymphocytes) a little more time is needed.
This also includes a disturbance of the circadian rhythm of sleep, that is, a shift in the periods of wakefulness and sleep relative to the time of day, for example, in shift work, and also in the case of a sudden change in the time zone (jitlag syndrome).
In modern somnology (a field of medicine that explores the physiology and pathology of sleep), the following causes of daytime drowsiness are considered:
- insomnia (insomnia), the development of which can be due to neurotic states, stress, mental disorders, etc .;
- pathology of the brain (tumors, hematomas, cysts, hydrocephalus) and craniocerebral trauma;
- sleep apnea syndrome (impaired respiratory function in sleep state of a mechanical or psychogenic nature);
- hypersomnia (psychophysiological, narcoleptic, iatrogenic, idiopathic);
- prolonged latent leaking depression;
- endocrine diseases (diabetes mellitus type II, hypothyroidism);
- lack of iron in the blood ( iron deficiency anemia ).
Daytime sleepiness is a dangerous symptom of sleep apnea ("breathlessness"), during which a short-term (for 15-25 seconds) a sudden stop of breathing due to the cessation of contractions of the respiratory muscles. This breaks the normal structure of sleep: a person either wakes up, or his sleep becomes superficial. And when apnea is caused by the narrowing of the airway lumen in a dream, the diagnosis sounds like obstructive sleep apnea syndrome. On this basis, some men with severe obesity after forty years can not take deep breaths and accelerate the rate of respiration, which gives grounds to diagnose in them a pathology such as alveolar hypoventilation of the lungs (the so-called Pickwick's syndrome), which is characterized by increased daytime sleepiness.
Speaking of hypersomnia, experts mean excessive sleep duration at night, as well as peculiar bouts of daytime sleepiness. First and foremost, here include narcolepsy (Gelino's disease), in which there is a restless, often interrupted night's sleep and short-term confusion in the sleepy state during the day - sometimes in the most unexpected situations, for example, when traveling. In such cases, neurologists diagnose cataplexy - a muscle weakness for a few seconds (a kind of stupor) without losing consciousness. The development of narcolepsy is associated with the genetically determined deficiency of the oryxine neuropeptide (hypocretin), which is synthesized by the hypothalamus and provides transmission of stimulating nerve impulses.
Non-insulin-dependent diabetes mellitus was included in the list of causes of daytime drowsiness due to disorders in the provision of glucose cells to the body, resulting from insensitivity to insulin. It is also known that in this disease the epiphysis (pineal gland of the intermediate brain) produces less melatonin, a neurohormone that regulates the circadian rhythms of the body and is synthesized only at night. So any changes in its development lead to sleep disorders in the form of insomnia or increased sleepiness during the daytime.
In congenital or acquired hypothyroidism (insufficient thyroid hormones) - in addition to weakness, rapid physical fatigue, headaches, coldness, dryness of the skin - the person also suffers from excessive daytime sleepiness. Almost the same symptomatology takes place with iron deficiency anemia.
Finally, drowsiness can be a side effect of anti-edematous, antihypertensive, anti-asthmatic or steroid drugs.
How to deal with daytime sleepiness?
Among the recommendations, how to deal with daytime drowsiness, in the first place are drinks containing caffeine. Caffeine has psychostimulating properties that promote the activation of all body functions, including vascular tone and the synthesis of neurohormones. But doctors knowingly warn of the harm of coffee abuse and strong tea (in particular, towards evening), since excess caffeine can cause psychogenic dependence - theism, which is accompanied by headaches, nervousness, increased heart rate and, of course, insomnia. So after 16-17 hours, drinking coffee is undesirable.
Morning exercise, a warm shower (or at least washing to the waist) and breakfast are three whales, on which stands a cheerful state throughout the whole working day. The temperature of water can be gradually reduced to + 28-30 ° C and make contrasting water procedures.
For breakfast, it is useful to eat cereals, that is, cereals, vegetable salads with boiled meat or fish, as well as eggs and cottage cheese with sour cream.
Prevention of daytime sleepiness - the proper preparation for a night's sleep or sleep hygiene. According to the recommendations of the specialists of the American National Sleep Foundation (NSF), it is necessary to adhere to healthy habits, namely:
- to refuse from late (after 19 hours) meal;
- try to go to bed and wake up at the same time (even on weekends);
- every night take a soothing shower (with a water temperature of not more than + 40 ° C).
- in the evening not to include in the apartment too bright light and too loud music;
- When sleeping with sleep, sleep should be avoided;
- daily exercise;
- in the bedroom should be quiet, fresh and comfortable;
- quiet classes before bedtime exclude the use of electronic devices (for example, a laptop), since a certain type of light emitted from the screens of these devices activates the brain.
It is clear that the forecast of daytime sleepiness entirely depends on its cause. Thus, in the syndrome of obstructive sleep apnea, cerebral hypoxia and heart failure often occur, up to cardiac ischemia. Although any daytime drowsiness - regardless of etiology - negatively affects the general condition and performance of a person.
Diagnosis of daytime sleepiness
Diagnosis of daytime sleepiness is aimed at finding out the causes of this condition. Sometimes a doctor suffers from the usual listening to the patient's complaints and clarifying his daily routine and living conditions, as well as asking about his illnesses, injuries, stresses and medications used.
However, in order to diagnose this, it is not enough, and then a neurologist or somnologist conducts special testing to find out the optimal duration of a night's sleep, which provides the patient with a sense of cheerfulness after awakening.
In addition, the study of key neurophysiological indicators of sleep using polysomnography, and the characteristics of the functioning of individual brain structures are clarified during EEG (electroencephalography).
Since daytime sleepiness often causes suspicion of sleep apnea, it may be advisable to carry out respiratory or cardiorespiratory monitoring (studying the rhythm of breathing during the night sleep), as well as finding out the level of oxygen in the blood by pulse oximetry.
Naturally, in the presence of diseases of any organs and systems, primarily endocrine, which may be involved in daytime drowsiness, it is necessary to undergo a complete examination with specialists of the appropriate profile, including the delivery of blood and urine tests.