Definition and clinical presentation
The normal duration of night sleep is 7–8 hours, with a sequential alternation of cycles throughout the night. One cycle lasts on average 1.5–2 hours and consists of stages of slow-wave sleep, ending with a rapid eye movement (REM) sleep episode.
Insomnia is a condition in which the sleep process is disrupted despite a comfortable environment and sufficient time for it. Patients present with typical complaints:
- Difficulty falling asleep.
- Fragmented sleep and frequent nighttime awakenings.
- Too early morning awakening.
- A persistent feeling of unrefreshed sleep.
These nocturnal symptoms inevitably entail daytime manifestations. The person suffers from increased fatigue, irritability, and impaired concentration. Combined, this leads to a noticeable impairment of the patient's social and daily adaptation.
Classification of insomnia
In clinical practice, sleep disorders are generally classified by their duration:
- Transient insomnia — symptoms bother the patient for less than one week.
- Acute insomnia — disorders persist for up to one month.
- Chronic insomnia — lasts for more than one month.
From an etiological standpoint, two major groups are distinguished:
- Exogenous form, triggered by external triggers: stressful situations, alcohol or drug abuse, or simple poor sleep hygiene.
- Endogenous form, including primary (idiopathic) and psychophysiological insomnia. This same group includes secondary sleep disorders arising against the background of restless legs syndrome, obstructive sleep apnea, and various somatic, psychiatric, and neurological pathologies. Circadian rhythm disruptions and the consequences of shift work also fall into this category.
Non-pharmacological management
The basis of therapy is the elimination of the cause of the disorder and adherence to sleep hygiene. This is a critically important stage, without which pharmacological intervention often fails to provide a lasting effect. Treatment principles always assign a primary role to non-pharmacological methods.
Sleep hygiene rules:
- Getting up in the morning strictly at the same time every day.
- Elimination or strict restriction of daytime naps (especially in the second half of the day).
- Reduction of mental and physical activity towards evening (regular workouts should be finished at least 2 hours before bedtime).
- Avoiding overeating, strong tea, and coffee in the evening hours.
- Using relaxing water procedures before bedtime.
Behavioral therapy requires that the bed be used only for sleep. One should go to bed exclusively when feeling sleepy.
Pharmacotherapy
Pharmacological support aims at the symptomatic improvement of nighttime rest quality. Dosage is always selected individually.
- Z-drugs (non-benzodiazepine hypnotics): zopiclone, zolpidem, zaleplon. They are drugs of choice as they have a narrower spectrum of adverse effects.
- Benzodiazepine tranquilizers: diazepam, phenazepam, lorazepam, clonazepam. Effective for sleep-onset difficulties and frequent awakenings.
Important limitation: both of these drug groups are prescribed in a short course — strictly no more than 3–4 weeks to avoid the risk of tolerance, dependence development, and daytime side effects.
Additional agents:
- For mild forms: antihistamines (diphenhydramine, doxylamine) and herbal sedatives (valerian root, motherwort herb).
- Melatonin: a synthetic analog of the pineal gland hormone. Optimal for elderly and senile patients, as well as for circadian rhythm disorders.
Briefly: answers to topical questions
Which specific somatic and neurological diseases most frequently cause secondary endogenous insomnia?
The sources explicitly indicate the following causes of secondary endogenous insomnia:
- obstructive sleep apnea;
- restless legs syndrome;
- other neurological, psychiatric, and somatic diseases, the specific list of which is not provided in the source.
What cognitive behavioral therapy (CBT-I) methods are used to treat chronic insomnia?
The sources describe the following behavioral therapy methods:
- going to bed exclusively when experiencing sleepiness;
- if sleep does not occur within 20–30 minutes, getting out of bed;
- engaging in a calm activity without emotional tension, such as reading or listening to music;
- returning to bed only when the desire to sleep appears.
Which antidepressants with sedative effects are used for the pharmacotherapy of chronic insomnia?
When depression and insomnia coexist in patients with Parkinson's disease, antidepressants with sedative effects are used:
- trazodone — 50–150 mg/day;
- mirtazapine — 7.5–30 mg/day;
- agomelatine — 25–50 mg.
What stages are distinguished in the structure of the slow-wave phase of the physiological sleep cycle?
In the structure of the slow-wave sleep phase (non-REM sleep phase), three main stages are distinguished:
- Stage I — a state of drowsiness and superficial sleep, accompanied by the disappearance of the α-rhythm and the appearance of low-amplitude β- and θ-rhythms.
- Stage II — medium-depth sleep, characterized on the electroencephalogram by the appearance of "sleep spindles".
- Stage III — the deepest delta sleep, during which a high-amplitude delta rhythm is recorded (previously this phase was divided into stage III and stage IV).
The 30-minute rule: if a patient cannot fall asleep within 20–30 minutes, they should get out of bed, engage in a relaxing activity, and return only when feeling sleepy.
Class and exam questions
What is the difference between acute and chronic insomnia?
Acute insomnia is diagnosed if symptoms last for up to one month. If sleep disturbances persist for more than a month, the condition becomes chronic.
Why are tranquilizers and Z-drugs prescribed only for a short course?
Their use is strictly limited to 3–4 weeks to prevent the development of drug dependence and addiction, as well as to avoid pronounced daytime side effects.
In which cases is the prescription of melatonin most justified?
The drug is the agent of choice for managing insomnia in elderly or senile patients, as well as in cases of marked circadian rhythm disorders.
What else to study on this topic
- Polysomnographic pattern of slow-wave sleep stages (sleep spindles, delta rhythm).
- Specific EEG, EOG, and EMG changes during the rapid eye movement (REM) sleep phase.
- Multiple Sleep Latency Test (MSLT) and differential diagnosis of daytime sleepiness.
- Secondary forms of insomnia associated with sleep apnea and restless legs syndrome.
- Hypersomnias: etiology and classification of primary and secondary forms.
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