Insomnia is the second most common mental disorder, which is a major risk factor for depression. In a large-scale Dutch study, scientists sought to identify reliable subtypes of insomnia.
How common is insomnia in Russia?
In 2017, approximately every 4 adult Russians reported problems with falling asleep, the duration and quality of sleep. Some sleep disorders are so serious that they interfere with physical, mental and emotional functioning.
By 2050, due to climate change, the number of days of insomnia can almost double compared to 2017.
The overall prevalence of pathology cannot be estimated, since many do not go to the doctor.
Consequences of insomnia
42% of traffic accidents in Russia are due to drowsiness. Shift workers have a higher risk of gastrointestinal and cardiovascular disease.
Recent studies show a clear link between sleep deprivation and obesity, diabetes, high blood pressure, heart disease, stroke, and depression. Last but not least, many mental disorders are related to sleep problems.
It is known that sleep disorders temporarily impair the functioning of the immune system and endocrine organs.
Already in healthy people, significant changes in immune function are observed after short-term sleep disturbances.
It is also obvious that too short sleep leads to a decrease in sensitivity to insulin. Lack of sleep for many years leads to an increase in the prevalence of obesity. This is another factor that increases the risk of developing diabetes.
There are many studies that show a link between insomnia and immunodeficiency, obesity, and diabetes. But virtually none of these studies included many additional variables.
It has not been determined whether patients with subjective insomnia have additional sleep apnea. Comparisons between various sleep-related illnesses are rare. However, there is evidence that a disturbed sleep microstructure affects sugar sensitivity.
What types have scientists identified?
Dutch scientists studied about 4,900 volunteers who enrolled in the online sleep registry. The main conclusion of the authors of the study: insomnia is divided into 5 subtypes, which differ in the risk of developing depression and response to treatment.
For the study, experts analyzed up to 40 different questionnaires, which were filled in by about 4000 people.
Using mathematical methods of class analysis, experts identified 5 subtypes of insomnia:
- I type "severely disturbed sleep": the patient is depressed, tense and overly alarmed;
- II type "moderately disturbed sleep": the patient experiences a bad mood, but experiences positive emotions;
- III type "moderately disturbed sleep and insensitive to positive emotions": the patient is in a moderately bad mood and does not experience positive feelings during the day;
- IV type of "sleep disturbance, dependent on external factors": symptoms of insomnia depend on the environment and life circumstances;
- V type "practically not disturbed sleep": a little bad mood during the day.
After 5 years, Dutch scientists tested the new classification on other patients. They concluded that other people fit the above subtypes.
What conclusions have scientists come to?
According to the study, patients suffering from the I subtype of insomnia are at the highest risk of developing clinical depression. The lowest risk was observed in patients with subtypes IV, V, and II of insomnia.
Researchers also concluded that patients with various types of sleep disorders respond differently to medication and psychotherapy.
The first type reacted less to others than drugs, while good - to psychotherapy. And vice versa: type 4 patients responded best to medications.
Further research will help develop safer and more effective anti-insomnia drugs. Classification is currently being tested in other scientific papers.
