Insomnia is a significant factor in cognitive impairment: Literature review and clinical observation

The work presents an analysis of the current literature on the effect of insomnia on cognitive functions. The search was carried out using the databases of RSCI, Russian Medicine, Embase, Medline, Scopus, Web of Science, Google Scholar, using the keywords: insomnia, sleep disorder, cognitive functions, memory, functional MRI, treatment of insomnia, doxylamine. The search depth was 40 years. The consequences of sleep disorders include effects on chromosome telomeres, decreased neuron activation, and impaired brain connectivity. Insufficient sleep alters the activity of cortical neurons in areas responsible for cognitive functions, disrupts the functional connection between brain regions mediating executive functions, memory, and emotion regulation. Glymphatic clearance plays an important role in the pathogenesis of Alzheimer’s disease, as the vast majority of toxic metabolites are eliminated during sleep, and dementia is associated with sleep disorders along with age-related decreased aquaporin-4 function. The accumulation of toxic metabolites (including amyloid-β) begins at a young age and is associated with a shortening of sleep duration. Non-drug sleep improvement measures include behavioral correction: learning sleep habits, optimizing sleep conditions and improving sleep patterns, moderate physical activity during the day, and correcting environmental factors. In case of insomnia, central histamine H1 receptor blockers may be prescribed. Doxylamine is a drug used to treat nausea and vomiting in pregnant women, allergic rhinitis, and insomnia. Valocordin®-Doxylamine is a safe and effective over-the-counter medication that can benefit the patient with minimal side effects if used correctly.