CHRONOBIOLOGICAL ASPECTS OF ANXIETY DISORDERS AND DISSOMNIC DISORDERS AND THEIR PREVALENCE IN THE CONTEXT OF THE COVID-19 PANDEMIC

In a situation of rapidly changing environmental conditions and the growth of stress of different strengths and orientations, people are more likely to experience anxiety. The results of epidemiological studies show that up to 33.7% of the population suffers from lifelong anxiety disorders. According to large population-based surveys, comorbidity among people with this pathology is high: three out of four people with anxiety disorder experience at least one other mental disorder during their lifetime. The pathogenetic mechanisms of anxiety and insomnia are closely related, mutually aggravating each other’s influence. The difficulty of sleep generation and regulation makes this process very vulnerable to sleep and circadian rhythms disturbances, which include problems with the quality, time and quantity of sleep. Some researchers suggest that anxiety acts as an endogenous factor that affects the manifestations of the sleep-wake cycle, and the irregularity of this cycle contributes to anxiety. Recent studies display that chronotype may also be an important occurrence marker of chronic primary insomnia and a risk factor for anxiety disorders.The COVID-19 pandemic has become a major challenge for the mental health of people around the world. Numerous scientific publications have covered the prevalence of mental and behavioural disorders, including anxiety and dyssomnia, both in the context of psychosocial stress caused by the COVID-19 pandemic and in patients with long-term consequences after coronavirus disease. The term “Long COVID” covers a number of features that indicate damage to many organs, and lasts for weeks and months after the onset of the disease. An analysis of the literature shows that although physical symptoms are given the most attention, the impact of COVID-19 on mental health is no less important. At present, the long-term COVID-19 syndrome has not been definitively identified, but the leading signs of mental disorders after coronavirus disease, including sleep problems, anxiety, depression, fatigue, and cognitive difficulties, have been described.