Anxiety disorders in clinical practice: from development mechanisms to differentiated therapy

Abstract

Affective disorders represent an extremely topical issue in modern healthcare. Prevalence of anxiety disorders in clinical practice increased significantly since 2019 due to various situational causes, and the trend will probably continue in the coming years. Besides, due to aging of the population and significant growth of the number of patients with neurodegenerative diseases, so called secondary affective disorders also increase. These are linked to organic lesion of the zones strategically important for emotional process implementation, and damaging of the key neurotransmitter systems neurons often seen in neurodegenerative pathological process. Development of anxiety is chiefly based on the defect of the “threat-fear” bound, with the reaction developing in the organism not equivalent to the degree of danger. On pathophysiological level this can be explained by disruption of interaction between limbic system structures that provide “fight or flight” reflex response to the threat, and the neocortex responsible for cognitive processing and adaptation of out emotional reactions. Three key theories of anxiety development can be identified: insufficiency of control, generalization of fear, and hypersensibilization to threat. The first mechanism is most often linked to development of generalized anxiety disorder, the second theory reveals most fully the mechanisms of post-traumatic stress disorder development, while the hypersensibilization of prefrontal cortex best allows to explain sociophobia development. An important mechanism of development and chronification of various affective disorders is neuroinflammation, the role of which will also be highlighted in detail in this review. Understanding of the mechanisms of anxiety spectrum disorders development is important for differentiated drug and non-drug therapy and establishing the optimal strategy of treatment for such patients.