Genetic and Environmental Factors Involved in the Pathogenesis of Anxiety Disorders

Abstract

Background: Emotions such as anxiety and fear trace their origins back to ancient times, when they served an essential evolutionary function: namely, they contributed to appropriate responses to external stimuli that posed a threat to life or health, or even directly determined survival (for example, fleeing from a predator).

Methodology: A review was conducted using PubMed. Search terms included: anxiety, anxiety disorders, chronic stress, fear. Studies published between 2021 and 2025 were reviewed.

Results: Anxiety disorders and specific phobias have their roots in a stage of evolution when fear served as a warning mechanism and triggered an appropriate response to external threats. We speak of anxiety disorders when anxiety persists, is disproportionate to the situation—appearing in situations that do not pose a real threat—or significantly impairs an individual’s daily functioning, causing psychological distress. We attribute the underlying causes to mechanisms at the level of CNS neurotransmission, at the genetic level, as well as to an individual’s development and adverse environmental factors to which they are exposed from the very earliest stages of life—that is, beginning in the prenatal period.

Conclusions: Anxiety disorders have multiple causes and many predisposing or triggering factors, ranging from those encoded in genes, through hormonal imbalances, to environmental factors such as stress experienced in early life.