Anxiety Disorder and BDNF: Integrative Review of the Literature

Abstract

Objective: To analyze the relationship between Brain-Derived Neurotrophic Factor (BDNF) and Anxiety Disorders (AD) and describe possible damage to the psychic functions in individuals with this disorder. Methods: this was an integrative review of the literature of articles published between 2008 and 2018, selected in the bibliographic databases of PubMed, Scielo and LILACS. Results and Discussion: In total, 28 articles were selected, of studies conducted with humans and animals. The relationship between levels of BDNF, including polymorphism in the BDNF gene, and AD was observed to have been approached, showing that the neurotrophic hypothesis could contribute to the physiopathology of ADs, including volumetric changes in regions of the brain, comprising psychic functions in patients with AD. Furthermore, studies have shown that the BDNF levels may reflect the effect of antidepressant or neuromodulation therapy, and that exposure to stressful factors may be related to individuals with this genetic variant being more vulnerable to developing AD. Conclusions: The data obtained in this research pointed towards an inverse relationship between BDNF levels and AD, and to the contribution of the neurotrophic hypothesis to the neurobiology of these disturbances, including damage to the psychic functions. Whereas considering that other studies to not show this relationship, further studies need to be conducted to validate a possible association. It was possible to hypothesize that BDNF, although unspecific, could be a biomarker associated with AD, and could be capable of helping with preventive actions to maintain mental health.