Lifestyle and anxiety disorders: BDNF, a possible biomarker?

Abstract

Introduction: Anxiety disorders (AD) are brain disturbances related to neurotransmitter circuits and neuroanatomic changes that are aggravated by unhealthy lifestyle. In turn, the brain derived neurotrophic factor (BDNF), a neurotrophin responsible for cerebral plasticity, is related to alteration volume in some brain structures and it can be explained by some lifestyle factors. Objective: to analyze the relationship between BDNF and AD and describe possible damage to the psychic functions in individuals with these disorders. 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: In total, 28 articles were selected, of studies conducted with humans and animals. The relationship between levels of BDNF, 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. 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.