Efeitos da estimulação transcraniana por corrente contínua e de biomarcadores sanguíneos no comprometimento cognitivo leve

Abstract

Mild cognitive impairment (MCI) refers to the transitional state between the cognitive changes of normal aging and early dementia, but does not noticeably interfere with activities of daily living. MCI is believed to be a prodromal stage of dementia that causes severe cognitive dysfunction, so its identification for early intervention is considered an important therapeutic strategy. In this context, non-pharmacological interventions, such as Transcranial Direct Current Stimulation (tDCS), which uses direct electrical currents to stimulate specific parts of the brain, have been used to clinically improve these patients. Biochemical processes are associated with the pathogenesis of MCI and dementia, and with this comes the need for blood biomarkers that can optimize clinical practice. Therefore, the general objective of this study was to evaluate the effects of tDCS on the cognitive function of patients with MCI and to identify the influence of possible blood biomarkers in this clinical condition. Two studies were developed, the first consisted of a systematic review and meta-analysis to identify evidence on the diagnostic accuracy parameters of cytokines (IL-6, IL-10 and TNF-α) in CCL and the second a randomized clinical trial and double-blind study that aimed to evaluate the effects of Transcranial Direct Current Stimulation (tDCS) on the cognitive function of individuals with MCI. The systematic review (study 1) concluded that the involvement of inflammatory cytokines as a biomarker for detection of MCI is still uncertain and needs to be better investigated. The randomized clinical trial (study 2) was developed with a CCL group and the volunteers were divided into 2 intervention groups: active or sham tDCS group and no significant differences were observed between groups, even when exploratory analyzes were applied for those who responded to the treatment. Despite the limitations of the articles developed, such as the scarcity and heterogeneity of the studies in the first article and the small sample in the second article, it is hoped that these findings are encouraging for further investigations.