Transcranial Direct Current Stimulation for the treatment of generalized anxiety disorder: A Randomized Clinical Trial.
Anxiety. Depression. Transcranial Direct Current Stimulation. Rehabilitation.
Introduction: Anxiety is a disorder that has been affecting a great number of individuals and Brazil being the country with the highest prevalence in Americas with 9.3%. Among the anxiety disorders, there is the generalized anxiety disorder (GAD), characterized mainly by tremors, muscular hypotonia, hyperventilation, sweating, palpitations, apprehension, restlessness, distractibility, loss of concentration and insomnia. GAD cause impairment in the functional, social, affective and cognitive life of the individual, thus, there is a need for an effective treatment that can minimize these effects. One of the techniques that has been used with positive results for treatments of some psychiatric disorders is Transcranial Continuous Current Stimulation (tDCS), which is a noninvasive neuromodulation technique that, through an electric microcurrent of 0, 5 to 2 mA cause stimulation or inhibition of neuronal activity. This stimulation causes specific changes in the behavior and motor activity of individuals by modulating specific brain areas. Despite many studies of tDCS in mood disorders, such as depression, and some studies in anxiety disorders such as panic, tDCS studies with GAD are still incipient. Thus, there is a need to evaluate the effects that tDCS can have on people affected by GAD. Objectives: To analyze the effects of anodic tDCS over the left dorsolateral prefrontal cortex (CPFDL) in people affected by GAD, presenting possible improvements in the symptoms of the disease. The study was designed as a randomized double-blind clinical trial, with a sample of 30 participants aged 20 to 40 years who had a clinical diagnosis of GAD according to the criteria of the American Psychiatric Association (DSM-V). Participants were divided into two groups, sham and experimental group, and the allocation was performed in a randomized, double-blind fashion. Results: No differences were found for anxiety, depression and affectivity. However, a significant improvement was found in the active group for physical symptoms of stress. Although intragroup analyzes showed decreases in anxiety, stress, negative affectivity, and depression scores, no intergroup comparison showed significant difference. Improvement in physical aspects of stress in GAD can improve life satisfaction, cognitive function, and psychological well-being. Conclusion: It is suggested that five sessions of anodic tDCS on CPFDL did not improve anxiety and mood symptoms in patients with GAD. However, the protocol showed improvement in physical symptoms of stress.