Impact and safety of transcranial direct current stimulation in patients with systemic autoimmune rheumatic diseases

Abstract

Systemic autoimmune rheumatic diseases (SARDs) are comprised by a variety of diseases that may affect several organs and systems, including joints, muscles, and nerves. Despite drug treatment and guidance on performing regular physical exercises, the high frequency of fatigue, motor deficits, and chronic pain in these patients is remarkable. These factors, in turn, impair functional capacity and quality of life, generating vicious cycle between these symptoms. Thus, it becomes relevant to establish therapeutic strategies that may result in a decrease or break in this vicious cycle. Several studies have shown the efficacy of using transcranial non-invasive neuromodulation (e.g., transcranial electrical current stimulation - tDCS) in several diseases to reduce fatigue, modulate and reduce pain, and consequently improve functional capacity and quality of life. However, to date, there is a scarcity of studies evaluating the safety and benefit of tDCS in patients with SARDs, reasearch has been limited two studies (initially, on systemic autoimmune myopathies, and afterward one on Sjögren's syndrome). Of note, our group has been pioneering in our study of benfetic and safety of tDCS specifically in these patients with systemic autoimmune myopathies.In this context, the present project aims to perform a greater number of sessions of tDCS, associated with physical exercises, in different kinds of SARDs (e.g., systemic lupus erythematosus and primary systemic vasculitis - Takayasu arteritis). The effectiveness of the technique (on local and diffuse pain, fatigue, overall functionality, functional capacity, and quality of life) will be evaluated. This combination of central and peripheral techniques may result in na increase neuroal network connectivity, promote additional effects on muscle excitability, thus contributing to decrease in perceived pain and fatigue, which itself could result in greater muscle recruitment, improved muscle strength and function, and enhanced mobility and balance. In summary, an improvement in functional capacity and quality of life in patients with SARDs may indicate the utility of these techniques for clinical and rheumatologic practice. (AU)