Efeitos da estimulação transcraniana por corrente contínua (ETCC) associada ao treino de equilíbrio em indivíduos com Parkinson: ensaio clínico randomizado

Abstract

Introduction: Parkinson's disease (PD) is a progressive and chronic disorder of the Central Nervous System (CNS) that results in disturbances in balance, gait and postural control. Among the resources available for treatment is Transcranial Direct Current Stimulation (tDCS), which consists of the application of low-intensity continuous electrical current through two surface electrodes (cathode and anode), capable of generating neurophysiological effects through of the excitability of cortical and subcortical neurons, and has been discussed in the literature as a neuromodulatory intervention capable of facilitating neural activity in regions that present hypoactivation, as well as inhibiting hyperactive areas. Some studies have investigated the use of tDCS in the cerebellar region, however, there is an extremely limited amount of evidence that allows the conclusive generation of the effects of tDCS in PD, especially when it comes to the evaluation of cerebellar stimulation in postural control in patients with PD, whether associated with exercise protocols. Objective: To investigate the effects of balance training associated with cerebellar tDCS on postural control in individuals with PD. Methods: This is a randomized clinical trial. Accepting the possibility of 20% possible sample loss, the selection of 36 patients with PD was considered. Individuals were screened by collecting sociodemographic data and health information, International Physical Activity Questionnaire (IPAQ), Hoehn & Yahr (included 3 and 4) and 10-Point Cognitive Screener (10-CS) (excluded individuals with scores less than 8). Randomization was generated by computer by an independent researcher, through block randomization, allocating individuals to an experimental group (GE) or placebo group (GP). To evaluate postural control, MiniBESTest and a 10m walk test were used, using Baiobit equipment. In both groups, a conventional protocol of 10 Physiotherapy sessions was applied for locomotor training and postural control. In the GE, tDCS was applied, with a current setting of 1.5 mA for 20 minutes simultaneously with postural control training. In the PG, tDCS was applied in sham mode, with the same electrode positioning and the same number of sessions as the EG. Results: The sample comprised 32 individuals with PD (GE: 16; GP: 16). The sample was homogeneous in its socioeconomic and health characteristics, with no significant differences between the groups. The balance exercise protocol proved to be effective, indicating clinically significant effects on the participants' postural control. However, there was no significant difference in the intergroup analysis, suggesting that the use of tDCS in the cerebellum was not able to enhance the exercise gains in the GE. Conclusions: The results obtained in this study indicate that the exercise protocol was effective in promoting improvements in postural control in individuals diagnosed with PD in Hoehn & Yahr stages 3 to 4, while tDCS was not shown to significantly influence the results.