Effect of Transcranial Alternating Current Stimulation on Ataxia Symptoms of Spinocerebellar Ataxia Type 3: A Randomized Clinical Trial

Abstract Currently, there are no treatments to alter the natural course of spinocerebellar ataxia type 3 (SCA3). Transcranial alternating current stimulation (tACS) have the sustainable potential to alleviate SCA3. Therefore, we conducted a randomized controlled trial enrolling 158 patients with SCA3 to investigate the safety and efficacy of tACS (NCT05557786). Enrolled participants received Active-tACS or Sham-tACS treatment 5 days/week for 2 weeks. The primary outcome was the proportion of participants whose Scale for the Assessment and Rating of Ataxia score improved by at least 1.5 points compared with baseline on assessments immediately after treatment and at 1-month and 3-month follow-up visits. The primary outcome assessed in the intention-to-treat population was met by 32 of 40 patients in the active-tACS group (80%) and 4 of 40 patients in the sham-tACS group (OR, 2.04[95% CI, 1.75 to 2.38; P < 0.001]). These promising findings motivate additional study to establish guidelines for tACS as a clinically recommended treatment for cerebellar diseases.