Effect of home-based transcranial direct current stimulation combined with nutritional counseling therapy on binge eating disorder symptoms : a randomized pilot trial

Abstract

Objective: To examine the effect of nutritional counseling therapy (NCT) combined with transcranial direct current stimulation (tDCS) on binge eating disorder (BED) symptoms. Methods: Forty women with BED were randomly allocated (2:2:2 ratio) to one of the following groups: active tDCS (a-tDCS), NCT, sham tDCS (s-tDCS) with NCT, and a-tDCS with NCT. Home-based tDCS was applied to the dorsolateral prefrontal cortex for 28 sessions. Results: A mixed analysis of variance (ANOVA) showed no main effect between groups nor a time group interaction. However, a significant main effect was found for time on the primary outcome Binge Eating Scale (BES) (p = 0.001; eta2p = 0.325), which tended to decrease during treatment and followup. A significant main effect was found for the secondary outcome short-interval intracortical inhibition (SICI) (p = 0.02; eta2p = 0.112), a measure of inhibitory function, which increased from baseline to the final period in the a-tDCS group, without significant differences between groups. Conclusion: Combined NCT and tDCS did not have a synergistic effect on BED symptoms. Nevertheless, the data from this pilot study should help plan future larger-scale studies investigating the effects of tDCS and behavioral interventions in the promising area of BED treatment. Clinical trial registration: ClinicalTrials.gov: NCT 04226794. Registered on July 2, 2019.