Anodal stimulation of primary motor cortex in elderly women with fibromyalgia: A randomized, double-blind, placebo-controlled trial

Abstract

It is thought that an excessive motor cortical facilitation is involved in the physiopathology of chronic pain in fibromyalgia. Studies have shown that transcranial direct current stimulation (tDCS) changes motor cortex excitability according to the stimulation polarity. Based on these effects, it is conceivable to hypothesize that tDCS, which can modulate brain activity, may induce pain relief in patients with fibromyalgia. Fifty older women with fibromyalgia were included in this randomized, doubleblind, single-center placebo-controlled trial study. Patients received sham stimulation or real tDCS with the anode centered over the primary motor cortex (M1) and the cathode over the contralateral supraorbital area (2 mA for 20 minutes for 10 sessions). Pain intensity was evaluated using the visual analog scale for pain. Assessments were done before treatment and 30 days after the last session of stimulations. The mean age of participants was 58.20 years (SD = 7.80) with an age range from 55 to 74 years.Results showed no statistically significant baseline difference among patients in demographics and clinical characteristics. Comparing visual pain analogue between the sham and treatment groups revealed a statistically significant difference (p value < 0.001) for VAS immediately after intervention and 1 month post intervention between the sham and treatment groups. Analysis of data also showed a significant reduction in pain immediately after intervention and one month post-intervention in the treatment group compared to the sham group. Anodal tDCS is an effective non-invasive technique for pain reduction in elderly women with FM. The clinical improvements observed in the current study may have considerable impacts on pain experienced by elderly women with FM.