Effiectiveness and safety of transcranial direct current stimulation in fibromyalgia: A systematic review and meta-analysis.

OBJECTIVE

To evaluate the effectiveness and safety of transcranial direct current stimulation for fibro-myalgia.

METHODS

Databases, conference records and registered trials were searched for articles published from the date of establishment of the database through to October 2015. Six randomized controlled trials (n=192) of transcranial direct current stimulation for fibromyalgia were included in the current study.

DATA EXTRACTION: Two researchers independently screened the literature, assessed methodological quality using the Cochrane Collaboration's tool, and extracted data.

DATA SYNTHESIS: Studies were divided into 3 groups for meta-analysis according to stimulation site and polarity. Significant improvement in pain and general fibromyalgia-related function was seen with anodal transcranial direct current stimulation over the primary motor cortex (p<0.05). However, the pressure pain threshold did not improve (p>0.05). Anodal transcranial direct current stimulation over the left dorsolateral prefrontal cortex did not significantly reduce pain or improve general fibromyalgia-related function compared with sham stimulation (p>0.05). Cathodal transcranial direct current stimulation over the primary motor cortex did not improve the pressure pain threshold compared with sham stimulation (p>0.05). No significant adverse effects were seen.

CONCLUSION

Anodal transcranial direct current stimulation over the primary motor cortex is more likely than sham transcranial direct current stimulation to relieve pain and improve general fibromyalgia-related function.