Combining Transcranial Direct Current Stimulation With Non-Invasive Interventions for Chronic Primary Pain: A Systematic Review and Meta-Analysis.

Background: A growing number of studies has combined transcranial direct current stimulation (tDCS) with other non-invasive non-pharmacological therapies (NINPT) to enhance effects in pain reduction. However, the efficacy of these combined approaches in treating chronic primary pain (CPP) warrants thorough investigation.

Objective: This study aims to evaluate the efficacy of tDCS in conjunction with other NINPT in alleviating pain severity among CPP patients.

Methods: We conducted a systematic search for randomized controlled trials (RCTs) comparing the efficacy of tDCS combined with NINPT against control treatments in adult CPP patients. The search spanned multiple databases, including PubMed, EMBASE, LILACS, Scopus, Web of Science, and CENTRAL.

Results: Our systematic review included 11 RCTs with a total of 449 participants. In our meta-analysis, which comprised 228 participants receiving active-tDCS and 221 receiving sham-tDCS, we found a significant reduction in pain intensity (Standard Mean Difference = -0.73; 95% Confidence Interval (CI) = -1.18 to -0.27;  = .002) with the use of active-tDCS combined with NINPT.

Conclusion: These findings substantiate the therapeutic potential of combining tDCS with other NINPT, highlighting it as an effective treatment modality for reducing pain intensity in CPP patients.