Synergistic Effects of Non-Invasive Brain Stimulation and Mindfulness Training on Pain and Self-Reported Mindfulness in Patients with Chronic Pain

Objective: This study aimed to evaluate the synergistic effects of combining non-invasive brain stimulation (NIBS) with mindfulness training on pain reduction and improvementsin self-reported mindfulness among patients with chronic pain. Although each intervention demonstrated modest benefits alone, their combined efficacy remains unclear. Design: A systematic review and meta-analysis.. Methods: A systematic search for relevant randomized controlled trials (RCTs) published up to May 2025 was conducted using the PubMed, Embase, CINAHL, and Web of Science databases. Studiescomparing noninvasive brain stimulation (tDCS or rTMS) combined with mindfulness-basedinterventions (MBIs) to control conditions in patients with chronic pain wereincluded. The primary outcomes were pain intensity and self-reportedmindfulness levels measured using validated scales (e.g., MAAS and FFMQ). Asingle investigator evaluated methodological quality with the Cochranerisk-of-bias tool and performed random-effects meta-analyses in RevMan 5.4. Results: Four randomized controlled trials (N = 127) were included. On analysis, the combined intervention did not produce a statistically significant reduction in pain intensity (SMD = −0.77; 95% CI: −1.67 to 0.13; p = 0.09), with moderate heterogeneity (I² = 52%). For self-reported mindfulness, the combined approach demonstrated a small and non-significant effect (SMD = –0.25; 95% CI: –0.74 to 0.24; p = 0.31), with low heterogeneity (I² = 1%). These findings indicated that the hypothesized synergistic effect of the combined intervention was not supported. Conclusions: Thisstudy indicates that, in patients with chronic pain, the combined interventionof noninvasive brain stimulation and mindfulness has limited effects onreducing pain and improving self-reported mindfulness. These findings may be attributed to the insufficient interventionintensity and duration, small sample sizes, and variability in stimulationprotocols. Future trials should adopt adequately powered designs with longerintervention periods and optimized stimulation parameters to clarify the potentialsynergistic effects of this combined approach for chronic pain management.