Maintenance Transcranial Magnetic Stimulation for Depression: A Meta-analysis

Introduction: The optimal strategy for delivering TMS beyond acute treatment in patients who have achieved optimal clinical response remains unclear. This meta-analysis aims to quantify the treatment effect of maintenance TMS beyond acute treatment and compare the differene in treatment effect between the two strategies. Method: We conducted a meta-analysis of 14 studies (Nf705) comparing depression scores before and after maintenance TMS. Standardized mean scores adjusted for sample size were used as the effect size. Subgroup analysis was performed to compare the treatment effect of rescue treatment versus fixed maintenance treatment. Results: Maintenance TMS was associated with a statistically significant improvement in depression scores (SMD=0.75, 95% CI -1.2477; -0.2451). The subgroup analysis showed a stronger treatment effect for rescue maintenance treatments (SMD = -1.17, 95% CI [-2.13, -0.21], k = 6) compared to fixed maintenance treatment (SMD = -0.45, 95% CI [-1.05, 0.16], k = 8). Although the difference between subgroups was not statistically significant (Q between = 2.56, df between = 1, p = 0.1096), a large difference in effect size was observed. Conclusion: Maintenance TMS appears to be an effective strategy for maintaining remission and preventing relapse in depression. While sub-group analysis did not show a significant difference between rescue and fixed maintenance treatments, further research is needed to confirm the results and identify potential moderators of treatment effects. These findings suggest the need for standard protocols or expert consensus guidelines for the optimal delivery of TMS beyond acute treatment.