Adjunctive continuous theta burst stimulation for major depressive disorder or bipolar depression: A meta-analysis of randomized controlled studies

Objectives: As a novel type of theta burst stimulation (TBS), continuous TBS (cTBS) has been shown to have mixed therapeutic effects for major depressive disorder (MDD) or bipolar depression (BD). Thus, we performed a meta-analysis of randomized controlled trials (RCTs) of cTBS for treating major depressive episodes in patients with MDD or BD.

Methods: A systematic search of four major bibliographic databases (PubMed, EMBASE, Cochrane Library, and PsycINFO) was conducted from inception dates to February 3, 2023 to identify eligible studies. The data were analyzed using a random-effects model.

Results: Three RCTs (n = 78, active cTBS = 37 and sham cTBS = 41) were included the meta-analysis. No significant differences were found in terms of change in Hamilton Depression Rating Scale (HAMD) scores (3 RCTs, n = 78, SMD = -0.09, 95 % CI: -0.53 to 0.36; I² = 0 %; P = 0.71) and study-defined response (2 RCTs, n = 58, 26.7 % versus 21.4 %, RR = 1.20, 95 % CI: 0.48 to 2.96; I² = 0 %; P = 0.70) between active and sham cTBS groups. Similarly, no group differences were found in the rates of adverse events and discontinuation due to any reason (P > 0.05).

Limitations: Meta-analysis had small sample sizes and low number of included studies.

Conclusions: Although cTBS appeared to be a safe and well-tolerated option for treating major depressive episodes in MDD or BD patients, no advantage in treatment effects was found in this meta-analysis. Future large-scale studies are warranted to assess the efficacy of cTBS for MDD or BD patients with a major depressive episode.