Accelerated intermittent theta-burst stimulation for major depressive episodes: systematic review and dose-response...

Area of Science:

• Neuroscience
• Psychiatry
• Clinical Trials

Background:

• Intermittent theta-burst stimulation (iTBS) is effective for major depressive episodes (MDE) but time-consuming.
• Accelerated iTBS (aiTBS) offers reduced treatment duration via multiple daily sessions.
• Heterogeneous aiTBS parameters have led to inconsistent outcomes.

Purpose of the Study:

• To systematically review and meta-analyze randomized sham-controlled trials of aiTBS for MDE.
• To assess the efficacy and acceptability of aiTBS compared to sham.
• To explore factors influencing aiTBS effectiveness, including target location and dose.

Main Methods:

• Systematic review and meta-analysis of 15 randomized sham-controlled trials (n=704) in adults with MDE.
• Primary outcomes: depressive symptom improvement (SMD) and acceptability (discontinuation rates).
• Secondary outcomes: response/remission rates (RR, NNT), with exploratory analyses on protocol parameters.

Main Results:

• aiTBS significantly reduced depressive symptoms (SMD=0.69) and improved response (RR=1.99, NNT=5) and remission (RR=1.77, NNT=10) versus sham.
• Acceptability was comparable between aiTBS and sham groups (discontinuation rates 6.96% vs 8.12%).
• Higher session frequency, total pulses, intersession intervals, and functional connectivity neuronavigation correlated with enhanced effects.

Conclusions:

• aiTBS is a validated and effective treatment for MDE.
• Optimizing aiTBS protocols, potentially with neuronavigation and higher intensity, may further enhance treatment outcomes.
• Further research is recommended to refine aiTBS parameters for maximal efficacy.