Theta burst stimulation for depression: a systematic review and network and pairwise meta-analysis.

In clinical practice, theta burst stimulation (TBS) presents as a more efficient and potentially more effective therapeutic modality than conventional repetitive transcranial magnetic stimulation (rTMS), as it allows for the delivery of more stimuli in less time and at similar intensities. To date, accelerated treatment plans according to various continuous (cTBS) and intermittent TBS (iTBS) protocols for depression have been proposed. To investigate which of the TBS protocols provided a favorable risk-benefit balance for individuals with depression, this systematic review and random-effects model network meta-analysis was conducted. The study outcomes included response rate (primary), depression symptom improvement, remission rate, all-cause discontinuation rate, incidence of switch to mania, and incidence of headache/discomfort at treatment site. In this meta-analysis, a total of 23 randomized controlled trials (n = 960, mean age = 41.88 years, with 60.78% females) were included. Approximately 69.57% of the trials included individuals with an exclusive diagnosis of major depressive disorder. The following six TBS protocols (target) were evaluated: cTBS (right-dorsolateral prefrontal cortex [R-DLPFC]), cTBS (R-DLPFC) + iTBS (left-DLPFC [L-DLPFC]), iTBS (L-DLPFC), iTBS (L-DLPFC) + iTBS (R-DLPFC), iTBS (left-dorsomedial prefrontal cortex) + iTBS (right-dorsomedial prefrontal cortex), and iTBS (occipital lobe). Compared to sham, cTBS (R-DLPFC) + iTBS (L-DLPFC), iTBS (L-DLPFC), and iTBS (occipital lobe) had a higher response rate (k = 23); cTBS (R-DLPFC) + iTBS (L-DLPFC) and iTBS (L-DLPFC) dominated in the depression symptom improvement (k = 23); and iTBS (L-DLPFC) had a higher remission rate (k = 15). No significant differences were found for all-cause discontinuation rate (k = 17), incidence of switch to mania (k = 7), and incidence of headache/discomfort at treatment site (k = 10) between any TBS protocols and sham. Thus, cTBS (R-DLPFC) + iTBS (L-DLPFC) and iTBS (L-DLPFC) demonstrate favorable risk-benefit balance for the treatment of depression.

Suicidality and relief of depressive symptoms with intermittent theta burst stimulation in a sham-controlled randomized clinical trial.

OBJECTIVES: Suicidality is a serious public health problem and is closely associated with the severity of depression. In this work, we examined the effects of accelerated intermittent theta burst stimulation (iTBS) on suicidal status, risk factors for suicide, and severity of depressive symptoms in subjects with major depressive disorder (MDD). METHODS: We present data from a quadruple-blind (patient, care provider, investigator, rater) sham-controlled crossover randomized clinical trial. During a 6-week observation period, each participant underwent 2 weeks of stimulation - each week with 20 sessions of active or sham iTBS. A suicide score was created using a composite of individual items from Montgomery-Åsberg Depression Scale (MADRS), Hamilton Depression Scale, and Beck Depression Inventory. The severity of depression was determined by MADRS total scores. In addition, we used demographic and Columbia Suicidality Rating Scale information to assess suicide risk. RESULTS: Among 81 participants, we observed a significant reduction in suicidality and this change was positively correlated with a change in depressive symptoms. A significant difference between active and sham iTBS provided evidence for antidepressant effects. Higher changes in levels of anxiety and impulsiviness also correlated with larger changes in suicidality. CONCLUSIONS: As neither suicide nor other serious adverse events were evidenced, this intervention was a safe and viable procedure to reduce suicidality and severity of depressive symptoms. Moreover, we identified more pronounced anti-suicidal effects in those with higher risk profiles. Unlike MADRS, composite suicidal scores did not provide evidence of an effect between stimulation conditions in this crossover design study. Even so, based on our promising results, parallel and larger studies could contribute to a better characterization of the anti-suicidal placebo effect and the benefit of using iTBS against suicidal symptoms.

Accelerated intermittent theta burst stimulation in major depressive disorder: A systematic review.

BACKGROUND: Major depressive disorder [MDD] is expected to be the leading cause of overall global burden of disease by the year 2030 [WHO]. Non-response to first line pharmacological and psychotherapeutic antidepressive treatments is substantial, with treatment-resistant depression [TRD] affecting approximately one third of depressed patients. There is an urgent need for rapid acting and effective treatments in this population. Repetitive Transcranial Magnetic Stimulation [rTMS] is an non-invasive treatment option for patients with MDD or TRD. Recent studies have proposed new paradigms of TMS, one paradigm is accelerated intermittent Theta Burst Stimulation [aiTBS]. OBJECTIVE: This systematic review assesses the efficacy, safety and tolerability of aiTBS in patients with MDD. METHODS: This review was registered with PROSPERO [ID number: 366556]. A systematic literature review was performed using Pubmed, Web of Science and PsycINFO. Case reports/series, open-label and randomized controlled trials [RCTs] were eligible for inclusion if they met the following criteria; full text publication available in English describing a form of aiTBS for MDD or TRD. aiTBS was defined as at least three iTBS treatments sessions per day, during at least four days for one week. RESULTS: 32 studies were identified describing aiTBS in MDD, 13 studies described overlapping samples. Six articles from five unique studies met eligibility criteria; two open-label studies and three RCTs [two double blind and one quadruple blind]. Response rates directly after treatment ranged from 20.0% to 86.4% and remission rates ranged from 10.0 to 86.4%. Four weeks after treatment response rates ranged from 0.0% to 66.7% and remission rates ranged from 0.0% to 57.1%. Three articles described a significant reduction in suicidality scores. aiTBS was well tolerated and safe, with no serious adverse events reported. CONCLUSIONS: aiTBS is a promising form of non-invasive brain stimulation [NIBS] with rapid antidepressant and antisuicidal effects in MDD. Additionally, aiTBS was well tolerated and safe. However, the included studies had small samples sizes and differed in frequency, intersession interval, neuro localization and stimulation intensity. Replication studies and larger RCTs are warranted to establish efficacy, safety and long term effects.