Accelerated intermittent theta burst stimulation for depressive disorder: A retrospective real-world study

Background Major depressive disorder (MDD) is a common and debilitating psychiatric disorder, causing extensive suffering and considerable societal costs. In clinical practice, repetitive transcranial magnetic stimulation (rTMS) is commonly used as a second-line treatment option (i.e. for treatment resistant depression). The most common rTMS protocol used in Sweden is intermittent theta burst stimulation (iTBS), typically applied over six weeks. Accelerated iTBS (aiTBS) may provide several advantages, e.g., shorter treatment cycles and faster onset, but integrating it into clinical practice can be challenging. Methods In this retrospective, register- and medical record-based study, data were collected from patients that received aiTBS treatment between January 2025 and December 2025 at Kungälv Hospital, Sweden. The treatment series included a total of 30 sessions administered over a maximum of two weeks. Treatment effects were assessed using the Montgomery-Åsberg Depression Rating Scale Self-Assessment (MADRS-S), the Clinical Global Impression scales (CGI-I / CGI-S), and the visual analogue scale of the EuroQol five-dimensional questionnaire (EQ VAS). Results Twenty-five patients, 16 inpatients and 9 outpatients, completed aiTBS treatment. There was a significant decline in clinician- and patient-rated depressive symptoms after treatment, and a significant improvement in subjective health. The treatment was well tolerated with no reported severe adverse events. Conclusion Depressive symptoms were significantly reduced and aiTBS treatment was well tolerated and clinically feasible. The findings should be interpreted with caution given the small sample size, lack of control group and retrospective design.