Abstract
Five-factor personality has been examined in relation to the natural history of depression and its response to treatment. With respect to rTMS, several five-factor personality dimensions have been associated with treatment outcomes, and open-label data suggests that neuroticism decreases with high-frequency stimulation to the left dorsolateral prefrontal cortex (DLPFC). Here, we examine the relationship between five-factor personality dimensions and antidepressant response leveraging a randomized placebo-controlled trial using the partial N-methyl- D-aspartate (NMDA) receptor agonist, D-Cycloserine, to enhance intermittent theta burst stimulation (iTBS). Methods In a 4-week double-blind randomized placebo-controlled trial, fifty individuals with major depressive disorder (NCT03937596) received iTBS+Placebo or iTBS+D-Cycloserine (100 mg). Participants completed the Big Five Inventory to assess five-factor personality dimensions, and depressive symptoms were assessed using the clinician rated Montgomery-Åsberg Depression Rating Scale at baseline and after the 4-weeks of treatment. Results There was no significant association between five-factor personality dimensions and change in depressive symptoms for either treatment group. Although iTBS+D-Cycloserine was associated with significantly greater antidepressant effect than iTBS+Placebo, neuroticism decreased with similar magnitude in each treatment group. Openness to experience and conscientiousness increased following treatment, and did so with similar magnitudes in both treatment groups. Conclusions These data suggest that five-factor personality may not predict antidepressant treatment outcomes with iTBS for major depressive disorder, and that decreases in neuroticism that have been reported in open-label TMS studies may reflect non-specific factors of treatment. Keywords major depressive disorder MDD D-Cycloserine NMDA receptor transcranial magnetic stimulation intermittent theta burst stimulation iTBS Five Factor Model
Authors
Watson, M., Protzner, McGirr, A. &., & A.
https://doi.org/10.1016/j.transm.2025.100196