Previous studies have shown safety and efficacy of deep repetitive transcranial magnetic stimulation (DTMS) in treatment-resistant depression. However, little is known about predictors of response; i.e. it is difficult to predict which patients will benefit from the treatment. The aim of this study was to investigate the role of personality traits in predicting antidepressant effects of DTMS.

A total of 68 consecutive patients diagnosed with major depressive disorder (MDD) were treated with daily DTMS over the left dorsolateral prefrontal cortex for 4 weeks. At baseline, patients completed the IPIP50 (a five-factor assessment of major personality dimensions), Brief COPE (assessment of a broad range of coping responses), and LOTR-R test (measure of optimism versus pessimism). Antidepressant effects of DTMS were measured using the 21-item Hamilton Depression Rating Scale (HAMD) at baseline and at the conclusion of the treatment.

Clinical remission (HAMD≤9) was observed in 73% of the patients. Those who achieved remission had significantly higher baseline levels of conscientiousness, intellect/imagination and optimism, as well as higher scores on using humour, acceptance and religion as coping strategies, compared to other patients. Also, correlations were calculated between scores on personality traits and percentage improvement in HAMD scores. Significant positive associations were observed for dimensions of conscientiousness and intellect/imagination, and coping mechanisms: positive reframing, humour and acceptance.

The assessment of personality traits may have prognostic value in DTMS treatment for MDD. Further studies are needed to better clarify these preliminary findings.