The goal of this study was to investigate the utility of the Temperament and Character Inventory (TCI) in predicting antidepressant response to repetitive transcranial magnetic stimulation (rTMS).
Although rTMS of the dorsolateral prefrontal cortex is an established antidepressant treatment, little is known about predictors of response. The TCI measures multiple personality dimensions (harm avoidance, novelty seeking, reward dependence, persistence, self-directedness, self-transcendence, and cooperativeness), some of which have predicted response to pharmacotherapy and cognitive-behavioral therapy. A previous study suggested a possible association between self-directedness and response to rTMS in melancholic depression, although this was limited by the fact that melancholic depression is associated with a limited range of TCI profiles.
Nineteen patients with a major depressive episode completed the TCI before a clinical course of rTMS over the dorsolateral prefrontal cortex. Treatment response was defined as ≥50% decrease in scores on the Hamilton Rating Scale for Depression (Ham-D). Baseline scores on each TCI dimension were compared between responders and nonresponders through analysis of variance. Pearson correlations were also calculated for temperament/character scores in comparison with percentage improvement in Ham-D scores.
Eleven of the 19 patients responded to rTMS. T-scores for persistence were significantly higher in responders than in nonresponders (P=0.022). Linear regression revealed a correlation between persistence scores and percentage improvement in Ham-D scores.
Higher persistence scores predicted antidepressant response to rTMS. This may be explained by rTMS-induced enhancement of cortical excitability, which has been found to be decreased in patients with high persistence. Personality assessment that includes measurement of TCI persistence may be a useful component of precision medicine initiatives in rTMS for depression.
SIDDIQI, CHOCKALINGAM, CLONINGER, LENZE, and CRISTANCHO: Department of Psychiatry, Washington University School of Medicine in St Louis, St Louis, MO
Supported by the National Institute of Mental Health of the National Institutes of Health under award R34MH101433.
The Content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
The authors acknowledge the Center for Well-Being, Washington University in St Louis, for administration and scoring of Temperament and Character Inventories (TCI) as well as travel support to S.H.S. to present preliminary findings at the 2015 meeting of the International Society for ECT and Neuromodulation 2015 meeting in Toronto. C.R.C. holds the copyright for the TCI and its distribution.
The authors declare no conflict of interest.
Please send correspondence to: Shan H. Siddiqi, MD, Department of Psychiatry, Washington University School of Medicine in St Louis, P.O. Box 8134, 660 S Euclid Ave., St Louis, MO 63110 (e-mail: email@example.com).