Department of Psychiatry, Ludwig-Maximilian-University, Nussbaumstr. 7, 80336,
An increasing number of clinical studies demonstrates antidepressant effects of
repetitive transcranial magnetic stimulation (rTMS). However, limited data are
available so far concerning the stability of these effects and the efficacy of
subsequent maintenance therapy. Therefore, we examined whether antidepressant
pharmacotherapy can stabilize clinical improvement after rTMS monotherapy.
Twenty-six drug-free patients suffering from a major depressive episode (DSM-IV
criteria) participated in an open rTMS trial over two weeks (10-13 sessions, 10
Hz, left prefrontal stimulation at 100% motor threshold intensity).
Subsequently, the patients were followed up during standardized antidepressant
pharmacotherapy with mirtazapine for a further 4 weeks. The interval between the
last rTMS and the first day of pharmacotherapy varied between one and five days.
After two weeks of rTMS monotherapy 39% of the patients responded to rTMS by at
least 50% reduction in their Hamilton Rating Scale for Depression (HRSD) scores.
Treatment interruption after rTMS resulted in a significant increase in the HRSD
score of rTMS responders. The degree of the deterioration was dependent on the
length of interval without treatment. However, this deterioration was reverted
and the further clinical course stabilized by subsequent mirtazapine treatment.
The overall response rate after rTMS and mirtazapine treatment (alone or in
combination) was 77%. Our results suggest that (1) antidepressant
pharmacotherapy is able to further improve the clinical response to rTMS and (2)
that responders to rTMS monotherapy should receive subsequent
psychopharmalogical treatment without interruption in order to avoid a
deterioration of symptoms.