The influence of the repetitive transcranial magnetic stimulation on sleep quality in depression

Repetitive transcranial magnetic stimulation (rTMS) improves mood in depression. In this study we investigated whether the depression-related insomnia is modulated by this therapeutic method. We examined 13 patients (mean age 50.6±13.9; 11 women) with bipolar or unipolar depression. During 20 consecutive days, excluding Saturdays and Sundays, they underwent 20 daily sessions of 10 Hz rTMS over the left dorsolateral prefrontal cortex (DLPFC). Outcome measurement included the Clinical Global Impression (CGI), the 21item Hamilton Depression Rating Scale (HDRS), the Athens Insomnia Scale (AIS) as well as sleep diary and actigraphy. After rTMS, the CGI and HDRS total score decreased significantly. Also, the insomnia-related items of HDRS improved. The AIS showed trend towards decrease. No significant changes were present in sleep diaries and actigraphy. The beneficial effect of rTMS on the mood in depression has been confirmed. The rest of the results suggest high frequency rTMS to the left DLPFC does not have strong effects on sleep quality in patients with depression. Additional interventions or modification of the rTMS protocol should be considered to improve insomnia in these patients.