Left prefrontal transcranial magnetic stimulation (TMS) treatment of depression in bipolar affective disorder: a pilot study of acute safety and efficacy.
OBJECTIVE
Repetitive transcranial magnetic stimulation (rTMS) has been shown to improve depressive symptoms. We designed and carried out the following left prefrontal rTMS study to determine the safety, feasibility, and potential efficacy of using TMS to treat the depressive symptoms of bipolar affective disorder (BPAD).


METHODS
We recruited and enrolled 23 depressed BPAD patients (12 BPI depressed state, nine BPII depressed state, two BPI mixed state). Patients were randomly assigned to receive either daily left prefrontal rTMS (5 Hz, 110% motor threshold, 8 sec on, 22 sec off, over 20 min) or placebo each weekday morning for 2 weeks. Motor threshold and subjective rating scales were obtained daily, and blinded Hamilton Rating Scale for Depression (HRSD) and Young Mania Rating Scales (YMRS) were obtained weekly.


RESULTS
Stimulation was well tolerated with no significant adverse events and with no induction of mania. We failed to find a statistically significant difference between the two groups in the number of antidepressant responders (>50% decline in HRSD or HRSD <10 - 4 active and 4 sham) or the mean HRSD change from baseline over the 2 weeks (t = -0.22, p = 0.83). Active rTMS, compared with sham rTMS, produced a trend but not statistically significant greater improvement in daily subjective mood ratings post-treatment (t = 1.58, p = 0.13). The motor threshold did not significantly change after 2 weeks of active treatment (t = 1.11, p = 0.28).


CONCLUSIONS
Daily left prefrontal rTMS appears safe in depressed BPAD subjects, and the risk of inducing mania in BPAD subjects on medications is small. We failed to find statistically significant TMS clinical antidepressant effects greater than sham. Further studies are needed to fully investigate the potential role, if any, of TMS in BPAD depression.
Nahas
Ziad
Z
Brain Stimulation Laboratory, Department of Psychiatry, Medical University of South Carolina, Charleston 29425, USA.
Kozel
F Andrew
FA
Li
Xingbao
X
Anderson
Berry
B
George
Mark S
MS
D000328:Adult; D000342:Affective Symptoms; D001714:Bipolar Disorder / Q000503:physiopathology / Q000628:therapy*; D003866:Depressive Disorder / Q000628:therapy*; D004311:Double-Blind Method; D004574:Electromagnetic Fields; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009048:Motor Skills; D010865:Pilot Projects; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D050781:Transcranial Magnetic Stimulation / Q000627:therapeutic use*; D016896:Treatment Outcome