ABSTRACT
The antidepressive potency of repetitive transcranial magnetic stimulation (rTMS) seems to depend on variables such as the stimulation placements, different frequencies, stimulus intensities, coil shape and interstimulus intervals. The aim of this pilot study was to investigate the augmentation properties of rTMS combining low and high frequencies. Thirty six depressed medicated in-patients were recruited and assigned to three different rTMS treatment modalities as an add-on strategy (each n = 12). In group 1 a stimulus intensity of 110% of the motor threshold (MT) was used with a frequency of 10 Hz over the left dorsolatero prefrontal cortex (DLPC). The right DLPC was stimulated in the same session with 110% MT at 1 Hz. In group 2 the patients were stimulated only over the left DLPC with alternating trains of 110% MT at 10 Hz and trains of 110% MT at 1 Hz in the same session. In group 3 the high frequency stimulation over the left DLPC was performed as an internal control group. None of the treatment modalities was superior but different side effects were observed. These preliminary findings suggest that rTMS, at varying frequencies and stimulation placements, evokes different psychoactive effects of clinical relevance.
Subject(s)
Depressive Disorder/therapy , Electromagnetic Fields , Depressive Disorder/psychology , Electromagnetic Fields/adverse effects , Female , Functional Laterality/physiology , Humans , Male , Middle Aged , Personality Disorders/complications , Personality Disorders/psychology , Pilot Projects , Prefrontal Cortex/physiology , Prefrontal Cortex/radiation effects , Psychiatric Status Rating Scales , Treatment OutcomeABSTRACT
Research on single and rapid transcranial magnetic stimulation (sTMS/rTMS) indicates an antidepressive efficacy of these methods. In our 4 week study of sTMS, 12 patients affected by severe non-psychotic major depression (DSM-III-R) were enrolled and put on standardized combined antidepressant medication with the serotonin re-uptake inhibitor citalopram, and the serotonin modulating drug, trazodone. They underwent sTMS in a specific method as an add-on therapy. Age, gender, illness and episode duration, episode number, Hamilton Rating Depression Scale-24 (HRDS), Mini-Mental State (MMS), drug levels assessed by HPLC, magnesium and thyroid stimulating hormone (TSH) were recorded. For each patient functional brain imaging was performed by (18)FDG and (99m)Tc HMPAO SPECT at the beginning of the study, as were EEG tracings which also were recorded at the end. Lorazepam was allowed as co-medication. Of the patients, 66.7 per cent (N=8) could be identified as sTMS responders. Possible predictors for sTMS response as add-on therapy may be duration, pattern of improvement in global and in specific single items of the HRDS, lorazepam dosage, functional involvement of basal ganglia and cortical temporal lobe and the initially lower mean frequency and lability of the alpha-activity of EEG. These variables possibly predict the clinical outcome of depressed patients treated by sTMS as an add-on therapy. Copyright 2000 John Wiley & Sons, Ltd.
