Antidepressant efficacy of two different rTMS procedures. High frequency over left versus low frequency over right prefrontal cortex compared with sham stimulation.

Abstract

This placebo-controlled study was designed to investigate the influence of two different stimulation procedures of repetitive transcranial magnetic stimulation (rTMS) on depressive symptoms in patients with depressive disorders. Furthermore, effects on cognitive functions and psychomotor functioning were tested. Thirty patients with depression (22 females and 8 males; mean age of 56.4 years) were included. They were treated with a stable dosage of antidepressant medication. They received either high frequency rTMS (20 Hz) over the left dorsolateral prefrontal cortex (LDLPFC), low frequency rTMS (1 Hz) over the right dorsolateral prefrontal cortex (RDLPFC) or sham stimulations (10 patients in each group) as add on treatment at 10 days within 2 weeks. Depressive symptoms were registered by means of observer ratings (Hamilton Depression Rating Scale - HDRS) and self reports (Beck Depression Inventory - BDI). Psychomotor retardation was investigated by the Motor Agitation and Retardation Scale and cognitive function by d2 test. Differences between the rTMS procedures regarding depressive symptoms could not be found. Motor abnormalities, however, significantly improved exclusively after real stimulation procedures. Patients with less severe deficits in psychomotor speed and concentration responded more intensively than patients with severe deficits.