The Antidepressant Effect of Right Temporal Low Frequency rTMS Compared to Sham

The Antidepressant Effect of Right Temporal Kow Frequency rTMS Compared to Sham: A Clinical Controlled, Randomized, Blinded Study

The aim of the present study is to compare the antidepressant effect of low frequency rTMS applied over the right temporal cortex with sham stimulation.

TMS complies focal stimulation of the brain through a time varying magnetic field. Clinical controlled trials indicate that rTMS of the dorsolateral prefrontal cortex may have an antidepressant effect and no serious side effects. Several clinical controlled studies investigating the antidepressant effect of low as well as high frequency rTMS of the right and left prefrontal cortex have been carried out with varying results.Research on the issue suffer from small and selected study populations.There is a need for additional clinical controlled studies on larger samples and methodological investigations to clarify what is the optimal stimulus design for the treatment of depressed patients. Recent research indicates that Depression is associated with an increased metabolic activity of subcortical areas especially the right hippocampus of the brain. Remission of depression symptoms is associated with normalisation of the described subcortical hyperactivity. Low frequency rTMS has shown to be associated with sustained reduction in neuronal activity. There may be an association between the activity decreasing effect of low frequency rTMS and reduction in psychiatric symptoms. The investigators want to test the hypothesis that low frequency rTMS of the right temporal subcortical areas (Hippocampus and and the parahippocampal part of CNS) may perform an antidepressant effect by normalizing the described hyperactivity of the subcortical areas in depressed patients. In addition the investigators want to test whether blood concentration of Brain Derived Neurotropic Factor( BDNF), the BDNF-genotype and saliva cortisol may be of predictive value in depressed patients.

Depression, antidepressant effect, rTMS, sham, cognition, saliva cortisol, brain derived neurotropic factor

Low frequency ( 1 HZ) rTMS of the right prefrontal cortex. On each of 15 consecutive week days (apart from weekends), the patients received two 60-second1-Hz trains delivered at an intensity of 110% of motor thresholdand with a 180 seconds' intertrain interval.

Sham- rTMS of the right prefrontal cortex. On each of 15 consecutive week days (apart from weekends), the patients received two 60-second1-Hz trains delivered at an intensity of 110% of motor thresholdand with a 180 seconds' intertrain interval.

A Magstim Rapid stimulator (the Magstim Company Ltd, Whiteland, UK)with a 90 mm circular coil is used.

Inclusion Criteria: Inpatients admitted to Århus university Hospital , Risskov or outpatients from the psychiatry district centres or practising specialist in the area. Moderate - severe depression according to ICD-10/ DSM-IVR Age 18-80 years Total Hamilton score ( 17-items) of ≥ 18 or subscale score ≥ 9 Right handed Exclusion Criteria: Organic brain disease Epilepsy in growing age Metallic objects as the result of a chest or Brain surgery Cardiac pacemakers Somatic diseases associated with brain dysfunction Pregnancy Suicide risk of severe degree Severe agitation or delirium Alcohol and drug dependency Ongoing Electroconvulsive treatment

Klein E, Kreinin I, Chistyakov A, Koren D, Mecz L, Marmur S, Ben-Shachar D, Feinsod M. Therapeutic efficacy of right prefrontal slow repetitive transcranial magnetic stimulation in major depression: a double-blind controlled study. Arch Gen Psychiatry. 1999 Apr;56(4):315-20. doi: 10.1001/archpsyc.56.4.315.