The Antidepressant Effect of Repetitive Transcranial Magnetic Stimulation (rTMS)Compared to ECT

Previous clinical controlled trials indicate that repetitive transcranial magnetic stimulation (rTMS) of the prefrontal cortex may relieve antidepressant symptoms. Most of these studies have used high frequency stimulation of the left frontal cortex. A few investigations have found that right frontal low frequency rTMS, which constitute a more gentle stimulus design has an antidepressant effective at the same level. Compared to ECT rTMS has obvious advantages. The new method implies focal stimulation of the brain, is not inducing epileptic seizures and does not require anesthesia. In addition rTMS does not seem to induce cognitive disturbances. Few studies have compared the antidepressant effect of rTMS with that of ECT. The main outcome indicates that high frequency rTMS of the left frontal cortex has an antidepressant effect which is comparable to that of ECT in the treatment of non-psychotic patients. It is difficult to draw definite conclusions from these studies, first of all because of small and highly selected study populations. In addition different stimulus designs make most of the mentioned studies incomparable.

The aim of the present study is to compare the antidepressant effect of low frequency rTMS of the right dorsolateral prefrontal cortex with ECT in a hospitalized population of major depressed patients (ICD-10/DSM-IV) in a randomized open noninferiority study.

About fifty percent of depressed patients have shown to be associated with an increased plasma cortisol concentration and HPA-axis activity expressed in non-suppression of plasma cortisol in association with the dexamethasone (DX-test) suppression test. Some studies have shown that the presence or absence of normalization of the HPA-axis activity and the DX-test during antidepressant treatment may be a predictor of recurrence. Other studies have shown that the physiological increase in the concentration of saliva cortisol during the first half an hour after awakening in the morning is accentuated in depressed patients and constitute a more simple expression of the HPA-.axis activity and predictor of outcome than the the dx-test.

Therefore we want to investigate the value of the increase in the morning cortisol concentration during the first half an hour after awakening as a predictor of antidepressant effect and outcome.

Inclusion criteria

• Admission to Psychiatric Hospital in Aarhus.
• The patient should be candidate for ECT.
• Moderate or severely depressed/Major depressed (ICD-10/DSM-IV)
• A total score on the Hamilton (17-item) rating scale for depression of 20 or above, or a subscale score of 10 ore above.
• Right handed,
• Age 18-80 years

Exclusion criteria

• Organic brain disease
• Epilepsy
• Metal devices in operated into the brain or chest.
• The patient is wearing cardiac pacemaker.
• Medical illness associated with disturbed CNS function
• Pregnancy
• Serious suicidality
• Severe agitation or delirium
• Alcoholic or drug dependency
• The patients exposed to coercive measures