Neurobiologische Befunde und klinische Ergebnisse

Zusammenfassung

Präklinische Studien haben gezeigt, dass die repetitive transkranielle Magnetstimulation (rTMS) dorsolateraler präfrontaler Kortexareale die Funktion fronto-limbischer Regelkreise modulieren kann und somit bei Depressionen bestehende Funktionsveränderungen in diesem System günstig beeinflussen könnte. Darüber hinaus wurden Effekte auf verschiedene Neurotransmittersysteme, u.a. dopaminerge Effekte, und auf die bei depressiven Patienten oft bestehende Dysregulation der Hypophysen-Hypothalamus-Nebennieren-Achse gefunden. Mehrere plazebokontrollierte klinische Studien mit allerdings kleinen Fallzahlen haben in der Mehrzahl signifikante Unterschiede zwischen den Verum- und Plazebo-Gruppen ergeben. Bislang fehlen allerdings noch umfangreichere Studien, wie sie für den Wirksamkeitsnachweis bei antidepressiven Medikamenten üblich sind. Zukünftige Studien sollten insbesondere spezifische Indikationen (z.B. Primärtherapie, Augmentation, Erhaltungstherapie) näher untersuchen.

Summary

Preclinical findings show that repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex can modulate the function of fronto-limbic circuits, which is reversibly altered in major depression. rTMS has also been found to exert effects on different neurotransmitter systems, e.g. dopaminergic effects, and to act on the hypothalamic pituitary adrenal (HPA) axis, which is often dysregulated in major depression. In the majority of controlled clinical studies, significant differences have been demonstrated between verum rTMS and placebo conditions further supporting the notion of its antidepressant efficacy. Larger trials, however, which would be mandatory to substantiate the antidepressant efficacy of rTMS, have not been conducted to date. Therefore, efforts should be intensified to further investigate the efficacy of rTMS as antidepressant intervention and to test specific applications (e.g. primary treatment, augmentation, maintenance therapy) in the treatment of depressive episodes.

Key Words

Major Depression - Antidepressants - TMS - Mechanisms of Action - Clinical Trials

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