Prediction of the antidepressant effects of ECT

Electroconvulsive therapy (ECT) is a brain stimulation method that is applied as an alternative, non- pharmacological treatment option for severe depressive disorder. It is mainly used when, despite long and intensive care, only insufficient response with antidepressants or psychotherapy can be achieved. ECT has been successfully used for over 80 years and there is vast scientific evidence demonstrating its efficacy. It is commonly assumed that mediated via neurotransmitters, hormones and neuronal growth factors ECT is accompanied by a regeneration of brain tissue and restores brain capacities that are disturbed by psychiatric disorders. However, the exact antidepressant mechanism underlying ECT remains to be fully understood and to date physicians are lacking a clinical tool enabling them to predict individual response to this elaborate treatment form. With the aim of identifying specific markers for ECT-response and to promote a better understanding of ECTs mechanism of action, 30 patients between 18 and 65 years of age suffering from a major depressive disorder and awaiting ECT will be examined in this prospective study over a period of five weeks. The participants will be treated with ECT twice weekly during their hospital stay lasting several weeks, overall at least eight times. At two time points, namely before the start and after the completion of ECT, extensive brain imaging using magnetic resonance imaging (M RI) will be performed in order to assess the influence of the treatment on brain structure, brain function and the communication between brain regions. Simultaneously, certain proteins that mirror neuronal growth, neuronal degradation and inflammatory processes in the brain, will be investigated in the spinal fluid (obtained by means of lumbar puncture) and the blood of the patients before and after ECT, respectively. Relations between these proteins, the observed changes in brain imaging as well as treatment response will be captured. Furthermore, the effect of ECT on mood and memory performance will be assessed using specific tests. The combination of brain imaging using M RI and biochemical markers in the spinal fluid within one study represents a unique approach in ECT research. The comprehensive characterization of the effects of ECT in regards to treatment response bears the potential of identifying specific hallmarks by which physicians will clarify in advance which patients will very likely benefit from ECT. M oreover, a better understanding of the mode of action of this therapeutic option and evidence showing that ECT does not lead to nerve damage will contribute to a destigmatization of this treatment method and promote a more frequent use of modern ECT.