Studies naar prikkeldrempels bij elektroconvulsietherapie

Abstract

These studies examine a technical detail of electroconvulsive therapy (ECT), an effective and safe treatment for mood disorders and some other – sometimes life-threatening – illnesses. To become effective, a seizure has to be elicited by overcoming the brain’s seizure threshold (ST). Firstly, the literature was examined on (hypothetical) determinants of the ST. Secondly, a prospective observational study was conducted, showing higher age and bilateral electrode placement to be of predictive value for higher ST. Taking these variables also into account, an MRI study revealed that a higher volume of cerebrospinal fluid predicted a higher ST. Moreover, presence of psychotic depression and previous ECT predicted more positive outcome of ECT. Bipolar depression predicted less adverse cognitive effects, and using concomitant antipsychotics during the course of ECT predicted more adverse cognitive effects. Finally, more specific ECT patient groups were examined retrospectively, showing (among others) that malignant catatonic patients may recover better in case of those patients with more autonomic dysfunctions and when ECT was performed on a daily basis. Moreover, patients treated with continuation ECT showed longer duration of seizure activity, if the time-interval between ECT sessions was longer.