background Electroconvulsive therapy (ect) is an effective and safe treatment for depression and several other severe psychiatric conditions. In ect, the electrical stimulus must exceed the initial seizure threshold (ist) to elicit a generalized seizure. Seizure thresholds may vary substantially among patients and tend to raise during the course of ect. Several hypotheses have been described to explain the variety of initial seizure threshold (ist) levels in patients undergoing ect, but these were mostly neither examined extensively nor studied prospectively.
aim To report on an observational cohort study of all patients referred for ect to the Rijnstate Hospital, Arnhem.
methods Demographic, clinical, and brain morphological and functional variables were examined for their associations with ist, during the ect course, and as well as clinical effectiveness and cognitive side-effects. Levels of ist and every 6th ect-session were measured using an empirical titration method. Thickness of the skull and scalp, volumes of white matter hyperintensities, gray and white matter, and cerebrospinal fluid were calculated using structural magnetic resonance imaging (mri). With functional mri (fmri), resting state functional connectivity using blood oxygen level-dependent signals was examined. Effectiveness and side-effects of ect were assessed using, respectively, the MontgomeryÅsberg Depression Rating Scale and Mini-Mental State Examination at baseline and after index-ect.
results Data are now obtained (October 2010) and will be analysed using multiple variable regression analyses. This study may result in evidence for factors explaining the variety of ist and ist in patients undergoing ect.
conclusions Potentially promising next steps in research on non-invasive estimations of ist and clinical implications for future treatment techniques will be discussed.