Cognitive deficits associated with electroconvulsive therapy for depression: moderating factors and neuropsychological tests

Abstract

Due to the efficacy of electroconvulsive therapy (ECT) in the guideline-based treatment of therapy-resistant depressive episodes and the clinical significance of cognitive impairments, it is necessary to optimize the management of potential side effects. As cognitive side effects of the treatment combined with impairments resulting from the depression may lead to a reduction in the ability to function in social contexts and reduce subjective wellbeing, comprehensive information about and monitoring of potential side effects is essential. In this review we present the clinical relevance and measurement of cognitive side effects that may occur during electroconvulsive therapy. The individual characteristics of the patient as well as the technical and pharmacological parameters that influence the effect of ECT on cognition will be discussed. Furthermore, the recommendations of national and international treatment guidelines for the monitoring of cognitive side effects will be summarized.After ECT, impairments of global cognition, and anterograde as well as retrograde amnesia may occur. While the first two side effects appear to be transient, the extent of retrograde amnesia, particularly for autobiographical information, is not yet well understood and may potentially be present for a longer period. A controversial issue in this context is the question whether there are appropriate instruments for the monitoring of reduction in cognitive performance. In clinical context, a number of different measures are used, and in many cases, monitoring is omitted due to lack of time and methodological uncertainty. Current national and international guidelines make very different suggestions about the monitoring of cognitive side effects during ECT and in German-speaking regions no concrete recommendations are available. In this context, we recommend a revision of current guidelines and identify future areas of research that would further our understanding of the effects of ECT on cognition. These may enable us to keep an eye on these deficiencies better as well as allow us to identify patients that may have a higher risk of developing such impairments.