Altérations cognitives et plaintes mnésiques lors d’un traitement par électroconvulsivothérapie : revue de la littérature

RésuméL’électroconvulsivothérapie (ECT) est susceptible d’entraîner des altérations mnésiques, repérables à l’aide de tests neuropsychologiques « objectifs » et à l’origine de plaintes mnésiques « subjectives » rapportées par les sujets. Les études disponibles mettent en évidence des altérations mnésiques « objectives » à la suite d’un traitement par ECT variables selon les tests neuropsychologiques utilisés et la période d’évaluation par rapport aux séances ECT. Les méthodes d’évaluation des plaintes mnésiques « subjectives » et leurs résultats divergent également selon les études. L’objectif de cette revue de la littérature est de synthétiser les données disponibles concernant les altérations mnésiques « objectives » ainsi que les plaintes mnésiques « subjectives » rapportées à la suite d’un traitement par ECT et d’observer les relations entre ces deux types d’altérations mnésiques. Cette revue systématique de la littérature a permis de retenir 29 articles publiés de 1970 à 2012. Les seules altérations cognitives « objectives » persistantes à long terme après un traitement par ECT sont des altérations mnésiques rétrogrades autobiographiques. Les plaintes mnésiques concordent avec les altérations mnésiques objectives lorsqu’elles sont évaluées globalement, mais diffèrent lorsque les outils de mesure des plaintes subjectives utilisés demandent une évaluation plus spécifique.

ObjectivesElectroconvulsive treatment (ECT) is an efficient treatment of depression, mania or acute episode of schizophrenia. However, ECT can lead to several side effects, particularly regarding cognitive functioning. Neuropsychological tests show that memory impairment is the most common cognitive disturbance. Memory impairments are also self-reported by 29 % to 55 % of patients treated with ECT. The subjective perception of memory impairment belongs to the field of metacognition (or, in this case, metamemory). Metacognition is indeed defined as monitoring and control of its own cognitive processes, and can be evaluated during or after cognitive task (on line or off line). The subjective perception of memory impairment after ECT treatment has been scarcely explored in the literature. The aims of this review of the literature are to describe the “objectives” characteristics of memory impairment, the “subjective” characteristics of memory complaints observed after treatment with ECT, and the relationships that exist between objective and subjective memory impairment.MethodsThis review is based on a selection of articles identified using PubMed. Three exhaustive literature searches of Medline databases between years 1970 and 2012 were performed. The first search used the words “Electroconvulsive therapy” and “Anterograde Memory Loss” from the Medical Subject Headings or MESH (41 articles). The second search used the MESH words “Electroconvulsive therapy” and “Retrograde Amnesia” (103 articles). The third search used the MESH words “Electroconvulsive therapy” and the words “Subjective Memory” not listed in the MESH (29 articles). Titles and abstracts of literature review or meta-analysis in English and French were carefully screened. Regarding “objective” memory impairment, only studies comparing neuropsychological tests assessing memory conducted before and after treatment with curative ECT were selected. Regarding “subjective” memory impairment, only studies assessing memory complaints were selected. A selection of 29 relevant articles was carried out.ResultsThe only “objective” long-term cognitive impairment observed after treatment with ECT is retrograde autobiographical memory impairment. Anterograde memory performances (learning, episodic and visuospatial memory) are disrupted in the short-term period following ECT, but no longer several months later. Three self-administered questionnaires assessing “subjective” memory complaints are available: Cognitive Failure Questionnaire or CFQ (assessing perceived learning, attention and memory functions), Squire Subjective Memory Questionnaire or SSMQ (evaluating perceived specific memory functions) and Global Self-Evaluation-Memory or GSE-My (evaluating perceived global memory impairment). After ECT treatment, improvement in the CFQ scores and SSMQ (less memory complaints) is observed. However, scores at GSE-My are significantly lower after treatment, suggesting that subjects rate their global memory functioning as impaired by ECT. “Subjective” memory complaints are correlated with “objective” memory impairment, when complaints are globally assessed using the GSE-My.ConclusionThe fact that there is no long-term cognitive impairment after treatment with ECT is an important information that must be shared within the healthcare team and the patients in order to improve adhesion to ECT. Few studies have investigated subjective complaints, and no study has evaluated metacognitive skills during the cognitive task. It might be of interest to explore subjective memory changes after ECT by using on line metacognitive skills evaluation.