Effects of electroconvulsive therapy on cognitive functioning in patients with depression: protocol for a systematic review and meta-analysis

Abstract

IntroductionDepression is the leading cause of disability worldwide, affecting approximately 350 million people. Evidence indicates that only 60–70% of persons with major depressive disorder who tolerate antidepressants respond to first-line drug treatment; the remainder become treatment resistant. Electroconvulsive therapy (ECT) is considered an effective therapy in persons with treatment-resistant depression. The use of ECT is controversial due to concerns about temporary cognitive impairment in the acute post-treatment period. We will conduct a meta-analysis to examine the effects of ECT on cognition in persons with depression.MethodsThis systematic review and meta-analysis has been registered with PROSPERO (registration number: CRD42014009100). We developed our methods following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. We are searching MEDLINE, PsychINFO, EMBASE, CINAHL and Cochrane from the date of database inception to the end of October 2014. We are also searching the reference lists of published reviews and evidence reports for additional citations. Comparative studies (randomised controlled trials, cohort and case–control) published in English will be included in the meta-analysis. Three clinical neuropsychologists will group the cognitive tests in each included article into a set of mutually exclusive cognitive subdomains. The risk of bias of randomised controlled trials will be assessed using the Jadad scale. We will supplement the Jadad scale with additional questions based on the Cochrane risk of bias tool. The risk of bias of cohort and case–control studies will be assessed using the Newcastle-Ottawa Scale. We will employ the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to assess the strength of evidence.Statistical analysisSeparate meta-analyses will be conducted for each ECT treatment modality and cognitive subdomain using Comprehensive Meta-Analysis V.2.0.

Electroconvulsive therapy hasn't negative effects on short-term memory function, as assessed using a bedside hand-held device

“…In addition to the small sample size of our study and lack of a validation design, weaknesses of our study include the absence of groups of patients with particular risks, such as schizophrenic or geriatric (>65 years of age) patients, who are allegedly at a high risk of experiencing memory and concentration deficits due to ECT. 18,19,[35][36][37] Furthermore, participants with known neurocognitive deficits were not examined. The resilient findings for the group of middle-aged patients examined in this study, which included no observed effects of ECT on speed of processing contrast with the results of other investigations.…”

A Bayesian framework systematic review and meta-analysis of anesthetic agents effectiveness/tolerability profile in electroconvulsive therapy for major depression

“…It affects millions of people worldwide and is considered by the World Health Organization (WHO) to be one of the leading causes of disability 1 . Electroconvulsive therapy (ECT) is a well-established treatment for severe depressive episode 2 3 4 . Intravenous anesthetic medication before ECT is used to minimize subjective unpleasantness and adverse side effects of the induced tonic-clonic seizure.…”

Acetylcholinesterase inhibitors for electroconvulsive therapy‐induced cognitive side effects: a systematic review

“…Future studies in this field should therefore use a larger battery of neurocognitive measures in order to obtain full insight in cognitive functioning across various domains. Currently, the effect of electroconvulsive treatment in depressed patients on multiple cognitive subdomains (memory-immediate recall, verbal memory-delayed recall, verbal memory-recognition, nonverbal memory-immediate recall, non-verbal memorydelayed recall, non-verbal memory-recognition, working memory, attention, intellectual ability, executive function, processing speed, spatial problem solving, global cognitive status, language, motor, and construction/visuospatial) is being studied (Oremus et al, 2015).…”