Déficit cognitivo em crianças e adolescentes com transtorno bipolar em eutimia: revisão sistemática e meta-análise

Abstract

This work consists of a systematic review with meta-analysis of studies investigating neuropsychological functions in youth up to the age of 18 diagnosed with Bipolar Disorder (BD) in euthymic phase compared to healthy controls (HC). The study aims to to clarify the cognitive functioning of pediatric bipolar patients by investigating a representative sample and controlling potential sources of heterogeneity. A systematic search in the literature was performed in the Pubmed/MEDLINE, PsycInfo and EMBASE databases from inception until March 23rd, 2016 to select original peer-reviewed studies that investigated neuropsychological functions in youths diagnosed with TB in the euthymic phase compared to HC. Effect sizes were extracted for each of the neuropsychological tests used. In addition, the results were grouped according to the following cognitive domains: attention and vigilance, verbal learning, verbal memory, working memory, visual learning, visual memory, executive functions, processing speed and general cognition. The PRISMA Statement protocol was followed. The study synthesized data from twenty-four studies that met the inclusion criteria (N = 1146, 510 in the BD group and 636 in the control group). In general, euthymic bipolar youngsters had significant deficits in the domains of verbal learning, verbal memory, working memory, visual learning and visual memory with moderate to large effect sizes (Hedges’s g between 0.76 and 0.99). No significant deficits were observed in the domains of attention/vigilance, executive functions, and processing speed. The heterogeneity was moderate to large (I2 ≥ 50%) for most ES estimates. Differences in the definition of euthymia between the studies explained the heterogeneity in the ES estimation for verbal learning and memory. Evidence was also found for other potential sources of heterogeneity in various estimates of ES that included comorbidity with ADHD and anxiety disorders, as well as madication use. In addition, the use of different neuropsychological tests seemed to contribute to the heterogeneity of some estimates (e.g. in the attention/vigilance domain). At the end, it can be concluded that youths with euthymic BD present significant cognitive dysfunction encompassing the domains verbal learning, visual learning, verbal memory, visual memory and working memory. The results also suggest that, for a subset of individuals with BD, neurodevelopmental factors may contribute to cognitive dysfunction.