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Journal of the American Academy of... Apr 2017To perform a systematic review and meta-analysis of studies investigating neurocognition in euthymic youths with bipolar disorder (BD) compared to healthy controls (HCs). (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To perform a systematic review and meta-analysis of studies investigating neurocognition in euthymic youths with bipolar disorder (BD) compared to healthy controls (HCs).
METHOD
A systematic literature search was conducted in the PubMed/MEDLINE, PsycINFO, and EMBASE databases from inception up until March 23, 2016, for original peer-reviewed articles that investigated neurocognition in euthymic youths with BD compared to HCs. Effect sizes (ES) for individual tests were extracted. In addition, results were grouped according to cognitive domain. This review complied with the PRISMA statement guidelines.
RESULTS
A total of 24 studies met inclusion criteria (N = 1,146; 510 with BD). Overall, euthymic youths with BD were significantly impaired in verbal learning, verbal memory, working memory, visual learning, and visual memory, with moderate to large ESs (Hedge's g 0.76-0.99); significant impairments were not observed for attention/vigilance, reasoning and problem solving, and/or processing speed. Heterogeneity was moderate to large (I ≥ 50%) for most ES estimates. Differences in the definition of euthymia across studies explained the heterogeneity in the ES estimate for verbal learning and memory. We also found evidence for other potential sources of heterogeneity in several ES estimates including co-occurring attention-deficit/hyperactivity disorder (ADHD) and anxiety disorders, and the use of medications. In addition, the use of different neuropsychological tests appeared to contribute to heterogeneity of some estimates (e.g., attention/vigilance domain).
CONCLUSION
Euthymic youths with BD exhibit significant cognitive dysfunction encompassing verbal learning and memory, working memory, and/or visual learning and memory domains. These data indicate that for a subset of individuals with BD, neurodevelopmental factors may contribute to cognitive dysfunction.
Topics: Adolescent; Bipolar Disorder; Child; Cognitive Dysfunction; Comorbidity; Humans
PubMed: 28335872
DOI: 10.1016/j.jaac.2017.01.008 -
Neuroscience and Biobehavioral Reviews Oct 2016Neurocognitive deficits are present in bipolar disorder (BD) patients and their unaffected (nonbipolar) relatives, but it is not clear which domains are most often... (Review)
Review
BACKGROUND
Neurocognitive deficits are present in bipolar disorder (BD) patients and their unaffected (nonbipolar) relatives, but it is not clear which domains are most often impaired and the extent of the impairment resulting from shared genetic factors. In this literature review, we address these issues and identify specific neurocognitive tasks most sensitive to cognitive deficits in patients and unaffected relatives.
METHOD
We conducted a systematic review in Web of Science, PubMed/Medline and PsycINFO databases.
RESULTS
Fifty-one articles assessing cognitive functioning in BD patients (23 studies) and unaffected relatives (28 studies) were examined. Patients and, less so, relatives show impairments in attention, processing speed, verbal learning/memory, and verbal fluency.
CONCLUSION
Studies were more likely to find impairment in patients than relatives, suggesting that some neurocognitive deficits may be a result of the illness itself and/or its treatment. However, small sample sizes, differences among relatives studied (e.g., relatedness, diagnostic status, age), and differences in assessment instruments may contribute to inconsistencies in reported neurocognitive performance among relatives. Additional studies addressing these issues are needed.
Topics: Attention; Bipolar Disorder; Cognition; Cognition Disorders; Humans; Neuropsychological Tests
PubMed: 27502749
DOI: 10.1016/j.neubiorev.2016.08.002 -
Journal of Neurology Aug 2016We conducted a systematic review of the literature and used meta-analytic techniques to evaluate the impact of shunt surgery on neuropsychological performance in... (Meta-Analysis)
Meta-Analysis Review
We conducted a systematic review of the literature and used meta-analytic techniques to evaluate the impact of shunt surgery on neuropsychological performance in patients with normal pressure hydrocephalus (NPH). Twenty-three studies with 1059 patients were identified for review using PubMed, Web of Science, Google scholar and manual searching. Inclusion criteria were prospective, within-subject investigations of cognitive outcome using neuropsychological assessment before and after shunt surgery in patients with NPH. There were statistically significant effects of shunt surgery on cognition (Mini-Mental State Examination; MMSE), learning and memory (Rey Auditory Verbal Learning Test; RAVLT, total and delayed subtests), executive function (backwards digit span, phonemic verbal fluency, trail making test B) and psychomotor speed (trail making test A) all in the direction of improvement following shunt surgery, but with considerable heterogeneity across all measures. A more detailed examination of the data suggested robust evidence for improved MMSE, RAVLT total, RAVLT delayed, phonemic verbal fluency and trail making test A only. Meta-regressions revealed no statistically significant effect of age, sex or follow-up interval on improvement in the MMSE. Our results suggest that shunt surgery is most sensitive for improving global cognition, learning and memory and psychomotor speed in patients with NPH.
Topics: Cerebrospinal Fluid Shunts; Cognition Disorders; Databases, Bibliographic; Humans; Hydrocephalus, Normal Pressure; Neuropsychological Tests
PubMed: 27017344
DOI: 10.1007/s00415-016-8097-0 -
The Clinical Neuropsychologist 2016Several social life events and challenges have an impact on cognitive development. Our goal was to analyze the predictors of change in cognitive performance in early... (Review)
Review
OBJECTIVE
Several social life events and challenges have an impact on cognitive development. Our goal was to analyze the predictors of change in cognitive performance in early midlife in a general population sample. Additionally, systematic literature review was performed.
METHOD
The study sample was drawn from the Northern Finland Birth Cohort 1966 at the ages of 34 and 43 years. Primary school performance, sociodemographic factors and body mass index (BMI) were used to predict change in cognitive performance measured by the California Verbal Learning Test, Visual Object Learning Test, and Abstraction Inhibition and Working Memory task. Analyses were weighted by gender and education, and p-values were corrected for multiple comparisons using Benjamini-Hochberg procedure (B-H).
RESULTS
Male gender predicted decrease in episodic memory. Poor school marks of practical subjects, having no children, and increase in BMI were associated with decrease in episodic memory, though non-significantly after B-H. Better school marks, and higher occupational class were associated with preserved performance in visual object learning. Higher vocational education predicted preserved performance in visual object learning test, though non-significantly after B-H. Likewise, having children predicted decreased performance in executive functioning but non-significantly after B-H.
CONCLUSIONS
Adolescent cognitive ability, change in BMI and several sociodemographic factors appear to predict cognitive changes in early midlife. The key advantage of present study is the exploration of possible predictors of change in cognitive performance among general population in the early midlife, a developmental period that has been earlier overlooked.
Topics: Adult; Body Mass Index; Cognition; Executive Function; Female; Finland; Humans; Learning; Male; Memory, Short-Term; Neuropsychological Tests; Sex Factors; Socioeconomic Factors
PubMed: 26734714
DOI: 10.1080/13854046.2015.1128000 -
Acta Neurochirurgica Jan 2016Cognitive preservation is crucial in glioma surgery, as it is an important aspect of daily life functioning. Several studies claimed that surgery in eloquent areas is... (Review)
Review
BACKGROUND
Cognitive preservation is crucial in glioma surgery, as it is an important aspect of daily life functioning. Several studies claimed that surgery in eloquent areas is possible without causing severe cognitive damage. However, this conclusion was relatively ungrounded due to the lack of extensive neuropsychological testing in homogenous patient groups. In this study, we aimed to elucidate the short-term and long-term effects of glioma surgery on cognition by identifying all studies who conducted neuropsychological tests preoperatively and postoperatively in glioma patients.
METHODS
We systematically searched the electronical databases Embase, Medline OvidSP, Web of Science, PsychINFO OvidSP, PubMed, Cochrane, Google Scholar, Scirius and Proquest aimed at cognitive performance in glioma patients preoperatively and postoperatively.
RESULTS
We included 17 studies with tests assessing the cognitive domains: language, memory, attention, executive functions and/or visuospatial abilities. Language was the domain most frequently examined. Immediately postoperatively, all studies except one, found deterioration in one or more cognitive domains. In the longer term (3-6/6-12 months postoperatively), the following tests showed both recovery and deterioration compared with the preoperative level: naming and verbal fluency (language), verbal word learning (memory) and Trailmaking B (executive functions).
CONCLUSIONS
Cognitive recovery to the preoperative level after surgery is possible to a certain extent; however, the results are too arbitrary to draw definite conclusions and not all studies investigated all cognitive domains. More studies with longer postoperative follow-up with tests for cognitive change are necessary for a better understanding of the conclusive effects of glioma surgery on cognition.
Topics: Adult; Brain Neoplasms; Child; Cognition; Cognition Disorders; Glioma; Humans; Neuropsychological Tests; Postoperative Complications; Treatment Outcome
PubMed: 26566782
DOI: 10.1007/s00701-015-2601-7 -
CoDAS 2015This review aimed at presenting the benefits regarding the speech perception in noise shown by children who wear hearing aid devices and/or cochlear implants with the... (Review)
Review
PURPOSE
This review aimed at presenting the benefits regarding the speech perception in noise shown by children who wear hearing aid devices and/or cochlear implants with the Frequency Modulation (FM) System at school.
RESEARCH STRATEGY
A bibliographic survey was conducted in an electronic database with standardized search until the year 2012, and a manual search was performed by using specific keywords.
SELECTION CRITERIA
For the selection and evaluation of the scientific studies chosen in the search, criteria were established covering the following aspects: type of study, participants, adopted intervention, and evaluation of results.
DATA ANALYSIS
The FM system was verified to improve speech perception and speech threshold in noise in all studies.
RESULTS
Regarding the performance as to type, the best results were obtained when children used the personal FM system, followed by the table and the sound field systems.
CONCLUSION
After extensive review of national and international literature, it was concluded that the studies indicate the need for further research concerning mainly the impact of the FM system on the school performance of children who have sensory devices coupled to the FM system. Findings in the literature with relation to the publications focused on speech perception in noise did not relate educational and auditory aspects.
Topics: Child; Cochlear Implantation; Cochlear Implants; Hearing Aids; Hearing Loss, Sensorineural; Humans; Speech Perception; Verbal Learning
PubMed: 26222948
DOI: 10.1590/2317-1782/20152014103 -
Association between myasthenia gravis and cognitive function: A systematic review and meta-analysis.Annals of Indian Academy of Neurology 2015The course of myasthenia gravis (MG) is complicated by increased reports of cognitive defects in both human and animal models, which suggests potential central nervous... (Review)
Review
The course of myasthenia gravis (MG) is complicated by increased reports of cognitive defects in both human and animal models, which suggests potential central nervous system (CNS) damage. We conducted a systematic review of the relationships between MG and cognitive function. This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Major databases were searched to examine the neuropsychological studies of adults with MG. Weighted effect sizes were pooled by cognitive domain. Eight studies representing 300 subjects were included. Eight cognitive domain categories were identified: (i) Mini-Mental State Examination (MMSE), (ii) language, (iii) processing speed, (iv) verbal learning and memory, (v) visual learning and memory, (vi) attention span, (vii) response fluency, and (viii) motor performance. Nine (cognitive domain categories, MMSE, language, processing speed, verbal learning and memory (except for delayed recall memory), and motor performance) of 16 cognitive tasks revealed significant moderate effect sizes. Verbal logical-delayed memory, finger tapping with the preferred hand, and the Symbol Digit Modalities Test showed a greater magnitude relationship to cognitive function than did other specific cognitive domains. Verbal learning and memory seems to be the most significant affected according to cognitive domain categories. For MG, the ability of attention, response fluency, visual learning, and memory seems to be reserved. The MG patients seem to perform significantly worse than the non-MG controls in a range of cognitive domains. Our findings should be interpreted with caution because of the clinical and methodological heterogeneity of included studies.
PubMed: 26019407
DOI: 10.4103/0972-2327.156560 -
The Cochrane Database of Systematic... May 2015People with fragile X syndrome (FXS) have an intellectual dysfunction that can range from very mild to severe. Symptoms can include speech and language delays and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
People with fragile X syndrome (FXS) have an intellectual dysfunction that can range from very mild to severe. Symptoms can include speech and language delays and behavioural difficulties such as aggression or self injurious behaviours, emotional lability, and anxiety-related problems (for example obsessive-compulsive symptoms and perseverative behaviours). In some cases, affected people may have an additional diagnosis of attention deficit hyperactivity disorder or an autism spectrum disorder.
OBJECTIVES
To review the efficacy and safety of L-acetylcarnitine in improving the psychological, intellectual, and social performance of people with FXS.
SEARCH METHODS
In May 2015 we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO, Web of Science, and two other databases. We also searched three trials registers, four theses databases, and the reference lists of relevant studies and reviews.
SELECTION CRITERIA
Randomised controlled trials (RCTs) that assessed the efficacy of L-acetylcarnitine, at any dose, in people of any age diagnosed with FXS compared with placebo.
DATA COLLECTION AND ANALYSIS
For each trial, two review authors independently extracted data on the children included and interventions compared, and assessed the risk of bias of the studies across the following domains: randomisation sequence generation, allocation concealment, blinding (of participants, personnel, and outcome assessors), incomplete outcome data, selective outcome reporting, and other potential sources of bias.
MAIN RESULTS
We found only two RCTs that compared oral L-acetylcarnitine (LAC) with oral placebo in children with FXS. The studies included a total of 83 participants, all of them male, who were treated and followed for one year. The age of participants at the start of treatment ranged from 6 to 13 years, with a mean age of 9 years. Neither study provided information on randomisation, allocation concealment procedures, or blinding of outcome assessment, and we received no responses from the authors we emailed for clarification. We therefore rated studies as being at unclear risk of bias on these domains. We judged both studies to be at low risk of bias for blinding of participants and personnel, incomplete outcome data, and selective reporting, but to be at high risk of other bias, as at least one study was funded by a drug company, and in both studies people working for the company were part of the research team.We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to rate the quality of the available evidence. Overall, the quality of the evidence was low due to the imprecision of results and high risk of other bias.Regarding the primary outcome of psychological and learning capabilities, both studies assessed the effect of interventions on children's verbal and non-verbal intellectual functioning using the Wechsler Intelligence Scale for Children - Revised. The authors did not provide detailed data on those results but said that they found no important differences between treatment and placebo.Both studies evaluated the impact of the treatment on hyperactive behaviour using the Conners' Abbreviated Parent-Teacher Questionnaire. In one study, teachers' assessments of the children found no clear evidence of a difference (mean difference (MD) 0.50, 95% confidence interval (CI) -5.08 to 6.08, n = 51; low-quality evidence). The other study stated that there were no differences between treated and untreated participants, but did not provide detailed data for inclusion in the meta-analysis.Parents' assessments favoured LAC in one study (MD -0.57, 95% CI -0.94 to -0.19, n = 17; low-quality evidence), but not in the other (MD -2.80, 95% CI -7.61 to 2.01, n = 51; low-quality evidence), though changes were not large enough to be considered clinically relevant.Regarding social skills, one study reported no clear evidence of a difference in Vineland Adaptive Behavior composite scores (MD 8.20, 95% CI -0.02 to 16.42, n = 51; low-quality evidence), yet results in the socialisation domain favoured LAC (MD 11.30, 95% CI 2.52 to 20.08, n = 51; low-quality evidence).Both studies assessed the safety of the active treatment and recorded no side effects. Neither of the included studies assessed the secondary outcome of caregiver burden.
AUTHORS' CONCLUSIONS
Low-quality evidence from two small trials showed that when compared to placebo, LAC may not improve intellectual functioning or hyperactive behaviour in children with FXS.
Topics: Acetylcarnitine; Administration, Oral; Adolescent; Attention Deficit Disorder with Hyperactivity; Child; Fragile X Syndrome; Humans; Male; Randomized Controlled Trials as Topic; Vitamin B Complex
PubMed: 25985235
DOI: 10.1002/14651858.CD010012.pub2 -
Jornal Brasileiro de Pneumologia :... 2015The objectives of this study were to characterize and clarify the relationships between the various cognitive domains affected in COPD patients and the disease itself,... (Review)
Review
The objectives of this study were to characterize and clarify the relationships between the various cognitive domains affected in COPD patients and the disease itself, as well as to determine the prevalence of impairment in the various cognitive domains in such patients. To that end, we performed a systematic review using the following databases: PubMed, Scopus, and ScienceDirect. We included articles that provided information on cognitive impairment in COPD patients. The review of the findings of the articles showed a significant relationship between COPD and cognitive impairment. The most widely studied cognitive domains are memory and attention. Verbal memory and learning constitute the second most commonly impaired cognitive domain in patients with COPD. The prevalence of impairment in visuospatial memory and intermediate visual memory is 26.9% and 19.2%, respectively. We found that cognitive impairment is associated with the profile of COPD severity and its comorbidities. The articles reviewed demonstrated that there is considerable impairment of the cognitive domains memory and attention in patients with COPD. Future studies should address impairments in different cognitive domains according to the disease stage in patients with COPD.
Topics: Cognition Disorders; Cross-Sectional Studies; Female; Humans; Learning Disabilities; Male; Memory Disorders; Neuropsychological Tests; Observational Studies as Topic; Pulmonary Disease, Chronic Obstructive
PubMed: 25909154
DOI: 10.1590/S1806-37132015000004424 -
PloS One 2015Many common disorders across the lifespan feature impaired working memory (WM). Reported benefits of a WM training program include improving inattention in daily life,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Many common disorders across the lifespan feature impaired working memory (WM). Reported benefits of a WM training program include improving inattention in daily life, but this has not been evaluated in a meta-analysis. This study aimed to evaluate whether one WM training method has benefits for inattention in daily life by conducting a systematic review and meta-analysis.
METHODS
We searched Medline and PsycINFO, relevant journals and contacted authors for studies with an intervention and control group reporting post-training estimates of inattention in daily life. To reduce the influence of different WM training methods on the findings, the review was restricted to trials evaluating the Cogmed method. A meta-analysis calculated the pooled standardised difference in means (SMD) between intervention and control groups.
RESULTS
A total of 622 studies were identified and 12 studies with 13 group comparisons met inclusion criteria. The meta-analysis showed a significant training effect on inattention in daily life, SMD=-0.47, 95% CI -0.65, -0.29, p<.00001. Subgroup analyses showed this significant effect was observed in groups of children and adults as well as users with and without ADHD, and in studies using control groups that were active and non-adaptive, wait-list and passive as well as studies using specific or general measures. Seven of the studies reported follow-up assessment and a meta-analysis showed persisting training benefits for inattention in daily life, SMD=-0.33, 95% CI -0.57 -0.09, p=.006. Additional meta-analyses confirmed improvements after training on visuospatial WM, SMD=0.66, 95% CI 0.43, 0.89, p<.00001, and verbal WM tasks, SMD=0.40, 95% CI 0.18, 0.62, p=.0004.
CONCLUSIONS
Benefits of a WM training program generalise to improvements in everyday functioning. Initial evidence shows that the Cogmed method has significant benefits for inattention in daily life with a clinically relevant effect size.
Topics: Activities of Daily Living; Attention; Humans; Learning; Memory, Short-Term
PubMed: 25793607
DOI: 10.1371/journal.pone.0119522