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Heliyon Sep 2023Hearing loss has been reported as the most significant modifiable risk factor for dementia, but it is still unknown whether auditory rehabilitation can practically...
BACKGROUND
Hearing loss has been reported as the most significant modifiable risk factor for dementia, but it is still unknown whether auditory rehabilitation can practically prevent cognitive decline. We aim to systematically analyze the longitudinal effects of auditory rehabilitation via cochlear implants (CIs).
METHODS
In this systematic review and meta-analysis, we searched relevant literature published from January 1, 2000 to April 30, 2022, using electronic databases, and selected studies in which CIs were performed mainly on older adults and follow-up assessments were conducted in both domains: speech perception and cognitive function. A random-effects meta-analysis was conducted for each domain and for each timepoint comparison (pre-CI vs. six months post-CI; six months post-CI vs. 12 months post-CI; pre-CI vs. 12 months post-CI), and heterogeneity was assessed using Cochran's Q test.
FINDINGS
Of the 1918 retrieved articles, 20 research papers (648 CI subjects) were included. The results demonstrated that speech perception was rapidly enhanced after CI, whereas cognitive function had different speeds of improvement for different subtypes: executive function steadily improved significantly up to 12 months post-CI (g = 0.281, < 0.001; g = 0.115, = 0.003; g = 0.260, < 0.001 in the order of timepoint comparison); verbal memory was significantly enhanced at six months post-CI and was maintained until 12 months post-CI (g = 0.296, = 0.002; g = 0.095, = 0.427; g = 0.401, < 0.001); non-verbal memory showed no considerable progress at six months post-CI, but significant improvement at 12 months post-CI (g = -0.053, = 0.723; g = 0.112, = 0.089; g = 0.214, = 0.023).
INTERPRETATION
The outcomes demonstrate that auditory rehabilitation via CIs could have a long-term positive impact on cognitive abilities. Given that older adults' cognitive abilities are on the trajectory of progressive decline with age, these results highlight the need to increase the adoption of CIs among this population.
PubMed: 37809368
DOI: 10.1016/j.heliyon.2023.e19703 -
Frontiers in Neurology 2023Web-based rehabilitation, a branch of telerehabilitation, is carried out over the internet, unrestricted by time or place. Even though web-based interventions have been...
OBJECTIVE
Web-based rehabilitation, a branch of telerehabilitation, is carried out over the internet, unrestricted by time or place. Even though web-based interventions have been reported as feasible and effective in cases of mood disorders, for example, such evidence on the effectiveness of web-based cognitive rehabilitation remains unclear. This systematic review summarizes current knowledge on web-based psychoeducational programs aiming to manage cognitive deficits in patients with diseases that affect cognition.
METHODS
Using the Ovid database and the Web of Science, we systematically searched the Cochrane Database of Systematic Reviews, Medline, and PsycINFO to identify eligible studies. The review protocol (CRD42021257315) was pre-registered with the PROSPERO International Prospective Register of Systematic Reviews. The search was performed 10/13/2022. Two reviewers independently screened titles, abstracts, and full-texts, and extracted data for the selected studies. Two independent reviewers assessed the methodological quality.
RESULTS
The search retrieved 6,487 articles. Four studies with different patient groups (stroke, traumatic brain injury, brain tumor, and cancer) met the inclusion criteria of this systematic review. The studies examined systematic cognition-focused psychoeducational rehabilitation programs in which the patient worked independently. Three studies found positive effects on subjective cognitive functions, executive functions, and self-reported memory. No effects were found on objective cognitive functions. However, the studies had methodological weaknesses (non-randomized designs, small sample sizes, vaguely described interventions). Overall, adherence and patient satisfaction were good/excellent.
CONCLUSION
Web-based cognitive intervention programs are a new approach to rehabilitation and patient education. The evidence, although scarce, shows that web-based interventions are feasible and support subjective cognitive functioning. However, the literature to date is extremely limited and the quality of the studies is weak. More research with high-quality study designs is needed.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=257315, identifier: CRD42021257315.
PubMed: 37780726
DOI: 10.3389/fneur.2023.1249995 -
Neuropsychology Review Sep 2023The current diagnostic criteria for the behavioural variant of frontotemporal dementia (bvFTD) foresee a relative sparing of long-term memory. Although bvFTD patients... (Review)
Review
Genuine Memory Deficits as Assessed by the Free and Cued Selective Reminding Test (FCSRT) in the Behavioural Variant of Frontotemporal Dementia. A Systematic Review and Meta-analysis Study.
The current diagnostic criteria for the behavioural variant of frontotemporal dementia (bvFTD) foresee a relative sparing of long-term memory. Although bvFTD patients were thought to report secondary memory deficits associated with prefrontal dysfunctions, some studies indicated the presence of a "genuine memory deficit" related to mesial temporal lobe dysfunctions. Among various neuropsychological tests, the Free and Cue Selective Reminding Test (FCSRT) has been recommended to distinguish genuine from apparent amnesia. We conducted a systematic review and a random effect Bayesian meta-analysis to evaluate the nature and severity of memory deficit in bvFTD. Our objective was to determine whether the existing literature offers evidence of genuine or apparent amnesia in patients with bvFTD, as assessed via the FCSRT. On 06/19/2021, we conducted a search across four databases (PMC, Scopus, Web of Science, and PubMed). We included all studies that evaluated memory performance using the FCSRT in patients with bvFTD, as long as they also included either cognitively unimpaired participants or AD groups. We tested publication bias through the Funnel plot and Egger's test. To assess the quality of studies, we used the Newcastle-Ottawa quality assessment scale adapted for cross-sectional studies. We included 16 studies in the meta-analysis. The results showed that bvFTD patients perform better than AD patients (pooled effects between 0.95 and 1.14), as their memory performance stands between AD and control groups (pooled effects between - 2.19 and - 1.25). Moreover, patients with bvFTD present both genuine and secondary memory disorders. As a major limitation of this study, due to our adoption of a rigorous methodology and stringent inclusion criteria, we ended up with just 16 studies. Nonetheless, our robust findings can contribute to the ongoing discussion on international consensus criteria for bvFTD and the selection of appropriate neuropsychological tools to facilitate the differential diagnosis between AD and bvFTD.
PubMed: 37736861
DOI: 10.1007/s11065-023-09613-3 -
Journal of Integrative Neuroscience Sep 2023Patients with post-stroke memory disorder (PSMD) have poor quality of life and it is necessary to identify more beneficial stimulation protocols for treatment with... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Patients with post-stroke memory disorder (PSMD) have poor quality of life and it is necessary to identify more beneficial stimulation protocols for treatment with repetitive transcranial magnetic stimulation (rTMS). This meta-analysis was conducted to investigate the efficacy and safety of rTMS for improving memory performance, global cognition, and activities of daily living (ADL) among patients with PSMD.
METHODS
The PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang databases were screened to identify relevant randomized controlled trials. The primary outcome was memory performance; secondary outcomes included global cognition, ADL, and adverse events. STATA software was used to perform data synthesis.
RESULTS
Five articles with a total of 192 participants were included. The results indicated that rTMS was superior to control treatments for improving memory performance (mean difference [MD] = 1.73, 95% CI [Confidence Interval] [0.85, 2.60], 0.001), global cognition (MD = 2.44, 95% CI [0.96, 3.93], 0.001), and ADL (MD = 10.29, 95% CI [5.10, 15.48], 0.001). No significant differences were found between the low-frequency (LF) and high-frequency (HF) rTMS subgroups ( 0.47, = 0.00%) or between the sham rTMS and non-rTMS subgroups ( 0.94, = 0.00%). Four studies did not reported adverse events.
CONCLUSIONS
rTMS may improve memory function, global cognition, and the ability to perform ADL in patients with PSMD. LF-rTMS and HF-rTMS may have equal efficacy for treatment of PSMD. Future studies should consider extending the follow-up period to explore the safety and long-term efficacy of rTMS for treatment of PSMD and the appropriate choice of placebo for clinical trials of this treatment.
Topics: Humans; Transcranial Magnetic Stimulation; Activities of Daily Living; Quality of Life; Memory Disorders; Memory; Stroke
PubMed: 37735134
DOI: 10.31083/j.jin2205131 -
Schizophrenia Research. Cognition Dec 2023In a previous meta-analysis, the use of serotonin(5-HT) receptor partial agonists of the azapirone class as an add-on therapy was associated with beneficial effects on...
BACKGROUND
In a previous meta-analysis, the use of serotonin(5-HT) receptor partial agonists of the azapirone class as an add-on therapy was associated with beneficial effects on positive symptoms and attention/processing speed in schizophrenia patients. This meta-analysis builds on that study by examining the effects of adjunctive treatment with 5-HT partial agonists in improving other domains of neurocognitive function in schizophrenia patients.
METHODS
A literature search was performed from 1987 to May 2023 to identify randomized controlled trials. The standardized mean difference (SMD) with 95 % confidence intervals (CI) was calculated when there were two or more studies. Four studies, involving 313 patients, met the inclusion criteria and were used in the analysis.
RESULTS
5-HT partial agonists (buspirone or tandospirone) did not have a significant effect on verbal learning (SMD = 0.08, 95 % CI = -0.31 to 0.47) or working memory (SMD = 0.15, 95 % CI = -0.09 to 0.39). Regarding executive functions (Wisconsin Card Sorting Test), positive but non-significant results were seen with the category number (SMD = 0.26, 95 % CI = -0.81 to 1.32), while non-significant effects were noted for percent preservation errors (SMD = -0.10, 95 % CI = -0.53 to 0.33).
CONCLUSIONS
The absence of any significant benefits in the cognitive domains studied here may have been due to the variance in the concomitant medication (typical vs atypical antipsychotic drugs), the level of cognition at baseline, or other factors. Further studies with various types of 5-HT agonists are warranted to examine the potential cognitive efficacy of stimulating these receptors.
PubMed: 37732133
DOI: 10.1016/j.scog.2023.100290 -
JAMA Network Open Sep 2023The utility of antihypertensives and ideal blood pressure (BP) for dementia prevention in late life remains unclear and highly contested. (Meta-Analysis)
Meta-Analysis
IMPORTANCE
The utility of antihypertensives and ideal blood pressure (BP) for dementia prevention in late life remains unclear and highly contested.
OBJECTIVES
To assess the associations of hypertension history, antihypertensive use, and baseline measured BP in late life (age >60 years) with dementia and the moderating factors of age, sex, and racial group.
DATA SOURCE AND STUDY SELECTION
Longitudinal, population-based studies of aging participating in the Cohort Studies of Memory in an International Consortium (COSMIC) group were included. Participants were individuals without dementia at baseline aged 60 to 110 years and were based in 15 different countries (US, Brazil, Australia, China, Korea, Singapore, Central African Republic, Republic of Congo, Nigeria, Germany, Spain, Italy, France, Sweden, and Greece).
DATA EXTRACTION AND SYNTHESIS
Participants were grouped in 3 categories based on previous diagnosis of hypertension and baseline antihypertensive use: healthy controls, treated hypertension, and untreated hypertension. Baseline systolic BP (SBP) and diastolic BP (DBP) were treated as continuous variables. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-Analyses of Individual Participant Data reporting guidelines.
MAIN OUTCOMES AND MEASURES
The key outcome was all-cause dementia. Mixed-effects Cox proportional hazards models were used to assess the associations between the exposures and the key outcome variable. The association between dementia and baseline BP was modeled using nonlinear natural splines. The main analysis was a partially adjusted Cox proportional hazards model controlling for age, age squared, sex, education, racial group, and a random effect for study. Sensitivity analyses included a fully adjusted analysis, a restricted analysis of those individuals with more than 5 years of follow-up data, and models examining the moderating factors of age, sex, and racial group.
RESULTS
The analysis included 17 studies with 34 519 community dwelling older adults (20 160 [58.4%] female) with a mean (SD) age of 72.5 (7.5) years and a mean (SD) follow-up of 4.3 (4.3) years. In the main, partially adjusted analysis including 14 studies, individuals with untreated hypertension had a 42% increased risk of dementia compared with healthy controls (hazard ratio [HR], 1.42; 95% CI 1.15-1.76; P = .001) and 26% increased risk compared with individuals with treated hypertension (HR, 1.26; 95% CI, 1.03-1.53; P = .02). Individuals with treated hypertension had no significant increased dementia risk compared with healthy controls (HR, 1.13; 95% CI, 0.99-1.28; P = .07). The association of antihypertensive use or hypertension status with dementia did not vary with baseline BP. There was no significant association of baseline SBP or DBP with dementia risk in any of the analyses. There were no significant interactions with age, sex, or racial group for any of the analyses.
CONCLUSIONS AND RELEVANCE
This individual patient data meta-analysis of longitudinal cohort studies found that antihypertensive use was associated with decreased dementia risk compared with individuals with untreated hypertension through all ages in late life. Individuals with treated hypertension had no increased risk of dementia compared with healthy controls.
Topics: Humans; Female; Aged; Male; Blood Pressure; Antihypertensive Agents; Longitudinal Studies; Hypertension; Dementia
PubMed: 37698858
DOI: 10.1001/jamanetworkopen.2023.33353 -
Journal of Affective Disorders Dec 2023Depression is highly prevalent in low- and middle- income countries (LMIC) and associated with significant cognitive dysfunction across multiple domains. However, little... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Depression is highly prevalent in low- and middle- income countries (LMIC) and associated with significant cognitive dysfunction across multiple domains. However, little is known about neurocognitive tests used in people with depression in LMIC. We aimed to investigate cognitive performance and cognitive tests in depression research in LMIC.
METHODS
APA PsycInfo, Embase, Ovid MEDLINE, and Global Health were systematically searched for studies that implemented a cognitive performance test in a depressed, LMIC population. Tool quality was assessed using an adapted scale for quality of measures in cross-cultural settings. Data extracted included demographics, depression and cognitive performance measures, and cognitive performance comparisons between depression and control groups.
RESULTS
29 studies met eligibility criteria, involving a total of 19,100 participants from 11 LMIC. 93.1 % of studies were conducted in upper middle-income countries. 67 cognitive performance tools were implemented. Reliability was reported for 5.6 % of cognitive performance tests and validity was reported for 8.3 %. 36.1 % of tests used were culturally adapted. 75.9 % of included studies implemented at least one memory test. Cognitive deficits were observed in all depressed groups, especially in memory (Cohen's d = -1.60, 95 % CI -2.02 to -1.18).
LIMITATIONS
Heterogeneity between studies; averaged results across memory subtypes; no assessment of depression severity and cognitive deficits associations; restrictive search terms.
CONCLUSIONS
Cognitive impairments in depression, especially in memory, are prevalent in LMIC. This research has drawn attention to the burden of cognitive dysfunction in depression in LMIC, and to the disparate research gap in LMIC. PROSPERO registration CRD42022315397.
Topics: Humans; Developing Countries; Depression; Reproducibility of Results; Poverty; Cognition
PubMed: 37690541
DOI: 10.1016/j.jad.2023.09.007 -
Journal of Alzheimer's Disease : JAD 2023Alzheimer's disease (AD) is a prevalent neurodegenerative disorder without a cure. Innovative disease models, such as induced neurons (iNs), could enhance our...
BACKGROUND
Alzheimer's disease (AD) is a prevalent neurodegenerative disorder without a cure. Innovative disease models, such as induced neurons (iNs), could enhance our understanding of AD mechanisms and accelerate treatment development. However, a review of AD human iN studies is necessary to consolidate knowledge.
OBJECTIVE
The objective of this review is to examine the current body of literature on AD human iN cells and provide an overview of the findings to date.
METHODS
We searched two databases for relevant studies published between 2010 and 2023, identifying nine studies meeting our criteria.
RESULTS
Reviewed studies indicate the feasibility of generating iNs directly from AD patients' fibroblasts using chemical induction or viral vectors. These cells express mature neuronal markers, including MAP-2, NeuN, synapsin, and tau. However, most studies were limited in sample size and primarily focused on autosomal dominant familial AD (FAD) rather than the more common sporadic forms of AD. Several studies indicated that iNs derived from FAD fibroblasts exhibited abnormal amyloid-β metabolism, a characteristic feature of AD in humans. Additionally, elevated levels of hyperphosphorylated tau, another hallmark of AD, were reported in some studies.
CONCLUSION
Although only a limited number of small-scale studies are currently available, AD patient-derived iNs hold promise as a valuable model for investigating AD pathogenesis. Future research should aim to conduct larger studies, particularly focusing on sporadic AD cases, to enhance the clinical relevance of the findings for the broader AD patient population. Moreover, these cells can be utilized in screening potential novel treatments for AD.
Topics: Humans; Alzheimer Disease; Amyloid beta-Peptides; tau Proteins; Neurons; Fibroblasts
PubMed: 37661882
DOI: 10.3233/JAD-230119 -
Behavioural Brain Research Oct 2023The modified multi-platform method (MMPM) is used to induce animal models of paradoxical sleep deprivation and impairs memory in rodents. However, variations in MMPM... (Meta-Analysis)
Meta-Analysis Review
The modified multi-platform method (MMPM) is used to induce animal models of paradoxical sleep deprivation and impairs memory in rodents. However, variations in MMPM protocols have contributed to inconsistent conclusions across studies. This meta-analysis aimed to assess the variations of the MMPM and their effects on memory in rats and mice. A comprehensive search identified 60 studies, and 50 were included in our meta-analysis. Overall, the meta-analysis showed that the MMPM significantly reduced the percentage of time spent in target quadrants (I = 54 %, 95 % confidence interval [CI] = [-1.83, -1.18]) and the number of platform-area crossings (I = 26 %, 95 % CI = [-1.71, -1.07]) in the Morris water maze (MWM) and shortened the latency to entering the dark compartment in the passive avoidance task (I = 68 %, 95 % CI = [-1.36, -0.57]), but it increased the number of errors in the radial arm water maze (RAWM) (I = 59 %, 95 % CI = [1.29, 2.07]). Additionally, mice performed worse on the MWM, whereas rats performed worse on the passive avoidance task. More significant memory deficits were found in cross-learning and post-learning MMPM in the MWM and RAWM, respectively. This study provided evidence that the MMPM can be used in preclinical studies of memory deficits induced by paradoxical sleep deprivation.
Topics: Mice; Rats; Animals; Sleep Deprivation; Learning; Memory Disorders; Methacrylates
PubMed: 37652237
DOI: 10.1016/j.bbr.2023.114652 -
Brain Sciences Aug 2023Fear is characterized by distinct behavioral and physiological responses that are essential for the survival of the human species. Fear conditioning (FC) serves as a... (Review)
Review
Fear is characterized by distinct behavioral and physiological responses that are essential for the survival of the human species. Fear conditioning (FC) serves as a valuable model for studying the acquisition, extinction, and expression of fear. The serotonin (5-hydroxytryptamine, 5-HT) system is known to play a significant role in emotional and motivational aspects of human behavior, including fear learning and expression. Accumulating evidence from both animal and human studies suggests that brain regions involved in FC, such as the amygdala, hippocampus, and prefrontal cortex, possess a high density of 5-HT receptors, implicating the crucial involvement of serotonin in aversive learning. Additionally, studies exploring serotonin gene polymorphisms have indicated their potential influence on FC. Therefore, the objective of this work was to review the existing evidence linking 5-HT with fear learning and memory in humans. Through a comprehensive screening of the PubMed and Web of Science databases, 29 relevant studies were included in the final review. These studies investigated the relationship between serotonin and fear learning using drug manipulations or by studying 5-HT-related gene polymorphisms. The results suggest that elevated levels of 5-HT enhance aversive learning, indicating that the modulation of serotonin 5-HT2A receptors regulates the expression of fear responses in humans. Understanding the role of this neurochemical messenger in associative aversive learning can provide insights into psychiatric disorders such as anxiety and post-traumatic stress disorder (PTSD), among others.
PubMed: 37626553
DOI: 10.3390/brainsci13081197