Disease Assessment Scale-Cognitive Subscale Research Articles

Role of vitamin B12 and folic acid in treatment of Alzheimer's disease: a meta-analysis of randomized control trials.

Vitamin B12 and folic acid could reduce blood homocysteine levels, which was thought to slow down the progression of Alzheimer's disease (AD), but previous studies regarding the effect of vitamin B12 and folic acid in treatment of AD have not reached conclusive results. We searched PubMed and Embase until January 12, 2023. Only randomized control trials involving participants clearly diagnosed with AD and who received vitamin B12 and folic acid were enrolled. Five studies that met the criteria were selected for inclusion in the meta-analysis. Changes in cognitive function were measured based on either the Mini-Mental State Examination (MMSE) or the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog). Changes in daily life function and the level of blood homocysteine were also investigated. After a 6-month treatment, administration of vitamin B12 and folic acid improved the MMSE scores more than placebo did (SMD = 0.21, 95% CI = 0.01 to 0.32, p = 0.04) but did not significantly affect ADAS-Cog scores (SMD = 0.06, 95% CI = -0.22 to 0.33, p = 0.68) or measures of daily life function. Blood homocysteine levels were significantly decreased after vitamin B12 and folic acid treatment. Participants with AD who received 6 months of vitamin B12 and folic acid supplementation had better MMSE scores but had no difference in ADAS-Cog scores. Daily life function did not improve after treatment.

The associations of serum isoleucine with Alzheimer`s disease on assisting diagnosis, predicting conversion and assessing cognition.

Advances in blood biomarker discovery have enabled the improved diagnosis and prognosis of Alzheimer's disease (AD). Most branched-chain amino acids, except isoleucine (Ile), are correlated with both mild cognitive impairment (MCI) and AD. Therefore, this study investigated the association between serum Ile levels and MCI/AD. This study stratified 700 participants from the Alzheimer's Disease Neuroimaging Initiative database into four diagnostic groups: cognitively normal, stable MCI, progressive MCI, and AD. Analysis of covariance and chi-square analyses were used to test the demographic data. Receiver operating curve analyses were used to calculate the diagnostic accuracy of different biomarkers and were compared using MedCalc 20. Additionally, Cox proportional hazards models were used to measure the ability of serum Ile levels to predict disease conversion. Finally, a linear mixed-effects model was used to evaluate the associations between serum Ile levels and cognition, brain structure, and metabolism. Serum Ile concentration was decreased in AD and demonstrated significant diagnostic efficacy. The combination of serum Ile and cerebrospinal fluid (CSF) phosphorylated tau (P-tau) levels improved the diagnostic accuracy in AD compared to T-tau alone. Serum Ile levels significantly predicted the conversion from MCI to AD (cutoff value = 78.3 μM). Finally, the results of this study also revealed a correlation between serum Ile levels and the Alzheimer's Disease Assessment Scale cognitive subscale Q4. Serum Ile level may be a potential biomarker of AD. Ile had independent diagnostic efficacy and significantly improved the diagnostic accuracy of CSF P-tau in AD. Patients with MCI with a lower serum Ile level had a higher risk of progression to AD and a worse cognition assessment.

REsveratrol for VAscular cognitive impairment investigating cerebral Metabolism and Perfusion (REVAMP trial): a study protocol for a randomized, double-blind, placebo-controlled trial.

Carotid artery stenosis or occlusion (CASO) is a major cause of vascular cognitive impairment (VCI). There is currently no effective treatment for VCI induced by CASO. Resveratrol, a type of polyphenol, improves cognitive performance in rat CASO models via pleiotropic effects. Furthermore, we previously reported the longevity gene, SIRT1, which can be activated by resveratrol, improves cognitive and cerebral blood flow impairment in mouse CASO models by activating endothelial nitric oxide synthase. However, clinical evidence remains limited. The REsveratrol for VAscular cognitive impairment investigating cerebral Metabolism and Perfusion (REVAMP) trial is a randomized, double-blind, placebo-controlled trial involving patients with asymptomatic CASO. Each participant will receive either 150 mg/day of resveratrol or a placebo for 35 weeks. The primary objective is to determine whether resveratrol improves cognitive impairment, as assessed using the Alzheimer's disease Assessment Scale-cognitive subscale 13. One of our secondary objectives is to determine whether resveratrol improves cerebral hemodynamic impairment as assessed via 15O-gas positron emission tomography. We will recruit 100 patients (50 per group). The REVAMP trial may provide valuable insights into new therapeutic options, as multitarget neuroprotection could potentially improve cognitive function along with enhancements in cerebral hemodynamic status in patients with asymptomatic CASO.Clinical trial registration: The REVAMP trial was prospectively registered in the Japan Registry of Clinical Trials (jRCTs051230013) on April 13, 2023.

Discriminant Potential of the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) in Greek Older Adults with Subjective Cognitive Decline and Mild Cognitive Impairment.

Alzheimer's Disease Assessment Scale Cognitive Subscale (ADAS-Cog) is a widely used screening tool for detecting older adults with Alzheimer's disease among their cognitively healthy peers. A previous study in Greek population showed that ADAS-Cog-Greek (G) is a valid tool and can identify people with Alzheimer's disease from older adult control group; however, there is no current data about whether ADAS-Cog can differentiate older adults with mild cognitive impairment (MCI) from those who have subjective cognitive decline (SCD). The current study aimed to examine the discriminant potential of ADAS-Cog-G in Greek older adults who meet the criteria for SCD or MCI. Four hundred eighty-two community-dwelling older adults, visitors of the Greek Alzheimer Association and Related Disorders, were enrolled in the current study. One hundred seventy-six of them met the criteria for SCD and three hundred six had MCI. Path analysis applied to the data showed that age, as well as educational level affected ADAS-Cog-G performance. Results showed that the cut-off scores, which better discriminate people with SCD from MCI as well as their sensitivity and specificity values, were extracted in participants with high educational level (13 educational years<) and mainly under the age of 75 years. The current study provided evidence concerning the discriminant potential of ADAS-Cog-G to differentiate older adults with SCD from those with MCI in the Greek population, and therefore contributes to the relevant literature on the field.

Translation from Preclinical Research to Clinical Trials: Brain-Gut Photobiomodulation Therapy for Alzheimer's Disease.

Recently, novel non-pharmacological interventions, such as photobiomodulation (PBM) therapy, have shown promise for the treatment of Alzheimer's disease (AD). This article outlines the translation from the preclinical to clinical stages of an innovative brain-gut PBM therapy in a mouse model of AD, a pilot clinical trial involving mild-to-moderate AD patients, and a continuing pivotal clinical trial with a similar patient population. In a mouse model of AD (Aβ25-35), daily application of brain-gut PBM therapy to both the head and the abdomen produced a neuroprotective effect against the neurotoxic effects of an Aβ25-35 peptide injection by normalizing all the modified behavioral and biochemical parameters. The pilot clinical trial to evaluate brain-gut PBM therapy demonstrated the tolerability and feasibility of the novel PBM-based treatment for mild-to-moderate AD patients. Compared to the sham patients, the PBM-treated patients had lower Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) comprehension sub-scores, higher forward verbal spans, and lower Trail Making Test (TMT) Part B (TMT-B) execution times, which suggest an improvement in cognitive functions. This pilot study provided important information for the design of a novel pivotal clinical trial, currently in progress, to assess the efficacy of brain-gut PBM therapy in a larger sample of AD patients. This pivotal clinical trial could demonstrate that brain-gut PBM therapy is a safe, well-tolerated, and efficient disease-modifying treatment for mild-to-moderate AD patients and that it has medical and economic benefits.

Comparative Efficacy and Safety of Monoclonal Antibodies for Cognitive Decline in Patients with Alzheimer's Disease: A Systematic Review and Network Meta-Analysis.

Recent clinical trials of anti-Aβ monoclonal antibodies (mAbs) in the treatment of early Alzheimer's disease (AD) have produced encouraging cognitive and clinical results. The purpose of this network meta-analysis (NMA) was to compare and rank mAb drugs according to their efficacy and safety. PubMed, Embase, Web of Science, and the Cochrane Library were searched for randomized controlled trials testing various mAbs for the treatment of cognitive decline in patients with AD, up to March 31, 2023. R software (version 4.2.3) along with JAGS and STATA software (version 15.0) were used for statistical analysis. Odds ratio (OR) for binary variables, mean difference (MD) for continuous variables, and their 95% confidence intervals (CI) were utilized to estimate treatment effects and rank probabilities for each mAb in terms of safety and efficacy outcomes. We calculated the surface under the cumulative ranking area (SUCRA) to evaluate each mAb, with higher SUCRA values indicating better efficacy or lower likelihood of adverse events. Thirty-three randomized controlled trials with a total of 21,087 patients were included in the current NMA, involving eight different mAbs. SUCRA values showed that aducanumab (87.01% and 99.37%, respectively) was the most likely to achieve the best therapeutic effect based on the changes of Mini-Mental State Examination (MMSE) and Clinical Dementia Rating scale Sum of Boxes (CDR-SB) scores. Donanemab (88.50% and 99.00%, respectively) performed better than other therapies for Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and Positron Emission Tomography-Standardized Uptake Value ratio (PET-SUVr). Lecanemab (87.24%) may be the most promising way to slow down the decrease of Alzheimer's Disease Cooperative Study-Activities of Daily Living (ADCS-ADL) score. In the analysis of the incidence of adverse events (subjects with any treatment-emergent adverse event), gantenerumab (89.12%) had the least potential for adverse events, while lecanemab (0.79%) may cause more adverse events. Solanezumab (95.75% and 80.38%, respectively) had the lowest incidence of amyloid-related imaging abnormalities characterized by edema and effusion (ARIA-E) and by cerebral microhemorrhages (ARIA-H) of the included immunotherapies. While SUCRA values provided a comprehensive measure of treatment efficacy, the inherent statistical uncertainty required careful analysis in clinical application. Despite immunotherapies significantly increasing the risks of adverse events and ARIA, the data suggest that mAbs can effectively improve the cognitive function of patients with mild and moderate AD. According to the NMA, aducanumab was the most likely to achieve significant improvements in different cognitive and clinical assessments (statistically improved MMSE and CDR-SB), followed by donanemab (statistically improved ADAS-Cog, and PET-SUVr) and lecanemab (statistically improved ADCS-ADL).

Can Brain Volume-Driven Characteristic Features Predict the Response of Alzheimer's Patients to Repetitive Transcranial Magnetic Stimulation? A Pilot Study.

This study is a post-hoc examination of baseline MRI data from a clinical trial investigating the efficacy of repetitive transcranial magnetic stimulation (rTMS) as a treatment for patients with mild-moderate Alzheimer's disease (AD). Herein, we investigated whether the analysis of baseline MRI data could predict the response of patients to rTMS treatment. Whole-brain T1-weighted MRI scans of 75 participants collected at baseline were analyzed. The analyses were run on the gray matter (GM) and white matter (WM) of the left and right dorsolateral prefrontal cortex (DLPFC), as that was the rTMS application site. The primary outcome measure was the Alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog). The response to treatment was determined based on ADAS-Cog scores and secondary outcome measures. The analysis of covariance showed that responders to active treatment had a significantly lower baseline GM volume in the right DLPFC and a higher GM asymmetry index in the DLPFC region compared to those in non-responders. Logistic regression with a repeated five-fold cross-validated analysis using the MRI-driven features of the initial 75 participants provided a mean accuracy of 0.69 and an area under the receiver operating characteristic curve of 0.74 for separating responders and non-responders. The results suggest that GM volume or asymmetry in the target area of active rTMS treatment (DLPFC region in this study) may be a weak predictor of rTMS treatment efficacy. These results need more data to draw more robust conclusions.

Prevalence of mild behavioural impairment and its association with cognitive and functional impairment in normal cognition, mild cognitive impairment, and mild Alzheimer's dementia.

Mild behavioural impairment (MBI) is an emergent and persistent neuropsychiatric symptom (NPS) in subjects aged 50 and older who are at risk for cognitive decline. We examined the prevalence of MBI across the spectrum from cognitively normal (CN), mild cognitive impairment (MCI), to dementia, and further investigated the association between the MBI domain and cognitive and functional impairment. MBI was assessed in 2337 elderly patients in the Alzheimer's Disease Neuroimaging Initiative database (mean age, 73.04 years; 52.8% male). Among the subjects, 868 (37.1%) had normal cognition, 1066 (45.6%) had MCI, and 403 (17.2%) had mild Alzheimer's dementia (AD). MBI was evaluated in accordance with the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment diagnostic criteria for MBI, utilising the Neuropsychiatric Inventory. We compared the prevalence of the MBI domain with CN using multinominal logistic regression analysis and further quantified the magnitude of the association between MCI/AD and the MBI domains by calculating the population attributable risk (PAR). We assessed the association between the MBI domains and cognitive and functional impairment using simultaneous linear regression analysis. The most common MBI domains in each diagnostic group were affective dysregulation followed by impulse dyscontrol, decreased motivation, social inappropriateness, and abnormal perception or thought content. The PARs for MBI domains in subjects with MCI or AD were respectively: 16.60% and 24.34% for affective dysregulation; 3.72% and 18.06% for impulse dyscontrol; 4.78% and 14.13% for decreased motivation, 1.91% and 2.29% for social inappropriateness; and 0.68% and 3.85% for abnormal perception or thought content. All MBI domains except for social inappropriateness were significantly associated with a higher 11-item Alzheimer's Disease Assessment Scale-Cognitive Subscale total score. All MBI domains were significantly associated with a higher Functional Activities Questionnaire total score. Our findings show that MBI is highly prevalent across subjects with CN, MCI, and AD and is associated with cognitive and functional decline. MBI could be a crucial clinical phenotype relevant to the risk of cognitive and functional impairment, and provides a useful dimension pertinent to diagnostic approaches.

Potential impact of unblinding on observed treatment effects in Alzheimer's disease trials.

Adverse effects of monoclonal antibodies against amyloid beta are common, and may affect validity of randomized controlled trials (RCTs) through unblinding of participants. We used observations from published phase 3 RCTs in Alzheimer's disease to calculate the magnitude of unblinding effects on cognition that would be required to explain observed cognitive benefits in RCTs. In trials of lecanemab, aducanumab, and donanemab, incidence of amyloid-related imaging abnormalities with active treatment ranged from 22% to 44%, the vast majority of which presumably led to unblinding. Effects of unblinding on the Clinical Dementia Rating Sum of Boxes required to fully explain observed drug effects ranged from 1.1 point (95% confidence interval: 0.2-2.0) with aducanumab, to 3.3 points (2.1-4.4) with donanemab and 3.7 points (2.0-5.6) with lecanemab. Infusion-related reactions were common, with potential unblinding effects particularly for lecanemab. Similar patterns were observed for the Alzheimer's Disease Assessment Scale Cognitive subscale. Psychological treatment effects due to unblinding may explain a substantial share of observed treatment effects in RCTs.

Efficacy and safety of transcranial magnetic stimulation on cognition in mild cognitive impairment, Alzheimer's disease, Alzheimer's disease-related dementias, and other cognitive disorders: a systematic review and meta-analysis.

We aim to analyze the efficacy and safety of TMS on cognition in mild cognitive impairment (MCI), Alzheimer's disease (AD), AD-related dementias, and nondementia conditions with comorbid cognitive impairment. Systematic review, Meta-Analysis. We searched MEDLINE, Embase, Cochrane database, APA PsycINFO, Web of Science, and Scopus from January 1, 2000, to February 9, 2023. RCTs, open-label, and case series studies reporting cognitive outcomes following TMS intervention were included. Cognitive and safety outcomes were measured. Cochrane Risk of Bias for RCTs and MINORS (Methodological Index for Non-Randomized Studies) criteria were used to evaluate study quality. This study was registered with PROSPERO (CRD42022326423). The systematic review included 143 studies (n = 5,800 participants) worldwide, encompassing 94 RCTs, 43 open-label prospective, 3 open-label retrospective, and 3 case series. The meta-analysis included 25 RCTs in MCI and AD. Collectively, these studies provide evidence of improved global and specific cognitive measures with TMS across diagnostic groups. Only 2 studies (among 143) reported 4 adverse events of seizures: 3 were deemed TMS unrelated and another resolved with coil repositioning. Meta-analysis showed large effect sizes on global cognition (Mini-Mental State Examination (SMD = 0.80 [0.26, 1.33], p = 0.003), Montreal Cognitive Assessment (SMD = 0.85 [0.26, 1.44], p = 0.005), Alzheimer's Disease Assessment Scale-Cognitive Subscale (SMD = -0.96 [-1.32, -0.60], p < 0.001)) in MCI and AD, although with significant heterogeneity. The reviewed studies provide favorable evidence of improved cognition with TMS across all groups with cognitive impairment. TMS was safe and well tolerated with infrequent serious adverse events.

3D convolutional neural networks uncover modality-specific brain-imaging predictors for Alzheimer’s disease sub-scores

Different aspects of cognitive functions are affected in patients with Alzheimer’s disease. To date, little is known about the associations between features from brain-imaging and individual Alzheimer’s disease (AD)-related cognitive functional changes. In addition, how these associations differ among different imaging modalities is unclear. Here, we trained and investigated 3D convolutional neural network (CNN) models that predicted sub-scores of the 13-item Alzheimer’s Disease Assessment Scale–Cognitive Subscale (ADAS–Cog13) based on MRI and FDG–PET brain-imaging data. Analysis of the trained network showed that each key ADAS–Cog13 sub-score was associated with a specific set of brain features within an imaging modality. Furthermore, different association patterns were observed in MRI and FDG–PET modalities. According to MRI, cognitive sub-scores were typically associated with structural changes of subcortical regions, including amygdala, hippocampus, and putamen. Comparatively, according to FDG–PET, cognitive functions were typically associated with metabolic changes of cortical regions, including the cingulated gyrus, occipital cortex, middle front gyrus, precuneus cortex, and the cerebellum. These findings brought insights into complex AD etiology and emphasized the importance of investigating different brain-imaging modalities.

Abstract TMP69: Impaired Cognitive Function and Cerebral Hemodynamics Associated With APOE4 in Asymptomatic Carotid Artery Stenosis/Occlusion

Introduction: Cerebral hypoperfusion even in asymptomatic CASO may cause cognitive impairment. We reported APOE4 induces neurovascular dysfunction and cognitive impairment in a mouse model of CASO. However, it has not been clinically investigated in patients with asymptomatic CASO. Methods: A cross-sectional observational study was conducted between January 2017 and March 2022. In a primary analysis, 91 patients with asymptomatic moderate or severe CASO who underwent cognitive tests, including the Alzheimer’s Disease Assessment Scale-Cognitive Subscale 13 (ADAS-Cog), and 15 O-gas positron-emission tomography (PET) were included to examine associations of cognitive impairment and cerebral hemodynamic disruption with APOE4 . To investigate hemodynamic disruption, a sensitivity analysis in 70 additional patients who underwent only 15 O-gas PET was performed. Results: Among the 91 patients with asymptomatic moderate or severe CASO, 20 (22.0%) were APOE4 carriers. In a multivariable linear regression analysis, APOE4 was an independent risk factor for a worse ADAS-Cog delayed word recall score, indicating short-term memory impairment (β = 0.21, 95% confidence interval (CI) 0.026–2.30, p = 0.045). The 15 O-gas PET showed that APOE4 was an independent risk factor for lower cerebral blood flow (CBF) in the anterior circulation territory (β = –0.31, 95%CI –0.091 to –0.015, p = 0.007), without changes in cerebral metabolic rate of oxygen (CMRO 2 ) or oxygen extraction fraction. Of 161 patients in the sensitivity analysis, 31 (19.3%) carried APOE4 , which was an independent predictor of lower CBF (β = –0.23, 95%CI –0.072 to –0.014, p = 0.004) in the anterior circulation territory. Conclusions: APOE4 may confer an increased risk of memory impairment accompanied by cerebral hemodynamic disruption in asymptomatic CASO. The present study indicated that identifying APOE4 in such patients may be useful in early detection of disease severity.

Long-Term Resveratrol Intake for Cognitive and Cerebral Blood Flow Impairment in Carotid Artery Stenosis/Occlusion.

Carotid artery stenosis or occlusion (CASO) is a causative disease of vascular cognitive impairment (VCI) attributed to cerebral hypoperfusion, even without the development of symptomatic ischemic stroke. Preclinically, resveratrol has been demonstrated to play an important role in improving cognitive function in rodent CASO models. This study investigated the association between long-term resveratrol intake and improvements in cognitive and cerebral hemodynamic impairments in patients with CASO. A retrospective cohort study was conducted on patients with asymptomatic carotid artery stenosis of ≥50% or occlusion who underwent 15O-gas positron emission tomography (15O-gas PET) and neuropsychological tests such as Montreal Cognitive Assessment (MoCA) and Alzheimer's Disease Assessment Scale-Cognitive Subscale 13 (ADAS-Cog) twice between July 2020 and March 2022 allowing >125-day interval. Patients were administered 30 mg/day resveratrol after the first 15O-gas PET and neuropsychological tests were compared with those who were not. A total of 79 patients were enrolled in this study; 36 received resveratrol and 43 did not. Over a mean follow-up of 221.2 and 244.8 days, long-term resveratrol treatment significantly improved visuospatial/executive function (P=0.020) in MoCA, and memory domain (P=0.007) and total score (P=0.019) in ADAS-Cog. Cerebral blood flow demonstrated improvement in the right frontal lobe (P=0.027), left lenticular nucleus (P=0.009), right thalamus (P=0.035), and left thalamus (P=0.010) on 15O-gas PET. No adverse events were reported. Long-term daily intake of oral resveratrol may prevent or treat VCI by improving the cerebral blood flow in asymptomatic patients with CASO.

Study of electronic biofeedback combined with nursing intervention in the treatment of vascular cognitive impairment-no dementia.

To investigate the effects of electronic biofeedback combined with nursing intervention and conventional drug treatment on cognitive function in patients with vascular cognitive impairment-no dementia (VCIND). A total of 102 patients with VCIND treated in the Department of Neurology from January 2021 to May 2022 were enrolled and divided into the routine treatment group and biofeedback group according to different treatment methods. The routine treatment group was given conventional drug therapy and nursing intervention; for the biofeedback group, electronic biofeedback therapy was added, based on the routine treatment group. The Montreal Cognitive Assessment, (MoCA), Alzheimer's Disease Assessment Scale-Cognitive Subscale, (ADAS-cog), and Hamilton Depression Scale (HAMD) were checked before treatment, 2weeks after treatment, and 3months after treatment. At 3months of treatment, the scores of the MoCA and ADAS-cog scales in the biofeedback group were better than those in the routine treatment group, while no difference was detected in the HAMD scores before and after treatment and between the two groups. Electronic biofeedback therapy for VCIND can significantly improve the MoCA score, reduce the ADAS-cog score and improve the cognitive level of patients and can be used as a complementary treatment for VCIND.

Shortening the Alzheimer's disease assessment scale cognitive subscale.

A short yet reliable cognitive measure is needed that separates treatment and placebo for treatment trials for Alzheimer's disease. Hence, we aimed to shorten the Alzheimer's Disease Assessment Scale Cognitive Subscale (ADAS-Cog) and test its use as an efficacy measure. Secondary data analysis of participant-level data from five pivotal clinical trials of donepezil compared with placebo for Alzheimer's disease (N=2,198). Across all five trials, cognition was appraised using the original 11-item ADAS-Cog. Statistical analysis consisted of sample characterization, item response theory (IRT) to identify an ADAS-Cog short version, and mixed models for repeated-measures analysis to examine the effect sizes of ADAS-Cog change on the original and short versions in the placebo versus donepezil groups. Based on IRT, a short ADAS-Cog was developed with seven items and two response options. The original and short ADAS-Cog correlated at baseline and at weeks 12 and 24 at 0.7. Effect sizes based on mixed modeling showed that the short and original ADAS-Cog separated placebo and donepezil comparably (ADAS-Cog original ES=0.33, 95% CI=0.29, 0.40, ADAS-Cog short ES=0.25, 95% CI =0.23, 0.34). IRT identified a short ADAS-cog version that separated donepezil and placebo, suggesting its clinical potential for assessment and treatment monitoring.

Do physical fitness and cognitive function mediate the relationship between basic activities of daily living and quality of life in older adults with dementia?

PurposeIndependence in activities of daily living (ADLs) is associated with quality of life (QoL) in individuals with dementia. However, the contribution of physical and cognitive functions to this relationship needs further examination. This study aims to examine the mediating effect of physical fitness and cognitive function in the relationship between independence in basic ADLs and QoL among older adults with dementia.MethodsThis cross-sectional study included 107 older adults with dementia (74.8% women; age 78.21 ± 7.70 years). Independence in basic ADL and QoL were evaluated using the Barthel Index (BI) and QoL- Alzheimer’s Disease Scale, respectively. The Alzheimer’s Disease Assessment Scale–Cognitive Subscale and the Mini-Mental State Examination were applied to assess cognitive function. Physical fitness was evaluated using the 30-s chair stand, 2-min step and the Timed-Up and Go tests. A structural equation modelling (SEM) with bootstrapping estimation was conducted to determine the relationship between all variables.ResultsIndependence in basic ADL positively affected QoL and this association was mediated by physical fitness (β = 0.242, p = 0.011). No statistically significant results were observed when testing cognitive function as a mediator between BI and QoL (β = 0.009, p = 0.345).ConclusionsPhysical fitness (i.e., lower body strength, aerobic capacity, and mobility) plays a role in the relationship between basic ADL independence and QoL of older adults with dementia, reinforcing the need to improve and monitor these parameters throughout the disease progression. Future longitudinal studies should explore the temporal relationship between physical and cognitive function and its contribution to basic ADL independence and QoL.

Comparative Efficacy of Anti-Amyloid and Non-Antiamyloid Drugs for Treatment of Alzheimer’s Disease: A Network Meta-Analysis

BACKGROUND: Alzheimer’s disease is a degenerative neurological disorder that contributes 60-80% of all dementia cases, typically occurring at the age of 65 years. Currently available therapeutics for treatment are only capable of limiting the progression of cognitive decline. The focus of many Alzheimer’s disease drug therapies involves the hypothesized cause of pathogenesis in the disease, beta protein in the brain. Based on the Preferred Reporting Items for Meta-Analysis (PRISMA) for Network Meta-Analyses (NMA) framework, the present study was conducted to compare the efficacy of such drugs that target beta-amyloid directly or indirectly, with that of other treatments studied in randomized controlled trials. METHODS: Utilizing a network meta-analysis, direct and indirect comparisons between interventions could be done, providing a ranking of intervention in terms of efficacy in treating cognitive symptoms of Alzheimer’s disease. RESULTS: A total of 33 studies were included in four analyses of intervention trials that reported cognitive outcomes measured by Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog) or Mini-Mental State Examination (MMSE) score. Based on the findings, anti-amyloid agents did not show a marked advantage over other therapies in improving cognitive scores. Results showed that parasympathomimetic agents were consistently ranked higher in terms of Surface Under the Cumulative Ranking (SUCRA) score, with anti-tau agents providing a possible superiority over all other interventions at improving MMSE scores for treatments lasting longer than 24 weeks. High-dose anti-amyloid therapies were effective at improving MMSE score in short term treatments lasting not more than 24 weeks but fall behind other drugs in longer durations. CONCLUSION: For better understanding on the choice of anti-amyloid and non-antiamyloid therapies, future well-designed large studies including safety outcome and cost- benefit analyses on the different interventions are recommended. Additionally, anti-tau therapies show a clearer potential over anti-amyloid therapies and should thus be given more focus in future drug research.  

Lecanemab: A Humanized Monoclonal Antibody for the Treatment of Early Alzheimer Disease.

To review current pharmacology, pharmacokinetics/pharmacodynamics, safety, and efficacy of lecanemab in patients with Alzheimer disease. A literature search of PubMed (April 1, 2016-November 15, 2023) and ClinicalTrials.gov search were conducted using the following search terms: lecanemab and BAN2401. Additional articles were identified by hand from references. We included English-language clinical trials, randomized controlled trials, reviews, and systematic reviews evaluating lecanemab pharmacology, efficacy, or safety in humans for the management of Alzheimer disease. In the Clarity AD phase III trial, lecanemab led to a decrease in brain amyloid levels and showed moderate improvement in clinical measures of cognition and function. At 18 months, lecanemab 10 mg/kg biweekly exhibited a lower least squares mean change from baseline (1.21) compared to placebo (1.66) of Clinical Dementia Rating-Sum of Boxes score, signifying a significant difference of -0.45 (95% CI, -0.67 to -0.23; P < 0.001). In a subset of 698 participants, lecanemab reduced brain amyloid burden by -59.1 Centiloids (95% CI, -62.6 to -55.6). Lecanemab demonstrated favorable differences in Alzheimer Disease Assessment Scale-cognitive subscale 14, Alzheimer Disease Composite Score, and Alzheimer Disease Cooperative Study-Mild Cognitive Impairment-Activities of Daily Living scores. Adverse events included infusion-related reactions (26.4%) and amyloid-related imaging abnormalities (12.6%). Lecanemab reduces cognitive decline but raises concerns about intravenous administration, cost, and magnetic resonance imaging needs. Ongoing trials exploring subcutaneous dosing and positron emission tomography scans may offer solutions. Lecanemab is a humanized monoclonal antibody that is selective for soluble amyloid-beta (Aβ) aggregates. Lecanemab has exhibited a decrease in brain Aβ plaques and moderately less decline on clinical measures of cognitive function.

High-Frequency Repetitive Transcranial Magnetic Stimulation on Overall Cognition in Patients With Poststroke Cognitive Impairment: A Systematic Review and Meta-analysis.

The aim of the study is to comprehensively assess the recovery effects of high-frequency repetitive transcranial magnetic stimulation in patients with poststroke cognitive impairment. Six English and four Chinese databases were searched for relevant studies published up to January 2022. Randomized controlled trials of patients with poststroke cognitive impairment treated with high-frequency repetitive transcranial magnetic stimulation were included. Included studies were assessed for the risk of bias through the Cochrane Intervention Systematic Review Manual 5.1.0. The meta-analysis was performed using RevMan 5.4 software. The PRISMA 2020 guidelines were followed. Sixty-one randomized controlled trials (4012 patients) were included. Montreal Cognitive Assessment Score, Mini-Mental State Examination score, event-related potential P300 (P300) amplitude, Loewenstein Occupational Therapy Cognitive Assessment score, and total effective rate of cognitive function were higher in the high-frequency repetitive transcranial magnetic stimulation group than in the control group at the end of the treatment period, and scores of Alzheimer Disease Assessment Scale-Cognitive Subscale and P300 latency were lower in the high-frequency repetitive transcranial magnetic stimulation group than in the control group. Fifty studies had selected the dorsolateral prefrontal cortex as the stimulation site for high-frequency repetitive transcranial magnetic stimulation. Compared with nonrepetitive transcranial magnetic stimulation or sham repetitive transcranial magnetic stimulation, high-frequency repetitive transcranial magnetic stimulation not only improves the overall cognitive function of poststroke cognitive impairment patients but also has better rehabilitation results.

Magnetic Resonance Spectroscopy metabolites as biomarkers of Alzheimer’s Disease

AbstractBackgroundMagnetic resonance spectroscopy (MRS) is a non‐invasive method of evaluating metabolite levels in the cerebral cortex. Measurable metabolites can provide markers of neuronal damage, glial activation and, neurotransmission, pathological features of Alzheimer’s disease. Here we sought to establish the effectiveness of several metabolites as biomarkers for Alzheimer’s disease.Method198 participants with a single‐voxel 1H MRS scan were enrolled (n = 170 participants living with Alzheimer’s disease, n = 28 healthy controls). All participants underwent 3‐tesla magnetic resonance imaging and cognitive assessment with the Alzheimer’s Disease Assessment Scale–Cognitive Subscale (ADAS‐cog). An experienced radiographer placed an 8cm3 voxel within the posterior cingulate cortex for single‐voxel 1H MRS acquisition. Scans were then processed to evaluate levels of N‐acetylaspartate, myo‐inositol, choline, and glutamate. Creatine peak was additionally evaluated as a reference. N‐acetylaspartate/creatine, myo‐inositol /creatine, choline/creatine ratios and glutamate were compared between Alzheimer’s participants and controls to calculate the effect size. Correlations were then performed between metabolite ratios and ADAS‐cog scores.ResultN‐acetylaspartate/creatine effectively distinguished between Alzheimer’s patients and healthy controls (Cohens D = 0.83) with a lowered ratio in Alzheimer’s participants. Elevated glutamate signal and myo‐inositol/creatine ratios were also displayed in Alzheimer’s patients (Cohens D = 0.62 and 0.69, respectively). Choline/creatine ratio displayed no significant difference between groups (Cohens D = 0.26). Lower N‐acetylaspartate /creatine and glutamate correlated with higher ADAS‐cog scores (r = ‐0.29, p &lt; 0.001, CIs: ‐0.42 to ‐0.14 and r = ‐0.30, p &lt; 0.001, CIs: ‐0.44 to ‐0.16, respectively). Myo‐inositol and choline failed to correlate with cognitive impairment.ConclusionN‐acetylaspartate, a signature of neuronal damage, is an effective biomarker of Alzheimer’s disease and associated cognitive decline. Enhanced glial activity, measured with myo‐inositol, was shown in Alzheimer’s disease, suggesting that glial‐reactivity markers deserve consideration in the diagnosis of Alzheimer’s disease. Glutamate demonstrated the strongest association with cognitive impairment, despite showing a smaller effect size than N‐acetylaspartate and myo‐inositol in distinguishing between Alzheimer’s patients and controls. Together we establish MRS is a useful, non‐invasive biomarker of several pathological processes involved in the development of Alzheimer’s. Evaluation of N‐acetylaspartate, glutamate, and myo‐inositol may aid in the diagnosis of neurodegenerative disease, detecting markers undetectable by conventional MRI methodology.