Progression of impairment in patients with vascular cognitive impairment without dementia

Transcranial Doppler sonography follow-up study in mild vascular cognitive impairment

BACKGROUND

To date, few data to transcranial Doppler sonography (TCD) are available in patients with mild vascular cognitive impairment (VCI) at risk for vascular or mixed dementia. In a previous study in patients with mild VCI and cerebral small vessels disease, a hemodynamic pattern of cerebral hypoperfusion and enhanced vascular resistance were observed; however, longitudinal data are currently lacking. Here, we perform a clinical, psychopathological, and neurosonological follow-up of patients with VCI in order to monitor any progression and to identify TCD measures to detect it.

METHODS

From the original cohort of 161 patients, 127 with VCI (mean age 73.6 ± 7.1; 67 males) were re-evaluated after 5.0 ± 1.8 years. Namely, the Montreal Cognitive Assessment (MoCA), the 17-items Hamilton Depression Rating Scale (HDRS), and the Stroop Color-Word Interference Test (StroopT) were administered to screen for global cognitive status, to quantify depressive symptoms, and to explore executive functions, respectively. Mean blood flow velocity (MBFV), peak systolic blood flow velocity (PSV), end-diastolic blood flow velocity (EDV), pulsatility index (PI), and resistivity index (RI) were recorded from the middle cerebral artery, bilaterally.

RESULTS

At follow up, patients exhibited a significant worsening of both MoCA (21.7 ± 2.1 vs. 20.7 ± 2.0) and StroopT scores (57.4 ± 19.4 vs. 59.7 ± 18.6), whereas HDRS showed an improvement, although the mean raw score remained above the cut-off value for depression (10.3 ± 6.6 vs. 9.8 ± 6.3). MBFV, PSV, and EDV showed a significant increase in PSV and PI and a reduction in EDV. When focused to younger patients (<65 years), we confirmed the significant worsening of both MoCA and StroopT but not HDRS, as well as the significant changes in PI and RI. Finally, considering the differences (D) between baseline and follow-up, the following significant correlations emerged, although with a small-to-medium effect size for all of them: positive correlation between MBFV-D and MoCA-D and between RI-D and STROOP-D, and a negative significant correlation between RI-D and MoCA-D.

CONCLUSIONS

Notwithstanding some limitations, such as the lack of a control group and neuroimaging data at follow-up, TCD may contribute to the early detection, monitoring, and management of VCI patients at risk for dementia. Together with compatible clinical and cognitive features, the exploration of early TCD markers that possibly indicate a higher risk of progression might represent an intriguing research direction and a significant clinical perspective.

Effects of exercise on patients with vascular cognitive impairment based on ACSM recommendations: a systematic review of randomized controlled trials

BACKGROUND

Exercise is considered to be an effective method for functional recovery in patients with vascular cognitive impairment (VCI), but there is a paucity of research on exercise dosage. There has been no meta-analysis of the effects of exercise therapy for vascular cognitive impairment based on the American College of Sports Medicine (ACSM) exercise prescription for a seemingly healthy population. We therefore conducted a study to analyze the effects of various exercise therapies on cognitive functioning, physical functioning, and ability to perform activities of daily living in patients diagnosed with vascular cognitive impairment.

METHODS

Four electronic databases, namely PubMed, Embase, Web of Science, and Cochrane, were systematically searched for studies examining the effects of exercise on patients with VCI. The exercise interventions were categorized into an ACSM high adherence group versus an ACSM low or indeterminate adherence group, following the recommendations for exercise testing and prescribing for seemingly healthy populations developed by ACSM. Meta-analyses were conducted using a random effects model to compare results among subgroups.

RESULTS

The study encompassed 14 trials involving 1333 subjects. Among these, 8 studies adhered highly to ACSM recommendations, while 6 studies demonstrated low or uncertain adherence. Subgroup analyses revealed differing effects: in the high adherence group, SMDs for cognitive functioning, living ability, and physical functioning were 0.53 (95% CI 0.13-0.94), 0.53 (95% CI 0.11-0.94), and 0.66 (95% CI 0.45-0.87), respectively. Conversely, in the low or indeterminate adherence group, SMDs for cognitive functioning, living ability, and physical functioning were 0.09 (95% CI - 0.13 to 0.32), - 0.11 (95% CI - 0.57 to 0.34), and 0.65 (95% CI - 0.04 to 1.35). We performed subgroup analyses by type of vascular cognitive impairment, and meta-analyses showed positive SMDs of 0.59 (95% CI 0.22-0.97) and 0.68 (95% CI 0.47-0.90) for exercise on cognitive impairment after stroke in terms of cognitive function and physical function, respectively.

CONCLUSION

The results suggest that exercise interventions exhibiting high adherence to ACSM guidelines yield more favorable outcomes concerning cognitive functioning, physical functioning, and daily living abilities among patients with VCI compared to interventions with low or uncertain adherence to ACSM recommendations.

Small vessel disease burden and functional brain connectivity in mild cognitive impairment

Background

The role of small vessel disease in the development of dementia is not yet completely understood. Functional brain connectivity has been shown to differ between individuals with and without cerebral small vessel disease. However, a comprehensive measure of small vessel disease quantifying the overall damage on the brain is not consistently used and studies using such measure in mild cognitive impairment individuals are missing.

Method

Functional brain connectivity differences were analyzed between mild cognitive impairment individuals with absent or low (n = 34) and high (n = 34) small vessel disease burden using data from the Parelsnoer Institute, a Dutch multicenter study. Small vessel disease was characterized using an ordinal scale considering: lacunes, microbleeds, perivascular spaces in the basal ganglia, and white matter hyperintensities. Resting state functional MRI data using 3 Tesla scanners was analyzed with group-independent component analysis using the CONN toolbox.

Results

Functional connectivity between areas of the cerebellum and between the cerebellum and the thalamus and caudate nucleus was higher in the absent or low small vessel disease group compared to the high small vessel disease group.

Conclusion

These findings might suggest that functional connectivity of mild cognitive impairment individuals with low or absent small vessel disease burden is more intact than in mild cognitive impairment individuals with high small vessel disease. These brain areas are mainly responsible for motor, attentional and executive functions, domains which in previous studies were found to be mostly associated with small vessel disease markers. Our results support findings on the involvement of the cerebellum in cognitive functioning.

Neuropsychological differential diagnosis of Alzheimer's disease and vascular dementia: a systematic review with meta-regressions

Introduction

Diagnostic classification systems and guidelines posit distinguishing patterns of impairment in Alzheimer's (AD) and vascular dementia (VaD). In our study, we aim to identify which diagnostic instruments distinguish them.

Methods

We searched PubMed and PsychInfo for empirical studies published until December 2020, which investigated differences in cognitive, behavioral, psychiatric, and functional measures in patients older than 64 years and reported information on VaD subtype, age, education, dementia severity, and proportion of women. We systematically reviewed these studies and conducted Bayesian hierarchical meta-regressions to quantify the evidence for differences using the Bayes factor (BF). The risk of bias was assessed using the Newcastle-Ottawa-Scale and funnel plots.

Results

We identified 122 studies with 17,850 AD and 5,247 VaD patients. Methodological limitations of the included studies are low comparability of patient groups and an untransparent patient selection process. In the digit span backward task, AD patients were nine times more probable (BF = 9.38) to outperform VaD patients (β g = 0.33, 95% ETI = 0.12, 0.52). In the phonemic fluency task, AD patients outperformed subcortical VaD (sVaD) patients (β g = 0.51, 95% ETI = 0.22, 0.77, BF = 42.36). VaD patients, in contrast, outperformed AD patients in verbal (β g = -0.61, 95% ETI = -0.97, -0.26, BF = 22.71) and visual (β g = -0.85, 95% ETI = -1.29, -0.32, BF = 13.67) delayed recall. We found the greatest difference in verbal memory, showing that sVaD patients outperform AD patients (β g = -0.64, 95% ETI = -0.88, -0.36, BF = 72.97). Finally, AD patients performed worse than sVaD patients in recognition memory tasks (β g = -0.76, 95% ETI = -1.26, -0.26, BF = 11.50).

Conclusion

Our findings show inferior performance of AD in episodic memory and superior performance in working memory. We found little support for other differences proposed by diagnostic systems and diagnostic guidelines. The utility of cognitive, behavioral, psychiatric, and functional measures in differential diagnosis is limited and should be complemented by other information. Finally, we identify research areas and avenues, which could significantly improve the diagnostic value of cognitive measures.

Efficacy of acupuncture and pharmacological therapies for vascular cognitive impairment with no dementia: a network meta-analysis

Background and objective

Vascular cognitive impairment with no dementia (VCIND) is considered to be the prodromal stage of vascular dementia, characterized by insidious onset. Although acupuncture and drug therapies are effective, the optimal therapy for VCIND remains to be further determined. Therefore, we conducted a network meta-analysis to compare the effectiveness of acupuncture therapies and current common medicines for VCIND.

Methods

We searched eight electronic databases to identify eligible randomized controlled trials of patients with VCIND treated by acupuncture or drug therapies. The primary outcome was Montreal Cognitive Assessment, and the secondary outcome was Mini-Mental State Examination. We conducted the network meta-analysis within a Bayesian framework. Weighted mean difference with 95% confidence intervals were applied as effect sizes to continuous data for all outcomes. Sensitivity analysis was done to assess the robustness of the findings, and we also carried out a subgroup analysis based on age. We assessed the risk of bias using the Risk of Bias 2.0 tool and applied the Grade of Recommendation Assessment, Development and Evaluation (GRADE) to assess the quality of the outcomes. This study was registered with PROSPERO, number CRD42022331718.

Results

A total of 33 studies with 14 interventions were included, including 2603 participants. In terms of the primary outcome, manual acupuncture plus herbal decoction was considered to be the most effective intervention (P = 91.41%), followed by electroacupuncture (P = 60.77%) and manual acupuncture plus piracetam (P = 42.58%), whereas donepezil hydrochloride ranked the least efficacious intervention (P = 54.19%). For the secondary outcome, electroacupuncture plus nimodipine was considered to be the most effective intervention (P = 42.70%), followed by manual acupuncture plus nimodipine (P = 30.62%) and manual acupuncture (P = 28.89%), whereas nimodipine ranked the least efficacious intervention (P = 44.56%).

Conclusion

Manual acupuncture plus herbal decoction might be the most effective intervention for VCIND. The combination of acupuncture and drug therapy had a tendency to perform better than monotherapy in terms of clinical outcomes.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=331718, identifier: CRD42022331718.

Development and validation of an interpretable machine learning model-Predicting mild cognitive impairment in a high-risk stroke population

Background

Mild cognitive impairment (MCI) is considered a preclinical stage of Alzheimer's disease (AD). People with MCI have a higher risk of developing dementia than healthy people. As one of the risk factors for MCI, stroke has been actively treated and intervened. Therefore, selecting the high-risk population of stroke as the research object and discovering the risk factors of MCI as early as possible can prevent the occurrence of MCI more effectively.

Methods

The Boruta algorithm was used to screen variables, and eight machine learning models were established and evaluated. The best performing models were used to assess variable importance and build an online risk calculator. Shapley additive explanation is used to explain the model.

Results

A total of 199 patients were included in the study, 99 of whom were male. Transient ischemic attack (TIA), homocysteine, education, hematocrit (HCT), diabetes, hemoglobin, red blood cells (RBC), hypertension, prothrombin time (PT) were selected by Boruta algorithm. Logistic regression (AUC = 0.8595) was the best model for predicting MCI in high-risk groups of stroke, followed by elastic network (ENET) (AUC = 0.8312), multilayer perceptron (MLP) (AUC = 0.7908), extreme gradient boosting (XGBoost) (AUC = 0.7691), and support vector machine (SVM) (AUC = 0.7527), random forest (RF) (AUC = 0.7451), K-nearest neighbors (KNN) (AUC = 0.7380), decision tree (DT) (AUC = 0.6972). The importance of variables suggests that TIA, diabetes, education, and hypertension are the top four variables of importance.

Conclusion

Transient ischemic attack (TIA), diabetes, education, and hypertension are the most important risk factors for MCI in high-risk groups of stroke, and early intervention should be performed to reduce the occurrence of MCI.

Chronic cerebral hypoperfusion: a critical feature in unravelling the etiology of vascular cognitive impairment

Vascular cognitive impairment (VCI) describes a wide spectrum of cognitive deficits related to cerebrovascular diseases. Although the loss of blood flow to cortical regions critically involved in cognitive processes must feature as the main driver of VCI, the underlying mechanisms and interactions with related disease processes remain to be fully elucidated. Recent clinical studies of cerebral blood flow measurements have supported the role of chronic cerebral hypoperfusion (CCH) as a major driver of the vascular pathology and clinical manifestations of VCI. Here we review the pathophysiological mechanisms as well as neuropathological changes of CCH. Potential interventional strategies for VCI are also reviewed. A deeper understanding of how CCH can lead to accumulation of VCI-associated pathology could potentially pave the way for early detection and development of disease-modifying therapies, thus allowing preventive interventions instead of symptomatic treatments.

Altered static and dynamic functional network connectivity in post-stroke cognitive impairment

Post-stroke cognitive impairment (PSCI) is a common symptom following brain stroke, yet the mechanisms remain unknown. This study aimed to investigate alterations of static and dynamic functional network connectivity (sFNC and dFNC) in PSCI patients. We prospectively recruited 17 PSCI patients and 24 Healthy controls (HC). Restingstate fMRI (rs-fMRI) and Mini-Mental State Examination (MMSE) were performed. Independent component analysis combined with sliding-window and K-means clustering approach were applied to examine the FNC among 11 resting-state networks: auditory network (AUDN), left executive control network (lECN), language network (LN), precuneus network (PCUN), right executive control network (rECN), salience network (SN), visuospatial network (VN), dorsal default mode network (dDMN), higher visual network (hVIS), primary visual network (pVIS), and ventral mode network (vDMN). The FNC and dynamic indices (fraction time, mean dwell time, transition number) were calculated. Static and dynamic measures were compared between two groups and the correlation between clinical and imaging indicators was analyzed. For sFNC, PSCI group showed decreased interactions in dDMN-vDMN, vDMN-SN, dDMN-hVIS, AUDN-rECN, and AUDN-VN. For dFNC, we derived 3 states of FNC that occurred repeatedly. Significant group differences were found, including decreased interactions in the AUDN-VN, AUDN-pVIS in state 2 and dDMN-VN in state 3. The mean dwell time in PSCI group was longer in state 1, and negatively correlated with MMSE score. These results demonstrated that PSCI patients are characterized with altered sFNC and dFNC, which could help us explore the neural mechanisms of the PSCI from a new perspective.

Multimodality neuroimaging in vascular mild cognitive impairment: A narrative review of current evidence

The vascular mild cognitive impairment (VaMCI) is generally accepted as the premonition stage of vascular dementia (VaD). However, most studies are focused mainly on VaD as a diagnosis in patients, thus neglecting the VaMCI stage. VaMCI stage, though, is easily diagnosed by vascular injuries and represents a high-risk period for the future decline of patients' cognitive functions. The existing studies in China and abroad have found that magnetic resonance imaging technology can provide imaging markers related to the occurrence and development of VaMCI, which is an important tool for detecting the changes in microstructure and function of VaMCI patients. Nevertheless, most of the existing studies evaluate the information of a single modal image. Due to the different imaging principles, the data provided by a single modal image are limited. In contrast, multi-modal magnetic resonance imaging research can provide multiple comprehensive data such as tissue anatomy and function. Here, a narrative review of published articles on multimodality neuroimaging in VaMCI diagnosis was conducted，and the utilization of certain neuroimaging bio-markers in clinical applications was narrated. These markers include evaluation of vascular dysfunction before tissue damages and quantification of the extent of network connectivity disruption. We further provide recommendations for early detection, progress, prompt treatment response of VaMCI, as well as optimization of the personalized treatment plan.

Diagnosis of vascular cognitive impairment: recommendations of the scientific department of cognitive neurology and aging of the Brazilian Academy of Neurology

ABSTRACT Since the publication of the latest recommendations for the diagnosis and treatment of Vascular Dementia by the Brazilian Academy of Neurology in 2011, significant advances on the terminology and diagnostic criteria have been made. This manuscript is the result of a consensus among experts appointed by the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology (2020-2022). We aimed to update practical recommendations for the identification, classification, and diagnosis of Vascular Cognitive Impairment (VCI). Searches were performed in the MEDLINE, Scopus, Scielo, and LILACS databases. This guideline provides a comprehensive review and then synthesizes the main practical guidelines for the diagnosis of VCI not only for neurologists but also for other professionals involved in the assessment and care of patients with VCI, considering the different levels of health care (primary, secondary and tertiary) in Brazil.

Diagnóstico do comprometimento cognitivo vascular: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

RESUMO Desde a publicação das últimas recomendações para o diagnóstico e tratamento da Demência Vascular pela Academia Brasileira de Neurologia em 2011, avanços significativos ocorreram na terminologia e critérios diagnósticos. O presente manuscrito é resultado do consenso entre especialistas indicados pelo Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia (2020-2022). O objetivo foi atualizar as recomendações práticas para a identificação, classificação e diagnóstico do Comprometimento Cognitivo Vascular (CCV). As buscas foram realizadas nas plataformas MEDLINE, Scopus, Scielo e LILACS. As recomendações buscam fornecer uma ampla revisão sobre o tema, então sintetizar as evidências para o diagnóstico do CCV não apenas para neurologistas, mas também para outros profissionais de saúde envolvidos na avaliação e nos cuidados ao paciente com CCV, considerando as diferentes realidades dos níveis de atenção à saúde (primário, secundário e terciário) no Brasil.

Daily mocha coffee intake and psycho-cognitive status in non-demented non-smokers subjects with subcortical ischaemic vascular disease

Coffee intake has been recently associated with better cognition and mood in mild vascular cognitive impairment (mVCI). As tobacco can reduce the caffeine half-life, we excluded smokers from the original sample. Hamilton Depression Rating Scale (HDRS), mini-mental state examination (MMSE), Stroop Colour-Word Interference Test (Stroop), activities of daily living (ADL0) and instrumental ADL were the outcome measures. Significant differences were observed in higher consumption groups (moderate intake for HDRS; high intake for MMSE and Stroop) compared to the other groups, as well as in age and education. With age, education and coffee used as independent predictors, and HDRS, Stroop and MMSE as dependent variables, a correlation was found between age and both MMSE and Stroop, as well as between education and MMSE and between HDRS and Stroop; coffee intake negatively correlated with HDRS and Stroop. Higher coffee consumption was associated with better psycho-cognitive status among non-smokers with mVCI.

Effect of Moxibustion Treatment on Degree Centrality in Patients With Mild Cognitive Impairment: A Resting-State Functional Magnetic Resonance Imaging Study

Background

Mild cognitive impairment (MCI) is a common neurological disorder. Moxibustion has been shown to be effective in treating MCI, but its therapeutic mechanisms still remain unclear. This study mainly aimed to investigate the modulation effect of moxibustion treatment for patients with MCI by functional magnetic resonance imaging (fMRI).

Methods

A total of 47 patients with MCI and 30 healthy controls (HCs) participated in resting-state fMRI imaging (rs-fMRI) scans. Patients with MCI were randomly divided into true moxibustion group (TRUE, n = 30) and sham moxibustion group (SHAM, n = 17). The degree centrality (DC) approach was applied to distinguish altered brain functions. Correlation analysis was then performed to examine the relationships between the neuroimaging findings and clinical symptoms.

Results

Compared with HCs, patients with MCI mainly showed decreased DC in the left middle frontal cortex (MFC) and bilateral middle cingulate cortex (MCC). After moxibustion treatment, the SHAM group had no significant DC findings, while TRUE group mainly showed significant increased DC in the bilateral MFC and MCC, as well as decreased DC in the left middle occipital cortex (MOC). Repeated measures analysis of variance (ANOVA) showed significant interactions between the two groups of patients with MCI. In addition, the higher Mini-Mental State Examination (MMSE) score was significantly positively correlated with increased DC in the right MFC and left MCC after moxibustion treatment.

Conclusion

Our findings demonstrate that the potential value of moxibustion treatment on MCI, which adds new insights into the popular view that moxibustion treatment may slow cognitive decline in patients with MCI.

Trigeminal Neuralgia Is a Dementia Risk Factor: A Retrospective Cohort Study

Background: Dementia, a worldwide public-health issue, is regarded as a disorder rather than a normal aging process. Trigeminal neuralgia (TN) is a chronic debilitating pain disorder that impairs daily activities. Both are most prevalent in females and in patients older than 50 years. Recent studies reveal that pain and dementia may have a reciprocal interaction with each other. Objective: In response, we estimated whether adults with TN have an increased dementia risk. Methodology: By means of Taiwan's National Health Insurance Research Database, between 1996 and 2010, 762 patients aged over 50 years in the TN group were matched with 3048 patients in the non-TN group at a ratio of 1:4. Kaplan-Meier method and Cox proportional hazard regression models were also used to determine the cumulative incidence and compare the hazard ratios of dementia in each group. Results: The incidence of dementia was higher in the TN group compared to the non-TN group. After adjusting for covariates, the TN group had a 4.47-fold higher risk of dementia compared to the non-TN group. Additionally, the impact of TN on dementia risk was larger in young-aged patients than in old-aged patients. As well, the age at the time of dementia diagnosis was younger in the TN group compared to the non-TN group. Conclusions: TN is a dementia risk factor. Given the lack of a curative therapy for dementia, early identification of TN patients may help to prevent dementia sequelae.

Neurofilament light: a possible prognostic biomarker for treatment of vascular contributions to cognitive impairment and dementia

Background

Decreased cerebral blood flow and systemic inflammation during heart failure (HF) increase the risk for vascular contributions to cognitive impairment and dementia (VCID) and Alzheimer disease-related dementias (ADRD). We previously demonstrated that PNA5, a novel glycosylated angiotensin 1–7 (Ang-(1–7)) Mas receptor (MasR) agonist peptide, is an effective therapy to rescue cognitive impairment in our preclinical model of VCID. Neurofilament light (NfL) protein concentration is correlated with cognitive impairment and elevated in neurodegenerative diseases, hypoxic brain injury, and cardiac disease. The goal of the present study was to determine (1) if treatment with Ang-(1–7)/MasR agonists can rescue cognitive impairment and decrease VCID-induced increases in NfL levels as compared to HF-saline treated mice and, (2) if NfL levels correlate with measures of cognitive function and brain cytokines in our VCID model.

Methods

VCID was induced in C57BL/6 male mice via myocardial infarction (MI). At 5 weeks post-MI, mice were treated with daily subcutaneous injections for 24 days, 5 weeks after MI, with PNA5 or angiotensin 1–7 (500 microg/kg/day or 50 microg/kg/day) or saline (n = 15/group). Following the 24-day treatment protocol, cognitive function was assessed using the Novel Object Recognition (NOR) test. Cardiac function was measured by echocardiography and plasma concentrations of NfL were quantified using a Quanterix Simoa assay. Brain and circulating cytokine levels were determined with a MILLIPLEX MAP Mouse High Sensitivity Multiplex Immunoassay. Treatment groups were compared via ANOVA, significance was set at p < 0.05.

Results

Treatment with Ang-(1–7)/MasR agonists reversed VCID-induced cognitive impairment and significantly decreased NfL levels in our mouse model of VCID as compared to HF-saline treated mice. Further, NfL levels were significantly negatively correlated with cognitive scores and the concentrations of multiple pleiotropic cytokines in the brain.

Conclusions

These data show that treatment with Ang-(1–7)/MasR agonists rescues cognitive impairment and decreases plasma NfL relative to HF-saline-treated animals in our VCID mouse model. Further, levels of NfL are significantly negatively correlated with cognitive function and with several brain cytokine concentrations. Based on these preclinical findings, we propose that circulating NfL might be a candidate for a prognostic biomarker for VCID and may also serve as a pharmacodynamic/response biomarker for therapeutic target engagement.

Altered Patterns of Amplitude of Low-Frequency Fluctuations and Fractional Amplitude of Low-Frequency Fluctuations Between Amnestic and Vascular Mild Cognitive Impairment: An ALE-Based Comparative Meta-Analysis

Background: Changes in the amplitude of low-frequency fluctuations (ALFF) and the fractional amplitude of low-frequency fluctuations (fALFF) have provided stronger evidence for the pathophysiology of cognitive impairment. Whether the altered patterns of ALFF and fALFF differ in amnestic cognitive impairment (aMCI) and vascular mild cognitive impairment (vMCI) is largely unknown. The purpose of this study was to explore the ALFF/fALFF changes in the two diseases and to further explore whether they contribute to the diagnosis and differentiation of these diseases.

Methods: We searched PubMed, Ovid, and Web of Science databases for articles on studies using the ALFF/fALFF method in patients with aMCI and vMCI. Based on the activation likelihood estimation (ALE) method, connectivity modeling based on coordinate meta-analysis and functional meta-analysis was carried out.

Results: Compared with healthy controls (HCs), patients with aMCI showed increased ALFF/fALFF in the bilateral parahippocampal gyrus/hippocampus (PHG/HG), right amygdala, right cerebellum anterior lobe (CAL), left middle temporal gyrus (MTG), left cerebrum temporal lobe sub-gyral, left inferior temporal gyrus (ITG), and left cerebrum limbic lobe uncus. Meanwhile, decreased ALFF/fALFF values were also revealed in the bilateral precuneus (PCUN), bilateral cuneus (CUN), and bilateral posterior cingulate (PC) in patients with aMCI. Compared with HCs, patients with vMCI predominantly showed decreased ALFF/fALFF in the bilateral CUN, left PCUN, left PC, and right cingulate gyrus (CG).

Conclusions: The present findings suggest that ALFF and fALFF displayed remarkable altered patterns between aMCI and vMCI when compared with HCs. Thus, the findings of this study may serve as a reliable tool for distinguishing aMCI from vMCI, which may help understand the pathophysiological mechanisms of these diseases.

Altered hippocampal functional connectivity patterns in patients with cognitive impairments following ischaemic stroke: A resting-state fMRI study

BACKGROUND

Ischemic stroke with cognitive impairment is a considerable risk factor for developing dementia. Identifying imaging markers of cognitive impairment following ischemic stroke will help to develop prevention strategies against post-stroke dementia.

METHODS

We investigated the hippocampal functional connectivity (FC) pattern following ischemic stroke, using resting-state fMRI (rs-fMRI). Thirty-three cognitively impaired patients after ischemic stroke and sixteen age-matched controls with no known history of neurological disorder were recruited for the study. No patient had a direct ischaemic insult to hippocampus on the examination of brain imaging. Seven subfields of hippocampus were used as seeds region for FC analyses.

RESULTS

Across all hippocampal subfields, FC with the inferior parietal lobule was reduced in stroke patients as compared with healthy controls. This decreased FC included both supramarginal gyrus and angular gyrus. The FC of hippocampal subfields with cerebellum was increased. Importantly, the degree of the altered FC between hippocampal subfields and inferior parietal lobule was associated with their impaired memory function.

CONCLUSION

Our results demonstrated that decreased hippocampal-inferior parietal lobule connectivity was associated with cognitive impairment in patients with ischemic stroke. These findings provide novel insights into the role of hippocampus in cognitive impairment following ischemic stroke.

Association between cortical thickness and distinct vascular cognitive impairment and dementia in patients with white matter lesions

NEW FINDINGS

What is the central question of this study? White matter lesions (WMLs) are a brain disease characterized by altered brain structural and functional connectivity, but findings have shown an inconsistent pattern: are there distinct cortical thickness changes in patients with WMLs subtypes? What is the main finding and its importance? Patients with WMLs with non-dementia vascular cognitive impairment and WMLs with vascular dementia showed distinct pathophysiology in cortical thickness. These neural correlates of WMLs should be considered in future treatment.

ABSTRACT

The effect of cortical thickness on white matter lesions (WMLs) in patients with distinct vascular cognitive impairments is relatively unknown. This study investigated the correlation between cortical thickness and vascular cognitive manifestations. WML patients and healthy controls from Beijing Tiantan Hospital between 2014 and 2018 were included. The patients were further divided into two subgroups, namely WMLs with non-dementia vascular cognitive impairment (WML-VCIND) and WMLs with vascular dementia (WML-VaD) according to the Clinical Dementia Rating (CDR) scale and the Beijing version of the Montreal Cognitive Assessment (MoCA). Changes in cortical thickness were calculated using FreeSurfer. Pearson's correlation analysis was performed to explore the relationship between cognitive manifestations and cortical thickness in WML patients. Forty-five WML patients and 23 healthy controls were recruited. The WML group exhibited significant difference in cortical thickness compared to the control group. Significantly decreased cortical thickness in the middle and superior frontal gyri, middle temporal gyrus, angular gyrus and insula was found in the WML-VaD versus WML-VCIND subgroup. Cortical thickness deficits of the left caudal middle frontal gyrus (r = 0.451, P = 0.002), left rostral middle frontal gyrus (r = 0.514, P < 0.001), left superior frontal gyrus (r = 0.410, P = 0.006), right middle temporal gyrus (r = 0.440, P = 0.003), right pars triangularis (r = 0.462, P = 0.002), right superior frontal gyrus (r = 0.434, P = 0.004) and right insula (r = 0.499, P = 0.001) were positively correlated with the MoCA score in WML patients. The specific pattern of cortical thickness deficits in the WML-VaD subgroup revealed the pathophysiology of WMLs, which should be considered in future treatment of WMLs.

Effects of Acupuncture on Vascular Cognitive Impairment with No Dementia: A Randomized Controlled Trial

Background:

Acupuncture has been used for treating vascular cognitive impairment, but evidence for its effectiveness remains limited.

Objective:

This single-center, patient-accessor blinded, randomized controlled trial was designed to assess whether acupuncture could improve the cognitive function of patients with vascular cognitive impairment with no dementia (VCIND).

Methods:

120 VCIND patients were randomly assigned to the electro-acupuncture (EA) or sham acupuncture (SA) group at a 1 : 1 ratio, with treatment conducted thrice weekly for 8 weeks. The primary outcome was the changes of cognitive function measured by the Montreal Cognitive Assessment (MoCA) from baseline to week 8. The secondary outcomes included the scores of the Mini-Mental State Examination (MMSE), the Modified Barthel Index (MBI) and the Self-rating Depression Scale (SDS). Follow-up assessments were performed with MoCA and MMSE at week 16 and 32. Linear mixed-effects models were used for analysis and all statistical tests were two-sided.

Results:

The results showed that patients in the EA group had a significantly greater improvement in MoCA score (23.85±4.18) than those in the SA group (21.48±4.44) at week 8 (95% CI = 0.80, 3.92, p = 0.04), as well as higher MoCA scores over time (p < 0.001 for interaction). Patients who received EA showed a greater increase in MMSE scores (26.41±3.47) than those who received SA (24.40±3.85) along 8 weeks (95% CI = 0.69, 3.34, p = 0.004). However, results diminished over time. No serious adverse events occurred during the trial.

Conclusion:

EA is a safe and effective technique to improve cognition over the short term of 8 weeks in VCIND patients.

NEURoaid II (MLC901) in cognitively Impaired not demenTEd patientS (NEURITES): A pilot double blind, placebo-controlled randomized trial

OBJECTIVE

To investigate the efficacy and safety of MLC901 in vascular cognitive impairment no dementia (VCIND) patients.

DESIGN

This was a multi-center, double-blind, randomized, placebo-controlled pilot study.

SETTING AND PARTICIPANT

VCIND patients from hospitals in Singapore (67), Vietnam (19), and the Philippines (17) were recruited and followed-up from March 2013 to April 2018.

METHODS

The primary outcome was executive function as measured by the Verbal Fluency (VF) and 2-part Color Trails Test (CTT). The mean difference in the scores between baseline and week 12, and baseline and week 24, was compared between MLC901 and placebo using a two-sample t-test.

RESULTS

The trial randomized 103 subjects: MLC901 (n = 57) and placebo (n = 46). The mean age of participants was 68.3 ± 8.4 years and 38.8% were female. Improvement in executive function with MLC901 was not significantly better than placebo at week 12 (CTT1 mean difference [md] 3.8 seconds, 95% confidence interval [CI]: -9.0 to 16.5, CTT2 md 10.9 seconds, 95% CI: -0.2 to 22.0), and at week 24 (CTT1 md 2.8 seconds, 95% CI: -8.4 to 14.0, CTT2 md = 4.4 seconds, 95% CI: -8.2 to 16.9). Improvement in VF from baseline was not significantly different between MLC901 and placebo at weeks 12 and 24. There were no significant differences in adverse events (43.5% vs. 56.1%) or serious adverse events (13% vs. 22.8%) in placebo versus MLC901 groups. In post hoc exploratory analysis, the treatment effect of MLC901 on cognitive function appears more apparent in subjects with existing impairment in executive function: CTT2 (md 14.4 seconds [P = .05] and 9.9 seconds [P = .3] at week 12 and week 24, respectively).

CONCLUSIONS

Whilst MLC901 appears to be safe, there was no significant cognitive benefit from MLC901 in the study population. Post hoc hypotheses generating analyses suggest that VCIND patients with existing impairment in executive function may show benefit.

Ceramide Accumulation Is Associated with Declining Verbal Memory in Coronary Artery Disease Patients: An Observational Study

Background:

Biomarkers in cognitively vulnerable populations, like those with coronary artery disease (CAD), may inform earlier intervention in vascular neurodegeneration. Circulating ceramide C18:0 (CerC18:0) is associated with changes in verbal memory in early neurodegeneration and CAD progression.

Objective:

To investigate whether plasma CerC18:0 accumulation is associated with longitudinal declines in verbal memory performance in CAD.

Methods:

In addition to total CerC18:0, we assessed its relative abundance to its precursors as ratios: CerC18:0 to monohexosylceramide C18:0 (MHxCer18:0), CerC18:0 to sphingomyelin C18:0 (SM18:0), and CerC18:0 to sphingosine-1-phosphate (S1P). Verbal memory was assessed using the California Verbal Learning Test 2^nd Ed. Using mixed models in 60 CAD participants, we evaluated associations between baseline CerC18:0 ratios and changes in verbal memory performance, adjusting for age, body mass index, and education. Given that cognitive decline is more rapid following onset of deficits, these associations were compared between those with possible mild vascular neurocognitive disorder (MVND).

Results:

Increased baseline CerC18:0 concentrations correlated with worse verbal memory performance over time (b[SE] = – 0.91[0.30], p = 0.003). Increased baseline CerC18:0/SM18:0 (b[SE] = – 1.11[`], p = 0.03) were associated with worse verbal memory performance over time. These associations were not mediated by whether or not patients had possible MVND at baseline.

Conclusion:

These findings support aberrant CerC18:0 metabolism as an early neurobiological change in vascular neurodegeneration. Future studies should measure enzymes responsible for conversion of sphingolipid precursors into CerC18:0 to assess enzymatic activity.

Vascular Cognitive Impairment and Dementia: JACC Scientific Expert Panel

Cognitive impairment associated with aging has emerged as one of the major public health challenges of our time. Although Alzheimer's disease is the leading cause of clinically diagnosed dementia in Western countries, cognitive impairment of vascular etiology is the second most common cause and may be the predominant one in East Asia. Furthermore, alterations of the large and small cerebral vasculature, including those affecting the microcirculation of the subcortical white matter, are key contributors to the clinical expression of cognitive dysfunction caused by other pathologies, including Alzheimer's disease. This scientific expert panel provides a critical appraisal of the epidemiology, pathobiology, neuropathology, and neuroimaging of vascular cognitive impairment and dementia, and of current diagnostic and therapeutic approaches. Unresolved issues are also examined to shed light on new basic and clinical research avenues that may lead to mitigating one of the most devastating human conditions.

Effectiveness of acupuncture for vascular cognitive impairment no dementia: a randomized controlled trial

OBJECTIVE:

To evaluate the effectiveness of acupuncture in patients with vascular cognitive impairment no dementia (VCIND) in comparison with citicoline, an agent for cognitive disturbances associated with chronic cerebral disorders.

DESIGN:

A randomized controlled multicenter trial.

SETTING:

In three hospitals in Beijing, China.

SUBJECTS:

A total of 216 patients with VCIND were recruited.

INTERVENTIONS:

Patients with VCIND (mean age of 65.4 years) were randomized to receive acupuncture (two sessions per week) or oral citicoline (100 mg three times daily) over three months.

MAIN MEASURES:

The primary outcome was the change from baseline to three months in cognitive symptom, measured by Alzheimer's disease Assessment Scale, cognitive subscale (ADAS-cog). Secondary outcomes included changes from baseline to six months in ADAS-cog, executive function measured by the Clock Drawing Test (CDT), and functional disability measured by the Ability of Daily Living (ADL) scale at three and six months.

RESULTS:

At three months, the acupuncture group had a greater decrease in mean ADAS-cog score (-2.33 ± 0.31) than the citicoline group (-1.38 ± 0.34) with a mean difference of -0.95 (95% CI, -1.84 to -0.07, P = 0.035). The mean change from baseline to six months in ADAS-cog also significantly favored acupuncture treatments (acupuncture change -2.61 vs citicoline -1.25, difference: -1.36 points; 95% CI, -2.20 to -0.51; P = 0.002). There was no difference between the two groups on CDT and ADL scores at either time point.

CONCLUSION:

Compared with citicoline, acupuncture has comparable and even superior efficacy with improved cognitive and daily living performance as a complementary and alternative medicine treatment for VCIND.

The efficacy and safety of nimodipine in acute ischemic stroke patients with mild cognitive impairment: a double-blind, randomized, placebo-controlled trial

Nimodipine might be effective in subcortical vascular dementia (VaD). Its benefit in preventing further cognitive decline in patients with acute ischemic stroke (AIS) and vascular mild cognitive impairment (VaMCI) remains to be established. In this multicenter, double-blind trial, we randomly assigned 654 eligible patients to nimodipine 30 mg three times a day or placebo. The primary outcome was any cognitive decline defined by the changes on the Mini-Mental State Examination (ΔMMSE ≤ -3) or vascular AD assessment scale cognitive subscale (ΔADAS-cog ≥ 4) at 6 months. Secondary outcomes included any distribution shift of ΔADAS-cog, ΔMMSE or cognitive improvement defined by ΔADAS-cog ≤ -2, or ΔMMSE ≥ 0. The primary outcome in the nimodipine group and placebo group were similar for ΔMMSE ≤ -3 (4.18% and 7.22%, respectively, P = 0.15) and ΔADAS-cog ≥ 4 (8.36% and 8.93% respectively, P = 0.88). The distribution shift of ΔADAS-cog and ΔMMSE differed significantly between the two groups (P = 0.03 and P = 0.05 respectively). Cognitive improvement occurred in 55.4% in the nimodipine group and 43.6% in the placebo group measured by ΔADAS-cog ≤ -2 (Odds Ratio, 1.54; 95% confidence interval [CI] 1.10-2.14, P < 0.01) or 84.0% and 74.6% respectively by ΔMMSE ≥ 0 (Odds Ratio, 1.79; 95% CI 1.18-2.70, P < 0.01). Nimodipine was associated with better cognitive function in the memory domain. The adverse events rate was similar in two groups. This study is registered with ClinicalTrials.gov, NCT01220622. Nimodipine did not show benefit to prevent cognitive decline in AIS patients with VaMCI, but improved cognition moderately, especially measured in the memory domain.

Cognitive improvement effects of electro-acupuncture for the treatment of MCI compared with Western medications: a systematic review and Meta-analysis

BACKGROUND

Almost half of mild cognitive impairment (MCI) patients progress to dementia, which is associated with decreased quality of life and obstacles to independent living. Relevant management is expected to prevent MCI patients from progressing to dementia. In recent years, electroacupuncture (EA) has been used to treat various kinds of neurological disorders including MCI. This study evaluates the use of EA for MCI patients to increase cognitive function through a comparison with Western medications.

METHODS

Randomized controlled trials (RCT) or systematical reviews (SR) of EA versus Western medications for MCI were searched using the following 10 databases: Pubmed, Cochrane Library, CINAHL, EMBASE, China National Knowledge Infrastructure (CNKI), National Digital Science Library (NDSL), Journal of Oriental Neuropsychiatry (JON), Korean Medical Database (KMBASE), KoreaMed, and OASIS, from October 2007 to August 2017, without language restriction. A methodological quality assessment of RCTs or SRs that met inclusion criteria was conducted using Cochrane Risk of bias (RoB) tool and a meta-analysis by RevMan (Review Manager) 5.3.5 version of Cochrane collaboration.

RESULTS

Five RCTs with 257 patients met inclusion criteria and those were randomly divided into two groups: the EA group (n = 103) and Western medications group (n = 154). The methodological quality of the included studies showed high risk or/and unclear of risk of bias. The meta-analysis of five studies reported that the EA group was better than the Western medications group, improving the Mini Mental State Examination (MMSE) score by 0.65 [95% CI 0.28~1.01] higher mean difference, Montreal Cognitive Assessment (MoCA) score by 0.66 [95% CI 0.00~1.32] higher mean difference. Adverse effects were not reported in the selected studies.

CONCLUSION

Electroacupuncture was an effective treatment for MCI patients by improving cognitive function. However, the included studies presented a low methodological quality and no adverse effects were reported. Thus, further comprehensive studies with a design in depth are needed to derive significant results.

Getting to the Heart of Alzheimer Disease

In a somewhat narrow diagnostic lens, Alzheimer disease (AD) has been considered a brain-specific disease characterized by the presence of Aβ (β-amyloid) plaques and tau neural fibrillary tangles and neural inflammation; these pathologies lead to neuronal death and consequently clinical symptoms, such as memory loss, confusion, and impaired cognitive function. However, for decades, researchers have noticed a link between various cardiovascular abnormalities and AD-such as heart failure, coronary artery disease, atrial fibrillation, and vasculopathy. A considerable volume of work has pointed at this head to heart connection, focusing mainly on associations between cerebral hypoperfusion and neuronal degradation. However, new evidence of a possible systemic or metastatic profile to AD calls for further analysis of this connection. Aβ aggregations-biochemically and structurally akin to those found in the typical AD pathology-are now known to be present in the hearts of individuals with idiopathic dilated cardiomyopathy, as well as the hearts of patients with AD. These findings suggest a potential systemic profile of proteinopathies and a new hypothesis for the link between peripheral and central symptoms of heart failure and AD. Herein, we provide an overview of the cardiovascular links to Alzheimer disease.

Vascular cognitive impairment: A preventable component of dementia

For many decades during the 20th century, the common belief was that the slow strangulation of the brains' blood supply from hardening of the brain arteries led to chronic brain ischemia and neuronal death. Not surprisingly, to counter this, vasodilators rapidly became one of the most commonly used and profitable medications worldwide; however, no clinical benefits were ever proven. In the 1970s and early 1980s cerebral blood flow studies strongly disproved the idea of brain failure due to chronic ischemia. It was also shown that infarcts and not chronic ischemia caused dementia, leading to the concept of multiinfarct dementia. In addition to infarcts, it was then realized that other vascular lesions can also cause cognitive decline. Gradually, as "atherosclerotic dementia" lost ground, Alzheimer's disease (AD) that once had been considered a presenile dementia and rare, became almost synonymous with dementia. Subsequent memory-based definitions and evaluations of dementia led to a bias in favor of diagnosing AD, overshadowing vascular contributions. The widespread use of brain imaging in the 1980s and 1990s contributed to the resurgence of evidence of cerebrovascular diseases. Moreover, it was shown that most cognitive impairment of the elderly results from mixed pathologies, emphasizing the need for a change in the traditional categorical diagnosis of dementia, e.g., AD vs vascular dementia. The alternative diagnostic method was named the vascular cognitive impairment approach, meaning identifying any impairment caused by or associated with vascular factors. The importance of this approach is that vascular lesions are currently the most important treatable and preventable components of dementia, even before any symptoms manifest, i.e., at the brain at risk stage. This chapter provides a summary of the vascular cognitive impairment approach to diagnosis, treatment, and prevention of cognitive decline.

Application of the DSM-5 Criteria for Major Neurocognitive Disorder to Vascular MCI Patients

Aims

The DSM-5 introduced the term “major neurocognitive disorders” (NCDs) to replace the previous term “dementia.” However, psychometric and functional definitions of NCDs are missing. We aimed to apply the DSM-5 criteria for diagnosing the transition to NCD to patients with mild cognitive impairment (MCI) and small vessel disease (SVD), and to define clinically significant thresholds for this transition.

Methods

The functional and cognitive features of the NCD criteria were evaluated as change from baseline and operationalized according to hierarchically ordered psychometric rules.

Results

According to the applied criteria, out of 138 patients, 44 were diagnosed with major NCD (21 with significant cognitive worsening in ≥1 additional cognitive domain), 84 remained stable, and 10 reverted to normal. Single-domain MCI patients were the most likely to revert to normal, and none progressed to major NCD. The amnestic multiple-domain MCI patients had the highest rate of progression to NCD.

Conclusion

We provide rules for the DSM-5 criteria for major NCD based on cognitive and functional changes over time, and define psychometric thresholds for clinically significant worsening to be used in longitudinal studies. According to these operationalized criteria, one-third of the MCI patients with SVD progressed to major NCD after 2 years, but only within the multiple-domain subtypes.

White Matter Changes and Cognitive Decline in a Ten-Year Follow-Up Period: A Pilot Study on a Single-Center Cohort from the Leukoaraiosis and Disability Study

AIMS

To describe the contribution of white matter lesions to the long-term neuropsychological profiles of different groups of clinical diagnoses, and to identify neuropsychological predictors of cognitive impairment in a 10-year follow-up.

METHODS

The Lisbon subcohort of the Leukoaraiosis and Disability (LADIS) study was re-evaluated performing a clinical, functional and cognitive evaluation [including Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale - Cognition (ADAS-Cog) and ADAS-Cog with the extension for vascular impairment (VADAS-Cog), the 9-word version of the California Verbal Learning Test (CVLT-9), the Trail-Making test and the Stroop test] as well as an MRI scan. Using clinical diagnostic criteria, participants were identified as having no cognitive impairment (NI), cognitive impairment but no dementia (CIND) or dementia (DEM), and the effect of time on clinical diagnosis and neuropsychological profiles was analyzed.

RESULTS

From the initial group of 66 participants, 37 out of 41 survivors (90%) were re-evaluated (mean age 81.40 years, 57% women). Fifteen patients (41%) had DEM, 12 (32%) CIND and 10 (27%) NI. Over time, the three groups presented distinct profiles in the MMSE [F2, 62 = 15.85, p = 0.000], ADAS [F2, 62 = 15.85, p = 0.000] and VADAS [F2, 48 = 5.87, p = 0.008]. Logistic regression analysis identified higher scores on MMSE (β = 1.14, p = 0.03, OR = 3.13, 95% CI 1.09-8.97) as predictors of NI after 10 years of follow-up.

CONCLUSION

Higher scores on baseline MMSE were the only neuropsychological predictors of NI after 10 years.

Examining Internet and eHealth Practices and Preferences: Survey Study of Australian Older Adults With Subjective Memory Complaints, Mild Cognitive Impairment, or Dementia

Background

Interest in electronic health (eHealth) technologies to screen for and treat a variety of medical and mental health problems is growing exponentially. However, no studies to date have investigated the feasibility of using such e-tools for older adults with mild cognitive impairment (MCI) or dementia.

Objective

The objective of this study was to describe patterns of Internet use, as well as interest in and preferences for eHealth technologies among older adults with varying degrees of cognitive impairment.

Methods

A total of 221 participants (mean age=67.6 years) attending the Healthy Brain Ageing Clinic at the University of Sydney, a specialist mood and memory clinic for adults ≥50 years of age, underwent comprehensive clinical and neuropsychological assessment and completed a 20-item self-report survey investigating current technology use and interest in eHealth technologies. Descriptive statistics and Fisher exact tests were used to characterize the findings, including variability in the results based on demographic and diagnostic factors, with diagnoses including subjective cognitive impairment (SCI), MCI, and dementia.

Results

The sample comprised 27.6% (61/221) SCI, 62.0% (137/221) MCI, and 10.4% (23/221) dementia (mean Mini-Mental State Examination=28.2). The majority of participants reported using mobile phones (201/220, 91.4%) and computers (167/194, 86.1%) routinely, with most respondents having access to the Internet at home (204/220, 92.6%). Variability was evident in the use of computers, mobile phones, and health-related websites in relation to sociodemographic factors, with younger, employed respondents with higher levels of education being more likely to utilize these technologies. Whereas most respondents used email (196/217, 90.3%), the use of social media websites was relatively uncommon. The eHealth intervention of most interest to the broader sample was memory strategy training, with 82.7% (172/208) of participants reporting they would utilize this form of intervention. Preferences for other eHealth interventions varied in relation to educational level, with university-educated participants expressing greater interest in interventions related to mood (P=.01), socialization (P=.02), memory (P=.01), and computer-based exercises (P=.046). eHealth preferences also varied in association, with diagnosis for interventions targeting sleep (P=.01), nutrition (P=.004), vascular risk factors (P=.03), and memory (P=.02).

Conclusions

Technology use is pervasive among older adults with cognitive impairment, though variability was noted in relation to age, education, vocational status, and diagnosis. There is also significant interest in Web-based interventions targeting cognition and memory, as well as other risk factors for cognitive decline, highlighting the urgent need for the development, implementation, and study of eHealth technologies tailored specifically to older adults, including those with MCI and early dementia. Strategies to promote eHealth use among older adults who are retired or have lower levels of education will also need to be considered.

Dementia risk and prevention by targeting modifiable vascular risk factors

The incidence of dementia is expected to double in the next 20 years and will contribute to heavy social and economic burden. Dementia is caused by neuronal loss that leads to brain atrophy years before symptoms manifest. Currently, no cure exists and extensive efforts are being made to mitigate cognitive impairment in late life in order to reduce the burden on patients, caregivers, and society. The most common type of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) often co-exists in the brain and shares common, modifiable risk factors, which are targeted in numerous secondary prevention trials. There is a growing need for non-pharmacological interventions and infrastructural support from governments to encourage psychosocial and behavioral interventions. Secondary prevention trials need to be redesigned based on the risk profile of individual subjects, which require the use of validated and standardized clinical, biological, and neuroimaging biomarkers. Multi-domain approaches have been proposed in high-risk populations that target optimal treatment; clinical trials need to recruit individuals at the highest risk of dementia before symptoms develop, thereby identifying an enriched disease group to test preventative and disease modifying strategies. The underlying aim should be to reduce microscopic brain tissue loss by modifying vascular and lifestyle risk factors over a relatively short period of time, thus optimizing the opportunity for preventing dementia in the future. Collaboration between international research groups is of key importance to the optimal use and allocation of existing resources, and the development of new techniques in preventing dementia. This article is part of the Special Issue "Vascular Dementia".

Pharmacotherapy for Vascular Cognitive Impairment

Vascular cognitive impairment (VCI) is the second most common type of dementia after Alzheimer's disease (AD). Stroke and cardiovascular risk factors have been linked to both AD and VCI and potentially can affect cognitive function in mid and later life. Various pharmacological agents, including donepezil, galantamine, and memantine, approved for the treatment of AD have shown modest cognitive benefits in patients with vascular dementia (VaD). However, their functional and global benefits have been inconsistent. Donepezil has shown some cognitive benefit in patients with VaD only, and galantamine has shown some benefit in mixed dementia (AD/VaD). The benefits of other drugs such as rivastigmine, memantine, nimodipine, and piracetam are not clear. Some other supplements and herbal therapies, such as citicoline, actovegin, huperzine A, and vinpocetine, have also been studied in patients with VaD, but their beneficial effects are not well established. Non-drug therapies and lifestyle modifications such as diet, exercise, and vascular risk factor control are important in the management of VCI and should not be ignored. However, there is a need for more robust clinical trials focusing on executive function and other cognitive measures and incorporation of newer imaging modalities to provide additional evidence about the utility of these strategies in patients with VCI.

Melatonin attenuated the brain damage and cognitive impairment partially through MT2 melatonin receptor in mice with chronic cerebral hypoperfusion

Background

Vascular cognitive impairment (VCI) is a spectrum of cognitive impairment caused by various chronic diseases including aging, hypertension, and diabetes mellitus. Oxidative and inflammatory reactions induced by chronic cerebral hypoperfusion (CHP) are believed to cause VCI. Melatonin is reported to possess anti-oxidation and anti-inflammation effects. This study was designed to investigate the effect and mechanisms of melatonin in CHP mice model.

Results

The behavioral function results revealed that CHP mice were significantly impaired when compared with the control. Melatonin improved the cognitive function, but the addition of MT2 receptor antagonist reversed the improvement. The IHC staining showed melatonin significantly improved WM lesions and gliosis in CHP mice. Again, the addition of MT2 receptor antagonist to melatonin worsened the WM lesion and gliosis. Similar results were also found for mRNA and protein expressions of oxidative reaction and inflammatory cytokines.

Materials and Method

Forty C57BL/6 mice were divided into four groups: Group 1: sham control; Group 2: CHP mice; Group 3: CHP with melatonin treatment; Group 4: CHP-melatonin and MT2 receptor antagonist (all groups n = 10). Working memory was assessed with Y–arm test at day-28 post-BCAS (bilateral carotid artery stenosis). All mice were sacrificed at day-30 post-BCAS. The immunohistochemical (IHC) staining was used for white matter (WM) damage and gliosis. The expression of mRNA and proteins about inflammatory and oxidative reaction were measured and compared between groups.

Conclusions

Partially through MT2 receptor, melatonin is effective for CHP-induced brain damage.

Are Astrocytes the Predominant Cell Type for Activation of Nrf2 in Aging and Neurodegeneration?

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that regulates hundreds of antioxidant genes, and is activated in response to oxidative stress. Given that many neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease and multiple sclerosis are characterised by oxidative stress, Nrf2 is commonly activated in these diseases. Evidence demonstrates that Nrf2 activity is repressed in neurons in vitro, and only cultured astrocytes respond strongly to Nrf2 inducers, leading to the interpretation that Nrf2 signalling is largely restricted to astrocytes. However, Nrf2 activity can be observed in neurons in post-mortem brain tissue and animal models of disease. Thus this interpretation may be false, and a detailed analysis of the cell type expression of Nrf2 in neurodegenerative diseases is required. This review describes the evidence for Nrf2 activation in each cell type in prominent neurodegenerative diseases and normal aging in human brain and animal models of neurodegeneration, the response to pharmacological and genetic modulation of Nrf2, and clinical trials involving Nrf2-modifying drugs.

Clinical presentations and epidemiology of vascular dementia

Cerebrovascular and cardiovascular diseases cause vascular brain injury that can lead to vascular cognitive impairment (VCI). VCI is the second most common neuropathology of dementia and mild cognitive impairment (MCI), accounting for up to one-third of the population risk. It is frequently present along with other age-related pathologies such as Alzheimer's disease (AD). Multiple etiology dementia with both VCI and AD is the single most common cause of later life dementia. There are two main clinical syndromes of VCI: post-stroke VCI in which cognitive impairment is the immediate consequence of a recent stroke and VCI without recent stroke in which cognitive impairment is the result of covert vascular brain injury detected only on neuroimaging or neuropathology. VCI is a syndrome that can result from any cause of infarction, hemorrhage, large artery disease, cardioembolism, small vessel disease, or other cerebrovascular or cardiovascular diseases. Secondary prevention of further vascular brain injury may improve outcomes in VCI.

Effect of Attention Training in Mild Cognitive Impairment Patients with Subcortical Vascular Changes: The RehAtt Study

BACKGROUND AND OBJECTIVE

Mild cognitive impairment (MCI) patients with small vessel disease (SVD) are at high dementia risk. We tested the effects of cognitive rehabilitation in these patients using the Attention Process Training-II (APT-II) program in a single-blinded, randomized clinical trial.

METHODS

Patients were randomized to APT-II or standard care and evaluated at baseline, 6, and 12 months with functional, quality of life, cognitive tests, and resting state functional MRI (rsfMRI).

RESULTS

Forty-six patients were enrolled and 43 (mean±SD age 75.1±6.8) completed the study. No change was seen in functionality and quality of life between treated and non-treated patients. However, the Rey Auditory-Verbal Learning Test immediate recall showed a significant improvement in treated compared to non-treated group (change score 6 versus 12 months: 1.8±4.9 and -1.4±3.8, p = 0.021; baseline versus 12 months: 3.8±6.1 and 0.2±4.4, p = 0.032). A higher proportion of treated patients had stable/better evaluation compared to non-treated group on Visual search test (6 versus 12 months: 95% versus 71%, p = 0.038) and Rey-Osterrieth Complex Figure copy (6 versus 12 months: 95% versus 67%, p = 0.027). RsfMRI, performed in a subsample, showed that the difference between follow-up and baseline in synchronization of activity in cerebellar areas was significantly greater in treated than in non-treated patients.

CONCLUSION

We were unable to show a significant effect in quality of life or functional status in treated patients with MCI and SVD. However, APT-II produces some beneficial effects in focused attention and working memory and seems to increase activity in brain circuits involved in cognitive processes.

The efficacy of Cognitive training in patients with VAsCular Cognitive Impairment, No dEmentia (the Cog-VACCINE study): study protocol for a randomized controlled trial

BACKGROUND

Vascular cognitive impairment, no dementia (VCIND) refers to cognitive deficits associated with underlying vascular causes that fall short of a dementia diagnosis. There is currently no treatment for VCIND. Computerized cognitive training, which has significantly improved cognitive function in healthy older adults and patients with cognitive impairment has not yet been applied to VCIND.

METHODS/DESIGN

The proposed study is a three-center, double-blinded, randomized controlled trial that will include 60 patients with VCIND. The patients will be randomized to either a training or a control group. The intervention is internet-based cognitive training performed for 30 min over 35 sessions. Neuropsychological assessment and functional and structural MRI will be performed before and after 7 weeks training. Primary outcomes are global cognitive function and executive function. Secondary outcome measures are neuroplasticity changes measured by functional and structural MRI.

DISCUSSION

Applying an internet-based, multi-domain, adaptive program, this study aims to assess whether cognitive training improves cognitive abilities and neural plasticity in patients with subcortical VCIND. In addition to the comprehensive assessment of the participants by neuropsychological tests, cerebrovascular risk factors and apolipoprotein E genotyping, neuroplasticity will be used as an evaluation outcome in this study for, to our knowledge, the first time. The combination of functional and structural MRI and neuropsychological tests will have strong sensitivity in evaluating the effects of cognitive training and will also reveal the underlying mechanisms at work.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02640716 . Retrospectively registered on 21 December 2015.

Acupuncture for amnestic mild cognitive impairment: a meta-analysis of randomised controlled trials

OBJECTIVE

Mild cognitive impairment (MCI) is a pre-dementia state; 5-10% of cases per year will evolve into dementia. MCI can be amnestic (AMCI) or non-amnestic. AMCI is associated with a higher risk of progression. In recent years, interest in acupuncture as a potential treatment for AMCI has grown. The aim of this meta-analysis was to estimate the clinical effectiveness and safety of acupuncture for AMCI.

METHODS

Randomised controlled trials (RCTs) of acupuncture versus medical treatment for AMCI were identified using the following databases from inception to July 2015: PubMed; Medline; CENTRAL; Chinese Scientific Journal Database; The Chinese Acupuncture Trials Register; China National Knowledge Infrastructure (CNKI); and Wanfang database. Data were extracted from RCTs meeting the inclusive criteria according to Cochrane methods. Meta-analyses were conducted using Rev Man V.5.3 software.

RESULTS

Five trials involving 568 subjects were included. Meta-analysis showed that participants receiving acupuncture had better outcomes than those receiving nimodipine with greater clinical efficacy rates (odds ratio (OR) 1.78, 95% CI 1.19 to 2.65; p<0.01), mini-mental state examination (MMSE) scores (mean difference (MD) 0.99, 95% CI 0.71 to 1.28; p<0.01), and picture recognition score (MD 2.12, 95% CI 1.48 to 2.75; p<0.01). Meta-analysis also showed acupuncture in conjunction with nimodipine significantly improved MMSE scores (MD 1.09, 95% CI 0.29 to 1.89; p<0.01) compared to nimodipine alone. Three trials reported adverse events. Methodological quality of the included studies was judged to be generally poor.

CONCLUSIONS

Acupuncture appears effective for AMCI when used as an alternative or adjunctive treatment; however, caution must be exercised given the low methodological quality of included trials. Further, more rigorously designed studies are needed.

Hydrogen Proton Magnetic Resonance Spectroscopy in Multidomain Amnestic Mild Cognitive Impairment and Vascular Cognitive Impairment Without Dementia

To investigate the value of hydrogen proton magnet resonance spectroscopy ((1)H-MRS) in the differential diagnosis of multiple-domain amnestic mild cognitive impairment (M-aMCI) and vascular cognitive impairment with no dementia (VCIND); (1)H-MRS was performed in patients with M-aMCI and VCIND. The level was determined for N-acetylaspartate (NAA), glutamate (Glu), inositol (mI), choline (Cho), and creatine (Cr). Compared with the normal control group, the NAA-Cr ratio in all regions studied was significantly lower in the M-aMCI and VCIND groups. The Glu-Cr ratio in the posterior cingulate gyrus of the M-aMCI group was significantly lower than in the VCIND. The mI-Cr ratio in the frontal white matter of the VCIND was significantly higher than in the M-aMCI group. In the white matter adjacent to the lateral ventricles, the Cho-Cr ratio was significantly higher in the VCIND than the M-aMCI. Our results suggested (1)H-MRS is an effective method in the differential diagnosis of M-aMCI and VCIND.

Chinese herbal medicine for patients with vascular cognitive impairment no dementia: protocol for a systematic review

INTRODUCTION

The aim of this systematic review is to assess the efficacy and safety of Chinese herbal medicine for the treatment of patients with vascular cognitive impairment but no dementia.

METHODS AND ANALYSIS

We will perform a comprehensive retrieval in the following electronic databases: PubMed, Cochrane Library, EMBASE, CINAHL, Chinese Biomedical Literature Service System (SinoMed), China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP), Wan-fang database and other sources. After screening the studies, the methodological quality of all included trials will be assessed according to the risk of bias instrument provided by the Cochrane Collaboration. A meta-analysis of randomised controlled trials will be conducted using RevMan V.5.3 software. Funnel plot analysis and Egger's test will be used to assess publication bias, if possible. The quality of evidence will be assessed by the GRADE system.

DISSEMINATION

This systematic review will be disseminated in a peer-reviewed journal and a relevant conference presentation.

TRIAL REGISTRATION NUMBER

PROSPERO CRD 42015023682.

Cholinergic circuitry functioning in patients with vascular cognitive impairment--no dementia

BACKGROUND

An impairment of central cholinergic activity, as evaluated non-invasively by the short-latency afferent inhibition (SAI) of motor responses evoked by transcranial magnetic stimulation (TMS), was observed in patients with Alzheimer's disease (AD) and amnestic Mild Cognitive Impairment. Conversely, the involvement of central cholinergic neurotransmission in vascular dementia (VaD) is still under debate and data on Vascular Cognitive Impairment--No Dementia (VCI-ND) at risk for future VaD are lacking.

OBJECTIVE

To test for the first time SAI in patients with VCI-ND.

METHODS

Single-pulse TMS measures of cortical excitability and SAI were evaluated in 25 VCI-ND patients with subcortical ischemic lesions and 20 age-matched healthy controls. Functional status, neuropsychological tests evaluating frontal lobe abilities, and white matter lesions (WMLs) load were assessed.

RESULTS

A significant difference was found between patients and controls for the mean SAI, although this result did not resist after the Bonferroni correction. In the whole group of patients and controls, SAI showed a correlation with worse scores at the Montreal Cognitive Assessment (r = 0.376, p < 0.01). SAI also positively correlated with the total vascular burden (r = 0.345, p < 0.05) but not with the WML severity.

CONCLUSIONS

Central cholinergic pathway does not seem to be involved in VCI-ND, and the current results differ from those reported in primary cholinergic forms of dementia, such as AD. SAI might represent a valuable additional tool in the differential diagnosis of the dementing processes and in identifying potential responders to cholinergic agents.

Evaluation and follow-up of cognitive functions in patients with minor stroke and transient ischemic attack

BACKGROUND AND PURPOSE

We aimed to examine the incidence of cognitive impairment among patients with stroke, the associated risk factors, progression of the cognitive impairment, and the association between the localization of the lesion(s) as detected by magnetic resonance imaging and the affected areas of cognitive function.

METHODS

A total of 40 patients over 18 years of age enduring a transient ischemic stroke or minor stroke within the past 3 months who had a minimum life expectancy of 1 year were included in this study. Same number, age-, and sex-matched individuals were included as controls. Patients were inquired on the presence of risk factors for stroke. A series of neuropsychological test batteries were administered in patient and control subjects for assessing cognitive functions. These tests were readministered at 6 and 12 months of follow-up to assess the progression of cognitive functions.

RESULTS

In this study among the patients with stroke, a significant impairment was seen in multiple cognitive functional tests following ischemic stroke as compared to control groups. The most common risk factors for stroke included hypertension (72.5%), hyperlipidemia, and cigarette smoking. The number of cognitive domains with an impairment was highest (in four cognitive tests) among those with coronary artery disease and atrial fibrillation, followed by those who had a >50% stenosis in Doppler (three cognitive tests). These findings suggest that the frequency of risk factors associated with stroke does not correlate with the frequency of risk factors associated with cognitive dysfunction. The stroke localizations were classified among the patients with stroke and reviewed in accordance with cognitive impairment.

CONCLUSION

Neuropsychological tests, clinical findings, and imaging studies should be used to document the poststroke cognitive dysfunction.

Vascular dementia

Vascular dementia is one of the most common causes of dementia after Alzheimer's disease, causing around 15% of cases. However, unlike Alzheimer's disease, there are no licensed treatments for vascular dementia. Progress in the specialty has been difficult because of uncertainties over disease classification and diagnostic criteria, controversy over the exact nature of the relation between cerebrovascular pathology and cognitive impairment, and the paucity of identifiable tractable treatment targets. Although there is an established relation between vascular and degenerative Alzheimer's pathology, the mechanistic link between the two has not yet been identified. This Series paper critiques some of the key areas and controversies, summarises treatment trials so far, and makes suggestions for what progress is needed to advance our understanding of pathogenesis and thus maximise opportunities for the search for new and effective management approaches.