Carotid atherosclerosis predicts lower cognitive test results: a 7-year follow-up study of 4,371 stroke-free subjects - the Tromsø study

Blood-Brain Barrier Permeability Is Associated With Cognitive Functioning in Normal Aging and Neurodegenerative Diseases

BACKGROUND

The purpose of this study was to investigate the relationship between blood-brain barrier (BBB) permeability and cognitive functioning in healthy older adults and individuals with neurodegenerative diseases.

METHODS AND RESULTS

A total of 124 participants with Alzheimer disease, cerebrovascular disease, or a mix Alzheimer's and cerebrovascular diseases and 55 controlparticipants underwent magnetic resonance imaging and neuropsychological testing. BBB permeability was measured with dynamic contrast-enhanced magnetic resonance imaging and white matter injury was measured using a quantitative diffusion-tensor imaging marker of white matter injury. Structural equation modeling was used to examine the relationships between BBB permeability, vascular risk burden, white matter injury, and cognitive functioning. Vascular risk burden predicted BBB permeability (r=0.24, P<0.05) and white matter injury (r=0.38, P<0.001). BBB permeability predicted increased white matter injury (r=0.34, P<0.001) and increased white matter injury predicted lower cognitive functioning (r=-0.51, P<0.001).

CONCLUSIONS

The study provides empirical support for a vascular contribution to white matter injury and cognitive impairment, directly or indirectly via BBB permeability. This highlights the importance of targeting modifiable vascular risk factors to help mitigate future cognitive decline.

Association Between Carotid Plaque and Alzheimer's Disease Cerebrospinal Fluid Biomarkers and Cognitive Function in Cognitively Intact Adults: The CABLE Study

Background

The association between carotid plaque and cognitive decline has recently been reported. However, the current research evidence is insufficient, and the possible causes of cognitive changes are unknown.

Objective

This study aims to explore the relationships between carotid plaque and cognition functions, cerebrospinal fluid (CSF) Alzheimer's disease (AD) biomarkers in cognitively intact adults, and try to study the underlying mechanisms.

Methods

We enrolled 165 cognitively normal participants from the Chinese Alzheimer's Biomarker and LifestylE (CABLE) study, who had CSF AD biomarker measurements and carotid ultrasound. Linear modeling was used to assess the association of carotid plaque with CSF biomarkers and cognition. Additionally, mediation analysis was conducted through 10,000 bootstrapped iterations to explore potential links between carotid plaque, AD pathology, and cognition.

Results

We found that carotid plaque exhibited significant correlations with Aβ42 (β = -1.173, p = 0.022), Aβ42/Aβ40 (β = -0.092, p < 0.001), P-tau/Aβ42 (β = 0.110, p = 0.045), and T-tau/Aβ42 (β = 0.451, p = 0.010). A significant correlation between carotid plaque and cognition decline was also found in men (β = -0.129, p = 0.021), and mediation analyses revealed that the effect of carotid plaque on cognitive function could be mediated by Aβ42/Aβ40 (proportion of mediation = 55.8%), P-tau/Aβ42 (proportion of mediation = 51.6%, p = 0.015) and T-tau/Aβ42 (proportion of mediation = 43.8%, p = 0.015) mediated.

Conclusions

This study demonstrated the link between carotid plaque and CSF AD biomarkers in cognitively intact adults, and the important role that AD pathology may play in the correlation between carotid plaque and cognitive changes.

A two-sample Mendelian randomization study of atherosclerosis and dementia

The causality between atherosclerosis and dementia remains unclear. This study aimed to explore the causal effect of atherosclerosis related indicators on dementia risk based on two-sample Mendelian randomization (MR) using summary statistics of genome-wide association studies (GWASs). The inverse variance weighted (IVW) method was performed as the main analysis, supplemented by different sensitivity analyses. Suggestive evidence indicated that peripheral arterial disease (PAD) (odds ratio (OR): 0.864, 95% confidence interval (CI): 0.797-0.937), coronary atherosclerosis (CoAS) (OR: 0.927, 95% CI: 0.860-0.998) and atherosclerosis, excluding cerebral, coronary, and PAD (ATHSCLE) (OR: 0.812, 95% CI: 0.725-0.909) were inversely associated with the risk of AD. The sensitivity analysis confirmed a suggestive reverse effect of ATHSCLE on the risk of frontotemporal dementia (FTD) (OR, 0.812, 95% CI, 0.725-0.909). Findings provide suggestive evidence that PAD, CoAS, and ATHSCLE might be associated with the risk of AD or FTD, which requires further exploration in larger samples.

Cognitive effects of carotid revascularization in octogenarians

BACKGROUND

Cognitive impairment is the epitome of cerebrovascular diseases, causing a significant economic burden on our health care system. Growing evidence has indicated the benefits of carotid interventions in patients with severe carotid atherosclerosis. However, the neurocognitive outcome of carotid revascularization in octogenarians is not clearly understood. We aim to evaluate postintervention cognitive changes in seniors older than 80 years.

METHODS

We prospectively recruited 170 patients undergoing carotid interventions. Neurocognitive testing was performed preoperatively and at 1, 6, and 12 months postoperatively. Episodic memory was assessed with Rey's Auditory Verbal Learning Test. Other executive functions and language measures were also evaluated at individual time points. Raw test scores were converted to z-scores or scaled scores adjusted for age and education. The sample was divided into 2 groups based on age: octogenarian (≥80 years) and nonoctogenarian (<80 years old). Postoperative cognitive scores were compared to baseline within each subcohort.

RESULTS

A total of 23 subjects (13%) were octogenarians, and 147 (87%) were younger than 80 years. Younger patients demonstrated significant cognitive improvements up to 12 months postop compared to the baseline. However, octogenarians exhibited a lack of improvement in verbal memory, measures of executive function, and language at all 3 postintervention time points.

CONCLUSION

Carotid interventions improve cognitive functions in younger patients with carotid occlusive atherosclerosis. However, no cognitive benefits were seen in male seniors older than 80 years. Further investigations are warranted to better understand the postinterventional cognitive changes in octogenarians.

Low-grade carotid artery stenosis is associated with progression of brain atrophy and cognitive decline. The SMART-MR study

Asymptomatic low-grade carotid artery stenosis (LGCS) is a common finding in patients with manifest arterial disease, however its relationship with brain MRI changes and cognitive decline is unclear. We included 902 patients (58 ± 10 years; 81% male) enrolled in the Second Manifestations of Arterial Disease - Magnetic Resonance (SMART-MR) study without a history of cerebrovascular disease. LGCS was defined as 1-49% stenosis on baseline carotid ultrasound, whereas no LGCS (reference category) was defined as absence of carotid plaque. Brain and white matter hyperintensity (WMH) volumes and cognitive function were measured at baseline and after 4 (n = 480) and 12 years (n = 222) of follow-up. Using linear mixed-effects models, we investigated associations of LGCS with progression of brain atrophy, WMH, and cognitive decline. LGCS was associated with greater progression of global brain atrophy (estimate -0.03; 95%CI, -0.06 to -0.01; p = 0.002), and a greater decline in executive functioning (estimate -0.02; 95%CI, -0.031 to -0.01; p < 0.001) and memory (estimate -0.012; 95%CI, -0.02 to -0.001; p = 0.032), independent of demographics, cardiovascular risk factors, and incident brain infarcts on MRI. No association was observed between LGCS and progression of WMH. Our results indicate that LGCS may represent an early marker of greater future brain atrophy and cognitive decline.

eICAB: A novel deep learning pipeline for Circle of Willis multiclass segmentation and analysis

BACKGROUND

The accurate segmentation, labeling and quantification of cerebral blood vessels on MR imaging is important for basic and clinical research, yet results are not generalizable, and often require user intervention. New methods are needed to automate this process.

PURPOSE

To automatically segment, label and quantify Circle of Willis (CW) arteries on Magnetic Resonance Angiography images using deep convolutional neural networks.

MATERIALS AND METHODS

MRA images were pooled from three public and private databases. A total of 116 subjects (mean age 56 years ± 21 [standard deviation]; 72 women) were used to make up the training set (N=101) and the testing set (N=15). In each image, fourteen arterial segments making up or surrounding the CW were manually annotated and validated by a clinical expert. Convolutional neural network (CNN) models were trained on a training set to be finally combined in an ensemble to develop eICAB. Model performances were evaluated using (1) quantitative analysis (dice score on test set) and (2) qualitative analysis (external datasets, N=121). The reliability was assessed using multiple MRAs of healthy participants (ICC of vessel diameters and volumes on test-retest).

RESULTS

Qualitative analysis showed that eICAB correctly predicted the large, medium and small arteries in 99±0.4%, 97±1% and 88±7% of all images, respectively. For quantitative assessment, the average dice score coefficients for the large (ICAs, BA), medium (ACAs, MCAs, PCAs-P2), and small (AComm, PComm, PCAs-P1) vessels were 0.76±0.07, 0.76±0.08 and 0.41±0.27, respectively. These results were similar and, in some cases, statistically better (p<0.05) than inter-expert annotation variability and robust to image SNR. Finally, test-retest analysis showed that the model yielded high diameter and volume reliability (ICC=0.99).

CONCLUSION

We have developed a quick and reliable open-source CNN-based method capable of accurately segmenting and labeling the CW in MRA images. This method is largely independent of image quality. In the future, we foresee this approach as a critical step towards fully automated analysis of MRA databases in basic and clinical research.

Carotid Intervention Improves Cognitive Function in Patients With Severe Atherosclerotic Carotid Disease

INTRODUCTION

Carotid revascularization procedures are effective in stroke prevention in appropriately selected patients. We sought to understand the effects of the carotid intervention on cognitive function in a well-defined cohort of prospectively recruited patients.

METHODS

A total of 170 consecutive patients undergoing carotid intervention for severe carotid stenosis were recruited. Patients received neuropsychometric testing preintervention, and at 1, 6, and 12 months postoperative. Patients were screened with the Mini-Mental State Examination. Rey Auditory Verbal Learning test (RAVLT) test was the primary outcome measure and multiple cognitive tests were used to evaluate executive function. Paired t test and McNemar test were performed to compare age-adjusted and education-adjusted postoperative scores at the individual time point with the preoperative scores.

RESULTS

Our patients had a high prevalence of cardiovascular risks and 51.2% of whom were symptomatic. The usages of statin and antiplatelet were high (88.8% and 69.4%, respectively). A total of 140 patients had 1 or more postoperative neuropsychometric tests in addition to their preoperative tests were included. The average RAVLT preoperative score was lower ( z =-0.79, SD=1.3, confidence interval: -1 to -0.53) than the age-adjusted norm. We observed a significant improvement in RAVLT memory scores at 1 and 6 months postoperative compared with preoperative. We also observed significant improvement in multiple executive functions measures up to 12 months postoperative. The improvement on patients with preoperative stroke symptoms was less consistent.

CONCLUSIONS

This prospective study showed that carotid intervention improved memory and executive function in patients with the severe carotid occlusive disease. It highlights the cognitive benefit of the carotid intervention in appropriately selected patients.

Association of subclinical atherosclerosis and cognitive decline: a community-based cross-sectional study

BACKGROUND AND AIMS

Growing burden of dementia was considered as a global public health priority as its epidemic scale rises with the world's population increases in age. In the absence of effective treatment, early identification of decline in cognitive function and risk factors that lead to the onset of dementia is a critical issue. Subclinical atherosclerosis may be a potential risk factor for cognitive impairment and progression to dementia. Research is needed to identify which subclinical atherosclerosis risk factors can better predict cognitive decline.

METHODS

A total of 1554 participants (mean age 59.81±6.93 years) were enrolled from Beijing Research on Ageing and Vessel and underwent baseline evaluation. Carotid intima-media thickness, carotid plaque and brachial ankle pulse wave velocity (ba-PWV) were selected as subclinical atherosclerosis markers. Cognitive function assessment was conducted by standardised tasks to assess the associations with subclinical atherosclerosis markers.

RESULTS

Significant associations (p<0.001) were shown in the unadjusted models between all three subclinical atherosclerosis markers and cognitive function assessments. After adjusting for covariates, in the assessment of the association between carotid atherosclerosis and cognitive function, plaque numbers showed significant associations in Montreal Cognitive Assessment (MoCA) (β=-0.15, p=0.006) and verbal memory scores (β=-0.13, p=0.013). While in the assessment of the association between arterial stiffness and cognitive function, ba-PWV showed significant associations in MoCA (β=-0.09, p=0.009) and semantic fluency scores (β=-0.13, p=0.036).

CONCLUSIONS

Positive associations shown between subclinical atherosclerosis and cognitive function. Subclinical atherosclerosis markers of plaque numbers were significantly associated with global cognitive functioning in MoCA, memory and semantic fluency, while ba-PWV was significantly associated with global cognitive functioning in MoCA and semantic fluency.

Carotid revascularization improves cognitive function in patients with asymptomatic carotid artery stenosis

OBJECTIVE

To investigate cognitive changes after carotid revascularization in elderly patients with asymptomatic carotid artery stenosis. We also compared cognitive outcomes of carotid endarterectomy with stenting in asymptomatic patients.

METHODS

From April 2019 to December 2019, patients with ≥70% asymptomatic carotid stenosis who were treated with CEA or CAS were recruited for this study. The Montreal cognitive assessment (MoCA) instrument was used to evaluate cognitive function preoperatively and postoperatively at 3, 6, and 12 months. The incidence of ipsilateral ischemic cerebrovascular events and restenosis were analyzed within 12 months.

RESULTS

In 50 patients treated with CEA or CAS, baseline cognitive function was not different between CEA and CAS groups (P > 0.05). There was no difference in the incidence of ipsilateral ischemic cerebrovascular events and restenosis within the first 12 months between the two groups. There was a significant improvement in the total MoCA score, scores of attention, and delayed recall at 3, 6 and 12 months after revascularization compared with scores at baseline (all p<0.001). At 12 months, scores of cube copying and clock drawing were significantly improved (P=0.014, P=0.020). The clock drawing score was improved at 12 months after CAS compared with CEA (P=0.040).

CONCLUSIONS

Carotid revascularization has a beneficial effect on cognition in asymptomatic patients within 12 months of the procedure. Compared with CEA, CAS show improved test scores of executive functioning by 1 year.

Subclinical carotid artery atherosclerosis and cognitive function in older adults

Background

The combined effects of increased life expectancy and the considerable number of persons reaching old age will magnify the dementia epidemic in the USA. Demonstration that subclinical atherosclerosis precedes and is associated with cognitive impairment suggests a modifiable risk factor for age-associated cognitive impairment and dementia. The purpose of this study is to determine whether subclinical atherosclerosis as measured by carotid artery intima-media thickness (CIMT) is associated with changes in cognitive function over time in older adults.

Methods

This study combined longitudinal data from three clinical trials conducted between 2000 and 2013: the B-Vitamin Atherosclerosis Intervention Trial (BVAIT), the Women’s Isoflavone Soy Health (WISH) trial, and the Early versus Late Intervention Trial with Estradiol (ELITE). Participants were recruited from the general population in the Greater Los Angeles area and were free of cardiovascular disease and diabetes; no cognitive or psychiatric exclusion criteria were specified. The same standardized protocol for ultrasound image acquisition and measurement of CIMT was used in all trials. CIMT measurements performed at baseline and 2.5 years were used in these analyses. Cognitive function was assessed at baseline and 2.5 years using a battery of 14 standardized cognitive tests. All clinical trials were conducted at the University of Southern California Atherosclerosis Research Unit, Los Angeles, and had at least 2.5 years of cognitive follow-up.

Results

A total of 308 men and 1187 women, mean age of 61 years, were included in the combined longitudinal dataset for the primary analysis. No associations were found between CIMT and cognitive function at baseline or at 2.5 years. There was a weak inverse association between CIMT measured at baseline and change in global cognition assessed over 2.5 years (β (SE) = − 0.056 (0.028) units per 0.1 mm CIMT, 95% CI − 0.110, − 0.001, p = 0.046). No associations between CIMT at baseline and changes in executive function, verbal memory, or visual memory were found.

Conclusions

In this sample of healthy older adults, our findings suggest an association between subclinical atherosclerosis and change in global cognitive function over 2.5 years. Stronger associations were observed longitudinally over 2.5 years than cross-sectionally. When analysis was stratified by age group (<65 and ≥65 years old), the inverse association remained statistically significant for participants in the older age group. Subclinical atherosclerosis of the carotid artery may be a modifiable correlate of cognitive decline in middle and older age.

Trial registration

BVAIT, NCT00114400. WISH, NCT00118846. ELITE, NCT00114517.

Intima Media Thickness and Cognitive Function Among Adults: Meta-Analysis of Observational and Longitudinal Studies

Background

Carotid structural changes measured by intima media thickness (IMT) have been related to cognitive complaints during aging. Therefore, the aims of this meta‐analysis were (1) to elucidate the relationship between vascular status, measured as IMT, and cognitive domains distinguishing between global cognition, executive functions, memory and attention; and (2) to explore whether demographic (ie, age and sex), clinical (ie, body mass index and IMT baseline values), and procedure characteristics influence this association.

Methods and Results

We performed a systematic review of MEDLINE (via PubMed), Scopus, and Web of Science databases from their inception to June 2021. Studies meeting the following inclusion criteria were included: (1) the participants were adults; (2) the exposure was carotid IMT; (3) the outcome was cognitive function, including global cognition, executive function, memory, and attention measured using standardized tests; and (4) the study design was cross‐sectional or longitudinal including unadjusted and adjusted analyses. A total of 19 cross‐sectional and 15 longitudinal studies were included and demographic (age and sex), clinical (body mass index and baseline IMT values), and procedure characteristics were analyzed as potential mediator or moderators of the association.

Conclusions

Our data support negative associations between IMT and cognitive function in cross‐sectional studies. The association between IMT and cognition lost significance in longitudinal studies and when controlling for covariates in cross‐sectional studies. Finally, the strength of these associations seems not to be modified by age, sex, body mass index, and baseline IMT values. This systematic review and meta‐analysis adds to the evidence supporting the use of IMT as a measure for identifying patients at risk of cognitive decline.

Threshold effects and interactive effects of total zinc and selenium intake on cognitive function in older adults

BACKGROUND & AIMS

The aim of this study was to assess threshold effects and interactive effects of total zinc and selenium intake on cognitive function in older adults.

METHODS

We used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Zinc and selenium intake were obtained through two 24-h dietary recalls. Cognitive performance was evaluated by the Digit Symbol Substitution Test (DSST). Smooth curve fitting, two-piecewise multivariable linear regression models, binary logistic regression model, multiplicative interactions model, and additive interactions model were used to evaluate the association between zinc, selenium intake and their interactive effect on cognitive function.

RESULTS

A total of 2450 participants aged 60 years or older were included. Zinc and selenium intake was non-linearly associated with cognitive function. The inflection point for zinc intake was 8.94 mg/d in males and 7.58 mg/d in females. When zinc intake was below inflection point, zinc intake was positively associated with the DSST test in males (β = 1.02, 95% CI, 0.44 to 1.60) and females (β = 0.94, 95% CI, 0.26 to 1.62). When zinc intake above inflection point, there is no association between zinc intake and the DSST test in both sexs. The inflection point for selenium intake was 186.33 μg/d in males and 68.40 μg/d in females. Among males, the β (95% CIs) was 0.03 (0.01,0.06) to the left side of the inflection point and -0.06 (-0.10, -0.02) to the right of the inflection point. Among females, the β (95% CIs) was 0.13 (0.04,0.22) to the left side of the inflection point and 0.01 (-0.01,0.04) to the right of the inflection point. Besides, zinc and selenium have significant interaction on DSST test only in females (P = 0.028, RERI = 0.418).

CONCLUSIONS

The present study demonstrated that zinc and selenium intake was non-linearly associated with cognitive function in different sex. There was an interactive effect between zinc and selenium intake on improving cognitive function, especially in females.

Vascular Cognitive Impairment (VCI)

Vascular cognitive impairment (VCI) is predominately caused by vascular risk factors and cerebrovascular disease. VCI includes a broad spectrum of cognitive disorders, from mild cognitive impairment to vascular dementia caused by ischemic or hemorrhagic stroke, and vascular factors alone or in a combination with neurodegeneration including Alzheimer's disease (AD) and AD-related dementia. VCI accounts for at least 20-40% of all dementia diagnosis. Growing evidence indicates that cerebrovascular pathology is the most important contributor to dementia, with additive or synergistic interactions with neurodegenerative pathology. The most common underlying mechanism of VCI is chronic age-related dysregulation of CBF, although other factors such as inflammation and cardiovascular dysfunction play a role. Vascular risk factors are prevalent in VCI and if measured in midlife they predict cognitive impairment and dementia in later life. Particularly, hypertension, high cholesterol, diabetes, and smoking at midlife are each associated with a 20 to 40% increased risk of dementia. Control of these risk factors including multimodality strategies with an inclusion of lifestyle modification is the most promising strategy for treatment and prevention of VCI. In this review, we present recent developments in age-related VCI, its mechanisms, diagnostic criteria, neuroimaging correlates, vascular risk determinants, and current intervention strategies for prevention and treatment of VCI. We have also summarized the most recent and relevant literature in the field of VCI.

A comprehensive review on RAGE-facilitated pathological pathways connecting Alzheimer’s disease, diabetes mellitus, and cardiovascular diseases

Background

Alzheimer’s disease (AD), cardiovascular disease (CVD), and diabetes are some of the most common causes of morbidity and mortality among the aging populations and cause a heavy burden on the worldwide healthcare system. In this review, we briefly highlighted cellular inflammation-based pathways of diabetes mellitus and CVD through receptor for advanced glycation end products AGEs or RAGE leading to Alzheimer’s disease and interrelation between these vascular and metabolic disorders. The articles were retrieved from Google Scholar, Science Direct, and PubMed databases using the following terms: Alzheimer’s; AGEs; RAGE; RAGE in Alzheimer’s; AGEs in Alzheimer’s; RAGE in diabetes; RAGE related pathways of CVD; RAGE in hypertension; RAGE and RAS system; RAGE and oxidative stress.

Main body of the abstract

AD is a neurodegenerative disease characterized by cognitive dysfunction and neuronal cell death. Vascular complications like hypertension, coronary artery disease, and atherosclerosis as well as metabolic syndromes like obesity and diabetes are related to the pathophysiology of AD. RAGE plays significant role in the onset and progression of AD. Amyloid plaques and neurofibrillary tangles (NFT) are two main markers of AD that regulates via RAGE and other RAGE/ligands interactions which also induces oxidative stress and a cascade of other cellular inflammation pathways leading to AD. Though AD and diabetes are two different disorders but may be inter-linked by AGEs and RAGE. In long-term hyperglycemia, upregulated AGEs interacts with RAGE and produces reactive oxygen species which induces further inflammation and vascular complications. Aging, hypercholesterolemia, atherosclerosis, hypertension, obesity, and inflammation are some of the main risk factors for both diabetes and dementia. Chronic hypertension and coronary artery disease disrupt the functions of the blood-brain barrier and are responsible for the accumulation of senile plaques and NFTs.

Short conclusion

RAGE plays a role in the etiology of Aβ and tau hyperphosphorylation, both of which contribute to cognitive impairment. So far, targeting RAGE may provide a potential sight to develop therapies against some metabolic disorders.

Effect of age stratification on the association between carotid intima-media thickness and cognitive impairment in Chinese hypertensive patients: new insight from the secondary analysis of the China Stroke Primary Prevention Trial (CSPPT)

The current study aimed to explore the association between carotid intima-media thickness (CIMT) and cognitive function assessed by the Mini-Mental State Examination (MMSE) and to examine possible effect modifiers in hypertensive patients. A total of 14,322 hypertensive participants (mean age 64.2 ± 7.4 years; 40.9% male) from the China Stroke Primary Prevention Trial (CSPPT) were included in the final analysis. CIMT was measured by ultrasound, and data were collected at the last follow-up visit; MMSE was used to evaluate cognitive function. Nonparametric smoothing plots, multivariate linear regression analysis, subgroup analyses and interaction testing were performed to examine the relationship between the CIMI and cognitive function and effect modification. The mean CIMT was 0.74 ± 0.11 mm, and the mean MMSE score was 23.5 ± 4.8. There was a significant interaction (P interaction < 0.05) in both male and female populations stratified by age (<60 vs. ≥60 years), and higher CIMT was significantly associated with decreased MMSE scores only in participants aged ≥60 years (male: β = -2.29, 95% CI -3.23 to -1.36; female: β = -1.96, 95% CI -2.97 to -0.95). Males with abnormal HDL-C showed a stronger negative association (β = -3.16, 95% CI -4.85 to -1.47) than those with normal HDL-C (normal vs. abnormal, P for interaction = 0.004). We observed that increased CIMT was significantly associated with cognitive impairment in the hypertensive population, especially among individuals with an age greater than 60 years and HDL-C deficiency. Overall, upon diagnosis of hypertension, treatment should start at the earliest opportunity to prevent end-organ damage and cognitive decline.

Transition from metabolically healthy to unhealth status associated with risk of carotid artery plaque in Chinese adults

Objective

We aimed to evaluate the association between the shift of metabolic status and future risk of carotid artery plaque (CAP) in community-based Chinese adults.

Methods

The current study included 9836 Chinese adults (4085 males and 5751 females, mean age 35.8 years) with metabolically healthy status at baseline (2013). Metabolically healthy status was defined as no self-reported history of metabolic diseases and cancer, and normal blood pressure, fasting blood glucose, glycated hemoglobin A1c level, and lipid profiles. Metabolically unhealthy status was defined if any of the following metabolic abnormalities were confirmed twice during follow up: high blood pressure, impaired glucose regulation, high triglycerides, high total cholesterol, high low-density lipoprotein cholesterols, or low high-density lipoprotein cholesterols. The transition was confirmed if participants’ metabolic status shifted from baseline healthy to unhealthy status during follow up (2014–2018).

Results

We have identified 133 incident cases of CAP during follow up. Compared to those who remained metabolically healthy, the transition to high blood pressure, high total cholesterol, and high low-density lipoprotein cholesterols, were associated with high risk of developing carotid artery plaque (Hazards ratios (HRs) ranged from 1.69 to 2.34; p < 0.05 for all). The transition to impaired glucose regulation, high total triglycerides, and low high-density lipoprotein cholesterols, were associated with high risk of carotid artery plaque only in participants with metabolically healthy overweight at baseline (HR ranged from 1.95 to 4.62; p < 0.05 for all).

Conclusion

The transition from baseline metabolically healthy status to unhealth status was associated with high risk of incident CAP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02279-w.

Impact of carotid stenosis on cerebral hemodynamic failure and cognitive impairment progression: a narrative review

Carotid atherosclerosis has a relevant impact on cerebral blood flow regulation. There is accruing evidence that hemodynamic impairment related to the presence of a significant carotid lumen narrowing may predispose to the development of cerebral dysfunctions, including a reduction in cognitive abilities. In the last years an increasing number of findings showed that carotid stenosis did contribute to cognitive impairment not only in relation to the occurrence of cerebral ischemic lesions, but also as an independent risk factor. The principal mechanisms involved are chronic hypoperfusion, microembolization and cerebrovascular reactivity impairment. Moreover, more recent studies showed alterations of regional functional connectivity. In this narrative review, we analyzed the relationships between carotid stenosis, cerebral hemodynamic derangement and cognitive impairment onset and progression, and underlined that cognitive impairment is the final result of the complex interaction between different elements, including also collateral circulation, cerebral hemodynamic status, brain connectivity and pro-inflammatory state. Further, therapeutic approaches, with a specific focus on vascular risk factors correction and on the effectiveness of surgical or endovascular interventions were discussed. We particularly focused our attention on the concept of “asymptomatic carotid stenosis”, and how could a cognitive impairment improve after an intervention, and how this could change the indications to surgical approach. Larger studies and randomized controlled trials are urgently required to better define time, characteristics and effectiveness of both medical and surgical/endovascular approaches.

Subclinical Carotid Artery Atherosclerosis and Cognitive Function: A Mini-Review

Carotid artery atherosclerosis, the result of a multitude of vascular risk factors, is a promising marker for use in risk stratification. Recent evidence suggests that carotid artery atherosclerosis affects cognitive function and is an independent risk factor for the development of cognitive impairment. Both atherosclerosis and cognitive impairment develop over a prolonged period (years), and due to the aging population, markers to identify persons at risk are needed. Carotid artery atherosclerosis can easily be visualized using non-invasive ultrasound, potentially enabling early and intensified risk factor management to preserve cognitive function or delay further decline. However, the burden of atherosclerosis and temporal exposure required to pose a risk of cognitive impairment is unclear. This mini-review aims to explore the available evidence on the association between carotid atherosclerosis and cognition, and furthermore identify the remaining gaps in knowledge.

Measurement of carotid plaque burden: A tool for predicting and preventing dementia?

•

Strokes markedly increase the risk of dementia from Alzheimer disease, and preventing strokes reduces the risk of dementia. Delaying dementia by 5 years nearly halves the incidence of dementia, because old patients often die before dementia is expressed.

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Carotid plaque burden is a strong predictor of the risk of stroke, and measurement of plaque burden has also been used to treat atherosclerosis. In high-risk patients with asymptomatic carotid stenosis, doing so was associated with a >80% reduction of the 2-year risk of stroke and myocardial infarction compared to usual therapy.

•

We found that high plaque burden was significantly associated with impairment of cognitive function.

•

We suggest that measurement of carotid plaque burden may be a powerful tool not only for predicting risk of dementia, but also for preventing dementia.

Introduction

Carotid plaque burden is a strong predictor of stroke risk, and preventing stroke reduces the risk of dementia. Treating carotid plaque burden markedly reduces the risk of stroke.

Methods

Among patients age 65–80 years attending a stroke prevention clinic, we identified those with a carotid plaque burden in the top 20% of Total Plaque Area (High TPA) and the bottom 20% (Low TPA) and performed cognitive tests: The Montreal Cognitive Assessment test (MoCA), the WAIS-III Digit Symbol-Coding Test (DSST) and Trail-Making Test (TMT) part A and B.

Results

There were 31 patients recruited; 11 Low TPA (5 men) and 20 High TPA (17 men), p = 0.04. TPA was 35 ± 25 mm² in the Low TPA vs.392 ± 169 mm² in the High TPA group (0.0001). Patients with a high plaque burden had significantly worse performance on all the cognitive tests, all p< 0.05

Discussion

A high carotid plaque burden identifies patients at risk of cognitive impairment. Because carotid plaque burden is treatable, and treating it markedly reduces the risk of stroke, we suggest that measurement of plaque burden is a useful tool for both prediction of cognitive impairment, and prevention of dementia.

Carotid atherosclerosis among middle-aged individuals predicts cognition: A 10-year follow-up study

BACKGROUND AND AIMS

There is a lack of studies simultaneously evaluating the impact of structural and functional atherosclerosis on cognition. We investigated the long-term predictive and interaction effects of structural and functional carotid atherosclerosis markers on future cognitive decline.

METHODS

Five hundred and twenty-eight middle-aged participants enrolled in the carotid atherosclerosis examination in Kaohsiung Atherosclerosis Longitudinal Study (KALS) between 2006 and 2009 were tested for cognition between 2016 and 2019. The Montreal Cognitive Assessment (MoCA) was used for the cognitive test. Baseline structural atherosclerosis was assessed by carotid intima-media thickness (cIMT) and plaque, whereas functional atherosclerosis was evaluated by carotid stiffness (β, Ep, and pulse wave velocity). Participants in the top quartile of cIMT and those with plaques were considered to have advanced structural atherosclerosis, whereas participants with all three stiffness parameters in the top quartile were defined to have advanced functional atherosclerosis.

RESULTS

The mean participant age at baseline was 53.88 ± 8.37 years. Each case of advanced structural atherosclerosis and advanced functional atherosclerosis was associated with low 10-year MoCA scores with p < 0.001 and p = 0.03, respectively. An interaction effect was observed between structural and functional atherosclerosis on the MoCA score 10 years later (p = 0.02). Participants with both advanced structural and functional markers showed a marked impact on future cognitive function, especially executive and language domains.

CONCLUSION

Carotid atherosclerosis in middle-aged individuals can predict their cognitive function in 10 years. Integrated information regarding both arterial wall and stiffness could help improve the predictive power for cognitive decline.

Micro-structural white matter abnormalities and cognitive impairment in asymptomatic carotid plaque patients: A DTI study using TBSS analysis

BACKGROUND

It has been shown that symptomatic or severe carotid atherosclerosis is closely related to cognitive impairment and brain white matter damage. However, there is still a lack of effective and non-invasive imaging biomarkers to identify early high-risk cerebrovascular diseases. Therefore, the purpose of this study is to explore the integrity of brain white matter and cognitive impairment in patients with asymptomatic carotid plaques by using imaging technology.

METHODS

All subjects were from a project of Stroke Risk Screening and Prevention and were defined as stroke high-risk patients (with three or more stroke risk factors). Tract-based spatial statistics (TBSS) based on diffusion tensor imaging (DTI) was used to analyze the whole brain white matter abnormalities in 61 patients with carotid artery plaque and in 40 healthy controls. At the same time, the general clinical data between the two groups were compared, such as age, gender, smoking, hypertension and cognitive function scores etc. Furthermore, the plaque group was divided into the have-hyperintensities group and the no-hyperintensities group to compare their microstructure of white matter injuries.

RESULTS

The cognitive scores of plaque group were significantly lower than that of control group. We found that when plaque group and control group were compared, no white matter fiber tracts with difference was found in FA, MD, AD and RD. However, the decrease of FA and the increase of RD were found in some white matter regions (P < 0.05) when comparing the have-hyperintensities group and the no-hyperintensities group. These white matter regions included anterior thalamic radiation, corticospinal tract, cingulum (cingulate gyrus), forceps minor, inferior fronto-occipital fasciculus, superior longitudinal fasciculus, uncinate fasciculus. What's more, there were significant differences in blood pressure between the two groups.

CONCLUSION

The cognitive function of patients with early high-risk cerebrovascular diseases (asymptomatic carotid plaques) has a downward trend. TBSS based on DTI can help to find out the actual damage of brain white matter in patients with early carotid plaque, and reflect the early pathological changes from the micro level.

Association Between Asymptomatic Vulnerable Carotid Plaques and Cognitive Impairment in Rural Adults

Background: The prevalence of cognitive impairment is growing and higher in rural areas. The association between carotid plaque and cognitive impairment remains uncertain, and few studies focused on the cognitive function of the rural population. We designed this study to investigate the association between carotid plaque and cognitive impairment in a rural community. Methods: We enrolled 3,336 participants who underwent carotid ultrasound and cognitive function measurements, free of cerebrovascular diseases, and without neurological deficits, from the China National Stroke Screen Survey program. Cognitive function was evaluated by the Montreal Cognitive Assessment (Beijing version). We used multivariable logistic regression to assess the association between asymptomatic carotid plaques and the presence of cognitive impairment. Results: Nine hundred seventy-six participants had cognitive impairment in this study. After adjustment for potential confounding factors, asymptomatic carotid plaques (odds ratio was 1.35; 95% confidence interval, 1.15-1.58), especially vulnerable carotid plaques (odds ratio was 1.54; 95% confidence interval, 1.28-1.85), were associated with cognitive impairment. Conclusion: In this community-based and observational study, asymptomatic vulnerable carotid plaque is an independent and significant risk factor for cognitive impairment in rural residents.

The stronger one-sided relative hypoperfusion, the more pronounced ipsilateral spatial attentional bias in patients with asymptomatic carotid stenosis

Patients with asymptomatic, high-grade internal carotid artery stenosis often suffer from subtle cognitive impairments with unclear underlying neuro-cognitive mechanisms. Thus, we hypothesized that stenosis-related unilateral cerebral hypoperfusion leads to an ipsilateral attentional bias; 22 patients with asymptomatic, one-sided high-grade carotid stenosis and 24 age-matched healthy controls underwent pseudo-continuous arterial spin labeling to assess brain perfusion in the territory of the carotid arteries. Furthermore, a parametric assessment of attention functions was carried out on the basis of the computational Theory of Visual Attention. Both patients' perfusion and spatial attention were significantly more lateralized than those of healthy controls. Critically, both asymmetry indices were significantly correlated in patients, i.e. the stronger one-sided relative hypoperfusion, the stronger ipsilateral bias of attention. This association was specifically pronounced in parietal cortices and independent of white matter hyperintensities as a surrogate for cerebrovascular brain damage. Results provide evidence for a link between lateralized hypoperfusion and lateralized attentional weighting in asymptomatic, high-grade carotid stenosis. Data suggest that lateralized hypoperfusion with simultaneous spatial attentional bias might serve as a potential therapeutic target in one-sided carotid stenosis.

Chronic cerebral hypoperfusion: An undefined, relevant entity

Despite the large body of data available, chronic cerebral hypoperfusion lacks an operative definition. In a tautological way, the term hypoperfusion is being referred to conditions of "inadequate blood flow", "defects of perfusion" or "dysfunction of autoregulation". The chronicity refers to sustained conditions or wavering states characterized by repeated phases of inefficient functional hyperemia. The phenomenon may affect the whole brain or defined areas. A few defined clinical disorders, including heart failure, hypotension, atherosclerosis of large or small vessels and carotid stenosis are thought to cause progressive brain disorders due to chronic hypoperfusion. The clinical relevance manifests mostly as neurocognitive disorders associated with neuroimaging changes.The available data support a conceptual framework that considerschronic cerebral hypoperfusiona likely, relevant pathogenic mechanism for the neurodegeneration-like progression of the neurocognitive disorders. The relationship between neuropathology, cerebral perfusion, and symptoms progression is, however, elusive for several aspects. Typical microangiopathy findings, such as MRI white matter hyperintensities, may appear in individuals without any cerebrovascular risk or vascular lesions. Pathology features of the MRI changes, such as demyelination and gliosis, may result from dysfunction of the neuro-vascular unit not directly associated withvascular mechanisms. In this review, we aim to overview the most common clinical conditions thought to reflect chronic hypoperfusion.

Cognitive improvement after carotid artery stenting in patients with symptomatic internal carotid artery near-occlusion

BACKGROUND AND PURPOSE

To investigate the influence of carotid artery stenting (CAS) with embolic protection device (EPD) on the cognitive function of patients with near-occlusion of the cervical internal carotid artery (ICA).

METHODS

From February 2014 to December 2017, a total of 79 symptomatic patients were recruited in this study. Of these patients, 31 patients refused to receive CAS therapy. They were divided into the CAS group (48 patients) and the medical treatment group (31 patients). Montreal cognitive assessment (MoCA) instrument was used for the evaluation of cognitive function. The analyzed endpoints included cumulative 12 month incidence of ipsilateral ischemic cerebrovascular events and MoCA scores at 1 month and 12 months after treatment.

RESULTS

Cumulative 12 months incidence of ipsilateral ischemic cerebrovascular events was lower in patients who underwent CAS than in patients on medical treatment (P < 0.05). In CAS group, the total MoCA score, scores of attention and delayed recall at months 1 and 12 increased when compared with those at baseline (P < 0.05). In medical treatment group, the total MoCA score and attention score at month 12 decreased when compared with those at baseline (P < 0.05). In CAS group, the total MoCA score, scores of line connection test, drawing clock, attention and delayed recall were improved at 1 and 12 months when compared with medical treatment at the same time points (P < 0.05).

CONCLUSIONS

CAS with EPD not only decreases the risk of ipsilateral TIA and stroke but also may improve the cognitive function of symptomatic patients with ICA near-occlusion.

Effect of S-equol and Soy Isoflavones on Heart and Brain

BACKGROUND

Observational studies in Asia show that dietary intake of soy isoflavones had a significant inverse association with coronary heart disease (CHD). A recent randomized controlled trial (RCT) of soy isoflavones on atherosclerosis in the US, however, failed to show their benefit. The discrepancy may be due to the much lower prevalence of S-equol producers in Westerners: Only 20-30% of Westerners produce S-equol in contrast to 50-70% in Asians. S-equol is a metabolite of dietary soy isoflavone daidzein by gut microbiome and possesses the most antiatherogenic properties among all isoflavones. Several short-duration RCTs documented that soy isoflavones improves arterial stiffness. Accumulating evidence shows that both atherosclerosis and arterial stiffness are positively associated with cognitive decline/dementia. Therefore, potentially, soy isoflavones, especially S-equol, are protective against cognitive decline/dementia.

METHODS/RESULTS

This narrative review of clinical and epidemiological studies provides an overview of the health benefits of soy isoflavones and introduces S-equol. Second, we review recent evidence on the association of soy isoflavones and S-equol with CHD, atherosclerosis, and arterial stiffness as well as the association of atherosclerosis and arterial stiffness with cognitive decline/ dementia. Third, we highlight recent studies that report the association of soy isoflavones and S-equol with cognitive decline/dementia. Lastly, we discuss the future directions of clinical and epidemiological research on the relationship of S-equol and CHD and dementia.

CONCLUSIONS

Evidence from observational studies and short-term RCTs suggests that S-equol is anti-atherogenic and improves arterial stiffness and may prevent CHD and cognitive impairment/ dementia. Well-designed long-term (≥ 2years) RCTs should be pursued.

Heart Failure and Cognitive Impairment in the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Previous studies suggest that heart failure (HF) is an independent risk factor for cognitive decline. A better understanding of the relationship between HF, cognitive status, and cognitive decline in a community-based sample may help clinicians understand disease risk.

OBJECTIVE

To examine whether persons with HF have a higher prevalence of cognitive impairment and whether persons developing HF have more rapid cognitive decline.

DESIGN

This observational cohort study of American adults in the Atherosclerosis Risk in Communities (ARIC) study has two components: cross-sectional analysis examining the association between prevalent HF and cognition using multinomial logistic regression, and change over time analysis detailing the association between incident HF and change in cognition over 15 years.

PARTICIPANTS

Among visit 5 (2011-2013) participants (median age 75 years), 6495 had neurocognitive information available for cross-sectional analysis. Change over time analysis examined the 5414 participants who had cognitive scores and no prevalent HF at visit 4 (1996-1998).

MEASUREMENTS

The primary outcome was cognitive status, classified as normal, mild cognitive impairment [MCI], and dementia on the basis of standardized cognitive tests (delayed word recall, word fluency, and digit symbol substitution). Cognitive change was examined over a 15-year period. Control variables included socio-demographic, vascular, and smoking/drinking measures.

RESULTS

At visit 5, participants with HF had a higher prevalence of dementia (adjusted relative risk ratio [RRR] = 1.60 [95% CI 1.13, 2.25]) and MCI (RRR = 1.36 [1.12, 1.64]) than those without HF. A decline in cognition between visits 4 and 5 was - 0.07 standard deviation units [- 0.13, - 0.01] greater among persons who developed HF compared to those who did not. Results did not differ by ejection fraction.

CONCLUSION

HF is associated with neurocognitive dysfunction and decline independent of other co-morbid conditions. Further study is needed to determine the underlying pathophysiology.

The associations of subclinical atherosclerotic cardiovascular disease with hip fracture risk and bone mineral density in elderly adults

In the absence of clinically recognized cardiovascular disease, increased carotid artery intimal medial thickness was associated with higher hip fracture risk in older adults, despite its association with higher bone mineral density (BMD). Low ankle brachial index and aortic wall thickness were not associated with fracture risk or BMD.

INTRODUCTION

Clinically recognized cardiovascular disease (CVD) is associated with osteoporosis and hip fracture risk, but the relationship of subclinical atherosclerosis to bone health is not certain.

METHODS

We followed 3385 participants from the Cardiovascular Health Study (mean age 74.7 ± 5.3 years) with a median time to fracture of 12.1 years who underwent baseline carotid artery and aortic wall ultrasound scanning and ankle brachial blood pressure index (ABI) determinations. A subset underwent bone mineral density (BMD) testing.

RESULTS

There were 494 hip fractures during follow-up. Among persons without clinical CVD, an average standard-deviation increase in a composite score of maximal common and internal carotid artery intimal medial thickness (cIMT) was associated with increased risk of hip fracture [(HR 1.18 [1.04, 1.35]), even though cIMT was positively associated with BMD. Neither aortic wall thickness nor ABI were associated with hip fracture risk or BMD. Among participants with clinical CVD, cIMT and aortic wall thickness, but not ABI, were associated with increased hip fracture risk.

CONCLUSION

Subclinical cIMT is associated with an increased risk of hip fractures despite being associated with increased BMD. This finding suggests that vascular health, even in its early stages, is linked to bone health, by pathways other than BMD.

Carotid circumferential wall stress is not associated with cognitive performance among individuals in late middle age: The Maastricht Study

BACKGROUND AND AIMS

Arterial remodelling aims at normalising circumferential wall stress (CWS). Greater CWS in the carotid artery has previously been associated with the prevalence and severity of cerebral small vessel disease, a major cause of ageing-related cognitive decline. Here we test the hypothesis that greater carotid CWS is associated with poorer cognitive performance.

METHODS

We studied 722 individuals (60 ± 8 years, 55% men, 42.5% highly educated, blood pressure 137 ± 19/77 ± 11 mmHg, n = 197 with type 2 diabetes) who completed a neuropsychological assessment and underwent vascular ultrasound to measure the intima-media thickness (IMT) and interadventitial diameter (IAD) of the left common carotid artery at a plaque-free site. From IMT and IAD, lumen diameter (LD) was calculated. These structural measures were then combined with local carotid pulse pressure and brachial mean arterial pressure to obtain a measure of pulsatile (CWS_pulsatile) and average (CWS_mean) mechanical load on the vessel wall. Cognitive domains assessed were memory, executive function and attention, and processing speed.

RESULTS

After adjustment for age, sex, and education, regression analyses showed that neither CWS_pulsatile nor CWS_mean were associated with measures of cognitive performance (p-values ≥0.31). This null association did not differ by age or educational level, and was observed in both individuals with and without carotid plaque, diabetes and/or hypertension. In addition, none of the individual measures of carotid structure (i.e. IMT, IAD, and LD) was related to cognitive performance.

CONCLUSIONS

The present cross-sectional study shows that carotid CWS is not associated with cognitive performance, at least not among relatively highly educated individuals in late middle age with adequately controlled cardiovascular risk factors.

Vascular biomarkers and ApoE4 expression in mild cognitive impairment and Alzheimer's disease

Vascular pathology and genetic markers such as apolipoprotein E allele ε4 (ApoE ε4) are risk factors for the progression from mild cognitive impairment (MCI) to Alzheimer's disease (AD). In Panama, a high prevalence of vascular risk factors and an increase in the aging population, generate the need to investigate biomarkers using specific, sensitive, non-invasive and cost-efficient methods that could be used in primary care. The main objective of this study was to explore the association between vascular biomarkers such as intima-media thickness (IMT) and stenosis, ApoΕ ε4 and cognitive function in a sample of older adults, including healthy controls (n = 41), MCI (n = 33), and AD (n = 12). A descriptive and cross-sectional study was conducted. Participants were part of the Panama Aging Research Initiative (PARI), the first prospective study in aging in Panama. Assessments included a neuropsychological battery, ApoΕ ε4 genotyping and a Doppler ultrasound of the left carotid artery to examine the presence of vascular risk factors. Neuropsychological tests were combined to form six cognitive domains: Global cognition, language, visuospatial abilities, learning and memory, attention and executive functions. Multivariable analyses (using age, education, and ApoE ε4 expression as covariates) were conducted. Participants with increased IMT showed poorer performance in memory and those with carotid stenosis showed poorer performance in language, visuospatial abilities and attention, independent of age, education or ApoΕ ε4 expression. The results support the use of vascular markers in cognitive assessments of aged individuals.

Association of subclinical carotid atherosclerosis with immediate memory and other cognitive functions

AIM

To clarify whether carotid atherosclerosis and its risk factors are associated with cognitive decline.

METHODS

We evaluated 206 individuals who visited our center for health screening. We carried out physical examinations, blood tests, intima-media thickness (IMT) measurement by carotid ultrasonography, brain magnetic resonance imaging scanning and cognitive function assessments. A total of 30 individuals, who had significant cerebrovascular lesions detected in magnetic resonance imaging scans, were excluded. To detect early cognitive decline, we defined "cognitive impairment (CI)" when a patient satisfied at least one of three criteria. These were Mini-Mental State Examination score <24, clock-drawing test score <4 coexisting with forgetfulness and Wechsler Memory Scale-revised delayed recall score below the normal range for the duration of education (>16 years of education: ≥9, 10-15 years: ≥5, 0-9 years: ≥3).

RESULTS

Among 176 individuals, 27 were placed in the CI group. IMT was significantly higher in the CI group as compared with the non-CI group (mean ± SD: 2.0 ± 1.0 vs 1.7 ± 0.7, P = 0018 by Student's t-test). Other atherosclerotic risk factors, such as blood pressure, low-density lipoprotein cholesterol, and hemoglobin A1c, were not significantly different between the two groups. In multivariate analysis, maximum IMT was associated with impaired immediate recall score on Wechsler Memory Scale-revised, independent of the presence of deep white matter hyperintensities on the magnetic resonance imaging scan.

CONCLUSIONS

Subclinical carotid atherosclerosis, defined as thickened IMT, could be a marker for early stages of CI, especially for immediate memory recall. The impairment is presumably caused by inducing cerebral microvascular dysfunction in the frontal lobe. Geriatr Gerontol Int 2018; 18: 65-71.

Carotid disease at age 73 and cognitive change from age 70 to 76 years: A longitudinal cohort study

Cognitive decline and carotid artery atheroma are common at older ages. In community-dwelling subjects, we assessed cognition at ages 70, 73 and 76 and carotid Doppler ultrasound at age 73, to determine whether carotid stenosis was related to cognitive decline. We used latent growth curve models to examine associations between four carotid measures (internal carotid artery stenosis, velocity, pulsatility and resistivity indices) and four cognitive ability domains (memory, visuospatial function, crystallised intelligence, processing speed) adjusted for cognitive ability at age 11, current age, gender and vascular risk factors. Amongst 866 participants, carotid stenosis (median 12.96%) was not associated with cognitive abilities at age 70 or cognitive decline from age 70 to 76. Increased ICA pulsatility and resistivity indices were associated with slower processing speed (both P < 0.001) and worse visuospatial function ( P = 0.036, 0.031, respectively) at age 70, and declining crystallised intelligence from ages 70 to 76 ( P = 0.008, 0.006, respectively). The findings suggest that vascular stiffening, rather than carotid luminal narrowing, adversely influences cognitive ageing and provides a potential target for ameliorating age-related cognitive decline.

Ultrasound Markers of Carotid Atherosclerosis and Cognition: The Northern Manhattan Study

BACKGROUND AND PURPOSE

Ultrasound markers of carotid atherosclerosis may be related to cognitive status. We hypothesized that individuals with greater carotid intima-media thickness (cIMT) and carotid plaque burden would exhibit worse cognition.

METHODS

One thousand one hundred sixty-six stroke-free participants from the NOMAS (Northern Manhattan Study) underwent carotid ultrasound and neuropsychological examination. Among them, 826 underwent a second neuropsychological examination an average of 5 years later. cIMT and plaque were assessed by a standardized B-mode ultrasound imaging and reading protocol. We used multivariable linear regression to examine cIMT, carotid plaque presence, and carotid plaque area as correlates of domain-specific neuropsychological Z scores cross-sectionally and over time. We also investigated possible effect modification by APOE ε4 allele, age, and race/ethnicity.

RESULTS

Participants had a mean (SD) age of 70 (9) years and were 60% women, 66% Hispanic, 15% white, and 18% black. Those with greater cIMT exhibited worse episodic memory after adjustment for demographics and vascular risk factors (β=-0.60; P=0.04). APOE ε4 carriers with greater cIMT exhibited worse episodic memory (β=-1.31; P=0.04), semantic memory (β=-1.45; P=0.01), and processing speed (β=-1.21; P=0.03). Participants with greater cIMT at baseline did not exhibit significantly greater cognitive decline after adjustment. APOE ε4noncarriers with greater cIMT exhibited greater declines in executive function (β=-0.98; P=0.06). Carotid plaque burden was not significantly associated with cognition at baseline or over time.

CONCLUSIONS

Subclinical carotid atherosclerosis was associated with worse cognition among those at higher risk for Alzheimer disease. Interventions targeting early stages of atherosclerosis may modify cognitive aging.

Association between Carotid Plaque and Cognitive Impairment in Chinese Stroke Population: The SOS-Stroke Study

We aimed to investigate the association between carotid plaques and cognitive impairment among patients with acute ischemic stroke, and to assess key clinical implications. In the Acute Ischemic Stroke Study, patients who received a cognitive testing and underwent complete carotid artery ultrasound scans were included. Cognitive function was measured by the mini-mental state examination. The cross-sectional relationships between cognitive impairment and carotid plaques were evaluated using multivariate logistic regression analysis. Of the 3116 patients included in this study, 826 (26.51%) patients were diagnosed with cognitive impairment. After adjusting for potential confounders, patients with ≥2 carotid plaques (odds ratio [OR] = 1.47; 95% confidence interval [CI]: 1.19–1.82), patients with ≥2 number of carotid arteries with plaque (OR = 1.48; 95% CI: 1.19–1.84) and patients with hypoechoic plaque (OR = 2.05; 95% CI: 1.24–3.38) are more likely to have cognitive impairment. In this acute ischemic stroke population, the number of carotid plaques, the number of carotid arteries with plaque and plaque stability are all associated with cognitive impairment.

Association of carotid atherosclerosis and recurrent cerebral infarction in the Chinese population: a meta-analysis

Stroke, when poor blood flow to the brain results in cell death, is the third leading cause of disability and mortality worldwide, and appears as an unequal distribution in the global population. The cumulative risk of recurrence varies greatly up to 10 years after the first stroke. Carotid atherosclerosis is a major risk factor for stroke. The aim of this study was to investigate and estimate the relationship between carotid atherosclerosis and risk of stroke recurrence in the Chinese population. We performed a systematic review and meta-analysis of randomized controlled trials published from 2000 to 2013, using the following databases: PubMed, Embase, Medline, Wanfang, and the China National Knowledge Infrastructure. The odds ratios with 95% confidence intervals were calculated to examine this strength. A total of 22 studies, including 3,912 patients, 2,506 first-ever cases, and 1,406 recurrent cases, were pooled in this meta-analysis. Our results showed that the frequency of carotid atherosclerosis is higher in recurrent cases than that in the first-ever controls (78.88% vs 59.38%), and the statistical analysis demonstrated significant positive association between carotid atherosclerosis and recurrent cerebral infarction (odds ratio: 2.87; 95% confidence interval: 2.42-3.37; P<0.00001) in a fixed-effect model. No significant heterogeneity was observed across all studies. In conclusion, our results showed that carotid atherosclerosis was associated with increased risk of recurrent stroke. However, further well-designed research with large sample sizes is still needed to identify the clear mechanism.

Relation of cerebral vessel disease to Alzheimer's disease dementia and cognitive function in elderly people: a cross-sectional study

BACKGROUND

Few data on the pathology of cerebral vessel disease, dementia, and cognition are available. We examined the association of cerebral atherosclerosis and arteriolosclerosis neuropathology with probable and possible Alzheimer's disease dementia and cognitive function.

METHODS

This cross-sectional study included men and women aged 65 years or older who had yearly clinical assessments and had agreed to brain autopsy at the time of death, as part of one of two cohort studies of ageing (The Religious Orders Study and the Rush Memory and Aging Project). Individuals without dementia or with Alzheimer's disease dementia, and with complete neuropathological data, are included in our analyses. We used neuropsychological data proximate to death to create summary measures of global cognition and cognitive domains. Clinical data recorded between 1994 and 2015 were used to determine presence of Alzheimer's disease dementia. Systematic neuropathological assessments documented the severity of cerebral large vessel (atherosclerosis) and small vessel (arteriolosclerosis) disease. By use of regression analyses adjusted for demographics, gross and microscopic infarcts, and Alzheimer's disease pathology, we examined associations of vessel disease severity (mild, moderate, and severe) with odds of probable and possible Alzheimer's disease dementia and cognitive function.

FINDINGS

Study enrolment began in January, 1994, and two cohort studies are ongoing. 1143 individuals were included in our analyses (median age at death 88·8 years; 478 [42%] with Alzheimer's disease dementia). Moderate-to-severe atherosclerosis was present in 445 (39%) individuals, and arteriolosclerosis in 401 (35%) individuals. Each level increase in the severity of atherosclerosis or arteriolosclerosis was associated with significantly higher odds of Alzheimer's disease dementia (odds ratio [OR] for atherosclerosis 1·33, 95% CI 1·11-1·58; OR for arteriolosclerosis 1·20, 1·04-1·40). Atherosclerosis was associated with lower scores for global cognition (estimate -0·10 [SE 0·04], p=0·0096) and four cognitive domains (episodic memory -0·10 [0·04], p=0·017; semantic memory -0·11 [0·05], p=0·018; perceptual speed -0·14 [0·04], p=0·00080; and visuospatial abilities -0·13 [0·04], p=0·0080), but not working memory (-0·05 [0·04], p=0·21). Arteriolosclerosis was associated with lower scores for global cognition (estimate -0·10 [0·03], p=0·0015) and four domains (episodic memory -0·12 [0·04], p=0·00090; semantic memory -0·10 [0·04], p=0·013; working memory -0·07 [0·03], p=0·045; perceptual speed -0·12 [0·04], p=0·0012), and a non-significant association was noted for visuospatial abilities (-0·07 [0·03], p=0·052). Findings were unchanged in analyses controlling for the presence of APOE ε4 allele or vascular risk factors.

INTERPRETATION

Cerebral atherosclerosis and arteriolosclerosis are associated with Alzheimer's disease dementia, and are also associated with low scores in most cognitive domains. Cerebral vessel pathology might be an under-recognised risk factor for Alzheimer's disease dementia.

FUNDING

US National Institutes of Health.

Neurovascular dysfunction and neurodegeneration in dementia and Alzheimer's disease

Vascular insults can initiate a cascade of molecular events leading to neurodegeneration, cognitive impairment, and dementia. Here, we review the cellular and molecular mechanisms in cerebral blood vessels and the pathophysiological events leading to cerebral blood flow dysregulation and disruption of the neurovascular unit and the blood-brain barrier, which all may contribute to the onset and progression of dementia and Alzheimer's disease (AD). Particularly, we examine the link between neurovascular dysfunction and neurodegeneration including the effects of AD genetic risk factors on cerebrovascular functions and clearance of Alzheimer's amyloid-β peptide toxin, and the impact of vascular risk factors, environment, and lifestyle on cerebral blood vessels, which in turn may affect synaptic, neuronal, and cognitive functions. Finally, we examine potential experimental treatments for dementia and AD based on the neurovascular model, and discuss some critical questions to be addressed by future studies. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock.

Subclinical carotid atherosclerosis and neurocognitive function in an urban population

BACKGROUND AND AIMS

Examine age, sex, race, and socioeconomic status as modifiers of the association between carotid intimal medial thickness (IMT) and neurocognitive performance in a socioeconomically diverse, biracial, urban, adult population.

METHODS

Participants were 1712 community-dwelling adults (45% men, 56% African-American, 38% below poverty threshold, aged 30-64 years) enrolled in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. Participants underwent initial carotid ultrasonography followed by cognitive testing on up to two occasions over 4 years. Mixed-effects regression analyses were adjusted for demographic, behavioral, and biomedical covariates.

RESULTS

Significant cross-sectional IMT × race × poverty interactions were identified for measures of delayed recall memory, auditory-verbal attention, and working memory. An IMT × race interaction also appeared for auditory-verbal learning. Higher IMT was generally associated with worse cognitive performance, but the disadvantage was most pronounced among those with higher socioeconomic status and white participants. No longitudinal associations were identified.

CONCLUSIONS

Carotid IMT-cognition associations differed as a function of race and socioeconomic status and were most compelling for measures of attention, executive function, and memory. These findings highlight the possibility that subclinical atherosclerosis may be differentially informative as a predictor of cognitive performance among varied demographic subgroups.

Intima-Media Thickness and Cognitive Function in Stroke-Free Middle-Aged Adults: Findings From the Coronary Artery Risk Development in Young Adults Study

BACKGROUND AND PURPOSE

The relationship between carotid artery intima-media thickness (IMT) and cognitive function in midlife remains relatively unexplored. We examined the association between IMT and cognitive function in a middle-aged epidemiological cohort of 2618 stroke-free participants.

METHODS

At the year 20 visit (our study baseline), participants from the Coronary Artery Risk Development in Young Adults study had IMT measured by ultrasound at the common carotid artery. Five years later, participants completed a cognitive battery consisting of the Rey Auditory-Verbal Learning Test of verbal memory, the Digit Symbol Substitution Test of processing speed, and the Stroop test of executive function. We transformed cognitive scores into standardized z scores, with negative values indicating worse performance.

RESULTS

Mean age at baseline was 45.3 years (SD, 3.6). Greater IMT (per 1 SD difference of 0.12 mm) was significantly associated with worse performance on all cognitive tests (z scores) in unadjusted linear regression models (verbal memory, -0.16; 95% confidence interval [CI], -0.20 to -0.13; processing speed, -0.23; 95% CI, -0.27 to -0.19; and executive function, -0.17; 95% CI, -0.20 to -0.13). In models adjusted for sociodemographics and vascular risk factors that lie earlier in the causal pathway, greater IMT remained negatively associated with processing speed (-0.06; 95% CI, -0.09 to -0.02; P, 0.003) and borderline associated with executive function (-0.03; 95% CI, -0.07 to 0.00; P, 0.07) but not with verbal memory.

CONCLUSIONS

We observed an association between greater IMT and worse processing speed-a key component of cognitive functioning-at middle age above and beyond traditional vascular risk factors. Efforts targeted at preventing early stages of atherosclerosis may modify the course of cognitive aging.

Subclinical atherosclerosis and subsequent cognitive function

OBJECTIVE

To examine the relationship between measures of subclinical atherosclerosis and subsequent cognitive function.

METHOD

Participants from the Dallas Heart Study (DHS), a population-based multiethnic study of cardiovascular disease pathogenesis, were re-examined 8 years later (DHS-2) with the Montreal Cognitive Assessment (MoCA); N = 1904, mean age = 42.9, range 8-65. Associations of baseline measures of subclinical atherosclerosis (coronary artery calcium, abdominal aortic plaque, and abdominal aortic wall thickness) with MoCA scores measured at follow-up were examined in the group as a whole and in relation to age and ApoE4 status.

RESULTS

A significant linear trend of successively lower MoCA scores with increasing numbers of atherosclerotic indicators was observed (F(3, 1150) = 5.918, p = .001). CAC was weakly correlated with MoCA scores (p = .047) and MoCA scores were significantly different between participants with and without CAC (M = 22.35 vs 23.69, p = 0.038). With the exception of a small association between abdominal AWT and MoCA in subjects over age 50, abdominal AWT and abdominal aortic plaque did not correlate with MoCA total score (p ≥ .052). Cognitive scores and atherosclerosis measures were not impacted by ApoE4 status (p ≥ .455).

CONCLUSION

In this ethnically diverse population-based sample, subclinical atherosclerosis was minimally associated with later cognitive function in middle-aged adults.

The role of carotid intima-media thickness in predicting longitudinal cognitive function in an older adult cohort

BACKGROUND AND PURPOSE

Carotid atherosclerosis is a risk factor for cerebrovascular disease in older adults. Although age-related cognitive decline has been associated with cerebrovascular disease, not much is known about the consequences of carotid atherosclerosis on longitudinal cognitive function. This study examines the longitudinal relationship between atherosclerosis and cognition in a sample of non-demented older subjects using baseline measurements of carotid intima media thickness (CIMT) and annual cognitive measures of executive function (EXEC) and verbal memory (MEM).

METHODS

Baseline measurements included CIMT derived from B-mode carotid artery ultrasound, structural T1-weighted images of white matter hypointensities (WMH), white matter lesions (WML), and cerebral infarct. Hypertension, low-density lipoprotein (LDL), diabetes, and waist to hip ratios (WHR) were included as covariates in our models to control for cerebrovascular risks and central adiposity. Annual composite scores of EXEC and MEM functions were derived from item response theory. Linear mixed models were used to model longitudinal cognitive change.

RESULTS

A significant inverse relationship was found between baseline CIMT and annual EXEC score, but not annual MEM score. Subjects included in the highest 4th quartile of CIMT showed a rate of annual decline in EXEC score that was significant relative to subjects in lower quartile groups (p<0.01). The relationship between the 4th quartile of CIMT and annual EXEC score remained significant after independently adjusting for imaging measures of white matter injury and cerebral infarct.

CONCLUSIONS

Older adult subjects with the highest index of CIMT showed an annual decline in EXEC scores that was significant relative to subjects with lower quartile measurements of CIMT, independent of our measures of white matter injury and cerebral infarct. Our findings suggest that elevated measures of CIMT may mark an atherosclerotic state, resulting in a decline in executive function and not memory in non-demented older adults.

Influence of carotid artery stenting on cognition of elderly patients with severe stenosis of the internal carotid artery

Background

The aim of this study was to investigate the influence of carotid artery stenting (CAS) on the cognition and quality of life of elderly patients with severe stenosis of the internal carotid artery.

Material/Methods

65 elderly patients with symptomatic severe stenosis of internal carotid artery were recruited into 2 groups: the pharmacotherapy group (n=29) and the CAS group (n=36). Before surgery and 1, 3, 6, and 12 months after surgery, Montreal cognitive assessment (MoCA) was used for the evaluation of cognition and WHOQOL-BREF was used for the assessment of quality of life.

Results

At 12 months after surgery, total MoCA score and WHOQOL-BREF score in the pharmacotherapy group was significantly reduced when compared with those before surgery (P<0.05). In the CAS group, the total MoCA score, scores of attention and delayed recall, and WHOQOL-BREF score increased significantly at different time points after surgery when compared with those before surgery (P<0.05). Moreover, in CAS group, the MoCA score and WHOQOL-BREF markedly increased gradually over time (P<0.05). Compared with the pharmacotherapy group, cognition and quality of life in the CAS group were improved dramatically during the follow-up period (P<0.05).

Conclusions

Severe stenosis of the internal carotid artery is a cause of cognition impairment, and CAS may improve cognition and quality of life.