Framingham Stroke Risk Profile is related to cerebral small vessel disease progression and lower cognitive performance in patients with hypertension

Methods of a Study to Assess the Contribution of Cerebral Small Vessel Disease and Dementia Risk Alleles to Racial Disparities in Vascular Cognitive Impairment and Dementia

Background Non-Hispanic Black adults have a higher proportion of vascular cognitive impairment and Alzheimer's disease and related dementias compared with non-Hispanic White adults that may be due to differences in the burden of cerebral small vessel disease and risk alleles for Alzheimer's disease and related dementias. We describe here the methods of an ancillary study to the REGARDS (Reason for Geographic and and Racial Difference in Stroke) study, which will examine the role of magnetic resonance imaging markers of cerebral small vessel disease and vascular as well as genetic risk factors for Alzheimer's disease and related dementias in racial disparity in the prevalence and trajectory of vascular cognitive impairment and dementia in non-Hispanic White and non-Hispanic Black participants. Methods In participants with no prior history of stroke who had an incident stroke or transient ischemic attack after enrollment in the study, magnetic resonance imaging scans will be evaluated using the Standards for Reporting Vascular Changes on Neuroimaging international consensus criteria and automated analysis pipelines for quantification of cerebral small vessel disease. Participants will be genotyped for APOE ε4 and TREM2 risk alleles for Alzheimer's disease and related dementias. The 6-item screener will define global cognitive function and be the primary cognitive outcome. Conclusions With at least 426 non-Hispanic Black and 463 non-Hispanic White participants who have at least 2 prior and 2 poststroke or transient ischemic attack cognitive assessments, we will have at least 80% power to detect a minimum effect size of 0.09 SD change in Z score, with correction for as many as 20 tests (ie, at P<0.0025, after adjusting for up to 20 covariates) for cognitive decline.

The value of mobile magnetic resonance imaging in early warning for stroke: A prospective case-control study

Aims

To evaluate the predictive value of mobile magnetic resonance imaging (MRI) in screening stroke.

Methods

This was a prospective case-control study performed on healthy residents over 40 years old in remote rural areas of northern China between May 2019 and May 2020. Multivariate logistic regression and receiver operator characteristic curve (ROC) analysis were used to evaluate the screening model.

Results

A total of 1,224 patients (500 [40.8%] men) enrolled, including 56 patients who suffered from stroke (aged 64.05 ± 7.27). The individuals who developed stroke were significantly older (P < 0.001), had a significantly higher occurrence of heart disease (P = 0.015), diabetes (P = 0.005), dyslipidemia (P = 0.009), and significantly increased waist circumference (P = 0.02), systolic blood pressure (SBP) (P = 0.003), glycosylated hemoglobin (HbA1c) level (P = 0.007), triglyceride (TG) level (P = 0.025), low density lipoprotein cholesterol (LDL-c) level (P = 0.04), and homocysteine (HCY) level (P < 0.001). Multivariate logistic regression analysis showed that age (OR = 1.055, 95% CI: 1.017–1.094, P = 0.004), HCY (OR = 1.029, 95% CI: 1.012–1.047, P = 0.001) and mobile MRI (OR = 4.539, 95% CI: 1.726–11.939, P = 0.002) were independently associated with stroke. The area under the curve (AUC) of the combined model including national screening criteria, mobile MRI results, and stroke risk factors was 0.786 (95% CI: 0.721–0.851), with a sensitivity of 69.6% and specificity of 80.4%.

Conclusion

Mobile MRI can be used as a simple and easy means to screen stroke.

Study on the Interaction between the Characteristics of Retinal Microangiopathy and Risk Factors for Cerebral Small Vessel Disease

Objective

This study was designed to explore the characteristics of retinal microangiopathy in patients with cerebral small vessel disease (CSVD) and clarify its interaction with the risk factors for CSVD.

Methods

Sixty patients with CSVD and 15 healthy individuals were enrolled. Demographic data, risk factors, and medical history were recorded, and magnetic resonance imaging was performed to detect and analyze the characteristics of retinal microangiopathy in the two groups. The interaction among retinal microangiopathy, vascular risk factors, and total imaging load of CSVD was compared.

Results

(1) Hypertension, standard deviation of systolic blood pressure (SBPSD), standard deviation of blood glucose (SDBG), and atherogenic index of plasma (AIP) were independent vascular risk factors for CSVD. (2) Statistically significant differences in hypertension, SBPSD, SDBG, and AIP were observed between the two groups in terms of the total imaging burden of CSVD (p < 0.05). (3) Multivariate logistic linear regression showed that CSVD was associated with a wider central retinal vein equivalent (CRVE) (p = 0.015), a smaller arteriole-to-venule ratio (AVR) (p = 0.001), and a higher incidence of vessel tortuosity (p = 0.027). (4) When the total imaging burden of CSVD ranges from 0 to 4 points, the CRVE is larger, the AVR is smaller, and the incidence of vascular tortuosity is higher, with a statistically significant difference (p < 0.05). (5) The characteristics of retinal microangiopathy were correlated with hypertension, SBPSD, SDBG, and AIP (p < 0.05). (6) An association was observed between the characteristics of retinal microangiopathy and vascular risk factors and the total imaging burden of CSVD (p < 0.05).

Conclusions

(1) Hypertension, SBP variability, BG fluctuation, and AIP are independent vascular risk factors for CSVD. (2) Retinal microvessels are changed in patients with CSVD, and venous dilatation, decreased arteriovenous ratio, and vascular tortuosity are the main characteristics of the disease. (3) The characteristics of retinal microangiopathy are interactively correlated with the total imaging load and risk factors for CSVD and can be used as indicators of the severity of CSVD.

Patterns of progression of cerebral small vessel disease markers in older adults of Amerindian ancestry: a population-based, longitudinal prospective cohort study

BACKGROUND

Progression of cerebral small vessel disease (cSVD) markers has been studied in different races/ethnic groups. However, information from individuals of Amerindian ancestry is lacking. We sought to evaluate progression patterns of cSVD markers in community-dwelling older adults of Amerindian ancestry.

METHODS

Following a longitudinal prospective study design, participants of the Atahualpa Project Cohort aged ≥ 60 years received a baseline brain MRI and clinical interviews. Those who also received a brain MRI at the end of the study were included. Poisson regression models were fitted to assess cSVD markers progression according to their baseline load after a median follow-up of 6.5 ± 1.4 years. Logistic regression models were fitted to assess interrelations in the progression of the different cSVD markers at the end of the study.

RESULTS

The study included 263 individuals (mean age: 65.7 ± 6.2 years). Progression of white matter hyperintensities (WMH) was noticed in 103 (39%) subjects, cerebral microbleeds in 25 (12%), lacunes in 12 (5%), and enlarged basal ganglia-perivascular spaces (BG-PVS) in 56 (21%). Bivariate Poisson regression models showed significant associations between WMH severity at baseline and progression of WMH and enlarged BG-PVS. These associations became non-significant in multivariate models adjusted for clinical covariates. Logistic regression models showed interrelated progressions of WMH, cerebral microbleeds and enlarged BG-PVS. The progression of lacunes was independent.

CONCLUSIONS

Patterns of cSVD marker progression in this population of Amerindians are different than those reported in other races/ethnic groups. The independent progression of lacunes suggests different pathogenic mechanisms with other cSVD markers.

Breast Arterial Calcification Is Not Associated with Mild Cognitive Impairment or Incident All-Cause Dementia Among Postmenopausal Women: The MINERVA Study

Background: Since vascular risk factors are implicated in cognitive decline, and breast arterial calcification (BAC) is related to vascular risk, we postulated that BAC may be associated with cognitive impairment and dementia. Methods: We used a multiethnic cohort of 3,913 asymptomatic women 60-79 years of age recruited after mammography screening at a large health plan in 2012-2015. A BAC mass score (mg) was derived from digital mammograms. Cognitive function was measured at baseline using the Montreal Cognitive Assessment (MoCA) and incident all-cause dementia (n = 49 events; median follow-up = 5.6 years) were ascertained with validated ICD-9 and ICD-10 codes. We used cross-sectional linear regression of MoCA scores on BAC, then multinomial logistic regression predicting mild cognitive impairment not progressing to dementia and incident all-cause dementia and, finally, Cox regression of incident all-cause dementia. Results: No association by linear regression was found between MoCA scores and BAC presence in unadjusted or adjusted analysis. Women with severe (upper tertile) BAC had a MoCA score lower by 0.58 points (standard error [SE] = 0.18) relative to women with no BAC. However, this difference disappeared after multivariate adjustment. No significant associations were found in multinomial logistic regression for either BAC presence or gradation in unadjusted or adjusted analysis. No significant associations were found between BAC presence with incident all-cause dementia (fully adjusted hazard ratio = 0.74; 95% confidence interval: 0.39-1.39). Likewise, no significant association with incident all-cause dementia was noted for BAC gradation. Conclusions: Our results do not support the hypothesis that BAC presence or gradation may contribute to cognitive impairment or development of all-cause dementia.

Cognitive Reserve Over the Lifespan: Neurocognitive Implications for Aging With HIV

Approximately 59% of adults living with HIV experience HIV-associated neurocognitive disorder, a collection of symptoms and cognitive deficits in various cognitive domains. As the HIV population ages, the prevalence and severity of such cognitive deficits are expected to grow. Understanding how these cognitive deficits manifest is important for nurses and health care providers. This article provides an overview of cognitive reserve and evidence of how it is compromised by HIV, aging, and individual characteristics. Within this context of cognitive reserve, the role of neuroinflammation, neurotoxicity, substance use, comorbidities, depression and anxiety, social isolation, and sedentary lifestyle is reviewed. From this, strategies used to address cognitive deficits are provided, including topics such as psychostimulants, cognitive training, multimodal lifestyle interventions, and compensation strategies. Scenarios of successful and unsuccessful cognitive aging are presented to provide a lifespan perspective of cognitive reserve. Implications for clinical practice and research are provided, as it relates to aging.

Association of midlife stroke risk with structural brain integrity and memory performance at older ages: a longitudinal cohort study

Cardiovascular health in midlife is an established risk factor for cognitive function later in life. Knowing mechanisms of this association may allow preventative steps to be taken to preserve brain health and cognitive performance in older age. In this study, we investigated the association of the Framingham stroke-risk score, a validated multifactorial predictor of 10-year risk of stroke, with brain measures and cognitive performance in stroke-free individuals. We used a large (N = 800) longitudinal cohort of community-dwelling adults of the Whitehall II imaging sub-study with no obvious structural brain abnormalities, who had Framingham stroke risk measured five times between 1991 and 2013 and MRI measures of structural integrity, and cognitive function performed between 2012 and 2016 [baseline mean age 47.9 (5.2) years, range 39.7-62.7 years; MRI mean age 69.81 (5.2) years, range 60.3-84.6 years; 80.6% men]. Unadjusted linear associations were assessed between the Framingham stroke-risk score in each wave and voxelwise grey matter density, fractional anisotropy and mean diffusivity at follow-up. These analyses were repeated including socio-demographic confounders as well as stroke risk in previous waves to examine the effect of residual risk acquired between waves. Finally, we used structural equation modelling to assess whether stroke risk negatively affects cognitive performance via specific brain measures. Higher unadjusted stroke risk measured at each of the five waves over 20 years prior to the MRI scan was associated with lower voxelwise grey and white matter measures. After adjusting for socio-demographic variables, higher stroke risk from 1991 to 2009 was associated with lower grey matter volume in the medial temporal lobe. Higher stroke risk from 1997 to 2013 was associated with lower fractional anisotropy along the corpus callosum. In addition, higher stroke risk from 2012 to 2013, sequentially adjusted for risk measured in 1991-94, 1997-98 and 2002-04 (i.e. 'residual risks' acquired from the time of these examinations onwards), was associated with widespread lower fractional anisotropy, and lower grey matter volume in sub-neocortical structures. Structural equation modelling suggested that such reductions in brain integrity were associated with cognitive impairment. These findings highlight the importance of considering cerebrovascular health in midlife as important for brain integrity and cognitive function later in life (ClinicalTrials.gov Identifier: NCT03335696).

Revised Framingham Stroke Risk Profile: Association with Cognitive Status and MRI-Derived Volumetric Measures

BACKGROUND

The Framingham Stroke Risk Profile (FSRP) was created in 1991 to estimate 10-year risk of stroke. It was revised in 2017 (rFSRP) to reflect the modern data on vascular risk factors and stroke risk.

OBJECTIVE

This study examined the association between the rFSRP and cognitive and brain aging outcomes among participants from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS).

METHODS

Cross-sectional rFSRP was computed at baseline for 19,309 participants (mean age = 72.84, SD = 8.48) from the NACC-UDS [9,697 (50.2%) normal cognition, 4,705 (24.4%) MCI, 4,907 (25.4%) dementia]. Multivariable linear, logistic, or ordinal regressions examined the association between the rFSRP and diagnostic status, neuropsychological test performance, CDR® Sum of Boxes, as well as total brain volume (TBV), hippocampal volume (HCV), and log-transformed white matter hyperintensities (WMH) for an MRI subset (n = 1,196). Models controlled for age, sex, education, racial identity, APOEɛ4 status, and estimated intracranial volume for MRI models.

RESULTS

The mean rFSRP probability was 10.42% (min = 0.50%, max = 95.71%). Higher rFSRP scores corresponded to greater CDR Sum of Boxes (β= 0.02, p = 0.028) and worse performance on: Trail Making Test A (β= 0.05, p < 0.001) and B (β= 0.057, p < 0.001), and Digit Symbol (β= -0.058, p < 0.001). Higher rFSRP scores were associated with increased odds for a greater volume of log-transformed WMH (OR = 1.02 per quartile, p = 0.015). No associations were observed for diagnosis, episodic memory or language test scores, HCV, or TBV.

CONCLUSION

These results support the rFSRP as a useful metric to facilitate clinical research on the associations between cerebrovascular disease and cognitive and brain aging.

The Altered Reconfiguration Pattern of Brain Modular Architecture Regulates Cognitive Function in Cerebral Small Vessel Disease

Background: Cerebral small vessel disease (SVD) is a common cause of cognitive dysfunction. However, little is known whether the altered reconfiguration pattern of brain modular architecture regulates cognitive dysfunction in SVD.

Methods: We recruited 25 cases of SVD without cognitive impairment (SVD-NCI) and 24 cases of SVD with mild cognitive impairment (SVD-MCI). According to the Framingham Stroke Risk Profile, healthy controls (HC) were divided into 17 subjects (HC-low risk) and 19 subjects (HC-high risk). All individuals underwent resting-state functional magnetic resonance imaging and cognitive assessments. Graph-theoretical analysis was used to explore alterations in the modular organization of functional brain networks. Multiple regression and mediation analyses were performed to investigate the relationship between MRI markers, network metrics and cognitive performance.

Results: We identified four modules corresponding to the default mode network (DMN), executive control network (ECN), sensorimotor network and visual network. With increasing vascular risk factors, the inter- and intranetwork compensation of the ECN and a relatively reserved DMN itself were observed in individuals at high risk for SVD. With declining cognitive ability, SVD-MCI showed a disrupted ECN intranetwork and increased DMN connection. Furthermore, the intermodule connectivity of the right inferior frontal gyrus of the ECN mediated the relationship between periventricular white matter hyperintensities and visuospatial processing in SVD-MCI.

Conclusions: The reconfiguration pattern of the modular architecture within/between the DMN and ECN advances our understanding of the neural underpinning in response to vascular risk and SVD burden. These observations may provide novel insight into the underlying neural mechanism of SVD-related cognitive impairment and may serve as a potential non-invasive biomarker to predict and monitor disease progression.

Vascular burden and APOE ε4 are associated with white matter microstructural decline in cognitively normal older adults

White matter microstructure can be measured with diffusion tensor imaging (DTI). While increasing age is a predictor of white matter (WM) microstructure changes, roles of other possible modifiers, such as cardiovascular risk factors, APOE ε4 allele status and biological sex have not been clarified. We investigated 665 cognitively normal participants from the Baltimore Longitudinal Study of Aging (age 50-95, 56.7% female) with a total of 1384 DTI scans. WM microstructure was assessed by fractional anisotropy (FA) and mean diffusivity (MD). A vascular burden score was defined as the sum of five risk factors (hypertension, obesity, elevated cholesterol, diabetes and smoking status). Linear mixed effects models assessed the association of baseline vascular burden on baseline and on rates of change of FA and MD over a mean follow-up of 3.6 years, while controlling for age, race, and scanner type. We also compared DTI trajectories in APOE ε4 carriers vs. non-carriers and men vs. women. At baseline, higher vascular burden was associated with lower FA and higher MD in many WM structures including association, commissural, and projection fibers. Higher baseline vascular burden was also associated with greater longitudinal decline in FA in the hippocampal part of the cingulum and the fornix (crus)/stria terminalis and splenium of the corpus callosum, and with greater increases in MD in the splenium of the corpus callosum. APOE ε4 carriers did not differ from non-carriers in baseline DTI metrics but had greater decline in FA in the genu and splenium of the corpus callosum. Men had higher FA and lower MD in multiple WM regions at baseline but showed greater increase in MD in the genu of the corpus callosum. Women showed greater decreases over time in FA in the gyrus part of the cingulum, compared to men. Our findings show that modifiable vascular risk factors (1) have a negative impact on white matter microstructure and (2) are associated with faster microstructural deterioration of temporal WM regions and the splenium of the corpus callosum in cognitively normal adults. Reducing vascular burden in aging could modify the rate of WM deterioration and could decrease age-related cognitive decline and impairment.

A study on role and mechanism of TLR4/NF-κB pathway in cognitive impairment induced by cerebral small vascular disease

OBJECTIVE

To investigate the role and potential mechanism of Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway in cognitive impairment induced by cerebral small vascular disease (CSVD), so as to provide a reference for the clinical treatment of CSVD-induced cognitive impairment.

METHODS

Mice with TLR4 gene knockout (n = 20) and those with wild-type TLR4 gene (n = 40) aged 8-10 weeks old were divided into blank control group (Control group, n = 20), wild-type + CSVD group (WT + CSVD group, n = 20) and TLR4 gene knockout + CSVD group (TLR4 KO + CSVD group, n = 20). Allogeneic thrombosis (particle diameter: 50-70 mm) was injected to the mouse's external carotid artery to create a model of learning and memory dysfunction. Step-down test and Y-type maze test were utilized to examine the learning and memory abilities of the mice. Reverse transcription-polymerase chain reaction (RT-PCR) and immunoblotting techniques were adopted to measure the levels of apoptosis-related genes [B-cell lymphoma/leukemia-2 (Bcl-2), Bcl-2-associated X protein (Bax), C-caspase-3 and T-caspase-3] in the brain tissues of mice. Terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method was applied to detect the apoptosis of neuronal cells in the brain tissues. Meanwhile, the levels of oxidative stress markers, including superoxide dismutase (SOD), gp91 and malondialdehyde (MDA), were measured. Finally, the expression level of TLR4/NF-κB pathway was detected.

RESULTS

The latency in the step-down test in the WT + CSVD group was remarkably longer than that in the Control group, and the number of errors was evidently larger than that in the Control group (p < 0.05). At the same time, in the WT + CSVD group, the expression levels of pro-apoptotic genes Bax and C-caspase-3 were up-regulated markedly, while the expression level of anti-apoptotic gene Bcl-2 declined notably (p < 0.05). TUNEL results showed that the number of apoptotic cells in the brain tissues in the WT + CSVD group was about 12 times that in the Control group (p < 0.05). Meanwhile, the SOD expression level was lowered, and the MDA expression level was elevated in the brain tissues in the WT + CSVD group. In addition, the TLR4/NF-κB pathway was prominently activated in the mice in the WT + CSVD group (p < 0.05). After TLR4 gene knockout, the cognitive functions of the mice were improved markedly, and the apoptosis of neuronal cells and oxidative stress in the brain tissues were suppressed significantly in the meantime. Moreover, the activation of the TLR4/NF-κB signaling pathway was also inhibited.

CONCLUSION

The TLR4/NF-κB pathway is involved in the occurrence and development of CSVD-induced cognitive impairment through regulating oxidative stress and cell apoptosis.

The importance of comorbidities in ischemic stroke: Impact of hypertension on the cerebral circulation

Comorbidities are a hallmark of stroke that both increase the incidence of stroke and worsen outcome. Hypertension is prevalent in the stroke population and the most important modifiable risk factor for stroke. Hypertensive disorders promote stroke through increased shear stress, endothelial dysfunction, and large artery stiffness that transmits pulsatile flow to the cerebral microcirculation. Hypertension also promotes cerebral small vessel disease through several mechanisms, including hypoperfusion, diminished autoregulatory capacity and localized increase in blood-brain barrier permeability. Preeclampsia, a hypertensive disorder of pregnancy, also increases the risk of stroke 4-5-fold compared to normal pregnancy that predisposes women to early-onset cognitive impairment. In this review, we highlight how comorbidities and concomitant disorders are not only risk factors for ischemic stroke, but alter the response to acute ischemia. We focus on hypertension as a comorbidity and its effects on the cerebral circulation that alters the pathophysiology of ischemic stroke and should be considered in guiding future therapeutic strategies.

Cerebral Microbleeds in Advanced Dementia: Clinical and Pathological Correlates

OBJECTIVE

We conducted a longitudinal study to explore the clinical and pathological correlates of cerebral microbleeds (CMBs) in institutionalized patients with dementia.

METHODS

Clinical and magnetic resonance imaging (MRI) data were extracted from 182 nursing home patients (mean age [standard deviation]: 81.3 [6.9], 78.0% female, and 83.4% moderate to severe dementia), which were divided according to the CMBs number and location. One-year follow-up data were obtained from 153 patients, and postmortem pathological diagnosis was available in 40 patients.

RESULTS

Cerebral microbleeds were observed in 42.9% of patients and were associated with MRI ischemic lesions ( P < .0005). In the adjusted analysis, lobar CMB predicted worsening of parkinsonism (standardized β: 0.43) and gait (standardized β: 0.24). A pathological diagnosis of Alzheimer's disease was less frequent in the brains of patients with lobar and deep CMB (33.3% vs 85.3%; P < .05).

CONCLUSION

Cerebral microbleeds were linked to cerebrovascular disease and predicted motor deterioration in institutionalized people with advanced dementia.

Plasma brain natriuretic peptide is a biomarker for screening ischemic cerebral small vessel disease in patients with hypertension

Plasma brain natriuretic peptide (BNP), a diagnostic marker of cardiovascular diseases, has been previously linked to cerebrovascular diseases. Our goal was to determine whether plasma BNP level is helpful for identifying high-risk individuals who are likely to present with the 3 main subtypes of cerebral small vessel diseases (CSVDs), namely, white matter lesions, lacunar infarcts, and cerebral microbleeds, on magnetic resonance imaging (MRI) in patients with hypertension.Three hundred forty-six consecutive hypertensive patients presenting at our cardiology or neurology clinic were investigated. Plasma BNP level was measured by chemiluminescent microparticle immunoassay. The presence of CSVD was assessed by 1.5-T brain MRI. Multivariate linear regression was used to determine whether individual or combined MRI-defined CSVD subtypes were associated with BNP level, after adjustment for several covariates.The mean age of patients was 69.1 ± 9.8 years, and 44.2% were female. The highest quartile BNP group was positively associated with advanced age, female sex, clinically manifesting cardiac diseases, and ischemic CSVD (white matter lesions and lacunar infarcts) and no association with cerebral microbleeds. According to multivariate linear regression, white matter lesions [β = 0.722; 95% confidence interval (95% CI), 0.624-0.819] and lacunar infarcts (β = 0.635; 95% CI, 0.508-0.762) were independently associated with BNP level, even after controlling for vascular risk factors and clinically manifesting cardiac diseases. Combined white matter lesions and lacunar infarcts were more strongly associated with BNP level than each subtype alone. With the cutoff value of 106.4 pg/mL, BNP level had a sensitivity, a specificity, and an area under the curve of 95.2%, 64.9%, and 0.799, respectively, for white matter lesions, whereas the values were 143.0 pg/mL, 81.6%, 73.5%, and 0.848, respectively, for lacunar infarcts.Plasma BNP level, which is independently correlated with individual or combined white matter lesions and lacunar infarcts, is a useful molecular marker for identifying ischemic CSVD in patients with hypertension.