Mizagliflozin, a selective SGLT1 inhibitor, improves vascular cognitive impairment in a mouse model of small vessel disease.

Previously, we showed that sodium/glucose cotransporter 1 (SGLT1) participates in vascular cognitive impairment in small vessel disease. We hypothesized that SGLT1 inhibitors can improve the small vessel disease induced-vascular cognitive impairment. We examined the effects of mizagliflozin, a selective SGLT1 inhibitor, and phlorizin, a non-selective SGLT inhibitor, on vascular cognitive impairment in a mouse model of small vessel disease. Small vessel disease was created using a mouse model of asymmetric common carotid artery surgery (ACAS). Two and/or 4 weeks after ACAS, all experiments were performed. Cerebral blood flow (CBF) was decreased in ACAS compared with sham-operated mice. Phlorizin but not mizagliflozin reversed the decreased CBF of ACAS mice. Both mizagliflozin and phlorizin reversed the ACAS-induced decrease in the latency to fall in a wire hang test of ACAS mice. Moreover, they reversed the ACAS-induced longer escape latencies in the Morris water maze test of ACAS mice. ACAS increased SGLT1 and proinflammatory cytokine gene expressions in mouse brains and phlorizin but not mizagliflozin normalized all gene expressions in ACAS mice. Hematoxylin/eosin staining demonstrated that they inhibited pyknotic cell death in the ACAS mouse hippocampus. In PC12HS cells, IL-1ß increased SGLT1 expression and decreased survival rates of cells. Both mizagliflozin and phlorizin increased the survival rates of IL-1ß-treated PC12HS cells. These results suggest that mizagliflozin and phlorizin can improve vascular cognitive impairment through the inhibition of neural SGLT1 and phlorizin also does so through the improvement of CBF in a mouse model of small vessel disease.

Association between infectious burden and cerebral microbleeds: a pilot cross-sectional study.

OBJECTIVE: Cerebral microbleeds (CMBs) is a subtype of cerebral small vessel disease. Their underlying pathogenesis remains unclear. The aim of this study was to investigate the association between infectious burden (IB) and CMBs. METHODS: Seven hundred and seventy-three consecutive patients who were hospitalized in the Department of Neurology in General Hospital of Western Theater Command without severe neurological symptoms were recruited and selected in this pilot cross-sectional study. CMBs were assessed using the susceptibility-weighted imaging sequence of magnetic resonance imaging. Immunoglobulin G antibodies against common pathogens, including herpes simplex virus (HSV)-1, HSV-2, cytomegalovirus (CMV), Chlamydia pneumoniae (C. pneumoniae), Mycoplasma pneumoniae (M. pneumoniae), Epstein-Barr virus (EBV), Helicobacter pylori (HP), and Borrelia burgdorferi (B. burgdorferi), were measured by commercial ELISA assays. IB was defined as a composite serologic measure of exposure to these common pathogens. RESULTS: Patients with and without CMBs were defined as the CMBs group (n = 76) and the non-CMBs group (n = 81), respectively. IB was significantly different between the CMBs and non-CMBs groups. After adjusted for other risk factors, the increased IB was independently associated with the presence of CMBs (P = 0.031, OR = 3.00, 95% CI [1.11-8.15]). IB was significantly positively associated with the number of CMBs (Spearman ρ = 0.653, P < 0.001). The levels of serum inflammatory markers were significantly different between the CMBs and non-CMBs groups and among the categories of IB. INTERPRETATION: IB consisting of HSV-1, HSV-2, CMV, C. pneumoniae, M. pneumoniae, EBV, HP, and B. burgdorferi was associated with CMBs. All the findings suggested that pathogen infection could be involved in the pathogenesis of CMBs.

Is microvascular dysfunction a systemic disorder with common biomarkers found in the heart, brain, and kidneys? - A scoping review.

Although microvascular dysfunction (MVD) has been well characterized in individual organs as different disease entities, clinical evidence is mounting in support of an underlying systemic process. To address this hypothesis, we systematically searched PubMed and Medline for studies in adults published between 2014 and 2019 that measured blood biomarkers of MVD in three vital organs i.e. brain, heart, and the kidney. Of the 9706 unique articles 321 met the criteria, reporting 49 biomarkers of which 16 were common to the three organs. Endothelial dysfunction, inflammation including reactive oxidation, immune activation, and coagulation were the commonly recognized pathways. Triglyceride, C-reactive protein, Cystatin C, homocysteine, uric acid, IL-6, NT-proBNP, thrombomodulin, von Willebrand Factor, and uric acid were increased in MVD of all three organs. In contrast, vitamin D was decreased. Adiponectin, asymmetric dimethylarginine, total cholesterol, high-density and low-density cholesterol were found to be variably increased or decreased in studies. We review the pathways underlying MVD in the three organs and summarize evidence supporting its systemic nature. This scoping review informs clinicians and researchers in the multi-system manifestation of MVD. Future work should focus on longitudinal investigations to evaluate the multi-system involvement of this disease.

Day-to-Day Home Blood Pressure Variability is Associated with Cerebral Small Vessel Disease Burden in a Memory Clinic Population.

BACKGROUND: High visit-to-visit blood pressure variability (BPV) has been associated with cognitive decline and cerebral small vessel disease (cSVD), in particular cerebrovascular lesions. Whether day-to-day BPV also relates to cSVD has not been investigated. OBJECTIVE: To investigate the cross-sectional association between day-to-day BPV and total cSVD MRI burden in older memory clinic patients. METHODS: We included outpatients referred to our memory clinic, who underwent cerebral MRI as part of their diagnostic assessment. We determined the validated total cSVD score (ranging from 0-4) by combining four markers of cSVD that were visually rated. Home blood pressure (BP) measurements were performed for one week, twice a day, according to international guidelines. BPV was defined as the within-subject coefficient of variation (CV; standard deviation/mean BP*100). We used multivariable ordinal logistic regression analyses adjusted for age, sex, smoking, diabetes, antihypertensive medication, history of cardiovascular disease, and mean BP. RESULTS: For 82 patients (aged 71.2±7.9 years), mean home BP was 140/79±15/9 mmHg. Dementia and mild cognitive impairment were diagnosed in 46% and 34%, respectively. 78% had one or more markers of cSVD. Systolic CV was associated with cSVD burden (adjusted odds ratio per point increase in CV = 1.29, 95% confidence interval = 1.04-1.60, p = 0.022). There were no differences in diastolic CV and mean BP between the cSVD groups. When we differentiated between morning and evening BP, only evening BPV remained significantly associated with total cSVD burden. CONCLUSION: Day-to-day systolic BPV is associated with cSVD burden in memory clinic patients. Future research should indicate whether lowering BPV should be included in BP management in older people with memory complaints.

Microvascular Dysfunction Is Associated With Worse Cognitive Performance: The Maastricht Study.

Microvascular dysfunction may be associated with worse cognitive performance. Most previous studies did not adjust for important confounders, evaluated only individual measures of microvascular dysfunction, and showed inconsistent results. We evaluated the association between a comprehensive set of measures of microvascular dysfunction and cognitive performance in the population-based Maastricht Study. We used cross-sectional data including 3011 participants (age 59.5±8.2; 48.9% women; 26.5% type 2 diabetes mellitus [oversampled by design]). Measures of microvascular dysfunction included magnetic resonance imaging features of cerebral small vessel disease, plasma biomarkers of microvascular dysfunction, albuminuria, flicker light-induced retinal arteriolar and venular dilation response and heat-induced skin hyperemia. These measures were summarized into a microvascular dysfunction composite score. Cognitive domains assessed were memory, processing speed, and executive function. A cognitive function score was calculated as the sum of the scores on these 3 cognitive domains. The microvascular dysfunction score was associated with a worse cognitive function score (standardized ß, -0.087 [95% CI, -0.127 to -0.047]), independent of age, education level, sex, type 2 diabetes mellitus, smoking, alcohol use, hypertension, total/HDL (high-density lipoprotein) cholesterol ratio, triglycerides, lipid-modifying medication, prior cardiovascular disease, depression and plasma biomarkers of low-grade inflammation. The fully adjusted ß-coefficient of the association between the microvascular dysfunction score and the cognitive function score was equivalent to 2 (range, 1-3) years of aging for each SD higher microvascular dysfunction score. The microvascular dysfunction score was associated with worse memory and processing speed but not with worse executive function. The present study shows that microvascular dysfunction is associated with worse cognitive performance.

CNS small vessel disease: A clinical review.

CNS small vessel disease (CSVD) causes 25% of strokes and contributes to 45% of dementia cases. Prevalence increases with age, affecting about 5% of people aged 50 years to almost 100% of people older than 90 years. Known causes and risk factors include age, hypertension, branch atheromatous disease, cerebral amyloid angiopathy, radiation exposure, immune-mediated vasculitides, certain infections, and several genetic diseases. CSVD can be asymptomatic; however, depending on location, lesions can cause mild cognitive dysfunction, dementia, mood disorders, motor and gait dysfunction, and urinary incontinence. CSVD is diagnosed on the basis of brain imaging biomarkers, including recent small subcortical infarcts, white matter hyperintensities, lacunes, cerebral microbleeds, enlarged perivascular spaces, and cerebral atrophy. Advanced imaging modalities can detect signs of disease even earlier than current standard imaging techniques. Diffusion tensor imaging can identify altered white matter connectivity, and blood oxygenation level-dependent imaging can identify decreased vascular reactivity. Pathogenesis is thought to begin with an etiologically specific insult, with or without genetic predisposition, which results in dysfunction of the neurovascular unit. Uncertainties regarding pathogenesis have delayed development of effective treatment. The most widely accepted approach to treatment is to intensively control well-established vascular risk factors, of which hypertension is the most important. With better understanding of pathogenesis, specific therapies may emerge. Early identification of pathologic characteristics with advanced imaging provides an opportunity to forestall progression before emergence of symptoms.

Comparison Study of ASCO and TOAST Classification System in Chinese Minor Stroke Patients.

BACKGROUND: Precise subtype classification based on underlying pathophysiology is important to prevent recurrent attack in minor stroke patients. A newly developed Atherosclerosis, Small vessel disease, Cardiac source, Others (ASCO) phenotypic classification system aims to characterize patients using different grades of evidence for stroke subtypes. However, this system has not been specifically applied to minor stroke population. In our study, the impact of using the newer ASCO criteria on minor stroke etiologies was investigated, and compared with that of Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification. METHODS: Consecutive patients with minor ischemic stroke (NIHSS ≤3) were assessed and subtyped by the ASCO and TOAST systems. Stroke etiologies were presented and compared. The McNemar test and k statistic were used to analyze the difference and concordance between the 2 algorithms, respectively. RESULTS: A total of 604 first-ever minor stroke patients were analyzed in the present study. Using TOAST classification, large artery atherosclerosis was the most frequent subtype (281, 46.5%), followed by small artery occlusion category (165, 27.3%). When ASCO was applied, 37 different profiles of stroke etiologies were identified. Using grade 1 of evidence, atherosclerosis (A1) was the most frequent subtype (308, 51.0%), followed by small vessel disease (S1, 178, 29.5%). Under consideration of grades 1 and 2, 239 (39.6%) patients were classified into more than 1 category. The ASCO system revealed determined etiologies in 104 of the 137 patients classified to cause undetermined subtype by TOAST classification. Good to very good accordance was observed between ASCO grade 1 and TOAST schemes across etiologic subtypes (κ = 0.719-0.832) except cause undetermined category (κ = 0.470). CONCLUSION: Application of ASCO decreased the proportion of patients assigned to cause undermined category compared to TOAST system. Comprehensive characteristics of ASCO system might be helpful in the personalized therapy or secondary prevention for individual patients in the future.

A Follow-up Study of Cerebral Microbleeds in Patients Who Received Stents for Symptomatic Cerebral Artery Stenosis.

BACKGROUND: The aims of this study were to explore (i) the dynamic changes in cerebral microbleeds (CMBs) in patients with symptomatic cerebral artery stenosis who received endovascular stent-assisted angioplasty and (ii) the risk factors associated with the new incidence of CMBs as well as whether CMBs increased the risk of vascular events in these patients. METHODS: Clinical information and magnetic resonance images were collected on admission and 3 months after endovascular stent-assisted angioplasty. Based on susceptibility-weighted imaging, the patients were divided into groups with or without newly developed CMBs, and between-group differences in risk factors were compared. We also compared whether CMBs increased the risk of vascular events among those patients. RESULTS: Seventy-three patients completed the relevant follow-up examinations. After an average follow-up period of 109 days, 7 (9.6%) patients showed new CMBs. A univariate analysis showed that the number of lacunar infarcts and the increase in systolic blood pressure were higher in patients with new CMBs than in those without new CMBs, and these differences were significant (P = 0.034, P = 0.001). Increased systolic blood pressure was an independent risk factor for developing new CMBs (P = 0.017). CONCLUSIONS: CMBs may be a continuously progressing cerebral small-vessel disease. The newly developed CMBs in patients with intracranial and/or extracranial stents were associated with increased systolic blood pressure but not with the number of baseline CMBs.

Clinical associations of T2-weighted lesion load and lesion location in small vessel disease: Insights from a large prospective cohort study.

BACKGROUND: Subcortical T2-weighted (T2w) lesions are very common in older adults and have been associated with dementia. However, little is known about the strategic lesion distribution and how lesion patterns relate to vascular risk factors and cognitive impairment. AIM: The aim of this study was to analyze the association between T2w lesion load and location, vascular risk factors, and cognitive impairment in a large cohort of older adults. METHODS: 1017 patients participating in a large prospective cohort study (INtervention project on cerebroVAscular disease and Dementia in the district of Ebersberg, INVADE II) were analyzed. Cerebral T2w white matter and deep grey matter lesions, the so-called white matter hyperintensities (WMHs), were outlined semi-automatically on fluid attenuated inversion recovery images and normalized to standard stereotaxic space (MNI152) by non-linear registration. Patients were assigned to either a low-risk or a high-risk group. The risk assessment considered ankle brachial index, intima media thickness, carotid artery stenosis, atrial fibrillation, previous cerebro-/cardiovascular events and peripheral artery disease as well as a score based on cholesterol levels, blood pressure and smoking. Separate lesion distributions were obtained for the two risk groups and compared using voxel-based lesion-symptom mapping. Moreover, we assessed the relation between lesion location and cognitive impairment (demographically adjusted z-scores of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery Plus, CERAD-NAB Plus) using voxel-based statistics (α = 0.05). RESULTS: A total of 878 out of 1017 subjects (86%) had evaluable MRI data and were included in the analyses (mean age: 68.2 ±â€¯7.6 years, female: 515). Patients in the high-risk group were characterized by a significantly higher age, a higher proportion of men, a higher lesion load (p < 0.001), and a worse performance in some of the cognitive subdomain scores (p < 0.05). Voxels with significant associations to the subjects' cerebrovascular risk profiles were mainly found at locations of the corpus callosum, superior corona radiata, superior longitudinal fasciculus, internal and external capsule, and putamen. While several cognitive domains have shown significant associations with the participants' total lesion burden (p < 0.05), no focal WMH locations were found to be associated with cognitive impairment. CONCLUSION: Age, gender, several cognitive scores, and WMH lesion load were shown to be significantly associated with vascular risk factors in a population of older, but cognitively preserved adults. Vascular risk factors seem to promote lesion formation most severely at well-defined locations. While lesion load showed weak associations to some cognitive scores, no focal locations causing specific cognitive disturbances were identified in this large cohort of older adults.

Left ventricular ejection fraction is associated with small vessel disease in ischaemic stroke patients.

BACKGROUND AND PURPOSE: The purpose was to evaluate the association between the left ventricular ejection fraction (LVEF) and cerebral small vessel disease (cSVD) in ischaemic stroke patients. METHODS: Consecutive first-ever ischaemic stroke patients between 2010 and 2013 were included. White matter hyperintensity (WMH) volumes were rated using both the Fazekas score and quantitative methods on fluid-attenuated inversion recovery images. As spectra of cSVD, lacunes, cerebral microbleeds (CMBs) and enlarged perivascular spaces (EPVSs) were also evaluated. To assess the dose-response relationship between LVEF and cSVD, the burdens of each radiological marker and the total cSVD score were rated. RESULTS: A total of 841 patients were included [median WMH volume 2.98 (1.22-10.50) ml; the frequencies of lacunes, CMBs and moderate to severe EPVSs were 38%, 31% and 35%, respectively]. In the multivariate analysis about predictors of WMH volumes, the LVEF (B = -0.052, P < 0.001) remained significant after adjusting for confounders. LVEF was also a predictor of lacunes [adjusted odds ratio (aOR) 0.978, P = 0.012], CMBs (aOR = 0.96, P < 0.001) and moderate to severe EPVSs (aOR = 0.94, P < 0.001) after adjusting for their confounders. The LVEF values were negatively correlated with the burdens of lacunes (P = 0.026), CMBs (P < 0.001) and EPVSs (P = 0.002). The total cSVD score also showed a negative association with LVEF in a dose-response manner (P < 0.001). CONCLUSIONS: The burden of cSVD is negatively correlated with the LVEF in a dose-response manner. Our results suggest clues for further studies about determining the pathophysiology of cSVD.

Reversal of endothelial dysfunction reduces white matter vulnerability in cerebral small vessel disease in rats.

Dementia is a major social and economic problem for our aging population. One of the most common of dementia in the elderly is cerebral small vessel disease (SVD). Magnetic resonance scans of SVD patients typically show white matter abnormalities, but we do not understand the mechanistic pathological link between blood vessels and white matter myelin damage. Hypertension is suggested as the cause of sporadic SVD, but a recent alternative hypothesis invokes dysfunction of the blood-brain barrier as the primary cause. In a rat model of SVD, we show that endothelial cell (EC) dysfunction is the first change in development of the disease. Dysfunctional ECs secrete heat shock protein 90α, which blocks oligodendroglial differentiation, contributing to impaired myelination. Treatment with EC-stabilizing drugs reversed these EC and oligodendroglial pathologies in the rat model. EC and oligodendroglial dysfunction were also observed in humans with early, asymptomatic SVD pathology. We identified a loss-of-function mutation in ATPase11B, which caused the EC dysfunction in the rat SVD model, and a single-nucleotide polymorphism in ATPase11B that was associated with white matter abnormalities in humans with SVD. We show that EC dysfunction is a cause of SVD white matter vulnerability and provide a therapeutic strategy to treat and reverse SVD in the rat model, which may also be of relevance to human SVD.

IL-6, PF-4, sCD40 L, and homocysteine are associated with the radiological progression of cerebral small-vessel disease: a 2-year follow-up study.

BACKGROUND: Endothelial dysfunction (ED) is involved in the pathogenesis of cerebral small vessel disease (SVD), however, it is not clear if specific biomarkers related to ED are associated with radiological progression of SVD. METHODS: A single-center, prospective cohort study was conducted among consecutive, adult patients with SVD. Logistic regression was used to analyze the association of each baseline biomarker (highest vs lowest tertile) and the MRI radiological outcome after 2 years. The mean Z-score for vascular inflammation (VI) combined soluble intercellular cell adhesion molecule-1 (sICAM-1), soluble platelet selectin (sP-selectin), CD40 ligand (sCD40 L), platelet factor-4 (PF-4) and homocysteine; Z-score for systemic inflammation (SI) combined high-sensitivity C-reactive protein (hsCRP), interleukin-1α and -6 (IL-1α and IL-6, respectively) and tumor necrosis factor-α (TNF-α). RESULTS: The study group comprised 123 patients (age, mean±SD: 72.2±8 years, 49% females), with lacunar stroke (n=49), vascular dementia (n=48), and vascular parkinsonism (n=26). Moreover, 34.9% patients experienced radiological progression, 43% had progression of isolated white matter lesions (WMLs), 23.2% had new lacunes, and 34.8% had both WMLs progression and new lacunes. After adjustment for confounders (age, sex, blood pressure, MRI lesions load), the PF-4 (OR; 95% CI 5.5; 1.5-21), sCD40L (4.6; 1.1-18.6), IL-6 (7.4; 1.48-37), Z-score for VI (4.5; 1.1-18.6), and, marginally, homocysteine (4.1; 0.99-17) were associated with the risk of any radiological progression; further, homocysteine (2.4; 1.4-14), Z-score for SI (2.1; 1.2-14) and, marginally, IL-6 (6.0; 0.95 -38) were related to the development of new lacunes; PF-4 (7.9; 1.6-38) and, marginally, the Z-score for VI (4.2; 0.9-19.5) were correlated with the risk of WMLs progression. Additional adjustment for clinical SVD manifestations did not significantly alter the results. CONCLUSION: The data supports the concept that ED modulates the radiological progression of SVD and WMLs and lacunes are associated with different inflammatory markers.

Reduced Lung Function and Cerebral Small Vessel Disease in Japanese Men: the Shiga Epidemiological Study of Subclinical Atherosclerosis (SESSA).

AIM: We aimed to investigate the association between reduced lung function and cerebral small vessel diseases via cranial magnetic resonance imaging (MRI) in the cross-sectional study of the general Japanese population. METHODS: We recruited participants aged ≥40 years from the general population of a single city in Japan. We clarified the comorbidities and treatments, smoking habits, second-hand smoke exposure, current alcohol consumption, education level, exercise habits, and occupation. The pulmonary function test was performed to assess the forced expiratory volume in 1 second (FEV1) % predicted and forced vital capacity (FVC) % predicted values. Cranial MRI was performed to evaluate the white matter lesions (WMLs) and lacunar infarcts. We examined the association of the WMLs and lacunar infarcts with a 1-standard deviation (SD) lower in the FEV1 % predicted and FVC % predicted, on the basis of the smoking status. RESULTS: A total of 473 men were examined. The association of WMLs and lacunar infarcts with the spirometry-based indices were significant only in never smokers. The association between lung function impairment and cerebral small vessel disease did not change after further adjusting for second-hand smoke exposure. CONCLUSION: In a community-based sample of Japanese men, we found an association between reduced lung function and WMLs and lacunar infarcts in never smokers.

Endothelium and Oxidative Stress: The Pandora's Box of Cerebral (and Non-Only) Small Vessel Disease?

Common cerebral small vessel disease (cSVD) abnormalities are a common neuroradiological finding, especially in the elderly. They are associated with a wide clinical spectrum that leads to an increasing disability, impaired global function outcome and a reduced quality of life. A strong association is demonstrated with age and hypertension and other common vascular risk factors, including diabetes mellitus, dyslipoproteinemia, smoking, low vitamin B12 level, and hyperomocysteinemia. Although these epidemiological associations suggest a systemic involvement, etiopathogenetic mechanisms remain unclear. This review focuses on the potential role of endothelial dysfunction and oxidative stress in the pathogenic cascade leading to cSVD. We stressed on the central role of those pathways, and suggest the importance of quantifying the cerebral (and non-only) "endotheliopathic and oxidative load" and its clinical presentation that could lead to a better determination of vascular risk degree. In addition, understanding underlying pathogenic mechanisms could allow us to slow down the progression of vascular damage and, therefore, prevent the disability due to reiterated microvascular damage.

Visceral obesity is associated with white matter hyperintensity and lacunar infarct.

BACKGROUND: The presence of white matter hyperintensity (WMH) and lacunar infarct are recognized as risk factors of dementia, stroke and mortality. It is undetermined whether visceral adipose tissue (VAT) area is associated with an increased risk of cerebral small vessel disease. We explored whether VAT area was responsible for cerebral small vessel disease through the identification of WMH and lacunar infarct. SUBJECTS: A total of 2046 subjects free of cerebrovascular disease who underwent brain magnetic resonance imaging and abdominal fat computed tomography during a general health check-up were enrolled. RESULTS: The prevalence of cerebral WMH was 37.7%. Subjects with WMH had greater VAT area and higher BMI and waist circumference than those without WMH, although significant differences in subcutaneous adipose tissue (SAT) area were not shown. Subjects with lacunar infarct also had significantly greater VAT area and higher waist circumference and BMI than those without lacunar infarct. Multivariate analyses adjusted for age, sex, diabetes, hypertension, smoking and alcohol, showed VAT area was an independent risk factor of cerebral WMH (odds ratio (OR): 1.13, 95% confidence interval (CI): 1.02-1.24, P=0.016), whereas waist circumference and SAT area were not significantly associated with the risk of WMH. Likewise, VAT area was also independently associated with lacunar infarct (OR: 1.38, 95% CI: 1.06-1.81, P=0.018), whereas the other anthropometric measures were not related with lacunar infarct. CONCLUSIONS: VAT has a significant association with cerebral small vessel disease, which was defined as WMH or lacunar infarct. Visceral obesity can be a potential therapeutic target for the prevention of cerebral small vessel disease.

Adult primary angiitis of the central nervous system: isolated small-vessel vasculitis represents distinct disease pattern.

Objectives: We aimed to identify whether presentations and outcomes in adult patients with isolated small-vessel primary angiitis of the CNS (PACNS) would differ from other patients with large/medium-vessel involvement. Methods: In the French PACNS cohort, we compared the characteristics, treatments and outcomes of patients with isolated small-vessel disease (normal CT, MR and/or conventional angiograms, brain biopsy positive for vasculitis) with other patients who had large/medium-vessel involvement (vessel abnormalities on CT, MR or conventional angiograms). A good functional outcome was defined as a modified Rankin scale ⩽2 at last follow-up, regardless of the occurrence of relapse. Results: Among the 102 patients in the cohort, 26 (25%) had isolated small-vessel PACNS, whereas the 76 others demonstrated large/medium-vessel involvement. Patients with isolated small-vessel PACNS had more seizures (P < 0.0001), cognitive (P = 0.02) or consciousness impairment (P = 0.03) and more dyskinesias (P = 0.002) but less focal deficits (P = 0.0002) than other PACNS patients. They also had more abnormal cerebrospinal fluid analysis (P = 0.008) and gadolinium enhancements on MRI (P = 0.001) but less frequent acute ischaemic lesions (P < 0.0001) than patients with large/medium-vessel involvement. Treatments and modified Rankin scale at last follow-up did not differ between groups. Thirty-two (31%) patients relapsed; 14 (54%) with isolated small-vessel PACNS vs 18 (24%) with large/medium-vessel involvement (P = 0.004). Eight patients died, with no difference between the groups (P = 0.97). Conclusion: In our cohort, adult patients with isolated small-vessel PACNS presented some distinct disease features and relapsed more often than other PACNS patients who had large/medium-vessel involvement. Functional outcomes and mortality did not differ.

Synergistic effects of longitudinal amyloid and vascular changes on lobar microbleeds.

OBJECTIVE: To determine whether amyloid and hypertensive cerebral small vessel disease (hCSVD) changes synergistically affect the progression of lobar microbleeds in patients with subcortical vascular mild cognitive impairment (svMCI). METHODS: Among 72 patients with svMCI who underwent brain MRI and [11C] Pittsburgh compound B (PiB)-PET, 52 (72.2%) completed the third year of follow-up. These patients were evaluated by annual neuropsychological testing, brain MRI, and follow-up PiB-PET. RESULTS: Over 3 years, 31 of 52 patients (59.6%) had incident cerebral microbleeds (CMBs) in the lobar and deep regions. Both baseline and longitudinal changes in lacune numbers were associated with increased numbers of lobar and deep microbleeds, while baseline and longitudinal changes in PiB uptake ratio were associated only with the progression of lobar microbleeds, especially in the temporal, parietal, and occipital areas. Regional white matter hyperintensity severity was also associated with regional lobar CMBs in the parietal and occipital regions. There were interactive effects between baseline and longitudinal lacune number and PiB retention on lobar microbleed progression. Increased lobar, but not deep, CMBs were associated with decreased scores in the digit span backward task and Rey-Osterrieth Complex Figure Test. CONCLUSIONS: Our findings suggest that amyloid-related pathology and hCSVD have synergistic effects on the progression of lobar microbleeds, providing new clinical insight into the interaction between amyloid burden and hCSVD on CMB progression and cognitive decline with implications for developing effective prevention strategies.

Accelerated development of cerebral small vessel disease in young stroke patients.

OBJECTIVE: To study the long-term prevalence of small vessel disease after young stroke and to compare this to healthy controls. METHODS: This prospective cohort study comprises 337 patients with an ischemic stroke or TIA, aged 18-50 years, without a history of TIA or stroke. In addition, 90 age- and sex-matched controls were included. At follow-up, lacunes, microbleeds, and white matter hyperintensity (WMH) volume were assessed using MRI. To investigate the relation between risk factors and small vessel disease, logistic and linear regression were used. RESULTS: After mean follow-up of 9.9 (SD 8.1) years, 337 patients were included (227 with an ischemic stroke and 110 with a TIA). Mean age of patients was 49.8 years (SD 10.3) and 45.4% were men; for controls, mean age was 49.4 years (SD 11.9) and 45.6% were men. Compared with controls, patients more often had at least 1 lacune (24.0% vs 4.5%, p < 0.0001). In addition, they had a higher WMH volume (median 1.5 mL [interquartile range (IQR) 0.5-3.7] vs 0.4 mL [IQR 0.0-1.0], p < 0.001). Compared with controls, patients had the same volume WMHs on average 10-20 years earlier. In the patient group, age at stroke (ß = 0.03, 95% confidence interval [CI] 0.02-0.04) hypertension (ß = 0.22, 95% CI 0.04-0.39), and smoking (ß = 0.18, 95% CI 0.01-0.34) at baseline were associated with WMH volume. CONCLUSIONS: Patients with a young stroke have a higher burden of small vessel disease than controls adjusted for confounders. Cerebral aging seems accelerated by 10-20 years in these patients, which may suggest an increased vulnerability to vascular risk factors.

Endothelial Function, Inflammation, Thrombosis, and Basal Ganglia Perivascular Spaces in Patients with Stroke.

BACKGROUND AND OBJECTIVE: Recent studies suggest perivascular spaces are a marker of small vessel disease, blood-brain barrier permeability, and inflammation, but little is known about their risk factors and associations with peripheral blood markers. MATERIALS AND METHODS: In prospectively recruited patients with recent minor ischemic stroke, we investigated the influence of age, sex, hypertension, diabetes, and smoking on the severity of perivascular spaces in the basal ganglia seen on T2-weighted magnetic resonance imaging. We assessed plasma markers of endothelial function (von Willebrand factor, intracellular adhesion molecule-1), inflammation (interleukin-6, tumor necrosis factor-alpha, C-reactive protein), and thrombosis (fibrinogen, prothrombin fragments 1 + 2, thrombin-antithrombin complex, tissue plasminogen activator, D-dimer). We used a validated semi-automated method to measure basal ganglia perivascular spaces count and volume. We tested uni- and multivariable associations between blood markers and basal ganglia perivascular spaces count and volume. FINDINGS: In 100 patients (median age: 67 years, range: 37-92), on adjusted analysis, basal ganglia perivascular spaces count was associated with age (r = .117, P = .003) and hypertension (r = 2.225, P = .013). On multivariable linear regression, adjusted for age, sex, hypertension, smoking and diabetes, reduced von Willebrand factor was associated with increased basal ganglia perivascular spaces count (r = -.025, P = .032). CONCLUSION: The association of increased basal ganglia perivascular spaces count with reduced von Willebrand factor is novel. As von Willebrand factor may promote cerebral endothelial integrity, insufficient von Willebrand factor is consistent with dysfunctional cerebral endothelium and increased basal ganglia perivascular spaces in cerebral small vessel disease. Quantitative perivascular spaces measurement may increase sensitivity to detect cerebral endothelial dysfunction.

Brain Microvasculature Involvement in ANCA Positive Vasculitis.

OBJECTIVE: Endothelial dysfunction is associated with arterial stiffness, a factor that is increasingly recognised as an important determinant of cardiovascular risk. High-flow organs such as the brain and kidneys are particularly sensitive to excessive pressure and flow pulsatility. High, local blood flow is associated with low microvascular impedance, which facilitates the penetration of excessive pulsatile energy into the microvascular bed leading to tissue damage. Systemic endothelial dysfunction and arterial stiffness have been demonstrated in peripheral vessels in associated vasculitis (AAV). Although, the brain involvement is not infrequent in AAV, it has not been evaluated previously. Our aim is to evaluate the involvement of the brain microvasculature in AAV. METHODS: Twenty-three patients with inactive AAV were studied. Brain blood flow was assessed by transcranial Doppler (TCD) and single-photon positron emission tomography (SPECT), structural brain involvement by brain MRI and cognitive scores by Montreal Cognitive Assessment (MoCA) test. RESULTS: Lower mean flow velocity (MFV) was associated to altered SPECT perfusion, higher white matter changes (WMC), lower MoCA scores and younger age (p < 0.05). Middle cerebral artery pulsatility index (MCA-PI) was related to hypertension, diabetes, lower scores on MoCA, increased vasculitis damage index (VDI) and perfusion impairment in SPECT (p < 0.05). These data were reproduced for all intracranial arteries. Up to 88.9% of patients had WMC on MRI. A higher lesion load was associated with age, decreased MoCA and fewer MFV with higher PI. The multivariable linear regression analysis showed that the greater the lesion loads, greater the bifrontal atrophy, MCA-PI and lower MoCA scores. Up to 60.9% of patients presented a decreased MoCA score (p = 0.012). It appeared to be related to VDI (p = 0.04), WMC (p = 0.004) and altered SPECT (p = 0.05). CONCLUSIONS: The alterations in brain perfusion SPECT, the presence of white matter lesions on MRI, as well as increased PI and RI with lower MFV of the cerebral vessels in TCD suggest the presence of microangiopathy in asymptomatic AAV that could lead to cognitive impairment.