Prevalence of and risk factors for cerebral microbleeds in a general Japanese elderly community

Pro-Hemorrhagic Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy Associated with NOTCH3 p.R75P Mutation with Low Vascular NOTCH3 Aggregation Property

OBJECTIVES

Intracerebral hemorrhage (ICH) and cerebral microbleeds (CMB) in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy are more common in East Asian populations than in people of white European ancestry. We hypothesized that the ethnic difference is explained by the East Asian-specific NOTCH3 p.R75P mutation.

METHODS

This retrospective observational study included 118 patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy in Japanese and Korean cohorts. We investigated whether the p.R75P mutation is associated with symptomatic ICH and multiple CMB (>5) using quasi-Poisson regression models. We predicted the NOTCH3 extracellular domain protein structures in silico and graded NOTCH3 extracellular domain immunostaining in skin vessels of some patients, with subsequent comparisons between p.R75P and other conventional mutations.

RESULTS

Among 63 Japanese patients (median age 55 years; 56% men), 15 had a p.R75P mutation, significantly associated with symptomatic ICH (adjusted relative risk 9.56, 95% CI 2.45-37.31), multiple CMB (3.00, 1.34-6.71), and absence of temporopolar lesions (4.91, 2.29-10.52) after adjustment for age, sex, hypertension, and antithrombotics. In the Korean cohort (n = 55; median age 55 years; 51% men), the p.R75P mutation (n = 13) was also associated with symptomatic ICH (8.11, 1.83-35.89), multiple CMB (1.90, 1.01-3.56), and absence of temporopolar lesions (2.32, 1.08-4.97). Structural analysis revealed solvent-exposed free cysteine thiols in conventional mutations, directly causing aggregation, whereas a stereochemically incompatible proline residue structure in p.R75P lowers correct disulfide bond formation probability, indirectly causing aggregation. Pathologically, the p.R75P mutation resulted in less vascular NOTCH3 extracellular domain accumulation than the other conventional mutations.

INTERPRETATION

NOTCH3 p.R75P mutation is associated with hemorrhagic presentations, milder temporopolar lesions, and distinct mutant protein structure properties. ANN NEUROL 2024;95:1040-1054.

Prevalence and Risk Factors of Cerebral Microbleeds in Community-Dwelling Adults in Urban Delhi

BACKGROUND

Several observational studies have reported the prevalence of cerebral microbleeds (CMBs) and their risk factors in an elderly population. Any information in this regard is currently lacking from India. Aim of this study was to estimate the prevalence, risk factors of CMBs, and association with cognition in an Indian urban population aged 50 years and above.

METHODS

Household surveys were conducted as part of ongoing Longitudinal Cognition and Aging Research on Population of the National Capital Region (LoCARPoN) study in areas of urban Delhi. Magnetic resonance imaging of the brain was performed in 2599 participants. Using standard neuropsychological battery, mean Z-scores for each domain (memory, executive, information) were derived. Binary and stepwise logistic regression models were used to determine associated risk factors for the presence of CMB and its association with cognitive domains.

RESULTS

The prevalence of CMBs was 14.42% (95% confidence interval [CI]: 13.06-15.73). Of these, 203 (7.81%) participants had single CMBs and 172 (6.61%) had multiple microbleeds (≥2). Higher prevalence was observed in older age (60-70 years: odds ratio [OR]: 1.25 [95% CI: 0.93-1.67]; 70-80 years: OR: 2.05 [95% CI: 1.48-2.84]; ≥80 years: OR: 3.27 [95% CI: 1.97-5.44]) compared to individuals in the age group 50-60 years. History of stroke (OR: 2.97 [95% CI: 1.56-5.66]), hypertension (OR: 1.36 [95% CI: 1.05-1.75]), and smoking (OR: 1.43 [95% CI: 1.11-1.85]) was associated with at least one CMB. Multiple CMBs were associated with worse scores in memory and executive domains.

CONCLUSION

Older age, hypertension, history of stroke, and history of smoking emerged as important risk factors for the presence of multiple CMBs. Follow-up study is required to determine implications of CMBs.

Neuropathologic correlates of cerebral microbleeds in community-based older adults

Cerebral microbleeds (CMBs) appearing as hypointense foci on T2*-weighted magnetic resonance images are small hemorrhages that have been linked to cognitive decline and increased mortality. However, the neuropathologic correlates of CMBs in community-based older adults are poorly understood. The present study investigated the association of age-related neuropathologies with CMBs in community-based older adults. Cerebral hemispheres from 289 participants of the Rush Memory and Aging Project, Religious Orders Study, Minority Aging Research Study, and Rush Alzheimer's Disease Clinical Core underwent ex vivo MRI and detailed neuropathologic examination. Following Bonferroni correction, CMBs in the cerebrum overall and in the frontal lobe were associated with cerebral amyloid angiopathy, CMBs in the frontal lobe were also associated with arteriolosclerosis, and CMBs in the basal ganglia showed a borderline significant association with microinfarcts. These findings suggest that CMBs can aid in the prediction of small vessel disease in community-based older adults. Finally, CMBs were not associated with dementia, suggesting that CMBs in community-based older adults may not be linked to substantial cognitive impairment.

Meta-Analysis of the Relationship between the Prognosis of Acute Cerebral Infarction Intravenous Lysis and Cerebral Microbleeds Based on Intelligent Medical Care

The accelerated pace of life leads to people's unhealthy living habits such as irregular diet, irregular work and rest, and fatigued work. The incidence of acute cerebral infarction (ACI) is increasing year by year. Intravenous thrombolysis is the best solution for clinical treatment of ACI, but intravenous thrombolysis increases the risk of cerebral microbleeds and even seriously damages the brain of patients. It is crucial to analyze the relationship between intravenous thrombolysis of ACI and cerebral microbleeds. Using intelligent medical methods such as BP neural network (BPNN), meta-analysis was carried out on the prognosis of ACI intravenous thrombolysis and cerebral microbleeds, and the basic data indicators, living habits indicators, and ACI intravenous thrombolysis indicators of ACI patients were analyzed. The experimental results showed that the odds ratios (OR) of systolic blood pressure before ACI intravenous thrombolysis, blood glucose concentration after ACI intravenous thrombolysis, diastolic blood pressure before ACI intravenous thrombolysis, and diastolic blood pressure after ACI intravenous thrombolysis on cerebral microbleeds after ACI intravenous thrombolysis were 0.97, 0.44, 0.13, and 0.07, respectively. Long-term intravenous thrombolysis with ACI, high systolic blood pressure after NIHSS thrombolysis with high scores, and blood glucose concentration before thrombolysis had OR >1, which were risk factors for cerebral microbleeds after intravenous thrombolysis with ACI. Therefore, paying attention to the risk factors of cerebral microbleeds during ACI intravenous thrombolysis can effectively reduce cerebral microbleeds after ACI intravenous thrombolysis and improve the treatment efficiency of ACI patients.

Association between antiplatelet medication and cerebral microbleeds in stroke-free population

BACKGROUND

Cerebral microbleeds (CMBs) may increase the risk of future intracerebral hemorrhage and ischemic stroke. However, It is unclear whether antiplatelet medication is associated with CMBs. This study aimed to investigate the association between antiplatelet medication and CMBs in a community-based stroke-free population.

METHODS

In this cross-sectional study, stroke-free participants aged 18-85 years were recruited from a community in Beijing, China. Demographic, clinical, and antiplatelet medication data were collected through a questionnaire, and all participants underwent blood tests and brain magnetic resonance imaging at 3.0T. The presence, count, and location of CMBs were evaluated using susceptibility-weighted imaging. The association between antiplatelet medication and the presence of CMBs was analyzed using multivariable logistic regression. The associations between antiplatelet medication and CMBs by location (lobar, deep brain or infratentorial, and mixed regions) were also analyzed using multinomial logistic regression. A linear regression analysis was conducted to determine the association between antiplatelet medication and the log-transformed number of CMBs.

RESULTS

Of the 544 participants (mean age: 58.65 ± 13.66 years, 217 males), 119 participants (21.88%) had CMBs, and 64 participants (11.76%) used antiplatelet medication. Antiplatelet medication was found to be associated with CMBs at any location [odds ratio (OR) = 2.39, 95% CI: 1.24-4.58] and lobar region (OR = 2.83, 95% CI: 1.36-5.86), but not with the number of CMBs (β = 0.14, 95% CI: -0.21-0.48). Among antiplatelet medications, aspirin use was found to be associated with any CMB (OR = 3.17, 95% CI: 1.49-6.72) and lobar CMBs (OR = 3.61, 95% CI: 1.57-8.26).

CONCLUSIONS

Antiplatelet medication was associated with CMBs in stroke-free participants, particularly lobar CMBs. Among antiplatelet medications, aspirin use was associated with any CMB and lobar CMBs. Our findings suggest that it might be essential to optimize the management of antiplatelet medication in the stroke-free population with a higher burden of vascular risk factors to reduce the potential risk of CMBs.

Association Between Diabetes and Gray Matter Atrophy Patterns in a General Older Japanese Population: The Hisayama Study

OBJECTIVE

To examine the association between diabetes and gray matter atrophy patterns in a general older Japanese population.

RESEARCH DESIGN AND METHODS

In 2012, a total of 1,189 community-dwelling Japanese aged ≥65 years underwent brain MRI scans. Regional gray matter volumes (GMV) and intracranial volume (ICV) were measured by applying voxel-based morphometry (VBM) methods. The associations of diabetes and related parameters with the regional GMV/ICV were examined using an ANCOVA. The regional gray matter atrophy patterns in the subjects with diabetes or elevated fasting plasma glucose (FPG) or 2-h postload glucose (2hPG) levels were investigated using VBM.

RESULTS

Subjects with diabetes had significantly lower mean values of GMV/ICV in the frontal lobe, temporal lobe, insula, deep gray matter structures, and cerebellum than subjects without diabetes after adjusting for potential confounders. A longer duration of diabetes was also significantly associated with lower mean values of GMV/ICV in these brain regions. The multivariable-adjusted mean values of the temporal, insular, and deep GMV/ICV decreased significantly with elevating 2hPG levels, whereas higher FPG levels were not significantly associated with GMV/ICV of any brain regions. In the VBM analysis, diabetes was associated with gray matter atrophy in the bilateral superior temporal gyri, right middle temporal gyrus, left inferior temporal gyrus, right middle frontal gyrus, bilateral thalami, right caudate, and right cerebellum.

CONCLUSIONS

The current study suggests that a longer duration of diabetes and elevated 2hPG levels are significant risk factors for gray matter atrophy in various brain regions.

The Prevalence and Risk Factors of Cerebral Microbleeds: A Community-Based Study in China

Introduction

Cerebral microbleeds (CMBs) are frequently found in the healthy elderly. However, data on the prevalence and risk factors of CMBs in the general population of China are lacking.

Methods

A cross-sectional study focusing on the prevalence and risk factors of CMBs was conducted in stroke-free elderly from Shanghai Wuliqiao community. MRI was performed at 3Tesla and cardiovascular risk factors (eg, age, smoking history, and hypertension), cerebral small vessel disease (CSVD) markers (eg, white matter hyperintensities, lacunar infarction, and enlarged perivascular space) and genetic information (eg, APOE, CR1) were recorded. Poisson regression was used to analyze the risk factors of the presence and location of microbleeds.

Results

A total of 199 participants (70.8±7.2 years old; male 31.2%) were finally included in our analysis. The overall prevalence of CMBs was 12.6% (25/199) and increased with age from 7.5% (55-64 years old) to 19.3% (over 75 years old). Of those with CMBs, most of them (16/25) located in the deep/mixed region and had 1-2 CMBs (18/25). Poisson regression analysis showed that white matter hyperintensities (OR=1.22, 95% CI: 1.16-1.29), APOE ε4+ carrier (OR=2.16, 95% CI: 1.18-3.96) and CR1 non-F/F isoform (OR=7.78, 95% CI: 4.34-13.96) were associated with CMBs. Further analysis found that in addition to the above three risk factors, hypertension (OR=2.98, 95% CI: 1.16-7.64), lacunar infarction (OR=2.39, 95% CI: 1.19-4.81) also increased the risk of deep/mixed CMBs.

Conclusion

The prevalence of cerebral microbleeds is similar to other countries. Cardiovascular risk factors, CSVD markers, and genetic factors (APOE ε4, CR1 non-F/F isoform) were associated with CMBs, suggesting an interaction of multiple pathogenesis in Chinese stroke-free community population.

Relationship of Four Blood Pressure Indexes to Subclinical Cerebrovascular Diseases Assessed by Brain MRI in General Japanese Men

Aim: The relationship of blood pressure (BP) indexes (systolic blood pressure [SBP], diastolic blood pressure [DBP], pulse pressure [PP], mean arterial pressure [MAP]) to subclinical cerebrovascular diseases (SCVDs) remains unclear. This study aimed to elucidate the relationship of four BP indexes measured at two visits on SCVDs assessed by magnetic resonance imaging (MRI) in general Japanese men.

Methods: In general Japanese men aged 40–79 years ( N =616), office BP indexes were measured at two visits (Visits 1 [2006–2008] and 2 [2010–2014]). MRI images obtained on the third visit (2012–2015) were examined for prevalent SCVDs: lacunar infarction, periventricular hyperintensity (PVH), deep subcortical white matter hyperintensity (DSWMH), microbleeds, and intracranial artery stenosis (ICAS). Using a multivariable logistic regression analysis, we computed and estimated the odds ratio of each prevalent SCVD for one standard deviation higher BP indexes. The same analyses were performed using home BP.

Results: All four office BP indexes at both visits associated with lacunar infarction. Visit 1 and 2 DBP and Visit 1 MAP associated with PVH and DSWMH, and Visit 1 SBP associated with DSWMH. All Visit 2 BP indexes appear to show stronger association with microbleeds than Visit 1 indexes, and Visit 1 and 2 SBP, PP, and MAP showed similar associations with ICAS. Additional analyses using home BP indexes revealed similar relationships; however, the significance of some relationships decreased.

Conclusion: In general Japanese men, BP indexes were associated with most of SCVDs, and BP indexes measured at different periods associated with different SCVDs assessed by MRI.

Associations Between Plasma Ceramides and Cerebral Microbleeds or Lacunes

OBJECTIVE

High plasma ceramide levels and ratios are associated with poor outcomes in individuals with cardiovascular disease; less is known about their relation to cerebral small vessel disease. We examined whether high plasma ceramide levels or ratios were associated with cerebral microbleeds (CMBs) and lacunes and whether associations differ by sex. Approach and Results: We included 548 participants enrolled in the MCSA (Mayo Clinic Study of Aging) with concurrent plasma ceramide assays and magnetic resonance imaging. CMBs were quantified on T2* magnetic resonance imaging and lacunes on T2 fluid-attenuated inversion recovery magnetic resonance imaging. Fasting plasma ceramides were assayed using liquid chromatography-electrospray ionization tandem mass spectrometry. We used logistic regression models adjusting for age, sex, hypertension, and diabetes mellitus to examine the relationship between ceramides and presence of a lacune; hurdle models were used for presence and number of CMBs. Each SD increase in the log ceramide C16:0/24:0 ratio was associated with greater odds of a CMB (odds ratio, 1.28 [95% CI, 1.01-1.64]). There was an interaction between sex and the ceramide C16:0/24:0 ratio (P=0.049). The association between this ratio and presence of a CMB was stronger for women (odds ratio, 1.87 [95% CI, 1.20-3.00]) than men (odds ratio, 1.09 [95% CI, 0.80-1.46]). Several ceramides and all ceramide ratios were associated with number of CMBs. We did not find associations between plasma ceramides and lacunes.

CONCLUSIONS

In a population-based sample, the plasma ceramide C16:0/24:0 ratio was associated with CMBs and was stronger for women. Plasma ceramides are differentially associated with cerebral small vessel pathologies.

Advance of antithrombotic treatment in patients with cerebral microbleed

With the elder proportion increasing and the antithrombotic agents widely using as well as the newly magnetic resonance imaging sequence emerging, the detection rate of cerebral microbleed (CMB) is gradually raising in recent years. As we all know that CMB mainly reflects the severity of deeply small vessel lesions, which predicts hemorrhagic transformation. Whereby, to some patients with both CMB and remarkable antithrombotic indication, treatment becomes a dilemma. We have to face the challenge of weighing the pros and cons of both drug indication and bleeding risk when making a proper decision for patients. This study summarized recent advance on CMB diagnosis and treatment, to provide a useful reference to physicians in their clinical practice.

The relation between APOE genotype and cerebral microbleeds in cognitively unimpaired middle- and old-aged individuals

Positive associations between cerebral microbleeds (CMBs) and APOE-ε4 (apolipoprotein E) genotype have been reported in Alzheimer's disease, but show conflicting results. We investigated the effect of APOE genotype on CMBs in a cohort of cognitively unimpaired middle- and old-aged individuals enriched for APOE-ε4 genotype. Participants from ALFA (Alzheimer and Families) cohort were included and their magnetic resonance scans assessed (n = 564, 50% APOE-ε4 carriers). Quantitative magnetic resonance analyses included visual ratings, atrophy measures, and white matter hyperintensity (WMH) segmentations. The prevalence of CMBs was 17%, increased with age (p < 0.05), and followed an increasing trend paralleling APOE-ε4 dose. The number of CMBs was significantly higher in APOE-ε4 homozygotes compared to heterozygotes and non-carriers (p < 0.05). This association was driven by lobar CMBs (p < 0.05). CMBs co-localized with WMH (p < 0.05). No associations between CMBs and APOE-ε2, gray matter volumes, and cognitive performance were found. Our results suggest that cerebral vessels of APOE-ε4 homozygous are more fragile, especially in lobar locations. Co-occurrence of CMBs and WMH suggests that such changes localize in areas with increased vascular vulnerability.

[Why are pericytes important for brain functions?]

Pericytes are mural cells embedded in the basal membrane surrounding endothelial cells in capillary and small vessels (from precapillary arterioles to postcapillary venules). They exist with a high coverage ratio to endothelial cells in the brain and play crucial roles in the formation and maintenance of the blood-brain barrier and the control of blood flow through a close interaction with endothelial cells. Thus, intactness of pericyte is absolutely needed for neuronal/brain functions. Ageing, life-style diseases, hypoperfusion/ischemia, drugs, and genetic factors can primarily cause pericyte dysfunctions, thereby leading to the development or progression of various brain disorders, including cerebrovascular diseases. Because pericytes also play an important role in tissue repair after brain injuries, they have received much attention as a therapeutic target even from the standpoint of functional recovery.

Association between cerebral microbleeds and hypertension in the Swedish general population "Good Aging in Skåne" study

Cerebral microbleeds (CMB) on MRI are frequent in healthy aging individuals but precede ischemic and hemorrhagic stroke and dementia. Different etiologies have been suggested for nonlobar CMB, which have a stronger connection to hypertension (HT) than do lobar CMB. This study aimed to investigate the prevalence of CMB and the association between nonlobar/lobar CMB and different blood pressure (BP) and HT treatment conditions in a longitudinal, population‐based cohort of the Good Aging in Skåne (GÅS) study. White matter hyperintensities (WMH), CMB, atrophies, and infarctions were identified with brain 3T MRI, and BP parameters were examined in 344 randomly selected subjects between 70 and 87 years old. CMB were observed in 26% of the whole cohort, increasing from 19% of subjects in their 70s to 30% of those over 80 years of age. Of these subjects, 38% had multiple CMB, and 59% had a lobar localization. CMB were associated with severe confluent WMH (odds ratio = 7.02; 2.16‐18.84). Increasing age, being male, and having HT, impaired cognition, or a history of angina pectoris were associated with CMB. Both lobar and nonlobar CMB were associated with HT. Nonlobar CMB were particularly associated with increased BP, pulse pressure, controlled HT, and uncontrolled HT. After controlling for sex and HT, age was no longer a risk factor for CMB In conclusion, sex and HT are the major risk factors for CMB, especially nonlobar CMB, which suggests stricter implementation of recommended guidelines for HT treatment in the elderly.

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.