Cerebral Microbleeds are Associated with Higher Mortality Among Ischemic Stroke Patients

Prevalence and associations of cerebral microbleeds in an Australian Memory clinic cohort

BACKGROUND

Cerebral microbleeds (CMBs) are small brain haemorrhages, identified by magnetic resonance imaging (MRI). They indicate potential for cognitive decline and mortality in memory clinic attendees. The presence of more than four CMBs is exclusionary for some clinical trials of disease-modifying therapies for Alzheimer's disease (AD). The prevalence and clinical relevance of CMBs in Australian memory clinic populations has not been reported.

AIMS

To highlight the prevalence of CMBs in an Australian memory clinic cohort and explore associations with diagnoses, topography and cognitive performance.

METHODS

We conducted a retrospective cohort study of 393 patients who attended a memory clinic (CDAMS) in Melbourne, Australia from January 2014 to December 2016 who underwent brain MRI. Data collected included age, gender, clinical diagnosis and cognitive scores. Univariable and multivariable regression analyses were performed to identify associations of CMBs with clinical and cognitive findings.

RESULTS

The prevalence of CMBs was 27% (n=107) with good inter-rater reliability (κ=0.75). CMBs were significantly associated with increasing age. Prevalence of CMBs was higher in people with mild cognitive impairment (MCI) (32%) and dementia (39%) compared with other diagnostic groups (p<0.001). Lobar-predominant CMB distribution was associated with AD diagnosis. Presence of multiple CMBs was associated with poorer cognitive performance overall.

CONCLUSIONS

CMBs are common in an Australian memory clinic population and are associated with poorer cognitive performance. "Real world" prevalence of CMBs may limit accessibility to disease-modifying therapies for many people.

Prevalence and associated factors of cerebral microbleeds in a rural population of the United States

OBJECTIVE

Cerebral microbleeds (CMBs) can carry an advanced risk for the development and burden of cerebrovascular and cognitive disorders. Large-scale population-based studies are required to identify the at-risk population.

METHOD

Ten percent (N = 3,056) of the Geisinger DiscovEHR Initiative Cohort participants who had brain magnetic resonance imaging (MRI) for any indication were randomly selected. Patients with CMBs were compared to an age-, gender-, body mass index-, and hypertension-matched cohort of patients without CMB. The prevalence of comorbidities and use of anticoagulation therapy was investigated in association with CMB presence (binary logistic regression), quantity (ordinal regression), and topography (multinomial regression).

RESULTS

Among 3,056 selected participants, 477 (15.6 %) had CMBs in their MRI. Patients with CMBs were older and were more prevalently hypertensive, with ischemic stroke, arrhythmia, dyslipidemia, coronary artery disease, and the use of warfarin. After propensity-score matching, 477 patients with CMBs and 974 without were included for further analyses. Predictors of ≥5 CMBs were ischemic stroke (OR, 1.6; 95 % CI, 1.2 -2.0), peripheral vascular disease (OR, 1.6; 95 % CI, 1.1-2.3), and thrombocytopenia (OR, 1.9; 95 % CI, 1.2-2.9). Ischemic stroke was associated with strictly lobar CMBs more strongly than deep/infra-tentorial CMBs (OR, 2.1; 95 % CI, 1.5-3.1; vs. OR, 1.4; CI, 1.1-1.8).

CONCLUSIONS

CMBs were prevalent in our white population. Old age, hypertension, anticoagulant treatment, thrombocytopenia, and a history of vascular diseases including stroke, were associated with CMBs.

Risk Factor Analysis in Patients Exhibiting Cerebral Microbleeds and the Correlation with Cognitive Impairment

Objective: To identify the risk factors contributing to cerebral microbleeds (CMBs), analyze the correlation between the quantity and distribution of CMBs and overall cognitive performance, including specific cognitive domains in patients, and investigate the underlying mechanisms by which CMBs impact cognitive function. Methods: Patients diagnosed with cerebral small vessel disease were recruited between September 2022 and September 2023. Clinical baseline data were systematically gathered. The Montreal Cognitive Assessment (MoCA) was employed to evaluate patients' cognitive status. CMBs were identified via susceptibility-weighted imaging (SWI), noting their locations and quantities. Patients were categorized into two cohorts: those without CMBs and those with CMBs. This division facilitated the comparison of basic clinical data and laboratory indicators, aiming to elucidate the risk factors associated with CMBs. Within the CMBs cohort, patients were further classified based on the number of CMBs into mild, moderate, and severe groups, and according to CMBs' locations into deep, cortical-subcortical, and mixed groups. Spearman correlation analysis and ANOVA were utilized to compare the total MoCA scores, as well as scores in specific cognitive domains, across these groups. This approach enabled the analysis of the relationship between the quantity and location of CMBs and cognitive impairment. Results: Statistically significant differences were noted between patients with and without cerebral microbleeds (CMBs) regarding gender, age, hypertension, diabetes, history of cerebral infarction, history of alcohol consumption, glycosylated hemoglobin levels, low-density lipoprotein cholesterol, and homocysteine levels (p < .05). Multifactorial logistic regression analysis identified age, hypertension, diabetes, history of alcohol consumption, and elevated homocysteine as independent risk factors for the development of CMBs. Spearman correlation analysis revealed a linear correlation between the presence of CMBs and the total score of the MoCA (r = -.837, p < .001). The group with CMBs demonstrated a significant decline in visuospatial execution function and delayed recall abilities compared to the group without CMBs (p < .05). Specifically, deep CMBs were linked to impairments in visuospatial execution function, naming, attention, computational ability, language, delayed recall, and orientation (p < .05). Cortical-subcortical CMBs affected visuospatial execution function, attention, computational ability, and delayed recall ability(p < .05). Mixed CMBs impacted visuospatial execution function and naming (p < .05). Conclusion: Age, hypertension, diabetes, history of alcohol consumption, and elevated homocysteine levels are key independent risk factors for CMBs. There exists a linear relationship between the severity of CMBs and the extent of cognitive impairment. Patients with CMBs show notable deterioration in visuospatial execution function and delayed recall abilities. Furthermore, the location of CMBs influences various specific cognitive domains.

Left ventricular hypertrophy and left atrial size are associated with ischemic strokes among non-vitamin K antagonist oral anticoagulant users

BACKGROUND

Ischemic strokes (IS) occurring in patients taking non-vitamin K antagonist oral anticoagulants (NOACs) are becoming increasingly more frequent. We aimed to determine the clinical, echocardiographic, and neuroimaging markers associated with developing IS in patients taking NOACs for atrial fibrillation.

METHODS

From a quaternary care center, clinical/radiologic data were collected from consecutive NOAC users with IS and age-matched controls without IS. Brain MRIs were reviewed for markers of cerebral small vessel disease. Variables with significant differences between groups were entered into a multivariable regression model to determine predictors of IS. Among IS patients, a Cox regression analysis was constructed to determine predictors of IS recurrence during follow-up.

RESULTS

112 patients with IS and 94 controls were included in the study. Variables significantly different between groups included apixaban use, dabigatran use, prior cerebrovascular events, hemoglobin A1c (HbA1c), left ventricular hypertrophy, left atrial volume index, and severe white matter hyperintensities. After multivariable adjustment, prior cerebrovascular events (aOR 23.86, 95% CI [6.02-94.48]), HbA1c levels (aOR 2.36, 95% CI [1.39-3.99]), left ventricular hypertrophy (aOR 2.73, 95% CI [1.11-6.71]) and left atrial volume index (aOR 1.05, 95% CI [1.01-1.08]) increased the risk of stroke, whereas apixaban use appeared to decrease the risk (aOR 0.38, 95% CI [0.16-0.92]). Malignancy was associated with IS recurrence (aHR 4.90, 95% CI [1.35-18.42]) after adjustment for age and chronic renal failure.

CONCLUSIONS

Prior cerebrovascular events, diabetes, left ventricular hypertrophy, and increased left atrial size are risk factors for developing an IS among NOAC users.

Exploring the Impact of Cerebral Microbleeds on Stroke Management

Stroke constitutes a major cause of functional disability and mortality, with increasing prevalence. Thus, the timely and accurate prognosis of stroke outcomes based on clinical or radiological markers is vital for both physicians and stroke survivors. Among radiological markers, cerebral microbleeds (CMBs) constitute markers of blood leakage from pathologically fragile small vessels. In the present review, we evaluated whether CMBs affect ischemic and hemorrhagic stroke outcomes and explored the fundamental question of whether CMBs may shift the risk-benefit balance away from reperfusion therapy or antithrombotic use in acute ischemic stroke patients. A literature review of two databases (MEDLINE and Scopus) was conducted to identify all the relevant studies published between 1 January 2012 and 9 November 2022. Only full-text articles published in the English language were included. Forty-one articles were traced and included in the present review. Our findings highlight the utility of CMB assessments, not only in the prognostication of hemorrhagic complications of reperfusion therapy, but also in forecasting hemorrhagic and ischemic stroke patients' functional outcomes, thus indicating that a biomarker-based approach may aid in the provision of counseling for patients and families, improve the selection of more appropriate medical therapies, and contribute to a more accurate choice of patients for reperfusion therapy.

Clinical and neuroimaging risk factors associated with the development of intracerebral hemorrhage while taking direct oral anticoagulants

BACKGROUND AND AIMS

Intracerebral hemorrhage (ICH) associated with direct oral anticoagulant (DOAC) usage confers significant mortality/disability. We aimed to understand the clinical and neuroimaging features associated with developing ICH among DOAC users.

METHODS

Clinical and radiological data were collected from consecutive DOAC users with ICH (DOAC-ICH) and age-matched controls without ICH from a single referral center. The frequency/distribution of MRI markers of hemorrhage risk were assessed. Baseline demographics and neuroimaging markers were compared in univariate tests. Significant associations (p < 0.1) were entered into a multivariable regression model to determine predictors of ICH.

RESULTS

86 DOAC-ICH and 94 ICH-free patients were included. Diabetes, coronary artery disease, prior ischemic stroke, smoking history, and antiplatelet usage were more common in ICH patients than ICH-free DOAC users. In the neuroimaging analyses, severe white matter hyperintensities (WMHs), lacunes, cortical superficial siderosis (cSS), and cerebral microbleeds (CMBs) were more common in the ICH cohort than the ICH-free cohort. In the multivariable regression, diabetes [OR 3.53 95% CI (1.05-11.87)], prior ischemic stroke [OR 14.80 95% CI (3.33-65.77)], smoking history [OR 3.08 95% CI (1.05-9.01)], CMBs [OR 4.07 95% CI (1.45-11.39)], and cSS [OR 39.73 95% CI (3.43-460.24)] were independently associated with ICH.

CONCLUSIONS

Risk factors including diabetes, prior stroke, and smoking history as well as MRI biomarkers including CMBs and cSS are associated with ICH in DOAC users. Although screening MRIs are not typically performed prior to initiating DOAC therapy, these data suggest that patients of high-hemorrhagic risk may be identified.

Urinary Immunoglobulin G Is Associated with Deep and Infratentorial Cerebral Microbleeds in Stroke Patients

BACKGROUND

Cerebral microbleeds (CMBs) detected on susceptibility-weighted imaging (SWI) are associated with cerebral small vessel disease. Chronic kidney disease and microalbuminuria have been associated with the presence of CMBs in stroke patients. Urinary immunoglobulin G (IgG) is measured to document glomerular injury; however, the relationship between urinary IgG and CMBs is unknown.

METHODS

We retrospectively enrolled consecutive patients who had been admitted with transient ischemic attack (TIA) or ischemic stroke and identified those who had undergone SWI and a spot urine test. The location of CMBs was classified on magnetic resonance imaging as strictly lobar, deep/infratentorial (D/I), or mixed areas. We analyzed the association between urinary IgG and the presence and location of CMBs.

RESULTS

We included 298 patients (86 female, median age 70 years, median eGFR 65.8 mL/min/1.73 m2). Positive urinary IgG and CMB results were found in 58 (19%) and 160 patients (54%), respectively. Urinary IgG positivity was significantly associated with CMBs compared with non-CMBs (28% vs. 9%, p < 0.001), and with D/I or mixed CMBs compared with non-D/I or mixed CMBs (34% vs. 10%, p < 0.001). Multivariate analysis revealed that urinary IgG and hypertension positivity were strongly associated with D/I or mixed CMBs (OR 3.479, 95% CI: 1.776-6.818, p < 0.001; OR 3.415, 95% CI: 1.863-6.258, p < 0.001).

CONCLUSIONS

Urinary IgG was associated with the prevalence of D/I or mixed location CMBs in TIA or ischemic stroke patients. Our findings provide new insights into the association between urinary IgG and the distribution of CMBs.

Association between cerebral microbleeds and inflammatory biomarkers in patients with ischemic stroke

Background

Host inflammation has been studied in patients with ischemic stroke (IS) due to large vessel occlusions. Inflammatory markers were shown to correlate with large artery atherosclerosis and worse outcomes after ischemic stroke due to large vessel occlusions. However, the association between inflammation and cerebral small vessel disease (SVD) is controversial. Mostly studied are the white matter hyperintensities; however, results regarding association of white matter hyperintensities with inflammatory markers are conflicting. We aimed to investigate the association between cerebral microbleed (CMB) load, as an indicator of SVD, and inflammation indices in patients with IS.

Results

We identified 127 patients with IS admitted within 7 days of symptom onset. CMBs were detected in 37% (n: 47) of patients. Patient’s age and Fazekas score were independently associated with CMB load. Inflammatory biomarkers were not associated with the presence or quantitative burden of CMBs.

Conclusions

White matter damage and patient’s age predicted CMB presence and number, respectively, in IS patients. However, inflammatory markers failed to show any association with such SVD signs. Prospective studies with a higher number of stroke patients are needed in order to justify our findings.

Predictive role of atrial fibrillation in cognitive decline: a systematic review and meta-analysis of 2.8 million individuals

Aims

To systematic review and meta-analyse the association and mechanistic links between atrial fibrillation (AF) and cognitive impairment.

Methods and results

PubMed, EMBASE, and Cochrane Library were searched up to 27 March 2021 and yielded 4534 citations. After exclusions, 61 were analysed; 15 and 6 studies reported on the association of AF and cognitive impairment in the general population and post-stroke cohorts, respectively. Thirty-six studies reported on the neuro-pathological changes in patients with AF; of those, 13 reported on silent cerebral infarction (SCI) and 11 reported on cerebral microbleeds (CMB). Atrial fibrillation was associated with 39% increased risk of cognitive impairment in the general population [n = 15: 2 822 974 patients; hazard ratio = 1.39; 95% confidence interval (CI) 1.25–1.53, I² = 90.3%; follow-up 3.8–25 years]. In the post-stroke cohort, AF was associated with a 2.70-fold increased risk of cognitive impairment [adjusted odds ratio (OR) 2.70; 95% CI 1.66–3.74, I² = 0.0%; follow-up 0.25–3.78 years]. Atrial fibrillation was associated with cerebral small vessel disease, such as white matter hyperintensities and CMB (n = 8: 3698 patients; OR = 1.38; 95% CI 1.11–1.73, I² = 0.0%), SCI (n = 13: 6188 patients; OR = 2.11; 95% CI 1.58–2.64, I² = 0%), and decreased cerebral perfusion and cerebral volume even in the absence of clinical stroke.

Conclusion

Atrial fibrillation is associated with increased risk of cognitive impairment. The association with cerebral small vessel disease and cerebral atrophy secondary to cardioembolism and cerebral hypoperfusion may suggest a plausible link in the absence of clinical stroke. PROSPERO CRD42018109185.

Cerebral Microbleeds Load and Long-Term Outcomes in Minor Ischemic Stroke

BACKGROUND AND PURPOSE

The association between the cerebral microbleed (CMB) count and outcomes in ischemic stroke has not been fully clarified. The aim of this study was to investigate the relationship between the CMBs count and functional outcomes in patients with a minor ischemic stroke treated with antiplatelet therapy METHODS: Non-cardiogenic minor ischemic stroke (NIHSS score < 4 on admission) patients who were treated with antiplatelet therapy were enrolled. The patients were divided into four groups based on the number of CMBs (absent, 1, 2-4, and > 4), and their clinical outcomes were compared. A poor outcome was defined as a modified Rankin scale (mRS) score of 3-6 90 days after symptom onset. Logistic regression analysis was performed to evaluate whether the CMBs count contributes to poor outcomes with well-known risk factors such as age, NIHSS score on admission, ischemic stroke recurrence, large artery atherosclerosis stroke subtype, and DWMHs.

RESULTS

A total of 240 patients were enrolled, and their pre mRS scores were matched based on CMB presence. A higher burden of CMBs was linearly correlated with the incidence of poor outcomes (4% in the absent group, 8% in the 1 CMB group, 13% in the 2-4 CMB group, and 20% in the > 4 CMB group, P = 0.002). Multivariate logistic regression analysis showed that CMBs count was one of the independent factor associated with poor outcomes (odds ratio 1.07, 95% confidence interval 1.02-1.12, P = 0.003).

CONCLUSION

The CMBs count contributes independently to poor outcomes in minor ischemic stroke patients treated with antiplatelet therapy.

In-Hospital Intravenous Thrombolysis Offers No Benefit in Mechanical Thrombectomy in Optimized Tertiary Stroke Center Setting

Purpose

Mechanical thrombectomy (MT) is the first-line treatment in acute stroke patients presenting with large vessel occlusion (LVO). The efficacy of intravenous thrombolysis (IVT) prior to MT is being contested. The objective of this study was to evaluate the efficacy of MT without IVT in patients with no contraindications to IVT presenting directly to a tertiary stroke center with acute anterior circulation LVO.

Materials and Methods

We collected the data of 106 acute stroke patients who underwent MT in a single high-volume stroke center. Patients with anterior circulation LVO eligible for IVT and directly admitted to our institution who subsequently underwent MT were included. We recorded baseline clinical, laboratory, procedural, and imaging variables and technical, imaging, and clinical outcomes. The effect of intravenous thrombolysis on 3-month clinical outcome (mRS) was analyzed with univariate tests and binary and ordinal logistic regression analysis.

Results

Fifty-eight out of the 106 patients received IVT + MT. These patients had 2.6-fold higher odds of poorer clinical outcome in mRS shift analysis (p = 0.01) compared to MT-only patients who had excellent 3-month clinical outcome (mRS 0–1) three times more often (p = 0.009). There were no significant differences between the groups in process times, mTICI, or number of hemorrhagic complications. A trend of less distal embolization and higher number of device passes was observed among the MT-only patients.

Conclusions

MT without prior IVT was associated with an improved overall three-month clinical outcome in acute anterior circulation LVO patients.

Supplementary Information

The online version of this article (10.1007/s00270-020-02727-8) contains supplementary material, which is available to authorized users.

The Impact of Cerebral Microbleeds Presence on Outcome Following Minor Stroke Treated With Antiplatelet Therapy

Background and Purpose: The relationship between cerebral microbleeds (CMBs) and prognosis in patients with ischemic stroke is still unclear. Our aim here was to verify the relationship between CMBs and functional outcomes in patients with minor ischemic stroke treated with antiplatelet therapy.

Methods: We retrospectively reviewed consecutive patients with a non-cardiogenic minor ischemic stroke (NIHSS <4 on admission) who underwent initial brain magnetic resonance imaging within the first 48 h following symptom onset. The patients were divided into two groups based on the presence or absence of CMBs and the two groups were adjusted using the pre-stroke modified Rankin scale (mRS). Poor outcome was defined as an mRS score in the 3–6 range measured 90 days after symptom onset. Logistic regression analyses were performed to determine the factors independently associated with poor outcome.

Results: A total of 240 patients (187 men, median age 66 years old) were enrolled in our study. There was a non-significant trend toward a worsening shift of 3-month mRS score distribution in the CMB group compared with the no-CMB group. Multivariate analysis revealed that the presence of CMBs was independently predictive of poor outcome (OR, 3.44; 95% CI, 1.08–10.93; P = 0.036).

Conclusion: Our findings suggest that the presence of CMBs is the predicting factor of poor outcome in minor ischemic stroke patients.