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

Cognitive impairment in cerebral small vessel disease induced by hypertension

ABSTRACT

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease, the most common cerebrovascular disease. However, the causal relationship between hypertension and cerebral small vessel disease remains unclear. Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease. Chronic hypertension and lifestyle factors are associated with risks for stroke and dementia, and cerebral small vessel disease can cause dementia and stroke. Hypertension is the main driver of cerebral small vessel disease, which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction, leukoaraiosis, white matter lesions, and intracerebral hemorrhage, ultimately resulting in cognitive decline and demonstrating that the brain is the target organ of hypertension. This review updates our understanding of the pathogenesis of hypertension-induced cerebral small vessel disease and the resulting changes in brain structure and function and declines in cognitive ability. We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

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.

Predictors of functional outcome after symptomatic intracranial hemorrhage complicating intravenous thrombolysis: results from the SITS-ISTR

BACKGROUND AND PURPOSE

Several risk factors of symptomatic intracerebral hemorrhage (SICH) following intravenous thrombolysis for acute ischaemic stroke have been established. However, potential predictors of good functional outcome post-SICH have been less studied.

METHODS

Patient data registered in the Safe Implementation of Treatment in Stroke-International Stroke Thrombolysis Register (SITS-ISTR) from 2005 to 2021 were used. Acute ischaemic stroke patients who developed post intravenous thrombolysis SICH according to the SITS Monitoring Study definition were analyzed to identify predictors of functional outcomes.

RESULTS

A total of 1679 patients with reported SICH were included, out of which only 2.8% achieved good functional outcome (modified Rankin Scale scores of 0-2), whilst 80.9% died at 3 months. Higher baseline National Institutes of Health Stroke Scale (NIHSS) score and 24-h ΔNIHSS score were independently associated with a lower likelihood of achieving both good and excellent functional outcomes at 3 months. Baseline NIHSS and hematoma location (presence of both SICHs, defined as remote and local SICH concurrently; n = 478) were predictors of early mortality within 24 h. Independent predictors of 3-month mortality were age, baseline NIHSS, 24-h ΔNIHSS, admission serum glucose values and hematoma location (both SICHs). Age, baseline NIHSS score, 24-h ΔNIHSS, hyperlipidemia, prior stroke/transient ischaemic attack, antiplatelet treatment, diastolic blood pressure at admission, glucose values on admission and SICH location (both SICHs) were associated with reduced disability at 3 months (≥1-point reduction across all modified Rankin Scale scores). Patients with remote SICH (n = 219) and local SICH (n = 964) had comparable clinical outcomes, both before and after propensity score matching.

CONCLUSIONS

Symptomatic intracerebral hemorrhage presents an alarmingly high prevalence of adverse clinical outcomes, with no difference in clinical outcomes between remote and local SICH.

Prevalence and risk factors for cerebral microbleeds in elderly Chinese patients with arteriosclerotic cardiovascular diseases: A single-center study

OBJECTIVES

People with arteriosclerotic cardiovascular diseases (ASCVD) frequently use antithrombotic agents and statins. The objective of the study was to explore the prevalence and risk factors of cerebral microbleeds (CMBs) in elderly (≥ 65 years old) Chinese people with ASCVD.

MATERIALS AND METHODS

We prospectively included 755 eligible participants with complete MRI data, and CMBs were discerned on the SWI sequence. Multivariate logistic regression was performed to analyze risk factors associated with CMBs.

RESULTS

The average age was 74.9 ± 9.5 years, and the prevalence of CMBs was 37.9% (286/755). Of those with CMBs, 65.0% (186/286) had strictly lobar CMBs, 35.0% (100/286) had deep or infratentorial CMBs with or without lobar CMBs. We divided CMBs into two groups according to their locations, lobar CMBs group (strictly lobar CMBs) and deep CMBs group (with or without lobar CMBs). Age per 10 years (odds ratio (OR) 1.42, 95% confidence interval (CI) 1.17-1.72, p < 0.001), statin use (OR 1.54, 95% CI 1.05-2.26, p = 0.03), and lacunes (OR 1.70, 95% CI 1.09-2.68, p = 0.02) were associated with any CMBs. Age per 10 years (OR 1.33, 95% CI 1.10-1.63, p < 0.001), statin use (OR 1.67, 95% CI 1.12-2.50, p = 0.01), and white matter hyperintensities (OR 1.71, 95% CI 1.17-2.51, p < 0.01) were associated with lobar CMBs. Only lacunes were associated with deep CMBs (OR 3.29, 95% CI 1.85-5.87, p < 0.001).

CONCLUSIONS

In elderly people with risk factors of ASCVD, antithrombotic drug use was not associated with any CMBs, lobar CMBs, or deep CMBs. Statin use was correlated with lobar CMBs but not deep CMBs.

The global burden of cerebral small vessel disease in low- and middle-income countries: A systematic review and meta-analysis

BACKGROUND

Cerebral small vessel disease (cSVD) is a major cause of stroke and dementia. Previous studies on the prevalence of cSVD are mostly based on single geographically defined cohorts in high-income countries. Studies investigating the prevalence of cSVD in low- and middle-income countries (LMICs) are expanding but have not been systematically assessed.

AIM

This study aims to systematically review the prevalence of cSVD in LMICs.

RESULTS

Articles were searched from the Ovid MEDLINE and EMBASE databases from 1 January 2000 to 31 March 2022, without language restrictions. Title/abstract screening, full-text review, and data extraction were performed by two to seven independent reviewers. The prevalence of cSVD and study sample size were extracted by pre-defined world regions and health status. The Risk of Bias for Non-randomized Studies tool was used. The protocol was registered on PROSPERO (CRD42022311133). A meta-analysis of proportion was performed to assess the prevalence of different magnetic resonance imaging markers of cSVD, and a meta-regression was performed to investigate associations between cSVD prevalence and type of study, age, and male: female ratio. Of 2743 studies identified, 42 studies spanning 12 global regions were included in the systematic review. Most of the identified studies were from China (n = 23). The median prevalence of moderate-to-severe white matter hyperintensities (WMHs) was 20.5%, 40.5%, and 58.4% in the community, stroke, and dementia groups, respectively. The median prevalence of lacunes was 0.8% and 33.5% in the community and stroke groups. The median prevalence of cerebral microbleeds (CMBs) was 10.7% and 22.4% in the community and stroke groups. The median prevalence of moderate-to-severe perivascular spaces was 25.0% in the community. Meta-regression analyses showed that the weighted median age (51.4 ± 0.0 years old; range: 36.3-80.2) was a significant predictor of the prevalence of moderate-to-severe WMH and lacunes, while the type of study was a significant predictor of the prevalence of CMB. The heterogeneity of studies was high (>95%). Male participants were overrepresented.

CONCLUSIONS

This systematic review and meta-analysis provide data on cSVD prevalence in LMICs and demonstrated the high prevalence of the condition. cSVD research in LMICs is being published at an increasing rate, especially between 2010 and 2022. More data are particularly needed from Sub-Saharan Africa and Central Europe, Eastern Europe, and Central Asia.

Analysis of Risk Factors for Cerebral Microbleeds and the Relationship between Cerebral Microbleeds and Cognitive Impairment

(1) Background: Cerebral microbleeds (CMBs) are attracting increasing attention. Nevertheless, the risk factors for CMBs remain poorly identified, and the relationship between CMBs and cognitive impairment is still up for debate; (2) Objective: The present study analyzed the risk factors for CMBs and probed into the potential correlations between the presence, number, and location of CMBs and cognition; (3) Methods: This study enrolled 406 subjects who underwent both brain 3.0-T magnetic resonance imaging scans and cognitive testing. Spearman correlation was used to assess the relationship between the number of CMBs and cognition. Multiple linear regression was utilized to analyze the relationship between the regions of CMBs and each cognitive domain; (4) Results: Multivariate logistic regression analysis results showed that age (odds ratio (OR) = 1.045, 95% confidence interval (95%CI; 1.009, 1.082)), smoking (OR = 3.604, 95%CI (1.995, 6.509)), hypertension (OR = 3.607, 95%CI (2.204, 5.901)), total cholesterol (OR = 0.611, 95%CI (0.467, 0.799)), and Amyloid-β1-42 (Aβ1-42) (OR = 1.028, 95%CI (1.018, 1.037)) were the influencing factors of CMBs. Education years (OR = 0.959, 95%CI (0.930, 0.988)), white matter lesions (OR = 2.687, 95%CI (1.782, 4.051)), and CMBs (OR = 21.246, 95%CI (5.728, 21.576)) were the risk factors for cognitive impairment. Hypertension increased the probability of deep CMBs (OR = 12.54, 95%CI (2.21, 71.28)), while Aβ1-42 elevated the probability of lobar CMBs (OR = 1.02, 95%CI (1.00, 1.03)). There was a linear correlation between the number of CMBs and Montreal Cognitive Assessment scores (r = −0.756, p < 0.001). However, CMBs in each region were not related to specific cognitive domains (p > 0.05), except CMBs in the mixed group that were negatively correlated with attention (OR = −0.669, 95%CI (−0.034, −5.270)); (5) Conclusions: Taken together, serum Aβ1-42 levels are related to the presence of CMBs. Cognitive impairment is correlated with the number of CMBs rather than their region. These findings suggest that CMBs play a role in cognitive impairment and that CMBs mark the presence of diffuse vascular injury and neurodegenerative brain damage.