Location-specific risk factors for intracerebral hemorrhage: Systematic review and meta-analysis

The impact of sex on epidemiology, management, and outcome of spontaneous intracerebral hemorrhage (sICH)

OBJECTIVE

Data on sex differences in spontaneous intracerebral hemorrhages are limited.

METHODS

An automated comprehensive scoping literature review was performed using PubMed and Scopus. Articles written in English about spontaneous intracerebral hemorrhage and sex were reviewed.

RESULTS

Males experience spontaneous intracerebral hemorrhage more frequently than females, at younger ages, and have a higher prevalence of deep bleeds compared to females. Risk factors between sexes vary and may contribute to differing incidences and locations of spontaneous intracranial hemorrhage. Globally, females receive less aggressive care than males, likely impacting survival.

CONCLUSIONS

Epidemiology, risk factors, and treatment of spontaneous intracranial hemorrhage vary by sex, with limited and oftentimes conflicting data available. Further research into the sex-based differences of spontaneous intracranial hemorrhage is necessary for clinicians to better understand how to evaluate and guide treatment in the future.

Haemorrhagic stroke and brain vascular malformations in women: risk factors and clinical features

Haemorrhagic stroke is a severe condition with poor prognosis. Biological sex influences the risk factors, presentations, treatment, and patient outcomes of intracerebral haemorrhage, aneurysmal subarachnoid haemorrhage, and vascular malformations. Women are usually older at onset of intracerebral haemorrhage compared with men but have an increased risk of aneurysmal subarachnoid haemorrhage as they age. Female-specific factors such as pregnancy, eclampsia or pre-eclampsia, postmenopausal status, and hormone therapy influence a woman's long-term risk of haemorrhagic stroke. The presence of intracranial aneurysms, arteriovenous malformations, or cavernous malformations poses unique clinical dilemmas during pregnancy and delivery. In the absence of evidence-based guidelines for managing the low yet uncertain risk of haemorrhagic stroke during pregnancy and delivery in women with vascular malformations, multidisciplinary teams should carefully assess the risks and benefits of delivery methods for these patients. Health-care providers should recognise and address the challenges that women might have to confront when recovering from haemorrhagic stroke.

IL-10 protects against OPC ferroptosis by regulating lipid reactive oxygen species levels post stroke

Accumulation of reactive oxygen species (ROS), especially on lipids, induces massive cell death in neurons and oligodendrocyte progenitor cells (OPCs) and causes severe neurologic deficits post stroke. While small compounds, such as deferoxamine, lipostatin-1, and ferrostatin-1, have been shown to be effective in reducing lipid ROS, the mechanisms by which endogenously protective molecules act against lipid ROS accumulation and subsequent cell death are still unclear, especially in OPCs, which are critical for maintaining white matter integrity and improving long-term outcomes after stroke. Here, using mouse primary OPC cultures, we demonstrate that interleukin-10 (IL-10), a cytokine playing roles in reducing neuroinflammation and promoting hematoma clearance, significantly reduced hemorrhage-induced lipid ROS accumulation and subsequent ferroptosis in OPCs. Mechanistically, IL-10 activated the IL-10R/STAT3 signaling pathway and upregulated the DLK1/AMPK/ACC axis. Subsequently, IL-10 reprogrammed lipid metabolism and reduced lipid ROS accumulation. In addition, in an autologous blood injection intracerebral hemorrhagic stroke (ICH) mouse model, deficiency of the endogenous Il-10, specific knocking out Il10r or Dlk1 in OPCs, or administration of ACC inhibitor was associated with increased OPC cell death, demyelination, axonal sprouting, and the cognitive deficits during the chronic phase of ICH and vice versa. These data suggest that IL-10 protects against OPC loss and white matter injury by reducing lipid ROS, supporting further development of potential clinical applications to benefit patients with stroke and related disorders.

More severe initial manifestations and worse short-term functional outcome of intracerebral hemorrhage in the plateau than in the plain

Intracerebral hemorrhage (ICH) is one of the most devastating forms of stroke. However, studies on ICH at high altitude are insufficient. We aimed to compare the initial manifestations, imaging features and short-term functional outcomes of ICH at different altitudes, and further explore the effect of altitude on the severity and prognosis of ICH. We retrospectively recruited ICH patients from January 2018 to July 2021 from two centers at different altitudes in China. Information regarding to clinical manifestations, neuroimages, and functional outcomes at discharge were collected and analyzed. Association between altitude and initial severity, neuroimages, and short-term prognosis of ICH were also investigated. A total of 724 patients with 400 lowlanders and 324 highlanders were enrolled. Compared with patients from the plain, those at high altitude were characterized by more severe preliminary manifestations (P < 0.0001), larger hematoma volume (P < 0.001) and poorer short-term functional outcome (P < 0.0001). High altitude was independently associated with dependency at discharge (adjusted P = 0.024), in-hospital mortality (adjusted P = 0.049) and gastrointestinal hemorrhage incidence (adjusted P = 0.017). ICH patients from high altitude suffered from more serious initial manifestations and worse short-term functional outcome than lowlanders. Control of blood pressure, oxygen supplementation and inhibition of inflammation may be critical for ICH at high altitude.

Causal Association between Tea Intake and Acute Cerebrovascular Events: A Multivariate Mendelian Randomized Study in European Populations

BACKGROUND

Numerous research works have investigated the association between tea consumption and the risk of acute cerebrovascular events; however, the results are inconsistent.

OBJECTIVES

We used Mendelian randomization (MR) to evaluate the causal association between tea intake and several acute cerebrovascular events, including any ischemic stroke, large atherosclerotic stroke (LAS), cardiogenic embolic stroke (CES), small vessel stroke (SVS), intracranial hemorrhage (ICH), and subarachnoid hemorrhage (SAH).

METHODS

We obtained summary genome-wide association study (GWAS) data on tea intake and acute cerebrovascular events in populations of European ancestry. The GWAS on tea intake is derived from the UK Biobank, where we have chosen single-nucleotide polymorphisms (SNPs) closely associated with it as instrumental variables. We also obtained summary data on ischemic stroke from a GWAS meta-analysis, as well as summary data on ICH and SAH from the FinnGen study. We first explored the causal association between tea intake and several acute cerebrovascular events using univariate Mendelian randomization (UVMR), and then further assessed the causal association between tea intake and SVS using multivariate Mendelian randomization (MVMR) corrected for multiple confounders.

RESULTS

In UVMR, genetically predicted increases in tea intake were linked to a lower risk of SVS (OR: 0.58; 95% CI: 0.39, 0.86). There was no causal association between tea intake and the risk of other acute cerebrovascular events. In the MVMR, our results show that there was still a significant causal association between drinking tea and SVS, after adjusting body mass index, total cholesterol, low-density lipoprotein cholesterol, diabetes, hypertension, smoking, and alcohol consumption.

CONCLUSION

This MR study provides new genetic evidence that increased tea intake reduces the risk of SVS in the European population. However, possibly because of limited statistical power, the study did not find that tea consumption reduced the risk of several other acute cerebrovascular events.

Molecular biomarkers for vascular cognitive impairment and dementia

As disease-specific interventions for dementia are being developed, the ability to identify the underlying pathology and dementia subtypes is increasingly important. Vascular cognitive impairment and dementia (VCID) is the second most common cause of dementia after Alzheimer disease, but progress in identifying molecular biomarkers for accurate diagnosis of VCID has been relatively limited. In this Review, we examine the roles of large and small vessel disease in VCID, considering the underlying pathophysiological processes that lead to vascular brain injury, including atherosclerosis, arteriolosclerosis, ischaemic injury, haemorrhage, hypoperfusion, endothelial dysfunction, blood-brain barrier breakdown, inflammation, oxidative stress, hypoxia, and neuronal and glial degeneration. We consider the key molecules in these processes, including proteins and peptides, metabolites, lipids and circulating RNA, and consider their potential as molecular biomarkers alone and in combination. We also discuss the challenges in translating the promise of these biomarkers into clinical application.

Porous Three-Dimensional Polyurethane Scaffolds Promote Scar-Free Endogenous Regeneration After Acute Brain Hemorrhage

Intracerebral hemorrhage (ICH) is the most lethal subtype of stroke and is associated with significant morbidity and mortality. Despite advances in the clinical treatment of ICH, limited progress has been made regarding endogenous brain regeneration after ICH. Failure of brain regeneration is mainly attributed to the inhibitive regenerative microenvironment caused by secondary injury after ICH. In this study, we investigated a three-dimensional biodegradable waterborne polyurethane (BWPU) scaffold as a tool to promote brain regeneration after ICH. After implantation into the cavity following hematoma evacuation, these implanted scaffolds could act as a reservoir; store a series of necrotic debris, cytokines, and chemokines; and attract microglia/macrophages to their pores. Subsequently, these microglia/macrophages were polarized into the M1-like subtype to eliminate these substances. This process disperses M1-like immune cells and prevents the formation of dense glial scar-free structures after ICH. Inflammatory cells in scaffolds include scar-free secreted growth factors and extracellular matrix (ECM) proteins, and further induce a M2-like immune cells enriched regeneration-predominant microenvironment to promote endogenous brain regeneration with functional recovery. In summary, in this work, we have revealed the potential and mechanism of the BWPU scaffold as a tool to promote endogenous brain tissue regeneration after ICH.

Intracranial haemorrhage and falls: cause or effect?

INTRODUCTION

A difficult question in autopsy practice is whether intracranial haemorrhage has resulted from or brought about a fall.

MATERIAL AND METHODS

To address this we undertook a retrospective study of all autopsy reports (N = 2126) complied over a 10 year period (2009-2018). Of 720 patients who underwent a comprehensive post mortem neuropathologic examination we found 226 patients who had a history of a fall.

RESULTS

Of the 226 with a history of fall, 175 (79%) had an intracranial haemorrhage which was classified as truamatic (n = 134, 77%) or spontaneous (n = 41, 23%. Within the traumatic group, falls from a standing height (51%) were more common than falls involving stairs (31%) or falls from a height (12%). Cerebral contusional injury (51%) and subdural haemorrhage (45%) were the most common type of haemorrhage in the traumatic group. In the spontaneous haemorrhage group cerebral amyloid angiopathy (49%) was the commonest detected cause and was typically lobar in distribution).

CONCLUSION

We are of the view that a comprehensive analysis of fatal falls with intracranial haemorrhage warrants a detailed neuropathologic examination as part of the overall death analysis.

Long working hours and risk of hypertensive intracerebral haemorrhage among Japanese workers claiming compensation for overwork-related intracerebral haemorrhage: an unmatched case-control study

OBJECTIVES

Overwork-related cerebrovascular and cardiovascular diseases (CCVDs) constitute a major occupational and public health issue worldwide. However, to our knowledge, few studies have reported the underlying pathophysiological mechanisms. We aimed to determine whether patients with extreme workload have a greater risk of developing hypertensive intracerebral haemorrhage (ICH) located in the deep brain areas than patients without extreme workload. We also determined the association between the number of hours of overtime work and the risk of developing hypertensive ICH.

DESIGN

Unmatched case-control study.

SETTING

Database of patients claiming compensation for overwork-related CCVDs in Japan.

PARTICIPANTS

A total of 1215 patients who claimed overwork-related ICH in Japan, of whom 621 had their compensation claim approved (patients with extreme workload) and 622 did not.

PRIMARY AND SECONDARY OUTCOME MEASURES

Logistic regression analysis was performed to calculate the risk of developing hypertensive ICH in patients with extreme workload compared with those without extreme workload, adjusted for confounders such as age, occupation, smoking status, alcohol consumption and medical history. We also calculated the risk of developing hypertensive ICH in compensated patients by average monthly overtime working hours.

RESULTS

Patients with extreme workloads had a significantly higher odds ratio (OR) for developing hypertensive ICH (1.44, 95% CI: 1.10 to 1.88) than those without extreme workloads. ORs for developing hypertensive ICH according to overtime working hours showed a dose-response relationship; an overtime of 100 hours/month was associated with a significantly higher OR (1.31, 95% CI: 0.89 to 1.91; 1.41, 95% CI: 0.95 to 2.11; and 1.50, 95% CI: 1.01 to 2.22 for 60-79.9, 80-99.9 and≥100 hours/month, respectively) than that for workloads of less than 60 hours/month.

CONCLUSIONS

Regarding Japanese workers, overtime work could be associated with the risk of developing hypertensive ICH, and hypertension may play an important role in overwork-related ICH.

Essential nutrients and cerebral small vessel diseases: a two-sample Mendelian randomization study

Background

Previous studies have suggested a potential association between nutrients and cerebral small vessel disease (CSVD), but this association has not been fully addressed.

Object

We intended to clarify the causal associations between four categories of essential nutrients (amino acids, polyunsaturated fatty acids, minerals and vitamins) and two acute manifestations of CSVD (intracerebral hemorrhage and small vessel stroke) using two-sample Mendelian randomization (MR) analysis.

Method

We obtained European-based large-scale genome-wide association studies (GWASs) related to CSVD (6,255 cases and 233,058 controls) and nutrient concentrations. Causality evaluation mainly included the results of the inverse variance-weighted (IVW) method. The simple median method, the weighted median method and the MR-Egger method were adopted for sensitivity analyses.

Results

For ICH or SVS, increased levels of phenylalanine (OR = 1.188, p < 0.001) and dihomo-gamma-linolenic acid (DGLA) (OR = 1.153, p = 0.001) showed risk effects, while docosapentaenoic acid (DPA) (OR = 0.501, p < 0.001), zinc (OR = 0.919, p < 0.001), and arachidonic acid (OR = 0.966, p = 0.007) showed protective effects. For lobar hemorrhage or SVS, AA (OR = 0.978, p < 0.001), zinc (OR = 0.918, p < 0.001), and retinol (OR = 0.753, p < 0.001) showed risk effects; DPA (OR = 0.682, p = 0.022), gamma-linolenic acid (OR = 0.120, p = 0.033) and 25(OH)D (OR = 0.874, p = 0.040) showed protective effects. For nonlobar hemorrhage or SVS, DGLA (OR = 1.088, p < 0.001) and phenylalanine (OR = 1.175, p = 0.001) showed risk effects.

Conclusion

Our study analyzed the effect of nutrients on CSVD risk from a genetic perspective, with implications for CSVD prevention through nutrient supplementation.

Gender Differences in Intracerebral Hemorrhage

Differences exist between genders in intracerebral hemorrhage cause, epidemiology, and outcomes. These gender differences are in part attributable to physiologic differences; however, demographic, social/behavioral risk factors, along with health care system variation and potential family and/or clinician bias play a role as well. These factors vary from region to region and interact, making comprehensive and definitive conclusions regarding sex differences a challenging task. Differences between the genders in intracerebral hemorrhage epidemiology and extensive differences in underlying pathophysiology, intervention, risk factors, and outcome are all discussed.

Histopathology of Cerebral Microinfarcts and Microbleeds in Spontaneous Intracerebral Hemorrhage

In patients with spontaneous intracerebral hemorrhage caused by different vasculopathies, cerebral microinfarcts have the same aspect on MRI and the same applies to cerebral microbleeds. It is unclear what pathological changes underlie these cerebral microinfarcts and cerebral microbleeds. In the current study, we explored the histopathological substrate of these lesions by investigating the brain tissue of 20 patients (median age at death 77 years) who died from ICH (9 lobar, 11 non-lobar) with a combination of post-mortem 7-T MRI and histopathological analysis. We identified 132 CMIs and 204 CMBs in 15 patients on MRI, with higher numbers of CMIs in lobar ICH patients and similar numbers of CMBs. On histopathology, CMIs and CMBs were in lobar ICH more often located in the superficial than in the deep layers of the cortex, and in non-lobar ICH more often in the deeper layers. We found a tendency towards more severe CAA scores in lobar ICH patients. Other histopathological characteristics were comparable between lobar and non-lobar ICH patients. Although CMIs and CMBs were found in different segments of the cortex in lobar ICH compared to non-lobar ICH patients, otherwise similar histopathological features of cortical CMIs and CMBs distant from the ICH suggest shared pathophysiological mechanisms in lobar and non-lobar ICH caused by different vasculopathies.

Small-vessel disease in the brain

Cerebral small-vessels are generally located in the brain at branch points from major cerebral blood vessels and perfuse subcortical structures such as the white matter tracts, basal ganglia, thalamus, and pons. Cerebral small-vessel disease (CSVD) can lead to several different clinical manifestations including ischemic lacunar stroke, intracerebral hemorrhage, and vascular dementia. Risk factors for CSVD overlap with conventional vascular risk factors including hypertension, diabetes mellitus, and hypercholesterolemia, as well as genetic causes. As in cardiovascular disease, treatment of CSVD involves both primary and secondary prevention. Aspirin has not been established as a primary prevention strategy for CSVD among the general population; however, long-term antiplatelet therapy with aspirin alone continues to be the mainstay of secondary stroke prevention for non-cardioembolic ischemic stroke and high-risk TIA.

Triple Therapy Prevention of Recurrent Intracerebral Disease Events Trial: Rationale, design and progress

BACKGROUND

Patients who suffer intracerebral hemorrhage (ICH) are at very high risk of recurrent ICH and other serious cardiovascular events. A single-pill combination (SPC) of blood pressure (BP) lowering drugs offers a potentially powerful but simple strategy to optimize secondary prevention.

OBJECTIVES

The Triple Therapy Prevention of Recurrent Intracerebral Disease Events Trial (TRIDENT) aims to determine the effects of a novel SPC "Triple Pill," three generic antihypertensive drugs with demonstrated efficacy and complementary mechanisms of action at half standard dose (telmisartan 20 mg, amlodipine 2.5 mg, and indapamide 1.25 mg), with placebo for the prevention of recurrent stroke, cardiovascular events, and cognitive impairment after ICH.

DESIGN

An international, double-blind, placebo-controlled, randomized trial in adults with ICH and mild-moderate hypertension (systolic BP: 130-160 mmHg), who are not taking any Triple Pill component drug at greater than half-dose. A total of 1500 randomized patients provide 90% power to detect a hazard ratio of 0.5, over an average follow-up of 3 years, according to a total primary event rate (any stroke) of 12% in the control arm and other assumptions. Secondary outcomes include recurrent ICH, cardiovascular events, and safety.

RESULTS

Recruitment started 28 September 2017. Up to 31 October 2021, 821 patients were randomized at 54 active sites in 10 countries. Triple Pill adherence after 30 months is 86%. The required sample size should be achieved by 2024.

CONCLUSION

Low-dose Triple Pill BP lowering could improve long-term outcome from ICH.

Computed tomography in acute intracerebral hemorrhage: neuroimaging predictors of hematoma expansion and outcome

Intracerebral hemorrhage (ICH) accounts for 10–20% of all strokes worldwide and is associated with serious outcomes, including a 30-day mortality rate of up to 40%. Neuroimaging is pivotal in diagnosing ICH as early detection and determination of underlying cause, and risk for expansion/rebleeding is essential in providing the correct treatment. Non-contrast computed tomography (NCCT) is the most used modality for detection of ICH, identification of prognostic markers and measurements of hematoma volume, all of which are of major importance to predict outcome. The strongest predictors of 30-day mortality and functional outcome for ICH patients are baseline hematoma volume and hematoma expansion. Even so, exact hematoma measurement is rare in clinical routine practice, primarily due to a lack of tools available for fast, effective, and reliable volumetric tools. In this educational review, we discuss neuroimaging findings for ICH from NCCT images, and their prognostic value, as well as the use of semi-automatic and fully automated hematoma volumetric methods and assessment of hematoma expansion in prognostic studies.

Forkhead box O3 longevity genotype may attenuate the impact of hypertension on risk of intracerebral haemorrhage

OBJECTIVE

Since the G allele of forkhead box O3 ( FOXO3 ) single nucleotide polymorphism (SNP) rs2802292 is associated with resilience and longevity, ostensibly by mitigating the adverse effects of chronic cardiometabolic stress on mortality, our aim was to determine the association between the FOXO3 SNP rs2802292 genotype and risk of hypertension-mediated intracerebral haemorrhage (ICH).

METHODS

From a prospective population-based cohort of Japanese American men from the Kuakini Honolulu Heart Program (KHHP), age-adjusted prevalence of ICH by hypertension was assessed for the whole cohort after stratifying by FOXO3 genotype. Cox regression models, adjusted for age, cardiovascular risk factors and, FOXO3 and APOE genotypes, were utilized to determine relative risk of hypertension's effect on ICH. All models were created for the whole cohort and stratified by FOXO3 G -allele carriage vs. TT genotype.

RESULTS

Among 6469 men free of baseline stroke, FOXO3 G -allele carriage was seen in 3009 (46.5%) participants. Overall, 183 participants developed ICH over the 34-year follow-up period. Age-adjusted ICH incidence was 0.90 vs. 1.32 per 1000 person-years follow-up in those without and with hypertension, respectively ( P  = 0.002). After stratifying by FOXO3 genotype, this association was no longer significant in G allele carriers. In the whole cohort, hypertension was an independent predictor of ICH (relative risk [RR] = 1.70, 95% confidence interval [CI] 1.25, 2.32; P  = 0.0007). In stratified analyses, hypertension remained an independent predictor of ICH among the FOXO3 TT -genotype group (RR = 2.02, 95% CI 1.33, 3.07; P  = 0.001), but not in FOXO3 G -allele carriers (RR = 1.39, 95% CI 0.88, 2.19; P  = 0.15).

CONCLUSIONS

The longevity-associated FOXO3   G allele may attenuate the impact of hypertension on ICH risk.

Occurrence of Intracranial Hemorrhage and Associated Risk Factors in Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy: A Systematic Review and Meta-Analysis

Background and Purpose

Intracranial hemorrhage (ICH) is thought to be a rare but probably underestimated presentation of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). We conducted a systematic review and meta-analysis with the aim of comprehensively revealing the occurrence of ICH in patients with CADASIL.

Methods

English-language studies published up to September 30, 2021 were searched for in the MEDLINE (PubMed), Web of Science, and Cochrane Library databases. The design, patient characteristics, occurrence rate of ICH, and associated risk factors were retrieved for each identified relevant study.

Results

We enrolled 13 studies in the final meta-analysis, which included 1,310 patients with CADASIL. The probability of ICH occurrence in patients with CADASIL was 10.1% (95% confidence interval [CI]=5.6%–18.0%, I²=85.1%). When stratified by geographic region, the occurrence rate of ICH was much higher in Asians (17.7%; 95% CI=11.0%–28.5%, I²=76.3%) than in Europeans (2.0%; 95% CI=0.4%–10.8%, I²=82.8%). A higher burden of cerebral microbleeds (CMBs) and a history of hypertension were the most commonly recorded risk factors for ICH, which were available for three and two of the included studies, respectively.

Conclusions

Our study suggests that ICH is an important clinical manifestation of CADASIL, especially in Asians. A higher burden of CMBs and the existence of hypertension were found to be associated with a higher probability of ICH occurrence in patients with CADASIL.

Rare and Common Variants in COL4A1 in Chinese Patients With Intracerebral Hemorrhage

Here, we screened the COL4A1 variants in Chinese intracerebral hemorrhage (ICH) patients to summarize the relationship between the variants and clinical characteristics. Targeted sequencing of a 65-gene panel including COL4A1 was performed to detect all the coding regions and ±10-bp splicing sites. In total, 568 patients were included. Regarding rare nonsynonymous variants with a minor allele frequency (MAF) <0.5%, 6 missense variants and five suspicious splice site variants, absent in 573 healthy controls, were found in 11 patients. The subgroup carrying rare variants did not show specific phenotype compared with non-variant carriers. For the single nucleotide polymorphism (SNP) loci with an MAF> 5%, we did not find a significant association between the allele or genotype distribution of the SNP loci and the risk of ICH. Rs3742207 was nominally associated with death at 1-year follow-up (p = 0.02027, OR 1.857, 95% CI 1.101-3.133) after adjusted by age, hypertension history, hematoma volume and recurrent ICH history. Nevertheless, after the Bonferroni correction, the association was no longer significant. In conclusion, rare nonsynonymous variants in COL4A1 were identified in 1.94% (11/568) of Chinese ICH patients, while rs3742207 maybe indicate a worse prognosis of ICH.

Genetics and Epigenetics of Spontaneous Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a complex and heterogeneous disease, and there is no effective treatment. Spontaneous ICH represents the final manifestation of different types of cerebral small vessel disease, usually categorized as: lobar (mostly related to cerebral amyloid angiopathy) and nonlobar (hypertension-related vasculopathy) ICH. Accurate phenotyping aims to reflect these biological differences in the underlying mechanisms and has been demonstrated to be crucial to the success of genetic studies in this field. This review summarizes how current knowledge on genetics and epigenetics of this devastating stroke subtype are contributing to improve the understanding of ICH pathophysiology and their potential role in developing therapeutic strategies.

Review of Long-Term Blood Pressure Control After Intracerebral Hemorrhage: Challenges and Opportunities

Blood pressure (BP) is the most important modifiable risk factor for intracerebral hemorrhage (ICH). Elevated BP is associated with an increased risk of ICH, worse outcome after ICH, and in survivors, higher risks of recurrent ICH, ischemic stroke, myocardial infarction, and cognitive impairment/dementia. As intensive BP control probably improves the chances of recovery from acute ICH, the early use of intravenous or oral medications to achieve a systolic BP goal of <140 mm Hg within the first few hours of presentation is reasonable for being applied in most patients. In the long-term, oral antihypertensive drugs should be titrated as soon as possible to achieve a goal BP <130/80 mm Hg and again in all ICH patients regardless of age, location, or presumed mechanism of ICH. The degree of sustained BP reduction, rather than the choice of BP-lowering agent(s), is the most important factor for optimizing risk reduction, with varying combinations of thiazide-type diuretics, long-acting calcium channel blockers, ACE (angiotensin-converting enzyme) inhibitors or angiotensin receptor blockers, being the mainstay of therapy. As most patients will require multiple BP-lowering agents, and physician inertia and poor adherence are major barriers to effective BP control, single-pill combination therapy should be considered as the choice of management where available. Increased population and clinician awareness, and innovations to solving patient, provider, and social factors, have much to offer for improving BP control after ICH and more broadly across high-risk groups. It is critical that all physicians, especially those managing ICH patients, emphasize the importance of BP control in their practice.

Cerebral Hemorrhage: Pathophysiology, Treatment, and Future Directions

Intracerebral hemorrhage (ICH) is a devastating form of stroke with high morbidity and mortality. This review article focuses on the epidemiology, cause, mechanisms of injury, current treatment strategies, and future research directions of ICH. Incidence of hemorrhagic stroke has increased worldwide over the past 40 years, with shifts in the cause over time as hypertension management has improved and anticoagulant use has increased. Preclinical and clinical trials have elucidated the underlying ICH cause and mechanisms of injury from ICH including the complex interaction between edema, inflammation, iron-induced injury, and oxidative stress. Several trials have investigated optimal medical and surgical management of ICH without clear improvement in survival and functional outcomes. Ongoing research into novel approaches for ICH management provide hope for reducing the devastating effect of this disease in the future. Areas of promise in ICH therapy include prognostic biomarkers and primary prevention based on disease pathobiology, ultra-early hemostatic therapy, minimally invasive surgery, and perihematomal protection against inflammatory brain injury.

Intensive or standard blood pressure control in patients with a history of ischemic stroke: RESPECT post hoc analysis

The Recurrent Stroke Prevention Clinical Outcome (RESPECT) Study and its pooled analysis showed that intensive blood pressure (BP) lowering reduced recurrent stroke risk by 22% in patients with a history of stroke. Here, we report the effect of intensive BP lowering on the risk of recurrent stroke subtypes in patients with a history of ischemic stroke. RESPECT was a randomized clinical trial among 1280 people with a history of cerebral infarction or intracerebral hemorrhage. Participants were assigned to the intensive blood pressure control group (blood pressure < 120/80 mmHg) or standard blood pressure control group (blood pressure < 140/90 mmHg). In this post hoc analysis, we analyzed 1074 patients with a history of cerebral infarction. The mean BP at baseline was 140.7/81.4 mmHg. Throughout the follow-up period, the mean BP was 133.4/77.5 (95% CI, 132.7-134.1/76.9-78.2) mmHg in the standard group and 126.7/74.1 (95% CI, 126.0-127.4/73.5-74.8) mmHg in the intensive group. During a mean follow-up of 3.9 years, 78 first recurrent strokes occurred. Intensive treatment tended to reduce overall annual stroke recurrence (1.74% in intensive vs. 2.17% in standard; P = 0.351 by log-rank test) and did not change the risk of ischemic stroke (1.74% vs. 1.75%, P = 0.999) but markedly reduced the risk of hemorrhagic stroke (0.00% vs. 0.39%, P = 0.005). Beneficial effects of intensive BP control were observed for the risk of hemorrhagic stroke in patients with a history of ischemic stroke. The findings of this study indicate the benefit of intensive BP control for patients with a history of ischemic stroke at high risk of hemorrhagic stroke.

Milk and Fermented Milk Consumption and Risk of Stroke: Longitudinal Study

The role of milk and fermented milk consumption in stroke risk is unclear. We investigated associations of time-updated information on milk and fermented milk consumption (1997 and 2009) with total stroke, cerebral infarction, and hemorrhagic stroke risk among 79,618 Swedish women and men (mean age 61.3 years). During a mean follow-up of 17.7 years, we identified 9735 incident cases of total stroke, of which 7573 were cerebral infarctions, 1470 hemorrhagic strokes, and 692 unspecified strokes. Compared with an intake of 100 g/day of milk, the multivariable-adjusted hazard ratios (95% confidence interval) of cerebral infarction were 1.05 (1.02–1.08) for 0 g/day, 0.97 (0.95–0.99) for 200 g/day, 0.96 (0.92–1.00) for 400 g/day, 0.98 (0.94–1.03) for 600 g/day, and 1.01 (0.94–1.07) for 800 g/day. Corresponding estimates for hemorrhagic stroke were 0.98 (0.91–1.05) for 0 g/day, 1.02 (0.97–1.07) for 200 g/day, 1.07 (0.98–1.17) for 400 g/day, 1.13 (1.02–1.25) for 600 g/day, and 1.19 (1.03–1.36) for 800 g/day. No associations were observed between milk consumption and total stroke or for fermented milk consumption and any of the stroke outcomes. Higher long-term milk consumption based on repeated measures of intake was weakly and non-linearly associated with cerebral infarction, and was directly associated with hemorrhagic stroke.

Ferroptosis in oligodendrocyte progenitor cells mediates white matter injury after hemorrhagic stroke

Oligodendrocyte progenitor cells (OPCs) differentiate to myelin-producing mature oligodendrocytes and enwrap growing or demyelinated axons during development and post central nervous diseases. Failure of remyelination owing to cell death or undifferentiation of OPCs contributes to severe neurologic deficits and motor dysfunction. However, how to prevent the cell death of OPCs is still poorly understood, especially in hemorrhagic diseases. In the current study, we injected autologous blood into the mouse lateral ventricular to study the hemorrhage-induced OPC cell death in vivo. The integrity of the myelin sheath of the corpus callosum was disrupted post intraventricular hemorrhage (IVH) assessed by using magnetic resonance imaging, immunostaining, and transmission electron microscopy. Consistent with the severe demethylation, we observed massive cell death of oligodendrocyte lineages in the periventricular area. In addition, we found that ferroptosis is the major cell death form in Hemin-induced OPC death by using RNA-seq analysis, and the mechanism was glutathione peroxidase 4 activity reduction-resulted lipid peroxide accumulation. Furthermore, inhibition of ferroptosis rescued OPC cell death in vitro, and in vivo attenuated IVH-induced white matter injury and promoted recovery of neurological function. These data demonstrate that ferroptosis is an essential form of OPC cell death in hemorrhagic stroke, and rescuing ferroptotic OPCs could serve as a therapeutic target for stroke and related diseases.

Ferrostatin-1 Polarizes Microglial Cells Toward M2 Phenotype to Alleviate Inflammation After Intracerebral Hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) is one of the most lethal stroke types and lacks effective therapeutic regimens. Recently, evidence has suggested the involvement of the ferroptosis inhibitor ferrostatin-1 (Fer-1) in the pathophysiological process of ICH. In this study, we examined the underlying mechanism.

METHODS

We induced an in vitro apoptosis model in organotypic hippocampal slice (OHS) using hemoglobin (Hb) and an in vivo ICH model using collagenase. OHSs were treated with MK-801, Fer-1, glutamate, and Hb to assess the impacts of Fer-1 on neuron apoptosis, glutathione peroxidase-4 activity, reactive oxygen species production, inflammation-related factors, expression of M1 markers and M2 markers, and the phagocytic function of microglial cells in vitro. Then, ICH mice were treated with Fer-1 and ruxolitinib to evaluate the effects of Fer-1-orchestrating janus kinase 1/signal transducer and activator of transcription 6 pathway on neurological function, brain water content, hematoma volume, the anti-inflammatory factor, M1 and M2 markers, and the phagocytic function of microglial cells in vivo.

RESULTS

Hb or glutamate facilitated glutathione peroxidase dysfunction, reactive oxygen species production, and neuronal apoptosis in OHSs, which was nullified by Fer-1. Fer-1 polarized microglial cells to the M2 phenotype, enhanced their phagocytic function, and prevented inflammation in Hb-induced OHSs. In the ICH mouse model, Fer-1 was found to improve neurological function and promote hematoma absorption. In addition, Fer-1 activated the Fer-1-orchestrating janus kinase 1/signal transducer and activator of transcription 6 pathway, which accelerated microglial M2 polarization, enhanced the phagocytic function of microglial cells, and restrained inflammation in ICH mice.

CONCLUSIONS

Overall, our findings suggest that Fer-1 may be a novel mechanism underlying microglial M2 polarization and inflammation after ICH.

Frequency, Predictors, Etiology, and Outcomes for Deep Intracerebral Hemorrhage without Hypertension

OBJECTIVES

Some patients with deep intracerebral hemorrhage (ICH) have a transient hypertensive response and they may be erroneously classified as secondary to hypertension. We investigated frequency, risk factors, and outcomes for patients with deep ICH without hypertension.

MATERIALS AND METHODS

We consecutively recruited patients with spontaneous ICH attending two Spanish stroke centers (January 2015-June 2019). Excluded were patients with lobar/infratentorial ICH and patients who died during hospitalization. We defined deep ICH without hypertension when the bleeding was in a deep structure, no requirement for antihypertensive agents during follow-up and no evident chronic hypertension markers evaluated by transthoracic echocardiography, 24 h ambulatory blood pressure monitoring and/or electrocardiography. We compared clinical, radiological, and 3-month functional outcome data for deep-ICH patients with hypertension versus those without hypertension.

RESULTS

Of 759 patients with ICH, 219 (mean age 69.6 ± 15.4 years, 54.8% men) met the inclusion criteria and 36 (16.4%) did not have hypertension. Of these 36 patients, 19 (52.7%) had a transient hypertensive response. Independent predictors of deep ICH without hypertension were age (adjusted OR:0.94;95%CI:0.91-0.96) and dyslipidemia (adjusted OR:0.27;95% CI:0.08-0.85). One third of deep ICH without hypertension were secondary to vascular malformations. Favorable outcomes (modified Rankin Scale 0-2) were more frequent in patients with deep ICH without hypertension compared to those with hypertension (70.9% vs 33.8%; p < 0.001).

CONCLUSION

Of patients with deep ICH, 16.4% were unrelated with hypertension, around half showed hypertensive response, and around a third had vascular malformations. We suggest studying hypertension markers and performing a follow-up brain MRI in those patients with deep ICH without prior hypertension.

Trigger Factors for Spontaneous Intracerebral Hemorrhage: A Case-Crossover Study

BACKGROUND AND PURPOSE

Whether certain activities can trigger spontaneous intracerebral hemorrhage (ICH) remains unknown. Insights into factors that trigger vessel rupture resulting in ICH improves knowledge on the pathophysiology of ICH. We assessed potential trigger factors and their risk for ICH onset.

METHODS

We included consecutive patients diagnosed with ICH between July 1, 2013, and December 31, 2019. We interviewed patients on their exposure to 12 potential trigger factors (eg, Valsalva maneuvers) in the (hazard) period soon before onset of ICH and their normal exposure to these trigger factors in the year before the ICH. We used the case-crossover design to calculate relative risks (RR) for potential trigger factors.

RESULTS

We interviewed 149 patients (mean age 64, 66% male) with ICH. Sixty-seven (45%) had a lobar hemorrhage, 60 (40%) had a deep hemorrhage, 19 (13%) had a cerebellar hemorrhage, and 3 (2%) had an intraventricular hemorrhage. For ICH in general, there was an increased risk within an hour after caffeine consumption (RR=2.5 [95% CI=1.8-3.6]), within an hour after coffee consumption alone (RR=4.8 [95% CI=3.3-6.9]), within an hour after lifting >25 kg (RR=6.6 [95% CI=2.2-19.9]), within an hour after minor head trauma (RR=10.1 [95% CI=1.7-60.2]), within an hour after sexual activity (RR=30.4 [95% CI=16.8-55.0]), within an hour after straining for defecation (RR=37.6 [95% CI=22.4-63.4]), and within an hour after vigorous exercise (RR=21.8 [95% CI=12.6-37.8]). Within 24 hours after flu-like disease or fever, the risk for ICH was also increased (RR=50.7 [95% CI=27.1-95.1]). Within an hour after Valsalva maneuvers, the RR for deep ICH was 3.5 (95% CI=1.7-6.9) and for lobar ICH the RR was 2.0 (95% CI=0.9-4.2).

CONCLUSIONS

We identified one infection and several blood pressure related trigger factors for ICH onset, providing new insights into the pathophysiology of vessel rupture resulting in ICH.

DNA Hypomethylation of DOCK1 Leading to High Expression Correlates with Neurologic Deterioration and Poor Function Outcomes after Spontaneous Intracerebral Hemorrhage

Objective

Spontaneous intracerebral hemorrhage (ICH) is a blood clot arising in the brain parenchyma in the absence of trauma or surgery and accounts for 10% to 15% of all strokes, leading to higher rates of mortality and morbidity than either ischemic stroke or subarachnoid hemorrhage. We sought to investigate the potential association of DOCK1 with neurological deficits and outcomes in patients with spontaneous ICH.

Methods

Identification of methylation-regulated differentially expressed genes (MeDEGs) between ICH patients and matched controls was performed by analyzing the raw data from the GSE179759 and GSE125512 datasets deposited in the Gene Expression Omnibus. A total of 114 patients who were admitted to our hospital for spontaneous ICH were retrospectively analyzed, with 108 healthy volunteers who had received physical examinations at the same period as controls. The mRNA expression of DOCK1 was determined by quantitative real-time polymerase chain reaction (qRT-PCR). The hematoma volume was calculated according to the Coniglobus formula. The severity of neurological deficits was evaluated using National Institutes of Health Stroke Scale (NIHSS) scores and function outcomes were evaluated by modified Rankin Scale (mRS) scores.

Results

A total of 15 MeDEGs between ICH patients and matched controls were identified. The mRNA expression of DOCK1 was remarkably higher in the serum samples of patients with spontaneous ICH than in the healthy controls. According to hematoma volume after ICH attack, small (<10 mL), medium (10 to 30 mL), and large (>30 mL) groups were arranged. The proportions of male patients and patients aged ≥60 years were significantly higher in the large group than in the small and medium groups (P < 0.05). The mRNA expression of DOCK1 was significantly higher in the large group than in the small and medium groups (P < 0.05). According to NIHSS scores, mild (NIHSS scores ≤15), moderate (NIHSS scores from 16 to 30), and severe (NIHSS scores from 31 to 45) groups were classified. It was observed that the severe group had higher proportions of male patients and patients aged ≥60 years than the mild and moderate groups (P < 0.05). The severe group exhibited a higher mRNA expression of DOCK1 than the mild and moderate groups (P < 0.05). According to mRS scores, higher proportions of male patients and patients aged ≥60 years were observed in the unfavorable group than the favorable group (P < 0.05). The patients in the unfavorable group showed an elevated DOCK1 mRNA expression compared to those in the favorable group (P < 0.05).

Conclusion

The study provided evidence that male gender, older age, and higher DOCK1 mRNA expression were related to higher admission hematoma volume, neurologic deterioration, and poor function outcomes in patients with spontaneous ICH.

Influence of hypertension classification on hypertensive intracerebral hemorrhage location

The authors sought to explore whether hypertension classification was risk factor for lobar and non‐lobar hypertensive intracerebral hemorrhage (HICH) and the prognosis in patients with hematoma. This retrospective cohort study was conducted on HICH patients admitted at the First Affiliated Hospital of Soochow University. Observations with first‐ever intracerebral hemorrhage (ICH) were recruited. The authors divided the brain image into three groups according to the location of ICH to predict whether there were significant differences between lobar and non‐lobar ICH. A Mann‐Whitney U test was used and this retrospective trial also compared the operation and mortality rates. Our cohort included 209 patients (73.7% male; median age:60.5±16.7). The overall incidence of lobar HICH was less than non‐lobar HICH (24.4% vs. 68.4%), 7.2% cases of mixed HICH was included in this analysis. In a Mann‐Whitney U test analyze, it indicated that there were significant differences in hypertension classification between lobar and non‐lobar HICH (Z = ‐3.3, p<.05). And the percentage of hematoma in lobar areas with relatively slightly high blood pressure (BP) (high normal and grade 1 hypertension) accounts for 52.9% versus 30.1% in non‐lobar areas. The increasing trends of the prevalent rate of lobar ICH with BP rising were not remarkable. The non‐lobar HICH showed a sharper increase in the condition of grade 3 hypertension compared with lobar HICH. During the period of research, the fatality of lobar hemorrhage was 2.9% versus 7.7% (non‐lobar). Besides, the fatality incidence of HICH with relatively slightly high BP (high normal and grade 1 hypertension) was lower than poorly controlled hypertensive patients (grade 2 and grade 3 hypertension). (8.0% vs. 15.7%). The increase of hypertension classification will aggravate the occurrence of non‐lobar ICH and positively corrected with BP, but not in lobar areas. It is essential to understand the distinction influence of hypertension classification between lobar and non‐lobar ICH.

Stroke Prevention After Intracerebral Hemorrhage: Where Are We Now?

PURPOSE OF REVIEW

Patients after intracerebral hemorrhage (ICH) are at high risk of both ischemic stroke and recurrent ICH, and stroke prevention after ICH is important to improve the long-term outcomes in this patient population. The objective of this article is to review the current guidelines on stroke prevention measures after ICH as well as the new findings and controversies for future guidance.

RECENT FINDINGS

Intensive blood pressure reduction might benefit ICH survivors significantly. Cholesterol levels and the risk of ICH have an inverse relationship, but statin therapy after ICH might be still beneficial. Anticoagulation in atrial fibrillation after ICH specifically with novel oral anticoagulants may be associated with better long-term outcomes. Left atrial appendage occlusion may be an alternative for stroke prevention in ICH survivors with atrial fibrillation for whom long-term anticoagulation therapy is contraindicated. While complete individualized risk assessment is imperative to prevent stroke after ICH, future research is required to address current controversies and knowledge gap in this topic.

Intracerebral Hemorrhage

PURPOSE OF REVIEW

Nontraumatic intracerebral hemorrhage (ICH) is the second most common type of stroke. This article summarizes the basic pathophysiology, classification, and management of ICH and discusses the available evidence on therapy for hematoma, hematoma expansion, and perihematomal edema.

RECENT FINDINGS

Current available data on potential therapeutic options for ICH are promising, although none of the trials have shown improvement in mortality rate. The literature available on reversal of anticoagulation and antiplatelet agents after an ICH and resumption of these medications is also increasing.

SUMMARY

ICH continues to have high morbidity and mortality. Advances in therapeutic options to target secondary brain injury from the hematoma, hematoma expansion, and perihematomal edema are increasing. Data on reversal therapy for anticoagulant-associated or antiplatelet-associated ICH and resumption of these medications are evolving.

Genetically Predicted Coffee Consumption and Risk of Alzheimer's Disease and Stroke

BACKGROUND

Observational studies have reported that coffee consumption was associated with Alzheimer's disease (AD) and stroke risk. However, the results are inconclusive.

OBJECTIVE

We aimed to evaluate whether genetically predicted coffee consumption is associated with AD and stroke using Mendelian randomization (MR) design.

METHODS

Summary-level data for AD (n = 54,162), ischemic stroke (n = 440,328), and intracerebral hemorrhage (ICH, n = 3,026) were adopted from publicly available databases. Summary-level data for coffee consumption were obtained from two genome-wide association studies, comprising up to 375,833 subjects.

RESULTS

Genetically predicted coffee consumption (cups/day) was associated with an increased risk of AD (OR = 1.26, 95%CI = 1.05-1.51). Moreover, genetically predicted 50%increase of coffee consumption was associated with an increased risk of ICH (OR: 2.27, 95%CI: 1.08-4.78) but a decreased risk of small vessel stroke (OR: 0.71, 95%CI: 0.51-0.996). Estimate for AD and ICH in FinnGen consortium is directionally consistent. Combined analysis of different databases further confirmed that genetically predicted coffee consumption was associated with an increased risk of AD and ICH. In the multivariable MR analysis, genetically predicted coffee consumption retained a stable effect with AD and ICH when adjusting for smoking (p < 0.05), while the association with AD attenuated when adjusting for alcohol use.

CONCLUSION

Our results indicate that genetically predicted coffee consumption may be associated with an increased risk of AD and ICH. The underlying biological mechanisms warrant further study.

Association of early glycemic change with short-term mortality in lobar and non-lobar intracerebral hemorrhage

The association between early glycemic change and short-term mortality in non-diabetic patients with acute intracerebral hemorrhage (ICH) is unclear. We retrospectively investigated non-diabetic patients with lobar (n = 262) and non-lobar ICH (n = 370). Each patient had a random serum glucose test on hospital admission and a fasting serum glucose test within the following 48 h. Hyperglycemia was defined as serum glucose ≥ 7.8 mmol/l. Four patterns were determined: no hyperglycemia (reference category), persistent hyperglycemia, delayed hyperglycemia, and decreasing hyperglycemia. Associations with 30-day mortality were estimated using Cox models adjusted for major features of ICH severity. Persistent hyperglycemia was associated with 30-day mortality in both lobar (HR 3.00; 95% CI 1.28–7.02) and non-lobar ICH (HR 4.95; 95% CI 2.20–11.09). In lobar ICH, 30-day mortality was also associated with delayed (HR 4.10; 95% CI 1.77–9.49) and decreasing hyperglycemia (HR 2.01, 95% CI 1.09–3.70). These findings were confirmed in Cox models using glycemic change (fasting minus random serum glucose) as a continuous variable. Our study shows that, in non-diabetic patients with ICH, early persistent hyperglycemia is an independent predictor of short-term mortality regardless of hematoma location. Moreover, in non-diabetic patients with lobar ICH, both a positive and a negative glycemic change are associated with short-term mortality.

Ambient air pollution and the risk of ischaemic and haemorrhagic stroke

Stroke is a leading cause of disability and the second most common cause of death worldwide. Increasing evidence suggests that air pollution is an emerging risk factor for stroke. Over the past decades, air pollution levels have continuously increased and are now estimated to be responsible for 14% of all stroke-associated deaths. Interpretation of previous literature is difficult because stroke was usually not distinguished as ischaemic or haemorrhagic, nor by cause. This Review summarises the evidence on the association between air pollution and the different causes of ischaemic stroke and haemorrhagic stroke, to clarify which people are most at risk. The risk for ischaemic stroke is increased after short-term or long-term exposure to air pollution. This effect is most pronounced in people with cardiovascular burden and stroke due to large artery disease or small vessel disease. Short-term exposure to air pollution increases the risk of intracerebral haemorrhage, a subtype of haemorrhagic stroke, whereas the effects of long-term exposure are less clear. Limitations of the current evidence are that studies are prone to misclassification of exposure, often rely on administrative data, and have insufficient clinical detail. In this Review, we provide an outlook on new research opportunities, such as those provided by the decreased levels of air pollution due to the current COVID-19 pandemic.

Prevalence of cerebral amyloid angiopathy: A systematic review and meta-analysis

Reported prevalence estimates of sporadic cerebral amyloid angiopathy (CAA) vary widely. CAA is associated with cognitive dysfunction and intracerebral hemorrhage, and linked to immunotherapy‐related side‐effects in Alzheimer's disease (AD). Given ongoing efforts to develop AD immunotherapy, accurate estimates of CAA prevalence are important. CAA can be diagnosed neuropathologically or during life using MRI markers including strictly lobar microbleeds. In this meta‐analysis of 170 studies including over 73,000 subjects, we show that in patients with AD, CAA prevalence based on pathology (48%) is twice that based on presence of strictly lobar cerebral microbleeds (22%); in the general population this difference is three‐fold (23% vs 7%). Both methods yield similar estimated prevalences of CAA in cognitively normal elderly (5% to 7%), in patients with intracerebral hemorrhage (19% to 24%), and in patients with lobar intracerebral hemorrhage (50% to 57%). However, we observed large heterogeneity among neuropathology and MRI protocols, which calls for standardized assessment and reporting of CAA.