Sex differences in stroke epidemiology: a systematic review

Temporal trends and disparities in atherosclerosis-associated cerebrovascular disease mortality in the United States, 1999-2020

BACKGROUND

Cerebrovascular disease (CEVD) accounts for the second leading cause of death worldwide. Despite recent advancements in treatment strategies, the prevalence and cost associated with CEVD are rising. Atherosclerosis significantly contributes to CEVD risk by restricting cerebral blood flow, leading to ischemic stroke. This study aims to analyze trends in atherosclerosis-associated CEVD mortality in the United States from 1999 to 2020 to inform targeted prevention and management strategies.

METHODS

We examined death certificates sourced from the CDC WONDER database, from 1999 to 2020 to identify atherosclerosis-associated CEVD mortality. Age-adjusted mortality rates (AAMRs) per 100,000 persons and annual percent changes were reported.

RESULTS

A total of 325,401 deaths occurred from CEVD among adults with atherosclerosis from 1999 to 2020 in the US. The overall AAMR initially inclined from 10.9 in 1999 to 12.6 in 2001, followed by a decrease to 4.2 in 2016, and then a rise till 2020 was observed. Males had consistently higher AAMRs than females throughout the study period (Men = 11.9 vs Women = 10.1). When stratified by race, AAMRs were highest among non-Hispanic (NH) Whites (6.9), followed by NH American Indian/Alaska Native (10.9), NH Blacks/African Americans (6.6), Hispanics (4.9), and lastly by Asian/Pacific Islanders (4.2). The Western region had the highest mortality (AAMR: 7.7).

CONCLUSION

The CEVD mortality rates of adults with atherosclerosis- are increasing in the adult U.S.

POPULATION

This underscores the need for increased screening, aggressive management, and subsequent surveillance of patients at risk.

The Effectiveness of Therapeutic Exercise Interventions With Virtual Reality on Balance and Walking Among Persons With Chronic Stroke: Systematic Review, Meta-Analysis, and Meta-Regression of Randomized Controlled Trials

BACKGROUND

Well-targeted balance, walking, and weight-shift training can improve balance capabilities in the chronic phase of stroke. There is an urgent need for a long-term approach to rehabilitation that extends beyond the acute and subacute phases, supporting participation without increasing the demand for health care staff.

OBJECTIVE

This study aims to evaluate the effectiveness of therapeutic exercise interventions with virtual reality (VR) training on balance and walking at the activity and participation levels in individuals with chronic stroke, compared with control groups receiving no treatment, conventional physical therapy, specific training, similar treatment, or identical treatment without VR.

METHODS

Studies were searched across 6 databases. The inclusion criteria were as follows: Adults aged 18 years or older with a stroke diagnosis for at least 6 months (population). Therapeutic exercises within a VR environment, using VR glasses or interactive games (intervention). Control groups without the use of VR (including no treatment, conventional physical therapy, specific training, similar treatment without VR, or identical treatment without the additional use of VR; comparison). We evaluated the Berg Balance Scale score, Functional Reach Test performance, Activities-specific Balance Confidence Scale score, Six-minute Walk Test, Two-minute Walk Test, 10-meter Walk Test results, and cadence (outcome measures). We investigated randomized controlled trials (study design). A meta-analysis and a meta-regression analysis were conducted to evaluate whether the content of VR interventions or control groups, as well as the level of VR immersion used, was related to balance or walking outcomes.

RESULTS

A total of 43 randomized controlled trials involving 1136 participants were included in this review. The use of VR training in therapeutic exercise interventions had a large effect on balance (standardized mean difference 0.51, 95% CI 0.29-0.72; P<.001) and a moderate effect on walking (standardized mean difference 0.31, 95% CI 0.09-0.53; P=.006) in individuals with chronic stroke, compared with pooled control groups (no treatment, conventional physical therapy, specific training, similar treatment, or identical treatment without the use of VR). According to the meta-regression findings, the content of VR interventions (P=.52), the type of control groups (P=.79), and the level of VR immersion (P=.82) were not significantly related to the pooled balance or walking outcomes. The GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) was moderate for balance and low for walking.

CONCLUSIONS

Therapeutic exercise training with VR had a positive, albeit moderate, effect on balance and a low impact on walking at the level of activity (capacity), even in the chronic phase of stroke, without serious side effects. The results are applicable to working-aged stroke rehabilitees who are able to walk without assistance. Further research is needed with defined VR methods and outcomes that assess performance at the level of real-life participation.

Undiagnosed major risk factors in acute ischaemic stroke patients in Qatar: analysis from the Qatar stroke registry

Objective

We examined the presentation to hospital, subtypes of ischaemic stroke for patients admitted to stroke services in Qatar and their 90-day prognosis based on the modified Rankin Scale (mRS) for those with diagnosed and undiagnosed diabetes, hypertension and dyslipidaemia.

Methods

We conducted a retrospective analysis of patients admitted with acute ischaemic stroke from January 2014 to April 2024. The mRS was dichotomised with favourable outcome (0-2) and unfavourable outcome (3-6).

Results

A total of 9479 patients were included in the study. Patients with a prior history of hypertension and dyslipidaemia and untreated/undiagnosed for these risk factors on admission were more likely to present with a lower National Institute of Health Stroke Scale (NIHSS) score at admission (p<0.001). These patients were also more likely to present with small vessel disease (SVD) or subcortical stroke (p<0.001). Multivariate analysis revealed that age (adjusted OR 1.05, 95% CI 1.04 to 1.06) and hypertension (adjusted OR 1.44, 95% CI 1.07 to 1.96) were more likely to have an mRS score of 3-6 at 90 days while males (adjusted OR 0.56, 95% CI 0.46 to 0.69), prior antidiabetic therapy (adjusted OR 0.52, 95% CI 0.34 to 0.79) and undiagnosed diabetes (adjusted OR 0.46, 95% CI 0.22 to 0.99) were protective against an mRS score of 3-6 at 90 days after adjusting for covariates.

Conclusion

Patients with a prior history of hypertension and dyslipidaemia and undiagnosed on admission are more likely to present with a lower NIHSS score but have a worse outcome at 90 days. The lower NIHSS may be explained by a higher frequency of SVD.

ACSL3 is a promising therapeutic target for alleviating anxiety and depression in Alzheimer's disease

Alzheimer's disease (AD), the leading cause of dementia, affects over 55 million people worldwide and is often accompanied by depression and anxiety. Both significantly impact patients' quality of life and impose substantial societal and economic burdens on healthcare systems. Identifying the complex regulatory mechanisms that contribute to the psychological and emotional deficits in AD will provide promising therapeutic targets. Biosynthesis of omega-3 (ω3) and omega-6 fatty acids (ω6-FA) through long-chain acyl-CoA synthetases (ACSL) is crucial for cell function and survival. This is due to ω3/6-FA's imperative role in modulating the plasma membrane, energy production, and inflammation. While ACSL dysfunction is known to cause heart, liver, and kidney diseases, the role of ACSL in pathological conditions in the central nervous system (e.g., depression and anxiety) remains largely unexplored. The impact of ACSLs on AD-related depression and anxiety was investigated in a mouse model of Alzheimer's disease (3xTg-AD). ACSL3 levels were significantly reduced in the hippocampus of aged 3xTg-AD mice (via capillary-based immunoassay). This reduction in ACAL3 was closely associated with increased depression and anxiety-like behavior (via forced swim, tail suspension, elevated plus maze, and sucrose preference test). Upregulation of ACSL3 via adenovirus in aged 3xTg-AD mice led to increased protein levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor C (VEGF-C) (via brain histology, capillary-based immunoassay), resulting in alleviation of depression and anxiety symptoms. The present study highlights a novel neuroprotective role of ACSL3 in the brain. Targeting ACSL3 will offer an innovative approach for treating AD-related depression and anxiety.

Etiologies of non-traumatic extremity compartment syndrome: A multi-center retrospective review

Determine the etiologies of non-traumatic extremity compartment syndrome (NTECS), understand the demographics of NTECS patients, describe their diagnostic workup and treatment, and establish their rate and cause of in-hospital mortality. This is a retrospective cohort study of all patients diagnosed with NTECS at two level 1 trauma centers between January 2006 and December 2019. Data pertaining to the etiology of NTECS, patient demographics, diagnostic and treatment modalities, and in-hospital mortality were collected from electronic medical records. A total of 572 patients were included in this study with an average age of 54±18 years. The etiologies of NTECS were categorized into one of seven groups: 233 hypercoagulable state, 113 found-down secondary to substance use, 68 hypocoaguable state, 58 perioperative positioning, 55 shock, 30 infection, and 15 intravenous/intraosseous (IV/IO) infiltration. Approximately 13 % of patients underwent a skin graft or flap procedures, while 13 % of patients required an extremity amputation. The in-hospital mortality was highest in patients who developed NTECS due to shock (58 %). The average in hospital-mortality for all NTECS etiologies was 20 %. While uncommon, many etiologies of NTECS exist and often manifest insidiously. 13% of patients who develop NTECS will require a skin graft / flap, or extremity amputation. 20 % of patients who develop NTECS die during their hospitalization. High clinical suspicion and future research in this field are necessary to improve clinical outcomes for these patients. Level IV: Retrospective review.

Translation and validation of the Persian version of the Stroke Self-Efficacy Questionnaire in stroke survivors

BACKGROUND

The Stroke Self-Efficacy Questionnaire (SSEQ) is a self-report scale that measures stroke survivors' self-efficacy and covers specific domains of functioning after stroke.

OBJECTIVES

We aimed to determine the validity and reliability of the Persian version of the SSEQ.

METHODS

This descriptive cross-sectional study included 124 stroke patients in the sub-acute phase (between 2 weeks and 3 months of stroke onset). The original SSEQ was translated to Persian and back-translated to English. Demographic, neurologic examination, 'Persian Stroke Self-Efficacy Questionnaire (SSEQ-P)', and 'General Self-Efficacy Scale' (GSE-10) data were collected. The reliability of the questionnaire was evaluated by test-retest assessment among 30 people with stroke at an interval of two weeks. Factor analysis was used to assess the validity of SSEQ-P. Cronbach's alpha assessed internal consistency in all participants. Statistical analysis was performed by SPSS software version 23 and SmartPLS version 3.

RESULTS

In this study, the mean of SSEQ scores was 87.99 ± 37.09. Content Validity Ratio (CVR) and Content Validity Index (CVI) were favorable. Convergent validity of the questionnaire was reported (r = 0.669) using GSE. Factor loadings of items in SSEQ ranged from 0.41 to 0.92. Validity indices (AVE = 0.75, SRMR = 0.07) showed that the single-factor model of the present study owns a favorable fit. Test-retest reliability and Cronbach's alpha values of SSEQ in the present study were calculated at 0.80 and 0.97, respectively.

CONCLUSIONS

The Persian version of the SSEQ depicted acceptable reliability and validity and can be utilized to evaluate the self-efficacy of patients with stroke.HIGHLIGHTSStroke Self-Efficacy Questionnaire (SSEQ) is a self-report scale that measures stroke survivors' self-efficacy.The Persian version of the SSEQ demonstrated acceptable reliability and validity and can be used in stroke patients.

Sex Differences in Neuropsychiatric Symptoms in Alpha-Synucleinopathies: A Systematic Review and Meta-Analysis

BACKGROUND

Alpha-synucleinopathies, such as Parkinson's disease (PD), Parkinson's disease dementia (PDD), and dementia with Lewy bodies (DLB), demonstrate sex differences with regard to prevalence, age of onset, and motor manifestations. Neuropsychiatric symptoms (NPS) are common early and late manifestations of these disorders.

OBJECTIVES

We aimed to describe sex differences in NPS across alpha-synucleinopathies.

METHODS

We searched Web of Science Core collection databases to identify observational studies published between January 1, 2000, and June 1, 2022, reporting the prevalence or severity of NPS among individuals with a diagnosis of PD, PDD, or DLB. Prevalence and severity were pooled for each NPS according to sex using random-effects models.

RESULTS

Two-hundred-and-forty studies, representing 796,026 participants (45% females), were included in the meta-analysis. Female sex was associated with a higher prevalence of anxiety (OR = 1.60 [95% CI: 1.40, 1.82]), depression (OR = 1.56 [1.45, 1.67]), fatigue (OR = 1.21 [1.02, 1.43]), and psychotic symptoms (OR = 1.26 [1.14, 1.40]) and more severe anxiety (g = 1.35 [95% CI: 0.58, 2.13]), depression (g = 1.57 [1.05, 2.08]), and fatigue (g = 0.86 [0.41, 1.32]), while male sex was associated with a higher prevalence of apathy (OR = 0.77 [0.63, 0.93]), impulse control disorders (OR = 0.67 [0.55, 0.82]), REM sleep behavior disorder (OR = 0.54 [0.42, 0.70]), hypersomnolence (OR = 0.67 [0.56, 0.80]), and suicide (OR = 0.30 [0.20, 0.44]).

CONCLUSIONS

NPS have different prevalences and severities in alpha-synucleinopathies according to sex. These findings support consideration of sex in the elaboration of clinical tools.

Physiological influences on neurovascular coupling: A systematic review of multimodal imaging approaches and recommendations for future study designs

In this review, we have amalgamated the literature, taking a multimodal neuroimaging approach to quantify the relationship between neuronal firing and haemodynamics during a task paradigm (i.e., neurovascular coupling response), while considering confounding physiological influences. Original research articles that used concurrent neuronal and haemodynamic quantification in humans (n ≥ 10) during a task paradigm were included from PubMed, Scopus, Web of Science, EMBASE and PsychINFO. Articles published before 31 July 2023 were considered for eligibility. Rapid screening was completed by the first author. Two authors completed the title/abstract and full-text screening. Article quality was assessed using a modified version of the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. A total of 364 articles were included following title/abstract and full-text screening. The most common combination was EEG/functional MRI (68.7%), with cognitive (48.1%) and visual (27.5%) tasks being the most common. The majority of studies displayed an absence/minimal control of blood pressure, arterial gas concentrations and/or heart rate (92.9%), and only 1.3% monitored these factors. A minority of studies restricted or collected data pertaining to caffeine (7.4%), exercise (0.8%), food (0.5%), nicotine (2.7%), the menstrual cycle (0.3%) or cardiorespiratory fitness levels (0.5%). The cerebrovasculature is sensitive to numerous factors; thus, to understand the neurovascular coupling response fully, better control for confounding physiological influences of blood pressure and respiratory metrics is imperative during study-design formulation. Moreover, further work should continue to examine sex-based differences, the influence of sex steroid hormone concentrations and cardiorespiratory fitness.

Sex disparity in stroke risk among patients with insomnia: a 19-year prospective cohort study

STUDY OBJECTIVES

Considering the increased prevalence and more severe manifestations of insomnia among females along with established sex differences in ischemic stroke (IS) occurrence, this research aimed to examine the potential effects of the interaction between insomnia and sex on the incidence and outcome of IS.

METHODS

We used data from the Korean Genome and Epidemiology Study. The main exposure variables were insomnia history and sex. The main outcome was the occurrence of IS observed in biennial follow-up surveys. Cox proportional regression analysis was performed to estimate the effects of insomnia and sex on IS incidence. We also conducted interaction analysis to investigate the interaction effects between insomnia and sex on IS incidence.

RESULTS

During 19 years of follow-up involving 8,933 individuals, we documented 370 cases of new-onset stroke (2.88 cases per 1,000 person-years). Cox proportional regression analysis showed that insomnia and female sex did not increase the risk of IS (hazard ratio: 1.13 [95% confidence interval: 0.86-1.51] and hazard ratio: 0.86 [95% confidence interval: 0.63-1.17], respectively). Interaction analysis demonstrated that stroke risk was increased only among females with insomnia (hazard ratio: 1.34 [95% confidence interval: 1.05-1.80]) compared with those without insomnia.

CONCLUSIONS

Our study highlights the significance of considering sex-specific factors when evaluating the relationship between insomnia and IS risk, particularly emphasizing the unique role of insomnia in IS risk among females.

CITATION

Jung E, Kim DK, Lee SY, Ryu HH. Sex disparity in stroke risk among patients with insomnia: a 19-year prospective cohort study. J Clin Sleep Med. 2024;20(10):1669-1674.

Sex differences in Wake-Up Stroke patients characteristics and outcomes

OBJECTIVES

Wake-up Stroke (WUS) accounts for about 25% of all ischemic strokes. Differences according to sex in the WUS subgroup has been poorly investigated so far, so we aimed to assess these differences by differentiating the enrolled population based on treatment administered.

MATERIALS & METHODS

We retrospectively analysed clinical and imaging data of WUS patients admitted to our hospital between November 2013 and December 2018 dividing them in two groups: rTPA-treated and non-rTPA treated group. To point out outcome differences we evaluated: NIHSS at 7 days or at discharge, mRS at discharge and ΔNIHSS.

RESULTS

We enrolled 149 WUS patients, 74 rTPA treated and 75 non-rTPA treated. Among rTPA treated patients, time from last known well (LKW) to Emergency Department (ED) admission was longer in females than males (610 vs 454 min), while females had a higher ΔNIHSS than males (5 vs 3). Finally, among non-rTPA treated patients, females were older than males (85 vs 79 years), had a higher pre-admission mRS (although very low in both cases), had a longer length of stay (17 vs 13 days) and shown a higher NIHSS at discharge (4 vs 2) compared to males.

CONCLUSIONS

Females not receiving thrombolytic treatment had worse functional outcome than males, showing a higher NIHSS at discharge but, in contrast, when treated with rTPA they showed better neurological recovery as measured by a greater ΔNIHSS. We emphasize the importance of a prompt recognition of WUS in females since they seem to benefit more from rTPA treatment.

Race, Ethnicity, and Gender Disparities in the Management and Outcomes of Critically Ill Adults with Acute Stroke

Racial, ethnicity and sex disparities are pervasive in the evaluation and acute care of ischemic stroke patients. Administration of intravenous thrombolysis and mechanical thrombectomy are the most critical steps in ischemic stroke treatment but compared to White patients, ischemic stroke patients from minority racial and ethnic groups are less likely to receive these potentially life-saving interventions. Sex and racial disparities in intracerebral hemorrhage or subarachnoid hemorrhage treatment have not been well studied.

Incidence and risk factor analysis of neovascular glaucoma following vitrectomy in patients with proliferative diabetic retinopathy

To investigate the incidence and risk factors for neovascular glaucoma (NVG) after vitrectomy in patients with proliferative diabetic retinopathy (PDR). Patients were categorized into two subgroups based on their treatment regimen: one group received vitrectomy only (Group 1), while the other received combined phacovitrectomy (Group 2). A comparative analysis was conducted to evaluate the distinguishing characteristics of the two groups. Kaplan-Meier survival analysis was used to determine the incidence of NVG following surgery. Furthermore, multivariate analysis using the Cox proportional hazards model was conducted to identify the risk factors associated with the development of NVG after surgery. A total of 484 eyes of 484 patients were included in the study. When comparing Group 1 with Group 2, a significant difference was observed in the occurrence of NVG. In Group 1, there were 10 cases of NVG (3.9%), whereas 29 cases of NVG occurred in Group 2 (12.71%). Male sex, high preoperative intraocular pressure (IOP), and combined phacovitrectomy were found to be associated with the occurrence of NVG following phacovitrectomy. Higher creatinine levels had a protective effect in preventing the development of NVG. Male sex, high preoperative IOP, and combined phacovitrectomy were associated with a high incidence of NVG. Explore strategies to prevent NVG is important when performing combined phacovitrectomy in patients with PDR.

Age at menopause and risk of ischaemic stroke: a systematic review and meta-analysis

AIMS

Despite ischaemic stroke having much importance as one of the top 10 causes of death in older women, there are limited data on age at menopause and ischaemic stroke. We performed a systematic review and meta-analysis to estimate the effect of age at menopause on ischaemic stroke.

METHODS AND RESULTS

We screened four databases (PubMed, Cochrane, Web of Science, and EMBASE databases) up to 17 July 2023. This systematic review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and was registered with PROSPERO (CRD42023444245). Data extraction and quality assessment were independently undertaken by two reviewers. A random-effects model was used for meta-analysis using Revman5.4 to calculate the risk ratio of the incidence of ischaemic stroke. Heterogeneity was assessed using I2. Meta-regression and assessment for bias were performed. Out of 725 records identified, 10 studies were included in the qualitative synthesis and the quantitative meta-analysis. The pooled incidence rate for ischaemic strokes which age at menopause before 43 years old was 1.22 [95% confidence interval (CI): 1.02-1.46]. The pooled incidence rate of early menopause was 1.26 (95% CI: 1.07-1.48) for ischaemic stroke. The incidence rate of ischaemic stroke for women with early menopause may be in an environment with a high incidence for a long time.

CONCLUSION

This meta-analysis suggests that early menopause is associated with an increased risk of ischaemic stroke. Age at onset of menopause before 43 years old may be the cut-off value of increased risk of ischaemic stroke.

Endothelial lincRNA-p21 alleviates cerebral ischemia/reperfusion injury by maintaining blood-brain barrier integrity

Blood-brain barrier (BBB) disruption is increasingly recognized as an early contributor to the pathophysiology of cerebral ischemia/reperfusion (I/R) injury, and is also a key event in triggering secondary damage to the central nervous system. Recently, long non-coding RNA (lncRNA) have been found to be associated with ischemic stroke. However, the roles of lncRNA in BBB homeostasis remain largely unknown. Here, we report that long intergenic non-coding RNA-p21 (lincRNA-p21) was the most significantly down-regulated lncRNA in human brain microvascular endothelial cells (HBMECs) after oxygen and glucose deprivation/reoxygenation (OGD/R) treatment among candidate lncRNA, which were both sensitive to hypoxia and involved in atherosclerosis. Exogenous brain-endothelium-specific overexpression of lincRNA-p21 could alleviate BBB disruption, diminish infarction volume and attenuate motor function deficits in middle cerebral artery occlusion/reperfusion (MCAO/R) mice. Further results showed that lincRNA-p21 was critical to maintain BBB integrity by inhibiting the degradation of junction proteins under MCAO/R and OGD/R conditions. Specifically, lincRNA-p21 could inhibit autophagy-dependent degradation of occludin by activating PI3K/AKT/mTOR signaling pathway. Besides, lincRNA-p21 could inhibit VE-cadherin degradation by binding with miR-101-3p. Together, we identify that lincRNA-p21 is critical for BBB integrity maintenance, and endothelial lincRNA-p21 overexpression could alleviate cerebral I/R injury in mice, pointing to a potential strategy to treat cerebral I/R injury.

Age- and Sex-Specific Analysis of Stroke Hospitalization Rates, Risk Factors, and Outcomes From German Nationwide Data

BACKGROUND

Significant age and sex differences have been reported at each stage of the stroke pathway, from risk factors to outcomes. However, there is some uncertainty in previous studies with regard to the role of potential confounders and selection bias. Therefore, using German nationwide administrative data, we aimed to determine the magnitude and direction of trends in age- or sex-specific differences with respect to admission rates, risk factors, and acute treatments of ischemic and hemorrhagic stroke.

METHODS

We obtained and analyzed data from the Research Data Centres of the Federal Statistical Office for the years 2010 to 2020 with regard to all acute stroke hospitalizations, risk factors, treatments, and in-hospital mortality, stratified by sex and stroke subtype. This database provides a complete national-level census of stroke hospitalizations combined with population census counts. All hospitalized patients ≥15 years with an acute stroke (diagnosis code: I60-64) were included in the analysis.

RESULTS

Over the 11-year study period, there were 3 375 157 stroke events; 51.2% (n=1 728 954) occurred in men. There were higher rates of stroke admissions in men compared with women for both ischemic (378.1 versus 346.7/100 000 population) and hemorrhagic subtypes (75.6 versus 65.5/100 000 population) across all age groups. The incidence of ischemic stroke admissions peaked in 2016 among women (354.0/100 000 population) and in 2017 among men (395.8/100 000 population), followed by a consistent decline from 2018 onward. There was a recent decline in hemorrhagic stroke admissions observed for both sexes, reaching its nadir in 2020 (68.9/100 000 for men; 59.5/100 000 for women). Female sex was associated with in-hospital mortality for both ischemic (adjusted odds ratio, 1.11 [1.09-1.12]; P<0.001) and hemorrhagic stroke (adjusted odds ratio, 1.18 [95% CI, 1.16-1.20]; P<0.001).

CONCLUSIONS

Despite improvements in stroke prevention and treatment pathways in the past decade, sex-specific differences remain with regard to hospitalization rates, risk factors, and mortality. Better understanding the mechanisms for these differences may allow us to develop a sex-stratified approach to stroke care.

Sex differences in clot, vessel and tissue characteristics in patients with a large vessel occlusion treated with endovascular thrombectomy

INTRODUCTION

To improve our understanding of the relatively poor outcome after endovascular treatment (EVT) in women we assessed possible sex differences in baseline neuroimaging characteristics of acute ischemic stroke patients with large anterior vessel occlusion (LVO).

PATIENTS AND METHODS

We included all consecutive patients from the MR CLEAN Registry who underwent EVT between 2014 and 2017. On baseline non-contrast CT and CT angiography, we assessed clot location and clot burden score (CBS), vessel characteristics (presence of atherosclerosis, tortuosity, size, and collateral status), and tissue characteristics with the Alberta Stroke Program Early Computed Tomography Score (ASPECTS). Radiological outcome was assessed with the extended thrombolysis in cerebral infarction score (eTICI) and functional outcome with the modified Rankin Scale score (mRS) at 90 days. Sex-differences were assessed with multivariable regression analyses with adjustments for possible confounders.

RESULTS

3180 patients were included (median age 72 years, 48% women). Clots in women were less often located in the intracranial internal carotid artery (ICA) (25%vs 28%, odds ratio (OR) 0.85;95% confidence interval: 0.73-1.00). CBS was similar between sexes (median 6, IQR 4-8). Intracranial (aOR 0.73;95% CI:0.62-0.87) and extracranial (aOR 0.64;95% CI:0.43-0.95) atherosclerosis was less prevalent in women. Vessel tortuosity was more frequent in women in the cervical ICA (aOR 1.89;95% CI:1.39-2.57) and women more often had severe elongation of the aortic arch (aOR 1.38;95% CI:1.00-1.91). ICA radius was smaller in women (2.3vs 2.5 mm, mean difference 0.22;95% CI:0.09-0.35) while M1 radius was essentially equal (1.6vs 1.7 mm, mean difference 0.09;95% CI:-0.02-0.21). Women had better collateral status (⩾50% filling in 62%vs 53% in men, aOR 1.48;95% CI:1.29-1.70). Finally, ASPECT scores were equal between women and men (median 9 in both sexes, IQR 8-10vs 9-10). Reperfusion rates were similar between women and men (acOR 0.94;95% CI:0.83-1.07). However, women less often reached functional independence than men (34%vs 46%, aOR 0.68;95% CI:0.53-0.86).

DISCUSSION AND CONCLUSION

On baseline imaging of this Dutch Registry, men and women with LVO mainly differ in vessel characteristics such as atherosclerotic burden, extracranial vessel tortuosity, and collateral status. These sex differences do not result in different reperfusion rates and are, therefore, not likely to explain the worse functional outcome in women after EVT.

Stroke Rehabilitation in India: Addressing Gender Inequities

Gender inequality has a significant and complex impact on stroke recovery and rehabilitation outcomes. Moreover, the influence of gender on post-stroke recovery is multifactorial, primarily biological, social, and behavioral issues. The recovery paths for men and women may have different outlines in relation to stroke occurrence, injury sites, and hormonal effects. These collectively influence the effective summarization of recovery strategies and outcomes. Furthermore, societal and cultural elements play a significant role in shaping access to resources, social support networks, and participation in rehabilitation programs, which consequently affect the outcomes. Considering the gender-specific nuances is important in developing effective rehabilitation strategies. Furthermore, effective stroke rehabilitation programs are needed to achieve equitable and improved recovery outcomes for all stroke survivors and to create inclusive interventions that consider these differences.

Identification of Disease-relevant, Sex-based Proteomic Differences in iPSC-derived Vascular Smooth Muscle

The prevalence of cardiovascular disease varies with sex, and the impact of intrinsic sex-based differences on vasculature is not well understood. Animal models can provide important insight into some aspects of human biology, however not all discoveries in animal systems translate well to humans. To explore the impact of chromosomal sex on proteomic phenotypes, we used iPSC-derived vascular smooth muscle cells from healthy donors of both sexes to identify sex-based proteomic differences and their possible effects on cardiovascular pathophysiology. Our analysis confirmed that differentiated cells have a proteomic profile more similar to healthy primary aortic smooth muscle than iPSCs. We also identified sex-based differences in iPSC- derived vascular smooth muscle in pathways related to ATP binding, glycogen metabolic process, and cadherin binding as well as multiple proteins relevant to cardiovascular pathophysiology and disease. Additionally, we explored the role of autosomal and sex chromosomes in protein regulation, identifying that proteins on autosomal chromosomes also show sex-based regulation that may affect the protein expression of proteins from autosomal chromosomes. This work supports the biological relevance of iPSC-derived vascular smooth muscle cells as a model for disease, and further exploration of the pathways identified here can lead to the discovery of sex-specific pharmacological targets for cardiovascular disease.

Significance

In this work, we have differentiated 4 male and 4 female iPSC lines into vascular smooth muscle cells, giving us the ability to identify statistically-significant sex-specific proteomic markers that are relevant to cardiovascular disease risk (such as PCK2, MTOR, IGFBP2, PTGR2, and SULTE1).

Activation of GPER-1 Attenuates Traumatic Brain Injury-Induced Neurological Impairments in Mice

This study aimed to investigate the effects of G1-activated G protein-coupled estrogen receptor 1 (GPER1) on neurological impairments and neuroinflammation in traumatic brain injury (TBI) mice. The controlled cortical impingement (CCI) method was used to establish the TBI model. The mice were subjected to ovariectomy (OVX) for two weeks prior to modeling. GPER1 agonist G1 was administered by intracerebroventricular injection. Brain tissue water content was detected by wet/dry method, and blood-brain barrier damage was detected by Evans blue extravasation. The neurological impairments in mice were evaluated by open field test, Y-maze test, nest-building test, object location memory test and novel object recognition test. Ionized calcium-binding adapter molecule 1 (Iba1) staining was used to indicate the activation of microglia. Expression of M1/M2-type microglia markers and inflammatory factors were evaluated by ELISA and qRT-PCR. The G1 administration significantly reduced cerebral edema and Evans blue extravasation at injury ipsilateral cortex and basal ganglia in TBI mice. Activation of GPER1 by G1 improved the anxiety behavior and the cognitive dysfunction of mice induced by TBI. G1 administration significantly decreased Iba1-positive staining cells and the mRNA levels of CD86, macrophage cationic peptide 1 (Mcp-1), nitric oxide synthase 2 (Nos2), interleukin 1 beta (IL-1β), and macrophage inflammatory protein-2 (MIP-2), while increased the mRNA levels of interleukin 10 (IL-10), arginase1 (Arg-1) and CD206. Activation of GPER1 through G1 administration has the potential to ameliorate cognitive dysfunction induced by TBI in mice. It may also inhibit the activation of M1 microglia in cortical tissue resulting from TBI, while promoting the activation of M2 microglia and contributing to the regulation of inflammatory responses.

J-shaped associations of pan-immune-inflammation value and systemic inflammation response index with stroke among American adults with hypertension: evidence from NHANES 1999-2020

Introduction

Stroke, a leading cause of death and disability worldwide, is primarily ischemic and linked to hypertension. Hypertension, characterized by systemic chronic inflammation, significantly increases stroke risk. This study explores the association of novel systemic inflammatory markers (SII, PIV, SIRI) with stroke prevalence in hypertensive U.S. adults using NHANES data.

Methods

We analyzed data from hypertensive participants in the NHANES 1999-2020 survey, excluding those under 20, pregnant, or with missing data, resulting in 18,360 subjects. Systemic inflammatory markers (SII, PIV, SIRI) were calculated from blood counts. Hypertension and stroke status were determined by self-report and clinical measurements. Covariates included sociodemographic, lifestyle, and medical history factors. Weighted statistical analyses and multivariate logistic regression models were used to explore associations, with adjustments for various covariates. Ethical approval was obtained from the NCHS Ethics Review Board.

Results

In a cohort of 18,360 hypertensive individuals (mean age 56.652 years), 7.25% had a stroke. Stroke patients were older, had lower PIR, and were more likely to be female, single, less educated, smokers, non-drinkers, physically inactive, and have diabetes and CHD. Multivariate logistic regression showed that SII was not significantly associated with stroke. However, PIV and SIRI were positively associated with stroke prevalence. Each unit increase in lnPIV increased stroke odds by 14% (OR = 1.140, p = 0.0022), and lnSIRI by 20.6% (OR = 1.206, p = 0.0144). RCS analyses confirmed J-shaped associations for lnPIV and lnSIRI with stroke. Stratified analyses identified gender and smoking as significant effect modifiers. Smoking was significantly associated with elevated PIV, SIRI, and SII levels, especially in current smokers.

Conclusion

Elevated PIV and SIRI levels significantly increase stroke prevalence in hypertensive individuals, notably among males and smokers. A predictive model with PIV, SIRI, and sociodemographic factors offers strong clinical utility.

Diverging Trends in Survival and Functional Outcome between Males and Females after Intracerebral Hemorrhage

BACKGROUND

Compared to ischemic stroke, sex differences in patient outcomes following intracerebral hemorrhage (ICH) are underreported. We aimed to determine sex differences in mortality and functional outcomes in a large, unselected Swedish cohort.

METHODS

In this observational study, data on 22,789 patients with spontaneous ICH registered in the Swedish Stroke Register between 2012 and 2019 were used to compare sex differences in 90-day mortality and functional outcome using multivariable Cox and logistic regression analyses, adjusting for relevant confounders. Multiple imputation was used to impute missing data.

RESULTS

The crude 90-day mortality rate was 36.7% in females (3,820/10,405) and 31.7% in males (3,929/12,384) (female hazard ratio [HR] 1.20 95% confidence interval [CI]: 1.15-1.25). In multivariable analysis, the HR for 90-day mortality following ICH in females was 0.89 (95% CI: 0.85-0.94). Age was an important driving factor for the effect of sex on mortality. After adjustment for age, vascular risk factors, and stroke severity, the 90-day functional outcome in pre-stroke independent patients was worse in females compared to males (odds ratio: 1.27 95% CI: 1.16-1.40).

CONCLUSION

In this large observational study, despite lower 90-day mortality, the female sex was independently associated with a worse functional outcome compared to males after ICH, even after adjusting for significant covariates. These diverging trends have not been previously reported for ICH. Given the observational design, our findings should be interpreted with caution, thus further external validation is warranted.

Sex Disparity in Stroke Mortality among Adults: A Time Series Analysis in the Greater Vitoria Region, Brazil (2000-2021)

The disparity between the sexes in stroke mortality has been demonstrated in people from different locations. The objective of this study was to analyze the disparity between sexes in stroke mortality in adults in the metropolitan area of Greater Vitoria between 2000 and 2021. Ecological time series design was conducted with a database of the Brazilian Health System Informatics Department. The annual percentage change and average annual percentage change were calculated through joinpoint regression. Pairwise comparisons using parallelism and coincidence tests were applied to compare temporal trends between men and women. Men had higher mortality rates in most years between 2000 and 2021. In contrast, women had higher proportional mortality values in all years evaluated from 2000 to 2021. The paired comparison revealed a disparity between the sexes in the proportional mortality time series (parallelism test: p = 0.003; coincidence test: p < 0.001). However, the time series of the mortality rates showed no disparity between the sexes (parallelism test: p = 0.114; coincidence test: p = 0.093). From 2000 to 2021, there was a disparity in proportional mortality from stroke between the sexes of the population in the metropolitan area of Greater Vitoria, Brazil. However, the time series of mortality rates between the sexes did not reveal any disparity in the study period.

Thrombus age does not differentiate between cardiogenic and atherosclerotic strokes

Objective

Interventional stroke therapy made thrombi available for histological analysis. Unfortunately, simple composition aspects such as erythrocyte versus fibrin/platelet rich did not allow a feasible allocation to thrombi's cardiac or carotid origin. Since the mentioned criteria represent characteristics of thrombus age, we used established histological criteria for determining thrombus age in patients who had an atherosclerotic (TOAST (Trial of Org 10172 in Acute stroke Treatment) 1) stroke versus patients who had a cardioembolic (TOAST 2) stroke.

Methods

We assessed prospectively data from stroke patients presenting with occlusion of the middle cerebral artery eligible for catheter-based intervention. Besides patient characteristics and stroke workup, extracted thrombi were classified into different age categories according to their cellular to fibrotic transition. Thrombi were collected in an erythrocyte lysing solution to reduce acute clotting effects. Statistics were done with a non-parametric Kolmogorov-Smirnov test.

Results

170 patients were included, of which 50 (38 men; 73±12 years) had a TOAST 1 and 99 (59 women; 75±10 years) had a TOAST 2 categorised stroke. Age, National Institutes of Health Stroke Score (13±7 vs 15±7), Alberta Stroke Program Early CT Score (9±3 vs 9±2), Thrombolysis in Cerebral Infarction Score (2.9±0.2 vs 2.9±0.3), modified Rankin Score on discharge (3.2±2 vs 3.2±2), number of vascular risk factors (0.9±1.4 vs 1.0±1.1) or time span between symptom onset to reperfusion (266±115 vs 260±128 min) remained non-significant. Also, thrombus age did not differ between the groups. The mean age of thrombi was 5-8 days. However, the male-female ratio differed significantly (p<0.0005) between groups, with more men in TOAST 1 group and more women in TOAST 2 group.

Conclusion

Age aspects of thrombi seem not feasible to allow reliable source allocation. However, the young age of thrombi points to a rapid detachment. The difference in sex relation is in line with previous reports.

Female Enrollment in Rehabilitation Trials: A Systematic Review of Reporting Sex and Female Participation in Randomized Controlled Trials of Poststroke Upper Extremity Rehabilitation Over 50 Years

OBJECTIVE

To systematically assess the reporting of sex and the percentage of female participants in randomized controlled trials (RCTs) examining interventions for the post-stroke rehabilitation of upper extremity (UE) motor disorders.

DATA SOURCES

CINAHL, Embase, PubMed, Scopus and Web of Science were searched from 1960 to April 1, 2021. Additional articles were identified using the Evidence-Based Review of Stroke Rehabilitation.

STUDY SELECTION

Studies were eligible for inclusion if they (1) were RCTs or crossovers published in English, (2) ≥50% of participants were diagnosed and affected by stroke, (3) included adults ≥18 years old, and (4) applied an intervention to the hemiparetic UE as the primary objective of the study.

DATA EXTRACTION

Two investigators independently screened the title and abstracts, and duplicates were removed. A full-text review was done for studies that met all inclusion criteria. Data were extracted using a custom data extraction template in Covidence and were transferred to online Excel (V16) for data management. Study characteristics and extracted variables were summarized using standard descriptive statistics. Data analyses were performed using SPSS (V29.0).

DATA SYNTHESIS

A total of 1276 RCTs met inclusion criteria, and of these, 5.2% did not report results on sex, accounting for 5.6% of participants. Women have been underrepresented in stroke RCTs, accounting for 38.8% of participants. Female participation was greater in the acute poststroke phase than in the chronic and subacute phases. Over almost 5 decades, there has been a small decrease in the proportion of female participants in these trials.

CONCLUSIONS

Evidence-based medicine for the treatment and prevention of stroke is guided by results from RCTs. Generalizability depends on sufficient representation in clinical trials. Stakeholders, such as funders and journal editors, play a key role in encouraging researchers to enroll enough of both sexes and to report the presence or absence of sex differences in RCTs.

Examining Sex Differences in Relationships Between Subjective and Objective Measures of Upper Extremity Motor Impairment in a Sample of Stroke Survivors

BACKGROUND AND PURPOSE

Rehabilitation professionals use subjective and objective outcome measures to assess stroke-related impact and impairment. Understanding if subjective and objective findings correlate among stroke survivors, especially if these associations differ between females and males, can inform care decisions.

METHODS

A retrospective cross-sectional design was used, with data selected from subacute to chronic stroke survivors on age, time since stroke, the hand domain from the Stroke Impact Scale version 3.0 (SIS-H), and the Fugl-Meyer Upper Extremity (FMUE) Assessment. Group differences were assessed for all outcomes based on sex and time poststroke. Separate correlations for females and males were performed between the subjective (SIS-H) and objective measures (FMUE) of upper limb function and impairment.

RESULTS

Data from 148 participants (44 females) were included in this study. SIS-H was significantly correlated with FMUE in both females and males ( P s ≤ 0.001). No significant differences were found between the groups' mean SIS-H or FMUE scores based on sex or time poststroke.

DISCUSSION AND CONCLUSIONS

Subjective and objective measures of physical functioning were correlated in both females and males. Although we found no sex differences in our primary outcomes, the sample size of females was disproportionately lower than the males. This is consistent with an ongoing problem in the stroke recovery research field, where females are often underrepresented and understudied, and where females who experience higher levels of impairment are less likely to participate in research.

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.

No Sex Differences in Mechanical Thrombectomy Time Metrics and Outcomes in Saskatchewan

BACKGROUND AND PURPOSE

Numerous studies have shown longer pre-hospital and in-hospital workflow times and poorer outcomes in women after acute ischemic stroke (AIS) in general and after endovascular treatment (EVT) in particular. We investigated sex differences in acute stroke care of EVT patients over 5 years in a comprehensive Canadian provincial registry.

METHODS

Clinical data of all AIS patients who underwent EVT between January 2017 and December 2022 in the province of Saskatchewan were captured in the Canadian OPTIMISE registry and supplemented with patient data from administrative data sources. Patient baseline characteristics, transport time metrics, and technical EVT outcomes between female and male EVT patients were compared.

RESULTS

Three-hundred-three patients underwent EVT between 2017 and 2022: 144 (47.5%) women and 159 (52.5%) men. Women were significantly older (median age 77.5 [interquartile range: 66-85] vs.71 [59-78], p < 0.001), while men had more intracranial internal carotid artery occlusions (48/159 [30.2%] vs. 26/142 [18.3%], p = 0.03). Last-known-well to comprehensive stroke center (CSC)-arrival time (median 232 min [interquartile range 90-432] in women vs. 230 min [90-352] in men), CSC-arrival-to-reperfusion time (median 108 min [88-149] in women vs. 102 min [77-141] in men), reperfusion status (successful reperfusion 106/142 [74.7%] in women vs. 117/158 [74.1%] in men) as well as modified Rankin score at 90 days did not differ significantly. This held true after adjusting for baseline variables in multivariable analyses.

CONCLUSION

While women undergoing EVT in the province of Saskatchewan were on average older than men, they were treated just as fast and achieved similar technical and clinical outcomes compared to men.

Effects of Lower Limb Proprioceptive Training on Balance and Trunk Control Among the Adult Stroke Population

Background and objective Balance and trunk control are major concerns among older adults during stroke rehabilitation. Loss of proprioception in the affected limb has a greater influence on motor learning and reeducation during balance training. Available studies stress the relevance of strength and functional training in regaining balance and trunk control. Proprioception training, in addition to available rehabilitation, can optimize the balance among this population. Our study aimed to find out the effects of proprioceptive training on balance and trunk control among the chronic stroke population. Methodology Out of 45 subjects enrolled at the Indian Head Injury Foundation, New Delhi, India, 30 subjects were selected based on selection criteria and randomized into two groups using the chit method, with 15 subjects in each group. The control group received conventional training, which included a range of motion, stretching, and strengthening exercises, while the intervention group received additional proprioceptive training five days per week for four consecutive weeks. Subjects were assessed on the Berg Balance Scale and Trunk Control Test for balance and trunk control on day one and after four weeks. A paired t-test was used to analyze the difference within the groups, and unpaired t-tests were used between the groups, keeping p < 0.05 as a significance level. Results After four weeks of intervention, statistically significant improvements were seen in the balance and trunk control groups, with p < 0.05 in both groups. However, a significant improvement in balance was observed in the experimental group when compared across groups (p = 0.001), whereas no statistically significant improvement in trunk control was found (p = 0.061). Conclusion We conclude that proprioceptive training and conventional physiotherapy both help to improve balance. Proprioceptive training is better for improving balance, but it has no significant effects on trunk control. It is likely that an extended intervention time or a different form of intervention may be required to achieve substantial gains in these areas. Future research might look at other outcome measures or the impacts of other types of therapies to see which ones are most helpful at increasing trunk control.

Exploring Relationships of Heart Rate Variability, Neurological Function, and Clinical Factors with Mortality and Behavioral Functional Outcome in Patients with Ischemic Stroke

Ischemic stroke is a leading cause of mortality and disability. The relationships of heart rate variability (HRV) and stroke-related factors with mortality and functional outcome are complex and not fully understood. Understanding these relationships is crucial for providing better insights regarding ischemic stroke prognosis. The objective of this study is to examine the relationship between HRV, neurological function, and clinical factors with mortality and 3-month behavioral functional outcome in ischemic stroke. We prospectively collected the HRV data and monitored the behavioral functional outcome of patients with ischemic stroke. The behavioral functional outcome was represented by a modified Rankin Scale (mRS) score. This study population consisted of 58 ischemic stroke patients (56.9% male; mean age 70) with favorable (mRS score ≤ 2) and unfavorable (mRS score ≥ 3) outcome. The analysis indicated that the median of the mean RR interval (RR mean) showed no statistical difference between mortality groups. Conversely, the median of the RR mean had significant association with unfavorable outcome (OR = 0.989, p = 0.007). Lower hemoglobin levels had significant association with unfavorable outcome (OR = 0.411, p = 0.010). Higher National Institute of Health Stroke Scale (NIHSS) score at admission had significant association with unfavorable outcome (OR = 1.396, p = 0.002). In contrast, age, stroke history, NIHSS score at admission, and hemoglobin showed no significant association with mortality in ischemic stroke. These results imply that HRV, as indicated by the median of RR mean, alongside specific clinical factors and neurological function at admission (measured by NIHSS score), may serve as potential prognostic indicators for 3-month behavioral functional outcome in ischemic stroke.

Sex differences in modifiable risk factors for stroke incidence and recurrence: the UCC-SMART study

BACKGROUND AND PURPOSE

Risk factors for stroke differ between women and men in general populations. However, little is known about sex differences in secondary prevention. We investigated if sex interacted with modifiable risk factors for stroke in a large arterial disease cohort.

METHODS

Within the prospective UCC-SMART study, 13,898 patients (35% women) with atherosclerotic disease or high-risk factor profile were followed up to 23 years for stroke incidence or recurrence. Hypertension, smoking, diabetes, overweight, dyslipidemia, high alcohol use, and physical inactivity were studied as risk factors. Association between these factors and ischemic and hemorrhagic stroke incidence or recurrence was studied in women and men using Cox proportional hazard models and Poisson regression models. Women-to-men relative hazard ratios (RHR) and rate differences (RD) were estimated for each risk factor. Left-truncated age was used as timescale.

RESULTS

The age-adjusted stroke incidence rate was lower in women than men (3.9 vs 4.4 per 1000 person-years), as was the age-adjusted stroke recurrence rate (10.0 vs 11.7). Hypertension and smoking were associated with stroke risk in both sexes. HDL cholesterol was associated with lower stroke incidence in women but not in men (RHR 0.49; CI 0.27-0.88; and RD 1.39; CI - 1.31 to 4.10). Overweight was associated with a lower stroke recurrence in women but not in men (RHR 0.42; CI 0.23-0.80; and RD 9.05; CI 2.78-15.32).

CONCLUSIONS

In high-risk population, sex modifies the association of HDL cholesterol on stroke incidence, and the association of overweight on stroke recurrence. Our findings highlight the importance of sex-specific secondary prevention.

Sex differences in stroke reperfusion therapy in Aotearoa (New Zealand)

BACKGROUND AND AIMS

Stroke is a leading cause of death in Aotearoa (New Zealand), and stroke reperfusion therapy is a key intervention. Sex differences in stroke care have previously been asserted internationally. This study assessed potential differences in stroke reperfusion rates and quality metrics by sex in Aotearoa (New Zealand).

METHODS

This study used data from three overlapping sources. The National Stroke Reperfusion Register provided 4-year reperfusion data from 2018 to 2021 on all patients treated with reperfusion therapy (intravenous thrombolysis and thrombectomy), including time delays, treatment rates, mortality and complications. Linkage to Ministry of Health administrative and REGIONS Care study data provided an opportunity to control for confounders and explore potential mechanisms. T-test and Wilcoxon rank-sum analyses were used for continuous variables, while the chi-squared test and logistic regression were used for comparing dichotomous variables.

RESULTS

Fewer women presented with ischaemic stroke (12 186 vs 13 120) and were 4.2 years older than men (median (interquartile range (IQR)) 79 (68-86) vs 73 (63-82) years). Women were overall less likely to receive reperfusion therapy (13.9% (1704) vs 15.8% (2084), P < 0.001) with an adjusted odds ratio of 0.83 (0.77-0.90), P < 0.001. The adjusted odds ratio for thrombolysis was lower for women (0.82 (0.76-0.89), P < 0.001), but lower rates of thrombectomy fell just short of statistical significance ((0.89 (0.79-1.00), P = 0.05). There were no significant differences in complications, delays or documented reasons for non-thrombolysis.

CONCLUSIONS

Women were less likely to receive thrombolysis, even after adjusting for age and stroke severity. We found no definitive explanation for this disparity.

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.

Sex differences in the correlation between white matter hyperintensity and 3-month outcome in acute stroke patients

Background

The severity of white matter hyperintensities (WMH) has been shown to be an independent predictor of poor stroke outcome, but the effect of sex on this correlation has not been investigated further. Therefore, the purpose of our study was to assess whether there was a sex difference between the severity of WMH and poor stroke outcome.

Methods

This retrospective study included 449 patients with acute ischemic stroke (AIS) who received intravenous thrombolysis. WMH severity was graded based on the Fazekas scale. The association between WMH severity and stroke outcome was explored through multivariable regression analyses in men and women.

Results

Among women, when dividing WMH severity into tertiles, T3 (Fazekas scale >3) had a 5.334 times higher risk for unfavorable outcomes than T1 (Fazekas scale <2) (p-trend = 0.026) in the adjusted model. In addition, moderate-severe WMH (Fazekas scale 3-6) had a 3.391 (1.151-9.991) times higher risk than none-mild WMH (Fazekas scale 0-2) (p = 0.027).

Conclusions

The risk of unfavorable outcomes increased proportionally with the enlargement of the WMH severity in females, suggesting the sex-specific value of the WMH severity in optimizing the risk stratification of stroke.

Sex Differences in Severity and Risk Factors for Ischemic Stroke in Patients With Hyperlipidemia

Objective

This study aims to determine sex differences in poststroke hypertriglyceridemia (serum triglyceride levels ⩾ 200 mg/dl) and high stroke severity in ischemic stroke patients.

Method

Our study analyzed data from 392 males and 373 females with hypertriglyceridemia. Stroke severity on admission was measured using the National Institute of Health Stroke Scale (NIHSS) with a value ⩽7 indicating a more favorable post-stroke prognosis while a score of >7 indicates poorer post-stroke outcomes. Logistic regression models adjusted for demographic and risk factors. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for each clinical risk factor were used to predict the increasing odds of an association of a specific clinical baseline risk factor with the male or female AIS with hypertriglyceridemia.

Results

In the adjusted analysis, male patients with hypertriglyceridemia, diastolic blood pressure (OR = 1.100, 95% CI, 1.034-1.171, P = .002), and Ischemic stroke mortality (OR = 6.474, 95% CI, 3.262-12.847, P < .001) were significantly associated with increased stroke severity. In female patients with hypertriglyceridemia, age (OR = 0.920, 95% CI, 0.866-0.978, P = .008) was associated with reduced stroke severity, while ischemic stroke mortality score (OR = 37.477, 95% CI, 9.636-145.756, P < .001) was associated with increased stroke severity.

Conclusion

Increased ischemic stroke mortality risk score was associated with increased severity in both male and female AIS patients with hypertriglyceridemia. Our findings provide information about sex differences in specific risk factors that can be managed to improve the care of male and female ischemic stroke patients with hypertriglyceridemia.

The impact of sex on stroke care: From epidemiology to outcome

BACKGROUND

Carotid stenosis and atrial fibrillation are key risk factors for development of hemispheric strokes. In this review we aim to identify sex-specific differences in the pathophysiology and treatment of these risk factors and areas for future study.

KEY FINDINGS

Women are underrepresented in research studies of stroke in patients with carotid disease and atrial fibrillation. However, key differences have been found between men and women that suggest that the development of carotid disease and atrial fibrillation occur at later stages of life and are associated with higher severity of stroke. Some treatments, including surgical treatment, seem to have different rates of efficacy and women and women are at higher risk of surgical complications. This suggests that treatment recommendations may need to be sex specific.

CONCLUSION

Efforts should be made to address research and treatment gaps in women with stroke risk factors. This may lead to the development of sex-specific recommendations for stroke prevention and treatment.

Importance of sex and gender differences in enrollment and interpretation of stroke clinical trials

OBJECTIVES

This review aims to reinforce the importance of improving sex balance in preclinical trials and sex and gender diversity and proportional balance in clinical trials enrollment and how this influences interpretation of stroke clinical trials. It also aims to identify strategies for improvement in data collection.

MATERIALS AND METHODS

A PubMed search was conducted of publications in English, using MeSH terms sex, sex characteristics, gender identity, transgender, gender-nonconforming persons, clinical trials as topic, stroke. Of 249 search results, 217 were human or animal studies related to stroke, the majority of which were reviews, secondary analyses of stroke clinical trials, meta analyses, or retrospective studies, subject to the methods of sex and gender acquisition per the primary data source. Articles were reviewed, noting inclusion or absence of sex and gender definitions and trial design. Selected articles were supplemented with United States Food and Drug Administration, National Institutes of Health, and National Academy of Science, Engineering, and Medicine publications.

RESULTS

The majority of preclinical studies continue to report sex as a binary variable, and the majority of stroke clinical trials report sex and gender as interchangeable and binary. Mindful trial design and statistical analysis can improve accuracy in the interpretation of sex and gender differences. Guidance exists to improve reporting on currently accepted sex and gender definitions, recommended data collection instruments, and appropriate statistical analyses.

CONCLUSIONS

Despite acknowledgement of having failed to achieve diverse and proportionally balanced enrollment, sex and gender imbalance across the research continuum remains prevalent. Responsible incorporation of sex and gender in stroke clinical trials can be achieved through thoughtful study design, use of contemporary sex and gender definitions, inclusive prospective data collection, balanced enrollment with prespecified goals, and appropriate statistical analysis.

Sex Differences in Case Fatality of Aneurysmal Subarachnoid Hemorrhage: A Systematic Review

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (SAH) is more common in women than in men, contrary to most cardiovascular diseases. However, it is unclear whether the case fatality rate (CFR) of SAH also differs by sex. Thus, we performed a systematic review to address the relationship between sex and SAH CFRs.

METHODS

We conducted a systematic literature search in PubMed, Scopus, and Cochrane library databases. We focused on population-based studies that included both nonhospitalized and hospitalized SAHs and had either reported 1-month (28-31 day) SAH CFRs separately for men and women or calculated risk estimates for SAH CFR by sex. For quality classification, we used the Cochrane Collaboration Handbook and Critical Appraisal Skills Program guidelines. We pooled the study cohorts and calculated relative risk ratios (RRs) with 95% confidence intervals (CIs) for SAH death between women and men using a random-effects meta-analysis model.

RESULTS

The literature search yielded 5,592 initial publications, of which 33 study cohorts were included in the final review. Of the 33 study cohorts, only three reported significant sex differences, although the findings were contradictory. In the pooled analysis of all 53,141 SAH cases (60.3% women) from 26 countries, the 1-month CFR did not differ (RR = 0.99 [95% CI: 0.93-1.05]) between women (35.5%) and men (35.0%). According to our risk-of-bias evaluation, all 33 study cohorts were categorized as low quality. The most important sources of bias risks were related to the absence of proper confounding control (all 33 study cohorts), insufficient sample size (27 of 33 study cohorts), and poor/unclear diagnostic accuracy (27 of 33 study cohorts).

CONCLUSION

Contrary to SAH incidence rates, the SAH CFRs do not seem to differ between men and women. However, since none of the studies were specifically designed to examine the sex differences in SAH CFRs, future studies on the topic are warranted.

Synergistic efficacy of repetitive peripheral magnetic stimulation on central intermittent theta burst stimulation for upper limb function in patients with stroke: a double-blinded, randomized controlled trial

BACKGROUND

Non-invasive techniques such as central intermittent theta burst stimulation (iTBS) and repetitive peripheral magnetic stimulation (rPMS) have shown promise in improving motor function for patients with stroke. However, the combined efficacy of rPMS and central iTBS has not been extensively studied. This randomized controlled trial aimed to investigate the synergistic effects of rPMS and central iTBS in patients with stroke.

METHOD

In this study, 28 stroke patients were randomly allocated to receive either 1200 pulses of real or sham rPMS on the radial nerve of the affected limb, followed by 1200 pulses of central iTBS on the ipsilesional hemisphere. The patients received the intervention for 10 sessions over two weeks. The primary outcome measures were the Fugl-Meyer Assessment-Upper Extremity (FMA-UE) and the Action Research Arm Test (ARAT). Secondary outcomes for activities and participation included the Functional Independence Measure-Selfcare (FIM-Selfcare) and the Stroke Impact Scale (SIS). The outcome measures were assessed before and after the intervention.

RESULTS

Both groups showed significant improvement in FMA-UE and FIM-Selfcare after the intervention (p < 0.05). Only the rPMS + iTBS group had significant improvement in ARAT-Grasp and SIS-Strength and activity of daily living (p < 0.05). However, the change scores in all outcome measures did not differ between two groups.

CONCLUSIONS

Overall, the study's findings suggest that rPMS may have a synergistic effect on central iTBS to improve grasp function and participation. In conclusion, these findings highlight the potential of rPMS as an adjuvant therapy for central iTBS in stroke rehabilitation. Further large-scale studies are needed to fully explore the synergistic effects of rPMS on central iTBS.

TRIAL REGISTRATION

This trial was registered under ClinicalTrials.gov ID No.NCT04265365, retrospectively registered, on February 11, 2020.

Out of the core: the impact of focal ischemia in regions beyond the penumbra

The changes in the necrotic core and the penumbra following induction of focal ischemia have been the focus of attention for some time. However, evidence shows, that ischemic injury is not confined to the primarily affected structures and may influence the remote areas as well. Yet many studies fail to probe into the structures beyond the penumbra, and possibly do not even find any significant results due to their short-term design, as secondary damage occurs later. This slower reaction can be perceived as a therapeutic opportunity, in contrast to the ischemic core defined as irreversibly damaged tissue, where the window for salvation is comparatively short. The pathologies in remote structures occur relatively frequently and are clearly linked to the post-stroke neurological outcome. In order to develop efficient therapies, a deeper understanding of what exactly happens in the exo-focal regions is necessary. The mechanisms of glia contribution to the ischemic damage in core/penumbra are relatively well described and include impaired ion homeostasis, excessive cell swelling, glutamate excitotoxic mechanism, release of pro-inflammatory cytokines and phagocytosis or damage propagation via astrocytic syncytia. However, little is known about glia involvement in post-ischemic processes in remote areas. In this literature review, we discuss the definitions of the terms "ischemic core", "penumbra" and "remote areas." Furthermore, we present evidence showing the array of structural and functional changes in the more remote regions from the primary site of focal ischemia, with a special focus on glia and the extracellular matrix. The collected information is compared with the processes commonly occurring in the ischemic core or in the penumbra. Moreover, the possible causes of this phenomenon and the approaches for investigation are described, and finally, we evaluate the efficacy of therapies, which have been studied for their anti-ischemic effect in remote areas in recent years.

Do stroke services still show sex differences? A multicenter study

BACKGROUND

The issue of sex differences in stroke has gained concern in the past few years. However, multicenter studies are still required in this field. This study explores sex variation in a large number of patients and compares stroke characteristics among women in different age groups and across different countries.

METHODS

This multicenter retrospective cross-sectional study aimed to compare sexes regarding risk factors, stroke severity, quality of services, and stroke outcome. Moreover, conventional risk factors in women according to age groups and among different countries were studied.

RESULTS

Eighteen thousand six hundred fifty-nine patients from 9 countries spanning 4 continents were studied. The number of women was significantly lower than men, with older age, more prevalence of AF, hypertension, and dyslipidemia. Ischemic stroke was more severe in women, with worse outcomes among women (p: < 0.0001), although the time to treatment was shorter. Bridging that was more frequent in women (p:0.002). Analyzing only women: ischemic stroke was more frequent among the older, while hemorrhage and TIA prevailed in the younger and stroke of undetermined etiology. Comparison between countries showed differences in age, risk factors, type of stroke, and management.

CONCLUSION

We observed sex differences in risk factors, stroke severity, and outcome in our population. However, access to revascularization was in favor of women.

Neutrophils and Neutrophil Extracellular Traps Cause Vascular Occlusion and Delayed Cerebral Ischemia After Subarachnoid Hemorrhage in Mice

BACKGROUND

After subarachnoid hemorrhage (SAH), neutrophils are deleterious and contribute to poor outcomes. Neutrophils can produce neutrophil extracellular traps (NETs) after ischemic stroke. Our hypothesis was that, after SAH, neutrophils contribute to delayed cerebral ischemia (DCI) and worse outcomes via cerebrovascular occlusion by NETs.

METHODS

SAH was induced via endovascular perforation, and SAH mice were given either a neutrophil-depleting antibody, a PAD4 (peptidylarginine deiminase 4) inhibitor (to prevent NETosis), DNAse-I (to degrade NETs), or a vehicle control. Mice underwent daily neurological assessment until day 7 and then euthanized for quantification of intravascular brain NETs (iNETs). Subsets of mice were used to quantify neutrophil infiltration, NETosis potential, iNETs, cerebral perfusion, and infarction. In addition, NET markers were assessed in the blood of aneurysmal SAH patients.

RESULTS

In mice, SAH led to brain neutrophil infiltration within 24 hours, induced a pro-NETosis phenotype selectively in skull neutrophils, and caused a significant increase in iNETs by day 1, which persisted until at least day 7. Neutrophil depletion significantly reduced iNETs, improving cerebral perfusion, leading to less neurological deficits and less incidence of DCI (16% versus 51.9%). Similarly, PAD4 inhibition reduced iNETs, improved neurological outcome, and reduced incidence of DCI (5% versus 30%), whereas degrading NETs marginally improved outcomes. Patients with aneurysmal SAH who developed DCI had elevated markers of NETs compared with non-DCI patients.

CONCLUSIONS

After SAH, skull-derived neutrophils are primed for NETosis, and there are persistent brain iNETs, which correlated with delayed deficits. The findings from this study suggest that, after SAH, neutrophils and NETosis are therapeutic targets, which can prevent vascular occlusion by NETs in the brain, thereby lessening the risk of DCI. Finally, NET markers may be biomarkers, which can predict which patients with aneurysmal SAH are at risk for developing DCI.

Gender Differences in Procedural Clinical Complications and Outcomes of Intracranial Aneurysms: Analysis of the Stroke Thrombectomy and Aneurysm Registry

BACKGROUND AND OBJECTIVES

Some studies have shown that female patients had a poorer prognosis after endovascular treatment for ruptured intracranial aneurysm than male patients. However, data have been sparse regarding differences in the periprocedural and perioperative complication rate with ruptured and unruptured intracranial aneurysms.

METHODS

This retrospective cohort study used data from the Stroke Thrombectomy and Aneurysm Registry, a database of 9 institutions in the United States, Europe, and Asia. The study presented intracranial aneurysms after microsurgical and/or endovascular treatment from January 1, 2013, to December 31, 2022. The primary outcome was incidence of periprocedural cerebral infarction. Secondary outcomes were periprocedural intracranial hemorrhage, periprocedural mortality, perioperative vasospasm, and functional outcome at 90 days after procedure.

RESULTS

Among 3342 patients with aneurysm, 2447 were female and 857 were male, and the mean age of female and male patients was 59.6 and 57.1 years, respectively. Current smoker, family history of aneurysm, and ruptured aneurysm were observed in 23.5% vs 35.7 %, 10.8 % vs 5.7%, and 28.2% vs 40.5% of female and male patients, respectively. In female patients, internal carotid artery aneurysms were more commonly observed (31.1% vs 17.3%); however, anterior cerebral artery aneurysms were less commonly observed (18.5% vs 33.8%) compared with male patients. Periprocedural cerebral infarction rate was lower in female than male patients (2.4% vs 4.4%; P = .002). The adjusted odds ratio of primary outcome of female to male patients was 0.72 (95% CI, 0.46-1.12). Incidence of periprocedural intracranial hemorrhage and periprocedural mortality and perioperative symptomatic vasospasm and functional outcome was similar in both groups. In subgroup analysis, periprocedural cerebral infarction due to microsurgical treatment occurred frequently in male patients while incidence in endovascular treatment was similar in both groups (interaction P = .005).

CONCLUSION

This large multicenter registry of patients undergoing intracranial aneurysm treatment found that female patients were not at increased risk of perioperative complications.

Similarities in the Electrographic Patterns of Delayed Cerebral Infarction and Brain Death After Aneurysmal and Traumatic Subarachnoid Hemorrhage

While subarachnoid hemorrhage is the second most common hemorrhagic stroke in epidemiologic studies, the recent DISCHARGE-1 trial has shown that in reality, three-quarters of focal brain damage after subarachnoid hemorrhage is ischemic. Two-fifths of these ischemic infarctions occur early and three-fifths are delayed. The vast majority are cortical infarcts whose pathomorphology corresponds to anemic infarcts. Therefore, we propose in this review that subarachnoid hemorrhage as an ischemic-hemorrhagic stroke is rather a third, separate entity in addition to purely ischemic or hemorrhagic strokes. Cumulative focal brain damage, determined by neuroimaging after the first 2 weeks, is the strongest known predictor of patient outcome half a year after the initial hemorrhage. Because of the unique ability to implant neuromonitoring probes at the brain surface before stroke onset and to perform longitudinal MRI scans before and after stroke, delayed cerebral ischemia is currently the stroke variant in humans whose pathophysiological details are by far the best characterized. Optoelectrodes located directly over newly developing delayed infarcts have shown that, as mechanistic correlates of infarct development, spreading depolarizations trigger (1) spreading ischemia, (2) severe hypoxia, (3) persistent activity depression, and (4) transition from clustered spreading depolarizations to a negative ultraslow potential. Furthermore, traumatic brain injury and subarachnoid hemorrhage are the second and third most common etiologies of brain death during continued systemic circulation. Here, we use examples to illustrate that although the pathophysiological cascades associated with brain death are global, they closely resemble the local cascades associated with the development of delayed cerebral infarcts.

Risk factors and predictive markers of post-stroke cognitive decline-A mini review

Stroke is one of the top causes of death and disability worldwide. Cognitive impairments are found in more than 70% of individuals who have survived a stroke. Cognitive decline is a major contributor to disability, dependency, and morbidity. The prevalence and severity of dementia vary depending on different characteristics of the stroke and other clinical risk factors. Here we discuss the effects of stroke territory, patients' age, sex, cerebral blood flow, acute reperfusion therapy, and cognitive reserve of post-stroke cognitive decline. Potential predictive molecular and genetic biomarkers of post-stroke cognitive impairments are also discussed.

Large regional variation in cardiac closure procedures to prevent ischemic stroke in Switzerland a population-based small area analysis

BACKGROUND

Percutaneous closure of a patent foramen ovale (PFO) or the left atrial appendage (LAA) are controversial procedures to prevent stroke but often used in clinical practice. We assessed the regional variation of these interventions and explored potential determinants of such a variation.

METHODS

We conducted a population-based analysis using patient discharge data from all Swiss hospitals from 2013-2018. We derived hospital service areas (HSAs) using patient flows for PFO and LAA closure. We calculated age-standardized mean procedure rates and variation indices (extremal quotient [EQ] and systematic component of variation [SCV]). SCV values >5.4 indicate a high and >10 a very high variation. Because the evidence on the efficacy of PFO closure may differ in patients aged <60 years and ≥60 years, age-stratified analyses were performed. We assessed the influence of potential determinants of variation using multilevel regression models with incremental adjustment for demographics, cultural/socioeconomic, health, and supply factors.

RESULTS

Overall, 2574 PFO and 2081 LAA closures from 10 HSAs were analyzed. The fully adjusted PFO and LAA closure rates varied from 3 to 8 and from 1 to 9 procedures per 100,000 persons per year across HSAs, respectively. The regional variation was high with respect to overall PFO closures (EQ 3.0, SCV 8.3) and very high in patients aged ≥60 years (EQ 4.0, SCV 12.3). The variation in LAA closures was very high (EQ 16.2, SCV 32.1). In multivariate analysis, women had a 28% lower PFO and a 59% lower LAA closure rate than men. French/Italian language areas had a 63% lower LAA closure rate than Swiss German speaking regions and areas with a higher proportion of privately insured patients had a 86% higher LAA closure rate. After full adjustment, 44.2% of the variance in PFO closure and 30.3% in LAA closure remained unexplained.

CONCLUSIONS

We found a high to very high regional variation in PFO closure and LAA closure rates within Switzerland. Several factors, including sex, language area, and insurance status, were associated with procedure rates. Overall, 30-45% of the regional procedure variation remained unexplained and most probably represents differing physician practices.

Extracts from Dendropanax morbifera leaves ameliorates cerebral ischemia-induced hippocampal damage by reducing oxidative damage in gerbil

AIM

In this study, we investigated the effects of Dendropanax morbifera extract (DME) on neuroprotection against ischemic damage in gerbils.

METHODS

DME (100 or 300 mg/kg) was orally administered to gerbils for three weeks, and 2 h after the last DME treatment, transient forebrain ischemia in the common carotid arteries was induced for 5 min. The forebrain ischemia-related cognitive impairments were assessed by spontaneous motor activity and passive avoidance test one and four days after ischemia, respectively. In addition, surviving and degenerating neurons were morphologically confirmed by neuronal nuclei immunohistochemical staining and Fluoro-Jade C staining, respectively, four days after ischemia. Changes of glial morphology were visualized by immunohistochemical staining for each marker such as glial fibrillary acidic protein and ionized calcium-binding protein. Oxidative stress was determined by measurements of dihydroethidium, O2· (formation of formazan) and malondialdehyde two days after ischemia. In addition, glutathione redox system such as reduced glutathione, oxidized glutathione levels, glutathione peroxidase, and glutathione reductase activities were measured two days after ischemia.

RESULTS

Spontaneous motor activity monitoring and passive avoidance tests showed that treatment with 300 mg/kg DME, but not 100 mg/kg, significantly alleviated ischemia-induced memory impairments. In addition, approximately 67 % of mature neurons survived and 29.3 % neurons were degenerated in hippocampal CA1 region four days after ischemia, and ischemia-induced morphological changes in astrocytes and microglia were decreased in the CA1 region after 300 mg/kg DME treatment. Furthermore, treatment with 300 mg/kg DME significantly ameliorated ischemia-induced oxidative stress, such as superoxide formation and lipid peroxidation, two days after ischemia. In addition, ischemia-induced reduction of the glutathione redox system in the hippocampus, assessed two days after the ischemia, was ameliorated by treatment with 300 mg/kg DME. These suggest that DME can potentially reduce ischemia-induced neuronal damage through its antioxidant properties.

Astrocyte Regulation of Neuronal Function and Survival in Stroke Pathophysiology

The interactions between astrocytes and neurons in the context of stroke play crucial roles in the disease's progression and eventual outcomes. After a stroke, astrocytes undergo significant changes in their morphology, molecular profile, and function, together termed reactive astrogliosis. Many of these changes modulate how astrocytes relate to neurons, inducing mechanisms both beneficial and detrimental to stroke recovery. For example, excessive glutamate release and astrocytic malfunction contribute to excitotoxicity in stroke, eventually causing neuronal death. Astrocytes also provide essential metabolic support and neurotrophic signals to neurons after stroke, ensuring homeostatic stability and promoting neuronal survival. Furthermore, several astrocyte-secreted molecules regulate synaptic plasticity in response to stroke, allowing for the rewiring of neural circuits to compensate for damaged areas. In this chapter, we highlight the current understanding of the interactions between astrocytes and neurons in response to stroke, explaining the varied mechanisms contributing to injury progression and the potential implications for future therapeutic interventions.

Sex-Specific Acute Cerebrovascular Responses to Photothrombotic Stroke in Mice

Mechanisms underlying cerebrovascular stroke outcomes are poorly understood, and the effects of biological sex on cerebrovascular regulation post-stroke have yet to be fully comprehended. Here, we explore the overlapping roles of gonadal sex hormones and rho-kinase (ROCK), two important modulators of cerebrovascular tone, on the acute cerebrovascular response to photothrombotic (PT) focal ischemia in mice. Male mice were gonadectomized and female mice were ovariectomized to remove gonadal hormones, whereas control ("intact") animals received a sham surgery prior to stroke induction. Intact wild-type (WT) males showed a delayed drop in cerebral blood flow (CBF) compared with intact WT females, whereby maximal CBF drop was observed 48 h following stroke. Gonadectomy in males did not alter this response. However, ovariectomy in WT females produced a "male-like" phenotype. Intact Rock2+/- males also showed the same phenotypic response, which was not altered by gonadectomy. Alternatively, intact Rock2+/- females showed a significant difference in CBF values compared with intact WT females, displaying higher CBF values immediately post-stroke and showing a maximal CBF drop 48 h post-stroke. This pattern was not altered by ovariectomy. Altogether, these data illustrate sex differences in acute CBF responses to PT stroke, which seem to involve gonadal female sex hormones and ROCK2. Overall, this study provides a framework for exploring sex differences in acute CBF responses to focal ischemic stroke in mice.