Gut microbiota plays a role in the pathophysiology of ischaemic stroke (IS) through the bidirectional gut-brain axis. Nevertheless, little is known about sex-specific microbiota signatures in IS ...occurrence.
A total of 89 IS patients and 12 healthy controls were enrolled. We studied the taxonomic differences of the gut microbiota between men and women with IS by shotgun metagenomic sequencing. To evaluate the causal effect of several bacteria on IS risk, we performed a two-sample Mendelian randomisation (MR) with inverse-variance weighting (IVW) using genome-wide association analysis (GWAS) summary statistics from two cohorts of 5959 subjects with genetic and microbiota data and 1,296,908 subjects with genetic and IS data, respectively.
α-Diversity analysis measured using Observed Species (p = 0.017), Chao1 (p = 0.009) and Abundance-based Coverage Estimator (p = 0.012) indexes revealed that IS men have a higher species richness compared with IS women. Moreover, we found sex-differences in IS patients in relation to the phylum Fusobacteria, class Fusobacteriia, order Fusobacteriales and family Fusobacteriaceae (all Bonferroni-corrected p < 0.001). MR confirmed that increased Fusobacteriaceae levels in the gut are causally associated with an increased risk of IS (IVW p = 0.02, β = 0.32).
Our study is the first to indicate that there are gut microbiome differences between men and women with IS, identifying high levels of Fusobacteriaceae in women as a specific risk factor for IS. Incorporating sex stratification analysis is important in the design, analysis and interpretation of studies on stroke and the gut microbiota.
Background and purpose
In patients with acute ischaemic stroke (AIS), haemorrhagic transformation (HT) following endovascular treatment (EVT) is associated with poor functional outcome. However, the ...impact of asymptomatic HT, not linked to neurological deterioration in the acute phase, is unknown. We aimed to investigate the impact of asymptomatic PH1 (aPH1) and PH2 (aPH2) subtypes of HT on the functional outcome of patients treated with EVT.
Methods
We conducted a retrospective study of patients with AIS who were consecutively admitted to our comprehensive stroke centre between January 2019 and December 2022, and who underwent EVT. We collected clinical, radiological, and procedural data. HTs were categorized according to the Heidelberg classification. The primary outcome was the shift on the modified Rankin Scale (mRS) at 3 months of follow‐up. We performed bivariate and multivariable ordinal regression analyses to test the association between aPH1/aPH2 and the primary outcome.
Results
We included 314 patients (mean age = 72.5 years SD = 13.6, 171 54.5% women). We detected 54 (17.2%) patients with HT; 23 (7.3%) were classified as PH2 (11 asymptomatic) and 17 (5.4%) as PH1 (16 asymptomatic). The adjusted common odds ratio for aPH2 of worsening 1 point on the 3‐month mRS was 3.32 (95% confidence interval = 1.16–9.57, p = 0.026). No association was observed for aPH1. aPH2 was also independently associated with lower odds of achieving a favourable outcome (mRS = 0–2). Neither aPH1 nor aPH2 was associated with mortality.
Conclusions
In patients with AIS treated with EVT, aPH2 is independently associated with unfavourable functional outcome.
CADASIL is a small vessel disease caused by mutations in NOTCH3 that lead to an odd number of cysteines in the EGF-like repeat domain, causing protein misfolding and aggregation. The main symptoms ...are migraine, psychiatric disturbances, recurrent strokes and dementia, being executive function characteristically impaired. The molecular pathways altered by this receptor aggregation need to be studied further. A genome-wide transcriptome study (four cases paired with three healthy siblings) was carried out, in addition to a qRT-PCR for validation purposes (ten new cases and eight new controls). To study the expression profile by cell type of the significant mRNAs found, we performed an in situ hybridization (ISH) (nine cases and eight controls) and a research in the Single-nuclei Brain RNA-seq expression browser (SNBREB). Pathway analysis enrichment was carried out with Gene Ontology and Reactome. Neuropsychological tests were performed in five of the qRT-PCR cases. The two most significant differentially expressed mRNAs (BANP, p-value = 7.23 × 10
and PDCD6IP, p-value = 8.36 × 10
) were selected for the validation study by qRT-PCR. Additionally, we selected two more mRNAs (CAMK2G, p-value = 4.52 × 10
and E2F4, p-value = 4.77 × 10
) due to their association with ischemic neuronal death. E2F4 showed differential expression in the genome-wide transcriptome study and in the qRT-PCR (p = 1.23 × 10
), and it was upregulated in CADASIL cases. Furthermore, higher E2F4 expression was associated with worse executive function (p = 2.04 × 10
) and attention and information processing speed (IPS) (p = 8.73 × 10
). In situ hibridization showed E2F4 expression in endothelial and vascular smooth vessel cells. In silico studies indicated that E2F4 is also expressed in brain endothelial cells. Among the most significant pathways analyzed, there was an enrichment of vascular development, cell adhesion and vesicular machinery terms and autophagy process. E2F4 is more highly expressed in the skin biopsy of CADASIL patients compared to controls, and its expression is present in endothelial cells and VSMCs. Further studies are needed to understand whether E2F4 could be useful as a biomarker, to monitor the disease or be used as a therapeutic target.
We evaluated whether stroke severity, functional outcome, and mortality are different in patients with ischemic stroke with or without coronavirus disease 2019 (COVID-19) infection.
A prospective, ...observational, multicentre cohort study in Catalonia, Spain. Recruitment was consecutive from mid-March to mid-May 2020. Patients had an acute ischemic stroke within 48 hours and a previous modified Rankin Scale (mRS) score of 0 to 3. We collected demographic data, vascular risk factors, prior mRS score, National Institutes of Health Stroke Scale score, rate of reperfusion therapies, logistics, and metrics. Primary end point was functional outcome at 3 months. Favourable outcome was defined depending on the previous mRS score. Secondary outcome was mortality at 3 months. We performed mRS shift and multivariable analyses.
We evaluated 701 patients (mean age 72.3±13.3 years, 60.5% men) and 91 (13%) had COVID-19 infection. Median baseline National Institutes of Health Stroke Scale score was higher in patients with COVID-19 compared with patients without COVID-19 (8 3-18 versus 6 2-14,
=0.049). Proportion of patients with a favourable functional outcome was 33.7% in the COVID-19 and 47% in the non-COVID-19 group. However, after a multivariable logistic regression analysis, COVID-19 infection did not increase the probability of unfavourable functional outcome. Mortality rate was 39.3% among patients with COVID-19 and 16.1% in the non-COVID-19 group. In the multivariable logistic regression analysis, COVID-19 infection was a risk factor for mortality (hazard ratio, 3.14 95% CI, 2.10-4.71;
<0.001).
Patients with ischemic stroke and COVID-19 infection have more severe strokes and a higher mortality than patients with stroke without COVID-19 infection. However, functional outcome is comparable in both groups.
Few studies have prospectively examined the risk of recurrent stroke associated with patent foramen ovale. We present the results of the Spanish right-to-left shunt (RLSh) multicenter study.
Four ...hundred eighty-six patients with cryptogenic stoke were included at 17 participating hospitals. Patients were examined by contrast transcranial Doppler methods at baseline. The magnitude of RLSh was quantified during the Valsalva maneuver. Transthoracic and/or transesophageal echocardiography, computed tomography scan, or magnetic resonance imaging was performed. Functional outcome and stroke recurrence were evaluated at 3 months and yearly thereafter. The independent relation between RLSh magnitude and stroke recurrence was analyzed by logistic-regression analysis in the whole group and in the younger subgroup (<55 years).
Massive RLSh was detected in 200 patients (41.2%). The mean follow-up was 729+/-411 days. Stroke recurrence was low (5.8%, n=28) and similar in patients with massive RLSh, with nonmassive RLSh, and with no RLSh, in both the younger group (3.4% vs 2.3% vs 4.5%, respectively; P=0.75) and in the whole population (5.0% vs 6.2% vs 6.3%, respectively; P=0.58). Regression analysis found no association between massive RLSh and recurrent stroke in either group (in the whole population, odds ratio=0.94; 95% CI, 0.36 to 2.40; P=0.89; in the younger population, odds ratio=0.93; 95% CI, 0.18 to 4.91; P=0.93). These results were similar when concurrent atrial septal aneurysm and massive RLSh were analyzed and when antithrombotic treatment and concomitant stroke risk factors were included.
These results suggest that neither massive RLSh nor massive RLSh with concurrent atrial septal aneurysm is an independent risk factor for recurrent stroke, in either the general or younger stroke populations.
Atraumatic convexal subarachnoid hemorrhage (cSAH) in elderly patients is a rare entity that has been associated with cerebral amyloid angiopathy (CAA) and intracerebral hematomas (ICH). To ...characterize this entity and to study these associations, 22 patients over 60 with cSAH were included in a multicenter ambispective cohort study. Clinical data, magnetic resonance imaging (MRI) studies, APOE genotyping, and cerebrospinal fluid (CSF) biomarkers were evaluated. Results were compared with data from healthy controls (HC), non-cSAH CAA patients (CAAo), and Alzheimer disease patients. Convexal subarachnoid hemorrhage presented with transient sensory or motor symptoms. At follow-up (median 30.7 months), 5 patients had died, 6 survivors showed functional disability (modified Rankins Scale (mRS) > 2), and 12 cognitive impairment. Four patients had prior ICH and six had an ICH during follow-up. CSF-Aβ40 and Aβ42 levels were lower in cSAH and CAAo compared with HC. Convexal subarachnoid hemorrhage presented an APOE-ε2 overrepresentation and CAAo had an APOE-ε4 overrepresentation. On MRI, all patients fulfilled CAA-modified Boston criteria and 9 showed cortical ischemia in the surrounding cortex or the vicinity of superficial siderosis. The neuropathologic study, available in one patient, showed severe CAA and advanced Alzheimer-type pathology. Convexal subarachnoid hemorrhage in the elderly is associated with cognitive impairment and lobar ICH occurrence. Our findings support the existence of an underlying CAA pathology.
Cerebral amyloid angiopathy (CAA) is characterized by the accumulation of amyloid-β (Aβ) in brain vessels and is a main cause of lobar intracerebral hemorrhage (ICH) in the elderly. CAA is associated ...with magnetic resonance imaging (MRI) markers of small vessel disease (SVD). Since Aβ is also accumulated in Alzheimer's disease (AD) in the brain parenchyma, we aimed to study if several single nucleotide polymorphisms (SNPs) previously associated with AD were also associated with CAA pathology. Furthermore, we also studied the influence of APOE and CLU genetic variants in apolipoprotein E (ApoE) and clusterin/apolipoprotein J (ApoJ) circulating levels and their distribution among lipoproteins.
The study was carried out in a multicentric cohort of 126 patients with lobar ICH and clinical suspicion of CAA.
We observed several SNPs associated with CAA neuroimaging MRI markers cortical superficial siderosis (cSS), enlarged perivascular spaces in the centrum semiovale (CSO-EPVS), lobar cerebral microbleeds (CMB), white matter hyperintensities (WMH), corticosubcortical atrophy and CAA-SVD burden score. Concretely, ABCA7 (rs3764650), CLU (rs9331896 and rs933188), EPHA1 (rs11767557), and TREML2 (rs3747742) were significantly associated with a CAA-SVD burden score. Regarding circulating levels of apolipoproteins, protective AD SNPs of CLU rs11136000 (T) and rs9331896 (C) were significantly associated with higher HDL ApoJ content in the lobar ICH cohort. APOEε2 carriers presented higher plasma and LDL-associated ApoE levels whereas APOEε4 carriers presented lower plasma ApoE levels. Additionally, we observed that lower circulating ApoJ and ApoE levels were significantly associated with CAA-related MRI markers. More specifically, lower LDL-associated ApoJ and plasma and HDL-associated ApoE levels were significantly associated with CSO-EPVS, lower ApoJ content in HDL with brain atrophy and lower ApoE content in LDL with the extent of cSS.
This study reinforces the relevance of lipid metabolism in CAA and cerebrovascular functionality. We propose that ApoJ and ApoE distribution among lipoproteins may be associated with pathological features related to CAA with higher ApoE and ApoJ levels in HDL possibly enhancing atheroprotective, antioxidative, and anti-inflammatory responses in cerebral β-amyloidosis.
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