Stroke最新文献

Background: Existing data suggested a rural-urban disparity in thrombolytic utilization for ischemic stroke. Here, we examined the use of guideline-recommended stroke care and outcomes in rural hospitals to identify targets for improvement.

Methods: This retrospective cohort study included patients (aged ≥18 years) treated for acute ischemic stroke at Get With The Guidelines-Stroke hospitals from 2017 to 2019. Multivariable mixed-effect logistic regression was used to compare thrombolysis rates, speed of treatment, secondary stroke prevention metrics, and outcomes after adjusting for patient- and hospital-level characteristics and stroke severity.

Results: Among the 1 127 607 patients admitted to Get With The Guidelines-Stroke hospitals in 2017 to 2019, 692 839 patients met the inclusion criteria. Patients who presented within 4.5 hours were less likely to receive thrombolysis in rural stroke centers compared with urban stroke centers (31.7% versus 43.5%; adjusted odds ratio [aOR], 0.72 [95% CI, 0.68-0.76]) but exceeded rural nonstroke centers (22.1%; aOR, 1.26 [95% CI, 1.15-1.37]). Rural stroke centers were less likely than urban stroke centers to achieve door-to-needle times of ≤45 minutes (33% versus 44.7%; aOR, 0.86 [95% CI, 0.76-0.96]) but more likely than rural nonstroke centers (aOR, 1.24 [95% CI, 1.04-1.49]). For secondary stroke prevention metrics, rural stroke centers were comparable to urban stroke centers but exceeded rural nonstroke centers (aOR of 1.66, 1.94, 2.44, 1.5, and 1.72, for antithrombotics within 48 hours of admission, antithrombotics at discharge, anticoagulation for atrial fibrillation/flutter, statin treatment, and smoking cessation, respectively). In-hospital mortality was similar between rural and urban stroke centers (aOR, 1.11 [95% CI, 0.99-1.24]) or nonstroke centers (aOR, 1.00 [95% CI, 0.84-1.18]).

Conclusions: Rural hospitals had lower thrombolysis utilization and slower treatment times than urban hospitals. Rural stroke centers provided comparable secondary stroke prevention treatment to urban stroke centers and exceeded rural nonstroke centers. These results reveal important opportunities and specific targets for rural health equity interventions.

Background: Functional activation of the focal ischemic brain has been reported to improve outcomes by augmenting collateral blood flow. However, functional activation also increases metabolic demand and might thereby worsen outcomes. Indeed, preclinical and clinical reports have been conflicting. Here, we tested the effect of functional activation during acute ischemic stroke using distal middle cerebral artery occlusion in anesthetized mice.

Methods: Using transgenic mice expressing channelrhodopsin-2 in neurons, we delivered functional activation using physiological levels of transcranial optogenetic stimulation of the moderately ischemic cortex (ie, penumbra), identified using real-time full-field laser speckle perfusion imaging during a 1-hour distal microvascular clip of the middle cerebral artery. Neuronal activation was confirmed using evoked field potentials, and infarct volumes were measured in tissue slices 48 hours later.

Results: Optogenetic stimulation of the penumbra was associated with more than 2-fold larger infarcts than stimulation of the contralateral homotopic region and the sham stimulation group (n=10, 7, and 9; 11.0±5.6 versus 5.1±4.3 versus 4.1±3.7 mm³; P=0.008, 1-way ANOVA). Identical stimulation in wild-type mice that do not express channelrhodopsin-2 did not have an effect. Optogenetic stimulation was associated with a small increase in penumbral perfusion that did not explain enlarged infarcts.

Conclusions: Our data suggest that increased neuronal activity during acute focal arterial occlusions can be detrimental, presumably due to increased metabolic demand, and may have implications for the clinical management of hyperacute stroke patients.

While imaging has traditionally played a fundamental role in the selection of patients undergoing endovascular thrombectomy, recent thrombectomy trials involving patients with large ischemic strokes demonstrated a consistent benefit of endovascular thrombectomy across all imaging strata, suggesting that reperfusion benefit may exist independent of current imaging constructs. Although these findings attest to the uniformly beneficial effects of reperfusion, they also shed doubt on the accuracy and utility of our imaging modalities in defining reversible versus irreversible ischemia and challenge the premise of imaging-based selection. We aimed to review the histopathologic studies and clinical trials that have shaped our understanding of current imaging constructs aiming to outline the existing imaging-neuropathological gap that may be far wider than previously perceived.

Background: Cerebral small vessel disease (cSVD) of ischemic type, either sporadic or genetic, as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), can impact the quality of daily life on various cognitive, motor, emotional, or behavioral aspects. No instrument has been developed to measure these outcomes from the patient's perspective. We thus aimed to develop and validate a patient-reported questionnaire.

Methods: In a development study, 79 items were generated by consensus between patients, family representatives, and cSVD experts. A first sample of patients allowed assessing the feasibility (missing data, floor and ceiling effect, and acceptability), internal consistency, and dimensionality of a first set of items. Thereafter, in a validation study, we tested a reduced version of the item set in a larger sample to assess the feasibility, internal consistency, dimensionality, test-retest reliability, concurrent validity, and sensitivity to change.

Results: The scale was developed in 44 patients with cSVD and validated in a second sample of 89 individuals (including 43 patients with CADASIL and 46 with another cSVD). The final CADASIL Patient-Reported Outcome scale comprised 18 items covering 4 categories of consequences (depression/anxiety, attention/executive functions, motor, and daily activities) of the disease. The proportion of missing data was low, and no item displayed a major floor or ceiling effect. Both the internal consistency and test-retest reliability were good (Cronbach alpha=0.95, intraclass correlation coefficient=0.88). In patients with CADASIL, CADASIL Patient-Reported Outcome scores correlated with the modified Rankin Scale, Starkstein Apathy Scale, Hospital Anxiety and Depression scale, Working Memory Index, and trail making test times. In patients with other cSVDs, CADASIL Patient-Reported Outcome correlated only with Hospital Anxiety and Depression scale and Starkstein Apathy Scale.

Conclusions: The CADASIL Patient-Reported Outcome may be an innovative instrument for measuring patient-reported outcomes in future cSVD trials. Full validation was obtained for its use in patients with CADASIL, but further improvement is needed for its application in other cSVDs.

Background: In ischemia, acidosis occurs in/around injured tissue and parallels disease progression. Therefore, targeting an acid-sensitive receptor offers unique advantages in achieving the spatial and temporal specificity required for therapeutic interventions. We previously demonstrated that increased expression of GPR68 (G protein-coupled receptor 68), a proton-sensitive G protein-coupled receptor, mitigates ischemic brain injury. Here, we investigated the mechanism underlying GPR68-dependent protection.

Methods: We performed biochemical and molecular analyses to examine poststroke signaling. We used in vitro brain slice cultures and in vivo mouse transient middle cerebral artery occlusion (tMCAO) models to investigate ischemia-induced injuries.

Results: GPR68 deletion reduced PERK (protein kinase R-like ER kinase) expression in mouse brain. Compared with the wild-type mice, the GPR68-/- (knockout) mice exhibited a faster decline in eIF2α (eukaryotic initiation factor-2α) phosphorylation after tMCAO. Ogerin, a positive modulator of GPR68, stimulated eIF2α phosphorylation at 3 to 6 hours after tMCAO, primarily in the ipsilateral brain tissue. Consistent with the changes in eIF2α phosphorylation, Ogerin enhanced tMCAO-induced reduction in protein synthesis in ipsilateral brain tissue. In organotypic cortical slices, Ogerin reduced pH 6 and oxygen-glucose deprivation-induced neurotoxicity. Following tMCAO, intravenous delivery of Ogerin reduced brain infarction in wild-type but not knockout mice. Coapplication of a PERK inhibitor abolished Ogerin-induced protection. Delayed Ogerin delivery at 5 hours after tMCAO remained protective, and Ogerin has a similar protective effect in females. Correlated with these findings, tMCAO induced GPR68 expression at 6 hours, and Ogerin alters post-tMCAO proinflammatory/anti-inflammatory cytokine/chemokine expression profile.

Conclusions: These data demonstrate that GPR68 potentiation leads to neuroprotection, at least in part, through enhancing PERK-eIF2α activation in ischemic tissue but has little impact on healthy tissue.

Artificial intelligence (AI) large language models (LLMs) now produce human-like general text and images. LLMs' ability to generate persuasive scientific essays that undergo evaluation under traditional peer review has not been systematically studied. To measure perceptions of quality and the nature of authorship, we conducted a competitive essay contest in 2024 with both human and AI participants. Human authors and 4 distinct LLMs generated essays on controversial topics in stroke care and outcomes research. A panel of Stroke Editorial Board members (mostly vascular neurologists), blinded to author identity and with varying levels of AI expertise, rated the essays for quality, persuasiveness, best in topic, and author type. Among 34 submissions (22 human and 12 LLM) scored by 38 reviewers, human and AI essays received mostly similar ratings, though AI essays were rated higher for composition quality. Author type was accurately identified only 50% of the time, with prior LLM experience associated with improved accuracy. In multivariable analyses adjusted for author attributes and essay quality, only persuasiveness was independently associated with odds of a reviewer assigning AI as author type (adjusted odds ratio, 1.53 [95% CI, 1.09-2.16]; P=0.01). In conclusion, a group of experienced editorial board members struggled to distinguish human versus AI authorship, with a bias against best in topic for essays judged to be AI generated. Scientific journals may benefit from educating reviewers on the types and uses of AI in scientific writing and developing thoughtful policies on the appropriate use of AI in authoring manuscripts.

Background: For several decades, it has been recognized that overactivation of the glutamate-gated N-methyl-D-aspartate receptors (NMDARs) and subsequent Ca²⁺ toxicity play a critical role in ischemic brain injury. 24S-hydroxycholesterol (24S-HC) is a major cholesterol metabolite in the brain, which has been identified as a potent positive allosteric modulator of NMDAR in rat hippocampal neurons. We hypothesize that 24S-HC worsens ischemic brain injury via its potentiation of the NMDAR, and reducing the production of 24S-HC by targeting its synthetic enzyme CYP46A1 provides neuroprotection.

Methods: We tested this hypothesis using electrophysiological, pharmacological, and transgenic approaches and in vitro and in vivo cerebral ischemia models.

Results: Our data show that 24S-HC potentiates NMDAR activation in primary cultured mouse cortical neurons in a concentration-dependent manner. At 10 µmol/L, it dramatically increases the steady-state currents by 51% and slightly increases the peak currents by 20%. Furthermore, 24S-HC increases NMDA and oxygen-glucose deprivation-induced cortical neuronal injury. The increased neuronal injury is largely abolished by NMDAR channel blocker MK-801, suggesting an NMDAR-dependent mechanism. Pharmacological inhibition of CYP46A1 by voriconazole or gene knockout of Cyp46a1 dramatically reduces ischemic brain injury.

Conclusions: These results identify a new mechanism and signaling cascade that critically impacts stroke outcome: CYP46A1 → 24S-HC → NMDAR → ischemic brain injury. They offer proof of principle for further development of new strategies for stroke intervention by targeting CYP46A1 or its metabolite 24S-HC.

Background: Large vessel occlusion acute ischemic stroke prognosis improved following the 2015 endovascular therapy (EVT) trials. Blood-based biomarkers may improve outcome prediction. We aimed to assess plasma brain-derived tau (BD-Tau) performance in predicting post-EVT large vessel occlusion acute ischemic stroke outcomes.

Methods: We included 2 temporally independent prospective cohorts of anterior circulation in patients with large vessel occlusion acute ischemic stroke who successfully recanalized post-EVT. We measured plasma BD-Tau, GFAP (glial-fibrillary-acidic-protein), NfL (neurofilament-light-chain), and total-Tau upon admission, immediately, 24 hours, and 72 hours post-EVT. Twenty-four-hour neuroimaging and 90-day functional outcomes were independently assessed using the Alberta Stroke Program Early Computed Tomography Score (good outcome: >7 or unchanged) and the modified Rankin Scale (favorable outcome <3 or unchanged), respectively. Based on the first cohort (derivation), we built a multivariable logistic regression model to predict a 90-day functional outcome. Model results were evaluated using the second cohort (evaluation).

Results: In the derivation cohort (n=78, mean age=72.9 years, 50% women), 62% of patients had a good 24-hour neuroimaging outcome, and 45% had a favorable 90-day functional outcome. GFAP admission-to-EVT rate-of-change was the best predictor for early neuroimaging outcome but not for 90-day functional outcome. At admission, BD-Tau levels presented the highest discriminative performance for 90-day functional outcomes (area under the curve, 0.76 [95% CI, 0.65-0.87]; P<0.001). The model incorporating age, admission BD-Tau, and 24-hour Alberta Stroke Program Early Computed Tomography Score achieved excellent discrimination of 90-day functional outcome (area under the curve, 0.89 [95% CI, 0.82-0.97]; P<0.001). The score's predictive performance was maintained in the evaluation cohort (n=66; area under the curve, 0.82 [95% CI, 0.71-0.92]; P<0.001).

Conclusions: Admission plasma BD-Tau accurately predicted 90-day functional outcomes in patients with large vessel occlusion acute ischemic stroke after successful EVT. The proposed model may predict functional outcomes using objective measures, minimizing human-related biases and serving as a simplified prognostic tool for AIS.