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Importance: It is estimated that only 27% of patients with acute ischemic stroke and large vessel occlusion who undergo successful reperfusion after mechanical thrombectomy are disability free at 90 days. An incomplete microcirculatory reperfusion might contribute to these suboptimal clinical benefits. Objective: To investigate whether treatment with adjunct intra-arterial alteplase after thrombectomy improves outcomes following reperfusion. Design, Setting, and Participants: Phase 2b randomized, double-blind, placebo-controlled trial performed from December 2018 through May 2021 in 7 stroke centers in Catalonia, Spain. The study included 121 patients with large vessel occlusion acute ischemic stroke treated with thrombectomy within 24 hours after stroke onset and with an expanded Treatment in Cerebral Ischemia angiographic score of 2b50 to 3. Interventions: Participants were randomized to receive intra-arterial alteplase (0.225 mg/kg; maximum dose, 22.5 mg) infused over 15 to 30 minutes (n = 61) or placebo (n = 52). Main Outcomes and Measures: The primary outcome was the difference in proportion of patients achieving a score of 0 or 1 on the 90-day modified Rankin Scale (range, 0 [no symptoms] to 6 [death]) in all patients treated as randomized. Safety outcomes included rate of symptomatic intracranial hemorrhage and death. Results: The study was terminated early for inability to maintain placebo availability and enrollment rate because of the COVID-19 pandemic. Of 1825 patients with acute ischemic stroke treated with thrombectomy at the 7 study sites, 748 (41%) patients fulfilled the angiographic criteria, 121 (7%) patients were randomized (mean age, 70.6 [SD, 13.7] years; 57 women [47%]), and 113 (6%) were treated as randomized. The proportion of participants with a modified Rankin Scale score of 0 or 1 at 90 days was 59.0% (36/61) with alteplase and 40.4% (21/52) with placebo (adjusted risk difference, 18.4%; 95% CI, 0.3%-36.4%; P = .047). The proportion of patients with symptomatic intracranial hemorrhage within 24 hours was 0% with alteplase and 3.8% with placebo (risk difference, -3.8%; 95% CI, -13.2% to 2.5%). Ninety-day mortality was 8% with alteplase and 15% with placebo (risk difference, -7.2%; 95% CI, -19.2% to 4.8%). Conclusions and Relevance: Among patients with large vessel occlusion acute ischemic stroke and successful reperfusion following thrombectomy, the use of adjunct intra-arterial alteplase compared with placebo resulted in a greater likelihood of excellent neurological outcome at 90 days. However, because of study limitations, these findings should be interpreted as preliminary and require replication. Trial Registration: ClinicalTrials.gov Identifier: NCT03876119; EudraCT Number: 2018-002195-40.
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Artérias Cerebrais , Fibrinolíticos/administração & dosagem , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Trombectomia , Ativador de Plasminogênio Tecidual/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Arteriopatias Oclusivas/complicações , Terapia Combinada , Método Duplo-Cego , Feminino , Humanos , AVC Isquêmico/complicações , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: Embolic strokes of undetermined source represent 20% of ischemic strokes and are associated with a high rate of recurrence. Anticoagulant treatment with rivaroxaban, an oral factor Xa inhibitor, may result in a lower risk of recurrent stroke than aspirin. METHODS: We compared the efficacy and safety of rivaroxaban (at a daily dose of 15 mg) with aspirin (at a daily dose of 100 mg) for the prevention of recurrent stroke in patients with recent ischemic stroke that was presumed to be from cerebral embolism but without arterial stenosis, lacune, or an identified cardioembolic source. The primary efficacy outcome was the first recurrence of ischemic or hemorrhagic stroke or systemic embolism in a time-to-event analysis; the primary safety outcome was the rate of major bleeding. RESULTS: A total of 7213 participants were enrolled at 459 sites; 3609 patients were randomly assigned to receive rivaroxaban and 3604 to receive aspirin. Patients had been followed for a median of 11 months when the trial was terminated early because of a lack of benefit with regard to stroke risk and because of bleeding associated with rivaroxaban. The primary efficacy outcome occurred in 172 patients in the rivaroxaban group (annualized rate, 5.1%) and in 160 in the aspirin group (annualized rate, 4.8%) (hazard ratio, 1.07; 95% confidence interval [CI], 0.87 to 1.33; P=0.52). Recurrent ischemic stroke occurred in 158 patients in the rivaroxaban group (annualized rate, 4.7%) and in 156 in the aspirin group (annualized rate, 4.7%). Major bleeding occurred in 62 patients in the rivaroxaban group (annualized rate, 1.8%) and in 23 in the aspirin group (annualized rate, 0.7%) (hazard ratio, 2.72; 95% CI, 1.68 to 4.39; P<0.001). CONCLUSIONS: Rivaroxaban was not superior to aspirin with regard to the prevention of recurrent stroke after an initial embolic stroke of undetermined source and was associated with a higher risk of bleeding. (Funded by Bayer and Janssen Research and Development; NAVIGATE ESUS ClinicalTrials.gov number, NCT02313909 .).
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Aspirina/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Embolia Intracraniana/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Rivaroxabana/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Idoso , Aspirina/efeitos adversos , Isquemia Encefálica/prevenção & controle , Inibidores do Fator Xa/efeitos adversos , Feminino , Hemorragia/induzido quimicamente , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Rivaroxabana/efeitos adversos , Prevenção Secundária/métodos , Acidente Vascular Cerebral/etiologiaRESUMO
Permutation Entropy (PE) is a powerful tool for measuring the amount of information contained within a time series. However, this technique is rarely applied directly on raw signals. Instead, a preprocessing step, such as linear filtering, is applied in order to remove noise or to isolate specific frequency bands. In the current work, we aimed at outlining the effect of linear filter preprocessing in the final PE values. By means of the Wiener-Khinchin theorem, we theoretically characterize the linear filter's intrinsic PE and separated its contribution from the signal's ordinal information. We tested these results by means of simulated signals, subject to a variety of linear filters such as the moving average, Butterworth, and Chebyshev type I. The PE results from simulations closely resembled our predicted results for all tested filters, which validated our theoretical propositions. More importantly, when we applied linear filters to signals with inner correlations, we were able to theoretically decouple the signal-specific contribution from that induced by the linear filter. Therefore, by providing a proper framework of PE linear filter characterization, we improved the PE interpretation by identifying possible artifact information introduced by the preprocessing steps.
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Surface electromyography (sEMG) is a valuable technique that helps provide functional and structural information about the electric activity of muscles. As sEMG measures output of complex living systems characterized by multiscale and nonlinear behaviors, Multiscale Permutation Entropy (MPE) is a suitable tool for capturing useful information from the ordinal patterns of sEMG time series. In a previous work, a theoretical comparison in terms of bias and variance of two MPE variants-namely, the refined composite MPE (rcMPE) and the refined composite downsampling (rcDPE), was addressed. In the current paper, we assess the superiority of rcDPE over MPE and rcMPE, when applied to real sEMG signals. Moreover, we demonstrate the capacity of rcDPE in quantifying fatigue levels by using sEMG data recorded during a fatiguing exercise. The processing of four consecutive temporal segments, during biceps brachii exercise maintained at 70% of maximal voluntary contraction until exhaustion, shows that the 10th-scale of rcDPE was capable of better differentiation of the fatigue segments. This scale actually brings the raw sEMG data, initially sampled at 10 kHz, to the specific 0-500 Hz sEMG spectral band of interest, which finally reveals the inner complexity of the data. This study promotes good practices in the use of MPE complexity measures on real data.
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Multiscale Permutation Entropy (MPE) analysis is a powerful ordinal tool in the measurement of information content of time series. MPE refinements, such as Composite MPE (cMPE) and Refined Composite MPE (rcMPE), greatly increase the precision of the entropy estimation by modifying the original method. Nonetheless, these techniques have only been proposed as algorithms, and are yet to be described from the theoretical perspective. Therefore, the purpose of this article is two-fold. First, we develop the statistical theory behind cMPE and rcMPE. Second, we propose an alternative method, Refined Composite Downsampling Permutation Entropy (rcDPE) to further increase the entropy estimation's precision. Although cMPE and rcMPE outperform MPE when applied on uncorrelated noise, the results are higher than our predictions due to inherent redundancies found in the composite algorithms. The rcDPE method, on the other hand, not only conforms to our theoretical predictions, but also greatly improves over the other methods, showing the smallest bias and variance. By using MPE, rcMPE and rcDPE to classify faults in bearing vibration signals, rcDPE outperforms the multiscaling methods, enhancing the difference between faulty and non-faulty signals, provided we apply a proper anti-aliasing low-pass filter at each time scale.
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BACKGROUND: In-hospital stroke death rate is an important sanitary issue. Despite advances in the acute phase management of stroke patients, mortality and disability rates remain high. In aging populations and with different mortality between the sexes in general, the study of sex- and age-related differences becomes increasingly relevant for optimization of post-acute clinical care of stroke patients. METHODS: We designed a cohort follow-up study with 13,932 consecutive ischemic stroke (IS) patients from 19 Spanish hospitals. Data was obtained from the Spanish Stroke Registry; transient ischemic attacks and ages <18 years were excluded. Patients were organised by age group and sex. We compared female and male patient cohorts within and across age groups univariately and used multivariable logistic regression to adjust for confounders in differential in-hospital mortality. RESULTS: The median (percentiles 2.5 and 97.5%) age was 78 (41-92) years old for women and 71 (41-92) for men. IS women were more likely to be older, to exhibit cardio-embolic aetiology, and less likely to have been admitted to a stroke unit or to have had a stroke code activated. Both pre-stroke modified Rankin Scale and National Institute of Health Stroke Scale (NIHSS) scores at admission increased significantly with age and were higher in women than those in men. Differences in distributions of common risk factors for IS and of in-hospital outcomes between women and men actually changed with patient's age. It is to be noted here that although there were no statistically significant differences (p > 0.05) between the sexes within any age group, in-hospital mortality appeared significantly higher in women than that in men when analysed overall, due to confounding. Death was more closely related to stroke in women than in men and occurred earlier. Although there were some age-specific sex differences between the predictors for in-hospital mortality, stroke severity measured by NIHSS was the main predictor of in-hospital mortality for both sexes. Topographic classifications - partial anterior circulatory infarct and total anterior circulatory infarct - were significant prognostic factors for men aged <60 years and for those in the 60-69 years range respectively. CONCLUSION: Although most of our findings were consistent with previous studies, it is important to take into account and highlight differences in in-hospital mortality between the sex and age group. Not to account for age-related differences between the sexes can give false results that may mislead management decisions. As most deaths in women were related to stroke, it is important to improve their early management, stroke code activation, access to stroke units and/or revascularisation therapies, especially in the older age groups.
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Mortalidade Hospitalar , Acidente Vascular Cerebral/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores Sexuais , Espanha/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Fatores de Tempo , Adulto JovemRESUMO
Permutation Entropy (PE) and Multiscale Permutation Entropy (MPE) have been extensively used in the analysis of time series searching for regularities. Although PE has been explored and characterized, there is still a lack of theoretical background regarding MPE. Therefore, we expand the available MPE theory by developing an explicit expression for the estimator's variance as a function of time scale and ordinal pattern distribution. We derived the MPE Cramér-Rao Lower Bound (CRLB) to test the efficiency of our theoretical result. We also tested our formulation against MPE variance measurements from simulated surrogate signals. We found the MPE variance symmetric around the point of equally probable patterns, showing clear maxima and minima. This implies that the MPE variance is directly linked to the MPE measurement itself, and there is a region where the variance is maximum. This effect arises directly from the pattern distribution, and it is unrelated to the time scale or the signal length. The MPE variance also increases linearly with time scale, except when the MPE measurement is close to its maximum, where the variance presents quadratic growth. The expression approaches the CRLB asymptotically, with fast convergence. The theoretical variance is close to the results from simulations, and appears consistently below the actual measurements. By knowing the MPE variance, it is possible to have a clear precision criterion for statistical comparison in real-life applications.
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BACKGROUND: The contribution of traditional vascular risk factors to cognitive impairment and dementia is well known. However, in order to obtain possible targets for prevention of vascular cognitive impairment (VCI), it may be important to identify other early and noninvasive markers in asymptomatic middle-aged adults. The calculation of middle cerebral artery-pulsatility index (MCA-PI) is an ultrasonologic, noninvasive, validated and easily reproducible technique to assess increased distal resistance to blood flow. This study aims to assess the relationship between MCA-PI, microstructural white matter (WM) integrity and cognition in a middle-aged asymptomatic population. METHODS: Ninety-five participants from the Barcelona-Asymptomatic Intracranial Atherosclerosis (AsIA) neuropsychology study were included. Subjects were 50-65 years old, free from dementia and without history of vascular disease. Transcranial color-coded duplex ultrasound examination was performed to assess MCA-PI as a measure of vascular resistance. WM integrity was evaluated by fractional anisotropy (FA) measurements of diffusion tensor images (DTI) acquired on a 3T-MRI. The neuropsychological battery was specifically selected to be sensitive to VCI, and included tests that were grouped into six cognitive domains: executive functioning, attention, verbal fluency, memory, visuospatial skills and psychomotor speed. A multivariate linear regression model adjusted for age, gender, years of education, diabetes and hypertension was performed. RESULTS: MCA-PI was significantly associated with WM disintegration in different tracts (fornix, corticospinal and anterior thalamic), all p < 0.05 uncorrected. Both mean MCA-PI and mean FA of those significant tracts were independently associated with poor performance in attention, psychomotor speed, and visuospatial skills after adjustment for age, gender, years of education, and vascular risk factors (all p < 0.05). MCA-PI was independently associated with lower scores in all cognitive domains, except for visuospatial skills. CONCLUSIONS: Our data suggest that MCA-PI may be related to WM disintegration and early vascular cognitive impairment in middle-aged subjects. Although further prospective studies are needed to provide evidence for its validity in longitudinal studies, our results support the proposal of including MCA-PI as part of clinical assessment in order to identify targets for VCI prevention.
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Transtornos Cognitivos/fisiopatologia , Cognição/fisiologia , Imagem de Tensor de Difusão , Memória/fisiologia , Resistência Vascular/fisiologia , Idoso , Envelhecimento/fisiologia , Imagem de Tensor de Difusão/métodos , Função Executiva/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos ProspectivosRESUMO
BACKGROUND: Although multiple studies and meta-analyses have consistently suggested that regular physical activity (PhA) is associated with a decreased stroke risk and recurrence, there is limited data on the possible preconditioning effect of prestroke PhA on stroke severity and prognosis. We aimed to study the association of prestroke PhA with different outcome variables in patients with acute ischemic stroke due to an anterior large vessel occlusion. METHODS: The Prestroke Physical Activity and Functional Recovery in Patients with Ischemic Stroke and Arterial Occlusion trial is an observational and longitudinal study that included consecutive patients with acute ischemic stroke admitted to a single tertiary stroke center. Main inclusion criteria were: anterior circulation ischemic stroke within 12 h from symptom onset; presence of a confirmed anterior large vessel occlusion, and functional independence previous to stroke. Prestroke PhA was evaluated with the International Physical Activity Questionnaire and categorized into mild, moderate and high levels by means of metabolic equivalent (MET) minutes per week thresholds. The primary outcome measure was good functional outcome at 3 months (modified Rankin scale ≤2). Secondary outcomes were severity of stroke at admission, complete early recanalization, early dramatic neurological improvement and final infarct volume. RESULTS: During the study period, 159 patients fulfilled the above criteria. The mean age was 68 years, 62% were men and the baseline NIHSS score was 17. Patients with high levels of prestroke PhA were younger, had more frequently distal occlusions and had lower levels of blood glucose and fibrinogen at admission. After multivariate analysis, a high level of prestroke PhA was associated with a good functional outcome at 3 months. Regarding secondary outcome variables and after adjustment for relevant factors, a high level of prestroke PhA was independently associated with milder stroke severity at admission, early dramatic improvement, early arterial recanalization after intravenous thrombolysis and lower final infarct volume. The beneficial association of prestroke PhA with stroke outcomes was already present with a cutoff point of 1,000 MET min/week, a level of PhA easily achieved by walking 1 h/day during 5 days or by doing a vigorous aerobic activity 1 h/day twice a week. CONCLUSIONS: Prestroke PhA is independently associated with favorable stroke outcomes after a large vessel occlusion. Future research on the underlying mechanisms is needed to understand this neuroprotective effect of PhA.
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Arteriopatias Oclusivas/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Atividade Motora , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Terapia Trombolítica/métodosRESUMO
BACKGROUND: Among the acute ischemic stroke patients with large vessel occlusions and contraindications for the use of IV thrombolysis, mainly on oral anticoagulation or presenting too late, primary endovascular therapy is often performed as an alternative to the standard therapy even though evidence supporting the use of endovascular reperfusion therapies is not yet established. Using different statistical approaches, we compared the functional independence rates at 3 months among patients undergoing primary endovascular therapy and patients treated only with IV thrombolysis. METHODS: We used data from a prospective, government-mandated and externally audited registry of reperfusion therapies for ischemic stroke (January 2011 to November 2012). Patients were selected if treated with either IV thrombolysis alone (n = 1,582) or primary endovascular thrombectomy (n = 250). A series of exclusions were made to homogenize the clinical characteristics among the two groups. We then carried out multivariate logistic regression and propensity score matching analyses on the final study sample (n = 1,179) to compare functional independence at 3 months, as measured by the modified Rankin scale scores 0-2, between the two groups. RESULTS: The unadjusted likelihood of good outcome was poorer among the endovascular group (OR: 0.69; 95% CI: 0.47-1.0). After adjustment, no differences by treatment modality were seen (OR: 1.51; 95% CI: 0.93-2.43 for primary endovascular therapy). Patients undergoing endovascular thrombectomy within 180-270 min (OR: 2.89; 95% CI: 1.17-7.15) and patients with severe strokes (OR: 1.84; 95% CI: 1.02-3.35) did better than their intravenous thrombolysis counterparts. The propensity score-matched analyses with and without adjustment by additional covariates showed that endovascular thrombectomy was as effective as intravenous thrombolysis alone in achieving functional independence (OR for unadjusted propensity score matched: 1.35; 95% CI: 0.9-2.02, OR for adjusted propensity score matched: 1.45; 95% CI: 0.91-2.32). CONCLUSION: This comparative effectiveness study shows that in ischemic stroke patients with contraindications for IV thrombolysis, primary endovascular treatment might be an alternative therapy at least as effective as IV thrombolysis alone. Randomized controlled trials are urgently needed.
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Procedimentos Endovasculares , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/tratamento farmacológico , Procedimentos Endovasculares/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Clinical-Diffusion mismatch (CDM; NIHSS score ≥8 & DWI lesion volume ≤25 mL) and Perfusion-Diffusion mismatch (PDM; difference >20% between initial DWI and MTT lesion volumes) have been proposed as surrogates for ischemic brains that are at risk of infarction. However, their utility to improve the selection of patients for thrombolytic treatment remains controversial. Our aim was to identify molecular biomarkers that can be used with neuroimaging to facilitate the selection of ischemic stroke patients for systemic thrombolysis. METHODS: We prospectively studied 595 patients with ischemic stroke within 12 h of the stroke onset. A total of 184 patients received thrombolytic treatment according to the SITS-MOST criteria. DWI and MTT volumes were measured at admission. The main outcome variable was good functional outcome at 3 months (modified Rankin scale <3). Serum levels of glutamate (Glu), IL-10, TNF-α, IL-6, NSE, and active MMP-9 also were determined at admission. RESULTS: Patients treated with t-PA who presented with PDM had higher IL-10 levels at admission (p < 0.0001). In contrast, patients with CDM had higher levels of IL-10 (p < 0.0001) as well as Glu and TNF-α (all p < 0.05) and lower levels of NSE and active MMP-9 (all p < 0.0001). IL-10 ≥ 30 pg/mL predicts good functional outcome at 3 months with a specificity of 88% and a sensitibity of 86%. IL-10 levels ≥30 pg/mL independently in both patients with PDM (OR, 18.9) and CDM (OR, 7.5), after an adjustment for covariates. CONCLUSIONS: Serum levels of IL-10 facilitate the selection of ischemic stroke patients with CDM and PDM for systemic thrombolysis.
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Isquemia Encefálica , Imagem de Difusão por Ressonância Magnética/métodos , Fibrinolíticos/uso terapêutico , Interleucina-10/sangue , Angiografia por Ressonância Magnética/métodos , Acidente Vascular Cerebral , Terapia Trombolítica/normas , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Isquemia Encefálica/sangue , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Terapia Trombolítica/métodosRESUMO
BACKGROUND AND PURPOSE: Hospitalization as a result of stroke provides an opportunity to stop smoking that is often not taken up. The present study analyzes sociodemographic, psychological, and lesion-related variables to identify associated factors for smoking cessation during the first year after stroke. METHODS: We conducted a prospective longitudinal study with a 1-year follow-up of a cohort of 110 patients with acute stroke who were smokers at the time of diagnosis and were admitted consecutively between January 2005 and July 2007. RESULTS: On hospital release, 69.1% had given up smoking but at 1 year, only 40% had stopped smoking. Of the 110 patients, 27 (24.5%) had an acute stroke lesion in the insular cortex, of which 19 (70.3%) were nonsmokers at 1 year. Strongly associated factors in giving up smoking were the location of the lesion in the insular cortex (OR, 5.42; 95% CI, 1.95-15.01; P=0.001) and having the intention of giving up before the stroke, comparing precontemplating patients (without intention of giving up in the near future) with contemplating and prepared patients (intention of stopping in the near future; OR, 7.29; 95% CI, 1.89-28.07; P=0.004). CONCLUSIONS: Of patients with stroke who were smokers, only 4 of 10 patients had stopped smoking 1 year after admission. Our results show that the variables best predicting smoking cessation in patients with a stroke diagnosis 1 year after hospital discharge are insular damage and the prestroke intention to stop.
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Córtex Cerebral/patologia , Abandono do Hábito de Fumar , Fumar/patologia , Acidente Vascular Cerebral/patologia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND AND PURPOSE: Intracranial atherosclerotic disease (ICAD) remains a challenge for stroke primary and secondary prevention. Molecular pathways involved in the development of ICAD from its asymptomatic stages are largely unknown. In our population-based study, we aimed to compare the risk factor and biomarker profiles associated with intracranial and extracranial asymptomatic cerebral atherosclerosis. METHODS: The Asymptomatic Intracranial Atherosclerosis (AsIA) study cohort includes a random sample population of 933 white subjects >50 years with a moderate to high vascular risk (based on REGICOR score) and without a history of stroke (64% males; mean age, 66 years). Carotid and intracranial atherosclerosis were screened by cervical and transcranial color-coded Duplex ultrasound, being moderate to severe stenoses confirmed by MR angiography. We registered clinical and anthropometric data and created a biobank with blood samples at baseline. A panel of biomarkers involved in atherothrombogenesis was determined: C-reactive protein, asymmetric-dimethylarginine, resistin, and plasminogen activator inhibitor-1. Insulin resistance was quantified by Homeostasis Model Assessment index. RESULTS: After multinomial regression analyses, male sex, hypertension, smoking, and alcoholic habits were independent risk factors of isolated extracranial atherosclerotic disease. Diabetes and metabolic syndrome conferred a higher risk for ICAD than for extracranial atherosclerotic disease. Moreover, metabolic syndrome and insulin resistance were independent risk factors of moderate to severe ICAD but were not risk factors of moderate to severe extracranial atherosclerotic disease. Regarding biomarkers, asymmetric-dimethylarginine was independently associated with isolated ICAD and resistin with combined ICAD-extracranial atherosclerotic disease. CONCLUSIONS: Our findings show distinct clinical and biological profiles in subclinical ICAD and extracranial atherosclerotic disease. Insulin resistance emerged as an important molecular pathway involved in the development of ICAD from its asymptomatic stage.
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Arginina/análogos & derivados , Doenças das Artérias Carótidas/sangue , Complicações do Diabetes/complicações , Arteriosclerose Intracraniana/sangue , Síndrome Metabólica/complicações , Resistina/sangue , Idoso , Arginina/sangue , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doenças das Artérias Carótidas/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Resistência à Insulina/fisiologia , Arteriosclerose Intracraniana/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/sangue , Análise de Regressão , Fatores de Risco , EspanhaRESUMO
BACKGROUND AND PURPOSE: Clinical-diffusion mismatch (CDM; National Institutes of Health Stroke Scale score≥8 and diffusion-weighted imaging lesion volume<25 mL) has been suggested as a surrogate of ischemic brain at risk of infarction and might be used to recognize salvageable ischemic tissue. Our aim was to identify early biomarkers associated with the presence of CDM. METHODS: We prospectively evaluated CDM in 226 patients (71.6±11.1 years, 58% men) with hemispheric ischemic stroke within 12 hours from symptom onset (median, 3.6 hours). Diffusion-weighted MRI lesion volume was measured by manual segmentation method. Serum levels of glutamate, aspartate, interleukin-10, tumor necrosis factor-α, interleukin-6, S100ß, neuron-specific enolase, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, active matrix metalloproteinase-9, and cellular fibronectin were determined by immunoassay or high-performance liquid chromatography techniques in blood samples obtained at admission. RESULTS: CDM was found in 61 patients (26.9%). Patients with CDM had higher serum levels of interleukin-10, tumor necrosis factor-α, and glutamate and lower serum levels of neuron-specific enolase, interleukin-6, and active matrix metalloproteinase-9 (all P<0.0001). Binary logistic regression showed that tumor necrosis factor-α≥21 pg/mL (OR, 21), glutamate≥230 µmol/L (OR, 27), neuron-specific enolase≥23 ng/mL (OR, 0.05), interleukin-6≥10 pg/mL (OR, 0.06), and active matrix metalloproteinase-9≥21 ng/mL (OR, 0.28) were independent molecular predictors of CDM after adjustment for covariates. The association of interleukin-10≥23 pg/mL and glutamate≥230 µmol/L levels predicted CDM with a sensitivity of 96% and a specificity of 98%. CONCLUSIONS: High levels of interleukin-10, tumor necrosis factor-α, and glutamate as well as low levels of neuron-specific enolase, interleukin-6, and active matrix metalloproteinase-9 are associated with CDM.
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Biomarcadores/sangue , Isquemia Encefálica/sangue , Acidente Vascular Cerebral/sangue , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Ácido Glutâmico/sangue , Humanos , Molécula 1 de Adesão Intercelular/sangue , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Metaloproteinase 9 da Matriz/sangue , Pessoa de Meia-Idade , Fosfopiruvato Hidratase/sangue , Estudos Prospectivos , Acidente Vascular Cerebral/patologia , Fator de Necrose Tumoral alfa/sangue , Molécula 1 de Adesão de Célula Vascular/sangueRESUMO
RATIONALE: The potential value of rescue intraarterial thrombolysis in patients with large vessel occlusion stroke treated with mechanical thrombectomy has not been assessed in randomized trials. AIM: The CHemical OptImization of Cerebral Embolectomy trial aims to establish whether rescue intraarterial thrombolysis is more effective than placebo in improving suboptimal reperfusion scores in patients with large vessel occlusion stroke treated with mechanical thrombectomy. SAMPLE SIZE ESTIMATES: A sample size of 200 patients allocated 1:1 to intraarterial thrombolysis or intraarterial placebo will have >95% statistical power for achieving the primary outcome (5% in the control versus 60% in the treatment group) for a two-sided (5% alpha, and 5% lost to follow-up). METHODS AND DESIGN: We conducted a multicenter, randomized, placebo-controlled, double blind, phase 2b trial. Eligible patients are 18 or older with symptomatic large vessel occlusion treated with mechanical thrombectomy resulting in a modified treatment in cerebral ischemia score 2b at end of the procedure. Patients will receive 20-30 min intraarterial infusion of recombinant tissue plasminogen activator or placebo (0.5 mg/ml, maximum dose limit 22.5 mg). STUDY OUTCOME(S): The primary outcome is the proportion of patients with an improved modified treatment in cerebral ischemia score 10 min after the end of the study treatment. Secondary outcomes include the shift analysis of the modified Rankin Scale, the infarct expansion ratio, the proportion of excellent outcome (modified Rankin Scale 0-1), the proportion of infarct expansion, and the infarction volume. Mortality and symptomatic intracerebral bleeding will be assessed. DISCUSSION: The study will provide evidence whether rescue intraarterial thrombolysis improves brain reperfusion in patients with large vessel occlusion stroke and incomplete reperfusion (modified treatment in cerebral ischemia 2b) at the end of mechanical thrombectomy.
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Isquemia Encefálica , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Embolectomia , Fibrinolíticos/uso terapêutico , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do TratamentoRESUMO
Cell death induced by over-activation of glutamate receptors occurs in different neuropathologies. Cholesterol depletors protect from neurotoxic over-activation of glutamate receptors, and we have recently reported that this neuroprotection is associated with a reduction of the N-methyl-D-aspartate subtype of glutamate receptors in detergent-resistant membrane domains (DRM). In the present study we used comparative proteomics to further identify which proteins, besides the N-methyl-D-aspartate receptor, change its percentage of association to DRM after treatment of neurons with simvastatin. We detected 338 spots in neuronal DRM subjected to 2-DE; eleven of these spots changed its intensity after treatment with simvastatin. All 11 differential spots showed reduced intensity in simvastatin-treated samples and were identified as adipocyte plasma membrane associated protein, enolase, calretinin, coronin 1a, f-actin capping protein alpha1, f-actin capping protein alpha2, heat shock cognate protein 71, malate dehydrogenase, n-myc downregulated gene 1, prohibitin 2, Rab GDP dissociation inhibitor, translationally controlled tumor protein and voltage dependent anion selective channel protein 1. The proteins tested colocalized with the lipid raft marker caveolin-1. Interestingly, the proteins we have identified in the present study had been previously reported to play a role in cell fate and, thus, they might represent novel targets for neuroprotection.
Assuntos
Cálcio/metabolismo , Membrana Celular/química , Citoesqueleto/química , Homeostase/efeitos dos fármacos , Proteoma/análise , Sinvastatina/farmacologia , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND AND PURPOSE: We aimed to analyze the frequency of persistent hyperglycemia (PH), its implications for outcome, and to document the inpatient management of hyperglycemia. METHODS: Post hoc analysis of the GLIAS (Glycemia in Acute Stroke) study, a multicenter, prospective, and observational cohort study of 476 acute ischemic stroke patients. Capillary finger-prick glucose was determined on admission and during the first 48 hours. We defined PH was defined as at least 2 values ≥155 mg/dL. Outcome (modified Rankin Scale) was evaluated at 3 months. RESULTS: PH developed in 117 patients (24.7%). PH was associated with poorer outcome (modified Rankin Scale score >2: 56.2% vs 28.1%; P<0.01) and higher mortality (26.7% vs 5.9%; P<0.01) than those with glycemia <155 mg/dL. PH ≥155 mg/dL was associated with a 4-fold increase in the odds of poor outcome at 3 months (odds ratio, 4.7; 95% confidence interval, 2.2-10.2) after adjustment for age, gender, hypertension, diabetes, stroke severity, admission glycemia, and infarct volume. Only 20% of patients with hyperglycemia ≥155 mg/dL received insulin on admission, with a progressive increase in the use of insulin during the following 48 hours. However, 114 (39.1%) out of 291 patients who received corrective treatment for hyperglycemia still had levels ≥155 mg/dL. CONCLUSIONS: PH ≥155 mg/dL is a common observation in acute ischemic stroke patients that is associated with poorer outcome and higher mortality. Almost 40% of patients maintained levels ≥155 mg/dL despite corrective treatment.
Assuntos
Isquemia Encefálica/complicações , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Acidente Vascular Cerebral/complicações , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
BACKGROUND: The free-radical-trapping agent NXY-059 showed promise as a neuroprotectant in the Stroke-Acute Ischemic NXY Treatment I (SAINT I) trial, reducing disability when given to patients who had acute ischemic stroke. We sought confirmation of efficacy in a second, larger trial. METHODS: We enrolled 3306 patients with acute ischemic stroke in a randomized, double-blind trial to receive a 72-hour infusion of intravenous NXY-059 or placebo within 6 hours after the onset of stroke symptoms. Our primary end point was the distribution of disability scores on the modified Rankin scale at 90 days. We examined scores on neurologic and activities-of-daily-living scales as secondary end points. We also tested the hypothesis that NXY-059 would reduce alteplase-related intracranial hemorrhages. RESULTS: The efficacy analysis was based on 3195 patients. Prognostic factors were well balanced between the treatment groups. Mortality was equal in the two groups, and adverse-event rates were similar. The distribution of scores on the modified Rankin scale did not differ between the group treated with NXY-059 (1588 patients) and the placebo group (1607 patients; P=0.33 by the Cochran-Mantel-Haenszel test; odds ratio for limiting disability, 0.94; 95% confidence interval [CI], 0.83 to 1.06). Analysis of categorized scores on the modified Rankin scale confirmed the lack of benefit: the odds ratio for trichotomization into modified Rankin scale scores of 0 to 1 versus 2 to 3 versus 4 to 6 was 0.92 (95% CI, 0.80 to 1.06). There was no evidence of efficacy for any of the secondary end points. Among patients treated with alteplase, there was no difference between the NXY-059 group and the placebo group in the frequency of symptomatic or asymptomatic hemorrhage. CONCLUSIONS: NXY-059 is ineffective for the treatment of acute ischemic stroke within 6 hours after the onset of symptoms. (ClinicalTrials.gov number, NCT00061022 [ClinicalTrials.gov].)
Assuntos
Benzenossulfonatos/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Fármacos Cardiovasculares/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Doença Aguda , Idoso , Benzenossulfonatos/efeitos adversos , Fármacos Cardiovasculares/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Masculino , Razão de Chances , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Falha de TratamentoRESUMO
The main objective of this research work was to study the association of serum levels of growth factors (GF) and SDF-1α with the functional outcome and reduction of lesion volume in ischemic stroke patients. In this multicenter study, 552 patients with non-lacunar stroke (male, 62.1%; mean age, 68.2 ± 11.4) were included within 24 h from symptom onset. The main outcome variable was good functional outcome (modified Rankin Scale [mRS] ≤ 2) at 12 months. Secondary outcome variable was infarct volume (in mL) after 6 ± 3 months. Serum levels of VEGF, Ang-1, G-CSF, BDNF, and SDF-1α were measured by ELISA at admission, 7 ± 1 days, at 3 ± 1 months, and 12 ± 3 months. Except for BDNF, all GF and SDF-1α serum levels showed a peak value at day 7 and remained elevated during the first 3 months (all p < 0.01). High serum levels at day 7 of VEGF (OR, 19.3), Ang-1 (OR, 14.7), G-CSF (OR, 9.6), and SDF-1α (OR, 28.5) were independently associated with good outcome at 12 months (all p < 0.0001). On the other hand, serum levels of VEGF (B, - 21.4), G-CSF (B, - 14.0), Ang-1 (B, - 13.3), and SDF-1α (B, - 44.6) measured at day 7 were independently associated with lesion volume at 6 months (p < 0.01). In summary, high serum levels of VEGF, Ang-1, G-CSF, and SDF-1α at day 7 and 3 months after ischemic stroke are associated with good functional outcome and smaller residual lesion at 1 year of follow-up.
Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/sangue , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , Idoso , Quimiocina CXCL12/sangue , Feminino , Humanos , AVC Isquêmico/patologia , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND AND PURPOSE: Evidence is accumulating regarding the prognostic influence of hyperglycemia in patients with acute ischemic stroke. However, the level associated with poor outcome is unknown. Our objectives were to establish the capillary glucose threshold with the highest predictive accuracy of poor outcome and to evaluate its hypothetical value in influencing functional outcome by adjusting for other well-known prognostic factors in acute stroke. METHODS: The authors conducted a multicenter, prospective, and observational cohort study of 476 patients with ischemic stroke within less than 24 hours from stroke onset. Capillary finger-prick glucose and stroke severity were determined on admission and 3 times a day during the first 48 hours. Poor outcome (modified Rankin Scale >2) was evaluated at 3 months. RESULTS: The receiver operating characteristic curves showed the predictive value of maximum capillary glucose at any time within the first 48 hours with an area under the curve of 0.656 (95% CI, 0.592 to 0.720; P<0.01) and pointed to 155 mg/dL as the optimal cutoff level for poor outcome at 3 months (53% sensitivity; 73% specificity). This point was associated with a 2.7-fold increase (95% CI, 1.42 to 5.24) in the odds of poor outcome after adjustment for age, diabetes, capillary glucose on admission, infarct volume, and baseline stroke severity and with a 3-fold increase in the risk of death at 3 months (hazard ratio, 3.80; 95% CI, 1.79 to 8.10). CONCLUSIONS: Hyperglycemia >or=155 mg/dL at any time within the first 48 hours from stroke onset, and not only the isolated value of admission glycemia, is associated with poor outcome independently of stroke severity, infarct volume, diabetes, or age.