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1.
Int J Stroke ; 8(8): 652-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22813096

RESUMO

BACKGROUND: Although the established measure of disability post stroke, the modified Rankin Scale emphasizes motor function and may underestimate the importance of cognitive impairment in more disabled patients. A subset of four items from the National Institutes of Health Stroke Scale has been proposed to assess cognitive function after stroke (Cog-4), and to correlate with modified Rankin Scale. Items correspond to orientation, executive function, language, and inattention. We investigated responsiveness of Cog-4 to treatment with thrombolysis and whether it offers information that supplements modified Rankin Scale. METHODS: We included 6268 patients from the Virtual International Stroke Trials Archive: 2734 received intravenous thrombolysis and 3534 were treated conservatively. We compared day 90 outcomes between treated and untreated groups, by modified Rankin Scale (illustrative) and by Cog-4 (primary measure) adjusting for age, baseline National Institutes of Health stroke scale, hemispheric lateralisation as well as baseline Cog-4 and baseline National Institutes of Health Stroke Scale excluding baseline Cog-4 separately. Analysis of Cog-4 was repeated within strata of 90 day modified Rankin Scale. Statistical analyses included proportional odds logistic regression and Cochran-Mantel-Haenszel test. RESULTS: Modified Rankin Scale showed a difference between treatment groups of expected magnitude (odds ratio 1·56; 95% confidence interval 1·43-1·72; P < 0·001). After adjustment for imbalance in baseline prognostic factors, the distribution of Cog-4 scores at 90 days was better in thrombolysed patients compared with nonthrombolysed patients (odds ratio 1·31; 95% confidence interval 1·18-1·47; P = 0·006). However, Cog-4 analysis stratified by 90-day modified Rankin Scale was neutral between treatment groups (OR 1·01; 95% CI 0·90-1·14), and Cog-4 was not responsive to treatment group even within modified Rankin Scale categories 4 and 5 despite substantial cognitive deficits in these patients. CONCLUSION: Although Cog-4 may be responsive to treatment effects, it does not provide additional information beyond modified Rankin Scale assessment.


Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia , Idoso , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica
2.
Eur J Neurol ; 18(2): 306-311, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20629718

RESUMO

BACKGROUND: We aimed at determining the safety and efficacy of IV alteplase in Austrian versus non-Austrian centres as documented in the Internet-based registers Safe Implementation of Thrombolysis for Stroke - MOnitoring STudy (SITS-MOST) and - International Stroke Thrombolysis Register (SITS-ISTR). METHODS: We analysed patient data entered in the registers SITS-MOST and SITS-ISTR in the period December 2002 to 15 November 2007. RESULTS: Compared to the non-Austrian cohort (n=15153), the Austrian cohort (n=896) was slightly older [median, interquartile range (IQR): 70, 60-77 years vs. 69, 60-76 years, P=0.05] and included more women (44.6% vs. 41.0%, P=0.03). Austrian patients had a significantly shorter stroke onset-to-treatment time (OTT; median, IQR: 135, 105-160 min vs. 145, 115-170 min, P<0.0005). Symptomatic intracerebral haemorrhages were observed in 1.6% of Austrian and 1.7% of non-Austrian patients (P=0.82). At 3 months, 50.8% of Austrian and 53.0% of non-Austrian patients were independent (P=0.23), but death was less frequent in Austrian patients (12.1% vs. 14.9%, P=0.03). Multivariate analyses adjusted for demographic and baseline characteristics confirmed lower mortality at 3 months in the Austrian cohort (odds ratio 0.81, 95% confidence intervals 0.71-0.92, P=0.001). Longer OTT was associated with increased mortality at 3 months, with a hazard ratio of 1.02 (95% CI 1.01-1.03; P=0.005) for each 10-min increase in OTT. CONCLUSIONS: The implementation of intravenous alteplase for acute stroke has been safe and efficacious in Austrian centres. OTT and mortality were significantly lower in Austrian patients compared to non-Austrian SITS centres.


Assuntos
Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/estatística & dados numéricos , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Áustria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Resultado do Tratamento
3.
QJM ; 101(11): 863-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18694900

RESUMO

AIM: To describe the United Kingdom (UK) experience with thrombolytic therapy with intravenous alteplase (rt-PA) for stroke, as captured by the Implementation of Thrombolysis in Stroke (SITS) project. METHODS: The multinational Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) was an observational study to assess the safety and efficacy of thrombolytic therapy, when administered within the first 3 h after onset of ischaemic stroke. SITS-MOST was embedded within the Safe Implementation of Thrombolysis in Stroke-International Stroke Thrombolysis Register (SITS-ISTR), an internet-based, international monitoring registry for auditing the safety and efficacy of routine therapeutic use of thrombolysis in acute ischaemic stroke. We performed an analysis of data contributed to SITS-MOST and SITS-ISTR from UK centres. RESULTS: A total of 614 patients received thrombolysis for stroke between December 2002 and April 2006, 327 were registered to SITS-MOST and 287 to SITS-ISTR. Thirty-one centres treated patients in the UK, of which 23 registered patients in both SITS-MOST and SITS-ISTR and eight solely to SITS-ISTR. The median age from the UK SITS-MOST was identical to the non-UK SITS-MOST register: 68 years (IQR 59-75). The majority (96.1%) of patients from the UK were treated between 8.00 a.m. and 9.00 p.m., and only 18.4% were treated on weekend days, reflecting the difficulties of maintaining provision of a thrombolytic service out of hours. Median onset-to-treatment-time was 155 min (IQR 130-170 min) for the UK, compared to 140 min (IQR 114-165 min) for the non-UK SITS-MOST group (P < 0.001). UK SITS-MOST patients at baseline had more severe stroke in comparison with non-UK patients [median NIHSS 14.5 (IQR 9-19) vs. 12 (IQR 8-17) (P < 0.001)]. Forty-eight percent of UK patients achieved mRS of 0-2 (independence), compared to 55% of the non-UK SITS-MOST register. There was no significant difference in symptomatic intracerebral haemorrhage rate in the UK compared with the non-UK SITS-MOST patients [2.5% (95% CI 1.3-4.8) vs. 1.7% (95% CI 1.4-2.0) P = 0.28]. In the multivariate analysis, there was no statistically significant difference in any outcome between UK and non-UK SITS-MOST patients. CONCLUSION: Thrombolytic therapy for stroke has been implemented successfully at a small number of UK stroke centres, with patchy provision throughout the country. The low frequency of treatment out with office hours suggests deficient infrastructure to support delivery. UK patients tended to be more severely affected at baseline and to be treated later. Outcomes are comparable to those seen at the non-UK SITS centres.


Assuntos
Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Reino Unido
4.
Int J Clin Pract ; 61(10): 1749-55, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17877661

RESUMO

BACKGROUND: The primary role of a trial's data monitoring committee (DMC) is to ensure the safety of enrolled patients. In stroke trials, safety is monitored typically by comparing death and stroke-specific events between treatment groups. DMCs may also have the remit for monitoring efficacy depending on the aims of the trial. We hypothesised that functional outcome at the end of follow-up, a measure of efficacy, is also a powerful measure of safety and tested this in a systematic review. METHODS: Acute stroke trials with a negative outcome or which were stopped prematurely on the grounds of safety were sought systematically from searches of electronic databases and published reviews. Information on early and late death, impairment and functional outcome, and the presence of a DMC, were recorded for each trial. The results for each outcome measure were ranked within each trial to determine which was most statistically efficient in detecting hazard. RESULTS: Fourteen trials were included. The most efficient outcomes for detecting hazard were late death or disability, six trials; early death, four trials (two of which tested thrombolysis); late death, three trials and late death or impairment, one trial. Early death was insensitive to hazard in all six trials where late death or dependency was most sensitive. Two trials (both phase II) did not report the presence of a DMC. CONCLUSIONS: Functional outcome at end of follow-up can be sensitive to hazard and should be included in all assessments of safety in stroke trials, whether or not efficacy itself is being assessed.


Assuntos
Comitês de Monitoramento de Dados de Ensaios Clínicos , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/mortalidade , Ensaios Clínicos como Assunto/normas , Humanos , Segurança , Acidente Vascular Cerebral/tratamento farmacológico
5.
Cochrane Database Syst Rev ; (3): CD002090, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12917919

RESUMO

BACKGROUND: Experimental animal research shows that treatment with amphetamines improves recovery after focal cerebral ischaemia. If the effect were similar in humans, amphetamine treatment could have a major impact on recovery from stroke. OBJECTIVES: The objective of this review was to assess the effects of amphetamine treatment in patients with stroke. SEARCH STRATEGY: We searched the Cochrane Stroke Group Trials Register (last searched November 2002). In addition, we searched the Cochrane Controlled Trials Register (Cochrane Library, Issue 4 2002), MEDLINE (1966-September 2002), EMBASE (1980-November 2002), and Science Citation Index (1992-December 2002). The reference lists of all relevant articles and reviews were checked, and we contacted researchers in the field to identify further published and unpublished studies. SELECTION CRITERIA: Randomized unconfounded trials comparing amphetamine with placebo. DATA COLLECTION AND ANALYSIS: Two reviewers independently selected trials for inclusion, assessed trial quality and extracted the data. MAIN RESULTS: Seven studies involving 172 patients were included. The quality of the trials varied but was generally high. Based on two trials (85 patients) there was no evidence that amphetamine treatment reduced death or dependence (Peto's odds ratio, [Peto OR] 1.54; 95% Confidence Interval [CI] 0.64 to 3.73). In these two trials, there were imbalances at baseline, with more serious strokes allocated to amphetamine. This imbalance may account for the trend for more deaths at the end of follow-up among amphetamine allocated patients (Peto OR 3.33; 95% CI 0.99 to 11.24). Based on 4 studies (95 patients) there was evidence of a better relative change in motor function according to the Fugl-Meyer motor scale (Weighted Mean Difference, [WMD] -8.17 points; 95% CI -13.58 to -2.76) and based on 1 study (21 patients) there was evidence of a better change in language function as assessed by the Porch Index of Communicative Ability score (WMD -7.51 points; 95% CI -14.42 to -0.60) in amphetamine allocated patients. REVIEWER'S CONCLUSIONS: At present, too few patients have been studied to draw any definite conclusions about the effects of amphetamine treatment on recovery from stroke. The suggested benefits on motor and language function, and the non-significant trend towards increased risk of death, could be related to imbalances in prognostic variables or other bias in studies. Further research in this area is therefore justified.


Assuntos
Anfetaminas/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Stroke ; 31(6): 1250-5, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10835440

RESUMO

BACKGROUND AND PURPOSE: The Intravenous Nimodipine West European Stroke Trial (INWEST) found a correlation between nimodipine-induced reduction in blood pressure (BP) and an unfavorable outcome in acute stroke. We sought to confirm this correlation with and without adjustment for prognostic variables and to investigate outcome in subgroups with increasing levels of BP reduction. METHODS: Patients with a clinical diagnosis of ischemic stroke (within 24 hours) were consecutively allocated to receive placebo (n=100), 1 mg/h (low-dose) nimodipine (n=101), or 2 mg/h (high-dose) nimodipine (n=94). The correlation between average BP change during the first 2 days and the outcome at day 21 was analyzed. RESULTS: Two hundred sixty-five patients were included in this analysis (n=92, 93, and 80 for placebo, low dose, and high dose, respectively). Nimodipine treatment resulted in a statistically significant reduction in systolic BP (SBP) and diastolic BP (DBP) from baseline compared with placebo during the first few days. In multivariate analysis, a significant correlation between DBP reduction and worsening of the neurological score was found for the high-dose group (beta=0.49, P=0. 048). Patients with a DBP reduction of > or =20% in the high-dose group had a significantly increased adjusted OR for the compound outcome variable death or dependency (Barthel Index <60) (n/N=25/26, OR 10. 16, 95% CI 1.02 to 101.74) and death alone (n/N=9/26, OR 4.336, 95% CI 1.131 16.619) compared with all placebo patients (n/N=62/92 and 14/92, respectively). There was no correlation between SBP change and outcome. CONCLUSIONS: DBP, but not SBP, reduction was associated with neurological worsening after the intravenous administration of high-dose nimodipine after acute stroke. For low-dose nimodipine, the results were not conclusive. These results do not confirm or exclude a neuroprotective property of nimodipine.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Nimodipina/uso terapêutico , Doença Aguda , Administração Oral , Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/prevenção & controle , Isquemia Encefálica/complicações , Isquemia Encefálica/mortalidade , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/efeitos adversos , Circulação Cerebrovascular/efeitos dos fármacos , Diástole/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipotensão/induzido quimicamente , Hipotensão/complicações , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Nimodipina/administração & dosagem , Nimodipina/efeitos adversos , Índice de Gravidade de Doença , Análise de Sobrevida , Sístole/efeitos dos fármacos , Resultado do Tratamento
8.
Lakartidningen ; 97(14): 1673-6, 2000 Apr 05.
Artigo em Sueco | MEDLINE | ID: mdl-10815393

RESUMO

As carotid endarterectomy is a prophylactic procedure, it would seem particularly important to analyze complications with an aim to avoiding them. All carotid endarterectomies in Sweden are registered, and all serious complications (death and permanent neurological deficit) are analyzed in detail, classified and discussed within the profession. During the period 1994-1996 the frequency was 4.3 percent (technical causes in 17 percent, contraindications in 8 percent and dubious indications in 21 percent, but correct indication and surgery in 54 percent). Thus, even when conditions are optimal there is a certain price to pay for the prevention of ischemic stroke.


Assuntos
Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Garantia da Qualidade dos Cuidados de Saúde , Adulto , Idoso , Estenose das Carótidas/patologia , Contraindicações , Endarterectomia das Carótidas/mortalidade , Endarterectomia das Carótidas/normas , Feminino , Humanos , Masculino , Erros Médicos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/prevenção & controle , Sistema de Registros , Acidente Vascular Cerebral/prevenção & controle , Suécia
9.
Lakartidningen ; 97(14): 1678-82, 1684-5, 2000 Apr 05.
Artigo em Sueco | MEDLINE | ID: mdl-10815394

RESUMO

Carotid surgery prevents recurrent stroke in patients with symptomatic tight stenosis of the carotid artery. The Swedish Carotid Surgery Monitoring Registry seeks to promote selection of patients with significant spontaneous risk for recurrent stroke, with an eye toward expediting evaluation and minimizing surgical complications. To this end, professionals at participating hospitals are informed about their own patient selection and surgery risk in comparison with those in the country as a whole and with set targets. We report the results from the first two years, during which it is estimated that more than half of all patients eligible for carotid surgery in Sweden were included in the registry. Although almost all patients had recent onset of relevant neurological symptoms, less than 60% had a documented tight (80-99% occlusion) stenosis. While the final decision to operate a patient was made within 4 weeks of onset of symptoms for only 18% of the patients the first year, this proportion increased to 33% in the following year. The total incidence of surgery related stroke, myocardial infarct and death was 7.7%, while the incidence of severe stroke, myocardial infarct and death was 3.0%.


Assuntos
Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/normas , Garantia da Qualidade dos Cuidados de Saúde , Sistema de Registros/normas , Amaurose Fugaz/diagnóstico , Amaurose Fugaz/cirurgia , Estenose das Carótidas/diagnóstico , Tomada de Decisões , Endarterectomia das Carótidas/efeitos adversos , Humanos , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/cirurgia , Equipe de Assistência ao Paciente , Seleção de Pacientes , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Oclusão da Artéria Retiniana/diagnóstico , Oclusão da Artéria Retiniana/cirurgia , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Suécia/epidemiologia
10.
Stroke ; 31(1): 82-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10625720

RESUMO

BACKGROUND AND PURPOSE: Clomethiazole is a neuroprotective drug that enhances gamma-aminobutyrate type A (GABA(A)) receptor activity. Its efficacy and safety were tested in the CLomethiazole Acute Stroke Study (CLASS). The protocol allowed a CT scan to be done after randomization but within 7 days of stroke onset to minimize delays before start of treatment. Ninety-five of the 1360 patients randomized were diagnosed as having intracranial hemorrhage rather than ischemic stroke. Safety results for clomethiazole compared with placebo in this group are reported. METHODS: The study included patients with a clinical diagnosis of acute hemispheric cerebral infarction. Treatment was a 24-hour intravenous infusion of 75 mg/kg clomethiazole or placebo. Patients with intracranial hemorrhage discovered on a postrandomization CT were withdrawn from study treatment if treatment was ongoing, and all patients were followed up to 90 days. RESULTS: Ninety-four patients received treatment, 47 in each group. The hemorrhage was classified as intracerebral in 89 patients (94%). Mortality at 90 days was 19.1% in the clomethiazole group and 23.4% in the placebo group. Sedation was the most common adverse event, occurring at a higher incidence in clomethiazole-treated patients (clomethiazole 53%, placebo 17%), followed by rhinitis and coughing. The incidence and pattern of serious adverse events was similar between the treatment groups. The percentage of patients reaching relative functional independence on the Barthel Index (score >/=60) at 90 days was 59.6% in the clomethiazole group and 53.2% in the placebo group. CONCLUSIONS: Clomethiazole appears safe to administer to hemorrhagic stroke patients compared with placebo. These results would obviate the need for a CT scan before therapy is initiated in acute stroke. The safety of clomethiazole in hemorrhagic stroke patients will be further evaluated in a prospective study that is under way in North America.


Assuntos
Clormetiazol/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Doença Aguda , Idoso , Clormetiazol/efeitos adversos , Feminino , Humanos , Infusões Intravenosas , Hemorragias Intracranianas/tratamento farmacológico , Hemorragias Intracranianas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/efeitos adversos , Acidente Vascular Cerebral/fisiopatologia
11.
J Stroke Cerebrovasc Dis ; 9(6 Pt 2): 2-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17895213

RESUMO

There is convincing evidence from animal models of stroke that ischemia leads to an increase in the extracellular concentrations of excitatory amino acids (EAAs), especially glutamate. This accumulation of glutamate, which can reach up to 80 times normal at the centre of an ischemic lesion, is believed to be an important factor for the premature death of neurons that would otherwise survive the ischemic conditions and recover when flow is restored. In the technique of microdialysis, a small probe is inserted into the brain tissue. Fluid passing through the probe is separated from the brain parenchyma by a semipermeable membrane, through which substances released into the brain can diffuse. Analysis of the dialysate allows the nature and time course of release of substances, such as glutamate, to be determined. This technique has been used in patients undergoing resection of cerebral tumors, surgery for epilepsy, head trauma, subarachnoid hemorrhage, and cerebral infarction. Clamping or ligating the blood supply to the lobe about to be excised leads to a rapid accumulation in the dialysate of, among other substances, glutamate. Similar findings have been obtained during lobar resection for the treatment of severe epilepsy. Accumulations of glutamate to approximately 100 times the basal concentration have been found. There are also a few reports of microdialysis being performed in patients undergoing lobectomy after severe strokes or extracranial-intracranial bypass surgery. Again, high concentrations of glutamate have been reported. Another approach is to examine the blood and cerebrospinal fluid (CSF) for traces of EAAs. High concentrations of glutamate have been found in the blood and CSF within 24 hours of the onset of stroke. In animal models, plasma concentrations of glutamate begin to rise some 4 to 6 hours after middle cerebral artery (MCA) occlusions, reaching a peak at about 8 to 24 hours. Similarly, when glutamate is injected into the CSF of rats, there is a lag of approximately 4 hours before the concentration of glutamate in the blood rises. Therefore, it may be possible to detect the ongoing release of glutamate into the brain as a result of cerebral ischemia, which may aid in the selection of the most appropriate treatment. The results of microdialysis and plasma EAA analyses suggest that excitotoxic damage can occur over many hours. This implies that effective neuroprotectant strategies could provide clinical benefits over similarly prolonged periods.

12.
J Stroke Cerebrovasc Dis ; 9(6 Pt 2): 9-14, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17895214

RESUMO

During cerebral ischemia, there is excessive activity of excitatory amino acids, especially glutamate. Activation of glutamate receptors leads to a marked increase in intracellular calcium, which in turn leads to activation of intracellular enzymes and neuronal death--the so-called excitotoxic cascade. The calcium antagonist nimodipine, which acts at L-type calcium channels, was tested for a putative neuroprotectant effect in patients with acute ischemic stroke, but no beneficial effect was demonstrated. Glutamate receptors are attractive targets for neuroprotectant drugs because glutamate plays a central role in the excitotoxic cascade. Clinical trials of NMDA (N-methyl-D-aspartate) antagonists have been disappointing, however, and psychiatric side effects seem to be a general problem with this class of drug. Another strategy proposed for interfering with NMDA receptor function is the infusion of magnesium. The NMDA receptor is normally blocked by magnesium ions and will only respond to glutamate when this magnesium-induced block is removed on depolarization. A large clinical trial to investigate possible neuroprotection by magnesium is underway. The NMDA receptor also has a glycine-binding site and a polyamine-binding site, and the cation channel will only open in response to glutamate if glycine and polyamines are already bound to these obligatory modulatory sites. Gavestinel is selective for the glycine-binding site, and eliprodil for the polyamine site, but large international clinical trials have failed to find any beneficial effects in patients with acute ischemic stroke. Neurotoxic free radicals are also generated during cerebral ischemia. Laboratory stroke models suggest that free radical scavengers might be effective neuroprotectants. One of these, NXY-059, was effective in several animal studies, and preliminary studies in human subjects show that plasma concentrations that are neuroprotective in animal models can be achieved and are well tolerated. Lubeluzole interferes with the glutamate-induced neuronal damage mediated through the formation of nitric oxide. However, a meta-analysis of all clinical trials of lubeluzole was unable to detect a neuroprotectant effect of the drug. There is now some evidence that, in addition to necrosis, some neurons die as a result of apoptosis after cerebral ischemia. Several drugs that interfere with the apoptosis cascade, for example, caspase inhibitors, are under investigation. Clomethiazole ('ZENDRA'; a trademark, the property of the AstraZeneca group of companies) is also undergoing a second large clinical trial in patients with major ischemic strokes. This drug's mechanism of action is not completely clear, but it is known to activate a nonbenzodiazepine site on the GABA(A) (gamma-aminobutyric acid) receptor. This causes increased chloride conductance and hyperpolarization. In vitro clomethiazole inhibits ischemia-induced glutamate efflux from cerebral neurons. The first large controlled trial showed it to be well tolerated and suggested a clinically significant effect in patients with deficits of a major stroke.

13.
J Stroke Cerebrovasc Dis ; 9(6 Pt 2): 32-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17895218

RESUMO

The concept of neuroprotection against the excitotoxic cascade that accompanies ischemic stroke has been proved in animal models. However, no clinical trial has so far shown a statistically significant benefit for a neuroprotectant in patients with acute ischemic stroke on primary end point measures. Some of these failures can be ascribed to poor study design, small sample sizes, or poor choice of primary outcome measures. Trials of NMDA (N-methyl-D-aspartate) antagonists, however, have been troubled by psychotomimetic side effects that may well have meant that the maximal dose that could be tolerated was suboptimal in terms of neuroprotection. Clomethiazole ('ZENDRA'; a trademark, the property of the AstraZeneca group of companies) lacks psychotomimetic side effects and has undergone a large randomized placebo-controlled trial--CLASS (Clomethiazole Acute Stroke Study). This study failed to detect a statistically significant overall effect of clomethiazole. However, a post hoc analysis based on a prospective clinical classification showed that clomethiazole was effective in a subgroup of patients who had deficits of a major stroke. A further clinical trial of clomethiazole in patients with deficits consistent with a major ischemic stroke is currently underway (CLASS-I). In absolute terms, the size of benefit that can be expected from a neuroprotectant may be relatively small, but even small benefits could make the difference between independence and dependence on others for activities of daily living. Even small effects could therefore produce meaningful improvements in quality of life for both patients and their families and could produce significant reductions in long-term costs. The introduction of an effective neuroprotectant will increase the need for stroke to be treated as urgent by both the public and emergency services.

14.
J Stroke Cerebrovasc Dis ; 9(4): 158-65, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-24192021

RESUMO

The Clomethiazole Acute Stroke Study (CLASS) showed no difference in outcome between patients treated with clomethiazole or placebo for all patients treated, but a beneficial effect in patients classified as a total anterior circulation syndrome (TACS). These are patients with clinical symptoms of a large stroke. Safety and tolerability data are reported here with emphasis on the safety of treating stroke patients with a sedative drug. In total, 1,356 patients were eligible for safety analysis. Mortality at 90 days was equal between the treatment groups (clomethiazole, 19.5%; placebo, 19.7%). Clomethiazole was generally well-tolerated. The most common adverse event was sedation (clomethiazole, 53%; placebo, 10%). Clomethiazole also produced some respiratory adverse events (e.g., rhinitis and increased sputum). Serious adverse events associated with sedation were more commonly reported in the clomethiazole group during treatment. However, the incidence was low. There was no difference in the incidence of serious adverse events between the treatment groups for pulmonary conditions, cardiovascular conditions, or other conditions. Clomethiazole produced a small decrease in blood pressure, but this was not associated with a worse outcome. Safety and tolerability in TACS patients was similar to that for all patients treated with the exception that these patients were more sensitive to the sedative effects of the drug. Despite this, mortality was slightly lower, and functional outcome was better in clomethiazole-treated TACS patients compared with placebo. In conclusion, clomethiazole was generally well-tolerated. The sedation observed did not increase the risk for complications, such as pulmonary serious adverse events or affect the outcome in a negative way. Clomethiazole appeared to be safe to use in stroke patients in general and in patients with a large stroke. The efficacy and safety in large strokes will be studied further in a new study, which is ongoing.

16.
Neurology ; 53(7 Suppl 4): S3-14, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10532643

RESUMO

Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) is approved in the United States for treatment of acute ischemic stroke. Approval was granted after a large, randomized, placebo-controlled study by the National Institute of Neurological Disorders and Stroke (NINDS) showed a significant improvement in 3-month outcomes with rtPA despite a significant risk for symptomatic hemorrhage. Two other trials, the first and second European Cooperative Acute Stroke Study (ECASS I and II), have shown comparable results, but neither was statistically positive for the predefined primary end point. An analysis of the risk/benefit profile of rtPA therapy based on the results of these three trials indicates that the treatment is effective and, when administered within 3 hours of symptom onset at a dose of 0.9 mg/kg, the benefits by far outweigh the risks for eligible patients. Even with the 6-hour time window of the two ECASS trials, a combined analysis of the three studies shows the number of disabled or dead patients to be significantly reduced. Preliminary data collected on the use of rtPA outside of clinical trials in the United States and Europe suggest that, when rtPA is used according to the trial protocol, the risks and benefits are similar to those observed in clinical trials. However, even within the United States, rtPA is underutilized. The most substantial treatment barrier is the narrow time window, which may be expanded if long-term experience shows that this is possible. Most stroke patients arrive at the hospital too late to be eligible for screening and treatment. Education of the public and physicians may help to overcome this difficulty.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Ensaios Clínicos Controlados como Assunto/tendências , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/tendências , Doença Aguda , Humanos
18.
Stroke ; 30(1): 21-8, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9880383

RESUMO

BACKGROUND AND PURPOSE: The efficacy and safety of the neuroprotective drug clomethiazole was tested in a double blind placebo controlled trial in patients with a clinical diagnosis of acute hemispheric stroke. METHODS: Patients with symptom onset of /=60 points on the Barthel Index) at 90 days. RESULTS: A total of 1360 patients were included. In the main efficacy analysis (n=1353), 56.1% of patients taking clomethiazole and 54.8% of placebo patients reached relative functional independence. The difference was not statistically significant. An analysis of the effect of time since onset of symptoms showed no difference between the treatment groups. Clomethiazole was generally well tolerated and appeared safe in the population studied. Sedation was the most common adverse event, leading to treatment withdrawal that occurred in 15.6% of clomethiazole-treated patients compared with 4.2% of placebo-treated patients. In a subgroup classified before randomization as having total anterior circulation syndrome (TACS) (n=545, or 40% of all randomized patients), the percentage of those reaching relative functional independence was 40.8% on clomethiazole and 29.8% on placebo, a difference of approximately 11 percentage units. TACS patients have clinical symptoms suggesting a "large" stroke. CONCLUSIONS: Clomethiazole had no adverse or beneficial effect on long-term outcome for all patients but produced sedation. The hypothesis that clomethiazole is effective in patients with large strokes will be tested in a further study.


Assuntos
Transtornos Cerebrovasculares/tratamento farmacológico , Clormetiazol/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/mortalidade , Transtornos Cerebrovasculares/mortalidade , Clormetiazol/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/efeitos adversos , Placebos , Análise de Sobrevida
19.
J Stroke Cerebrovasc Dis ; 8(4): 231-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-17895170

RESUMO

The CLASS study showed no significant difference between treatment groups for the neuroprotectant clomethiazole compared with placebo. However, a beneficial effect of the drug was seen in patients with total anterior circulation syndrome (TACS). These are patients with clinical symptoms suggesting a large stroke. Full results of this subgroup analysis are reported. Patients were classified before randomization using clinical symptoms into the stroke syndromes TACS, partial anterior circulation syndrome, and lacunar syndrome. Subgroup analyses of stroke syndromes were performed post hoc after detecting a treatment by severity interaction. The primary efficacy variable was relative functional independence defined as the proportion of patients scoring > or =60 on the Barthel Index at 90 days. TACS patients (n=546, 40% of all CLASS patients) were more severe at baseline on the 58 point Scandinavian Stroke Scale compared with non-TACS patients (median difference 10 points, mean difference 10.9 points, SE=0.6). Outcome for TACS patients treated with placebo was poor, with only 29.8% reaching relative functional independence. This was increased to 40.8% in the clomethiazole group, a 37% relative benefit, which is clinically significant (odds ratio=1.62, 95% CI 1.13-2.31, nominal P=.008). There was little or no difference in the outcome of non-TACS patients treated with clomethiazole compared with placebo. The treatment effect in TACS patients was quite consistent across participating countries and the 3 parts of the study defined by the 2 interim analyses. The treatment effect seen in patients with clinical symptoms suggesting a large stroke (TACS) is biologically plausible but requires confirmation in a prospective study which is ongoing.

20.
Cerebrovasc Dis ; 8 Suppl 5: 33-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9767197

RESUMO

Neurologic functions improve in most patients days and weeks after onset of a stroke. This can not be explained by recovery of the early salvageable ischemia zone. The most likely mechanism is relearning, a process in which healthy brain takes over functions lost with the infarct. Experimental studies indicate that this recovery can be modulated by pharmacological agents. NMDA antagonists and GABA agonists found to reduce infarct size in stroke models may have a harmful effect on relearning and neurologic recovery. This should be considered when clinical trial protocols are designed.


Assuntos
Transtornos Cerebrovasculares/tratamento farmacológico , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Agonistas GABAérgicos/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Humanos
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