摘要:

Level 1 evidence now shows that thrombolysis in cases of acute ischaemic stroke is effective if administered within 3 hours of stroke onset. This benefit has been shown to be time dependent and potentially extends beyond 3 hours, with evidence that potentially viable penumbral tissue may be present in a significant proportion of cases well beyond 3–6 hours and, in isolated cases, perhaps up to 48 hours. This exposes a ‘stroke recovery gap’, the difference observed between the clinical response to thrombolytic therapy in a given population of patients presenting with ischaemic stroke and the potential clinical recovery if all of the penumbra were salvaged under ideal circumstances.The means of bridging this ‘stroke recovery gap’ using thrombolysis must involve extending the therapeutic time window (i.e. the time between stroke onset and administration of thrombolytics). Approaches to do this include the use of:improved patient selection with modern neuroimaging techniques, particularly magnetic resonance imaging using perfusion-weighted image/diffusion-weighted image mismatch;newer thrombolytic agents;lower doses of these agents;varied methods of administration of thrombolytic therapy including combined intravenous and intra-arterial approaches; andadjunctive therapies such as neuroprotectants.Should these means of extending the time window for thrombolysis prove successful, a more widespread use of this form of acute stroke therapy will be possible.

ISSN:1172-7047    

出版商:ADIS    

年代:2003

数据来源: ADIS

摘要:

The relationship between alcohol and seizures is complex and multifaceted. The prevalence of epilepsy in alcohol-dependent patients of western industrialised countries may be at least triple that in the general population, whereas the prevalence of alcoholism is only slightly higher in patients with epilepsy than in the general population.The seizure threshold is raised by alcohol drinking and declines on cessation of drinking. As a result, during withdrawal from alcohol, usually 6–48 hours after the cessation of drinking, seizures may occur. Alcohol acts on the brain through several mechanisms that influence seizure threshold. These include effects on calcium and chloride flux through the ion-gated glutamate NMDA and GABA receptors. During prolonged intoxication, the CNS adapts to the effects of alcohol, resulting in tolerance; however, these adaptive effects seem to be transient, disappearing after alcohol intake is stopped. Although the relationship of seizures to alcohol use is likely to be dose dependent and causal, the available clinical data do not suggest that alcohol use results in seizure genesis. However, a genetic predisposition to alcohol withdrawal seizures is possible. Other seizures in alcohol-dependent individuals may be due to concurrent metabolic, toxic, infectious, traumatic, neoplastic and cerebrovascular diseases and are frequently partial-onset seizures. Alcohol abuse is a major precipitant of status epilepticus (9–25% of cases), which may even be the first-ever seizure type.Prompt treatment of alcohol withdrawal seizures is recommended to prevent status epilepticus. During the detoxification process, primary and secondary preventative measures can be taken. A meta-analysis of controlled trials for the primary prevention of alcohol withdrawal seizures demonstrated a highly significant risk reduction for seizures with benzodiazepines and antiepileptic drugs and an increased risk with antipsychotics. A meta-analysis of randomised, placebo-controlled trials for the secondary prevention of seizures after alcohol withdrawal showed lorazepam to be effective, whereas phenytoin was ineffective. Because withdrawal seizures do not recur if the patient remains abstinent, long-term administration of antiepileptic drugs is unnecessary in abstinent patients. The first seizure not related to alcohol withdrawal should not result in permanent drug treatment in an alcohol-dependent patient, because of poor compliance and the high likelihood of remission. The treatment of alcohol dependence is more important and should be prioritised before the prevention of further seizures.

ISSN:1172-7047    

出版商:ADIS    

年代:2003

数据来源: ADIS

摘要:

In health, the nervous system exists in a balance between inhibitory and excitatory influences. This balance may be upset if neural tissue is damaged or irritated and may give rise to neuropathic pain. Such neuropathic pain does not respond consistently to opioid analgesics or NSAIDs and it may therefore be necessary to utilise other therapeutic agents with known activity on either the excitatory or inhibitory components of the pain pathway. These other agents are traditionally considered with reference to their original uses; we still refer to tricyclic antidepressants (TCAs) and anticonvulsant drugs when a consideration of their modes of action may allow more rational use. For example, carbamazepine is related to the TCAs by virtue of its chemical structure and proposed mode of action and yet is still classified as an anticonvulsant drug.With respect to the opioids, increasing evidence points to an analgesic effect in neuropathic pain, although concerns regarding tolerance and dependence still prevent more widespread use. The anticonvulsants comprise a group of compounds possessing anticonvulsant and analgesic properties, but each possesses differing modes of action and so several members of the class should be tried before a conclusion is reached that they, as a whole, are ineffective. TCAs may also have a role in the treatment of neuropathic pain. As with all drugs, if their use is not associated with pain relief in a defined period of time, their use should be terminated. Topical TCAs may also have a role where the area of neuropathic pain is small. Other options, such as SSRIs, membrane stabilisers, capsaicin, baclofen and clonidine may have potential in treating neuropathic pain.The available evidence regarding the efficacy of currently available agents for the treatment of neuropathic pain is sparse. With the knowledge of achieving analgesia, according to the modes of actions of various agents it is hoped that the treatment of this difficult condition may be more logical and successful.

ISSN:1172-7047    

出版商:ADIS    

年代:2003

数据来源: ADIS

摘要:

ObjectiveThis study aimed to measure the economic value of cholinesterase inhibitors when used to treat Alzheimer’s disease using the willingness-to-pay (WTP) approach and the framework of cost-benefit analysis.Methods and study designA cost-benefit analysis using the WTP approach was employed. The study sample consisted of 28 nonprofessional caregivers of outpatients with mild to moderate dementia from Toronto, ON, Canada. The caregivers were presented with four scenarios. In the first scenario, scenario A, a hypothetical patient with mild dementia was stabilised with a cholinesterase inhibitor. In the second scenario, scenario A with adverse effects, the above patient (A) experienced adverse effects caused by the drug. In the third scenario, scenario B, the patient exhibited behavioural symptoms in addition to mild dementia, and both were stabilised with the drug. In the fourth scenario, scenario B with adverse effects, the above patient (B) experienced adverse effects caused by the drug. The caregivers were then asked what amount they would pay, in Canadian dollars, each year to buy the medication, assuming that they were the caregivers of the patient described. A multivariate regression analysis was performed to assess the relationship between the demographic data (including the caregiver’s yearly income) and the WTP. The average WTP was also predicted for the general population and the elderly population of Canada using data from Statistics Canada, and these values were compared with the cost of the medication.Study perspectiveNonprofessional caregiver perspective. All monetary values are 1999 values unless otherwise specified.ResultsThe mean yearly WTP was $Can4540 (95% CI 2334–6746) for scenario A, $Can3686 (95% CI 1530–5842) for scenario A with adverse effects, $Can5003 (95% CI 2661–7345) for scenario B and $Can4486 (95% CI 2222–6750) for scenario B with adverse effects. The WTP decreased when drug adverse effects were present (significantly in scenario A; p = 0.04), but did not significantly increase when behavioural symptoms were present and stabilised. In all scenarios, caregiver yearly income was the only significant predictor of WTP, in the direction expected. For all scenarios, the calculated WTPs from the regression analysis using our sample mean, the average Canadian population data and the elderly population data were all higher than the yearly cost of the cholinesterase inhibitors, with the net benefit ranging from $Can1723 to $Can4508.ConclusionsThe results of the study, from a small sample of nonprofessional caregivers, revealed that the caregivers are willing to pay more for cholinesterase inhibitors than the drugs cost, even when the adverse effects of the drugs are taken into consideration. This indicates a net benefit for cholinesterase inhibitors in the treatment of mild to moderate dementia from a consumer’s point of view.

ISSN:1172-7047    

出版商:ADIS    

年代:2003

数据来源: ADIS

摘要:

The management of neurological and psychiatric disorders is a vast and evolving area for researchers, primary care physicians and specialists. To help you keep up to date with the latest advances worldwide on all aspects of drug therapy for neurological and psychiatric disorders, this section of the journal brings you information selected from the drug therapy reporting serviceInpharma Weekly1. The following reports are selected from the latest issues, summarising the most important research and development news, clinical studies, treatment guidelines, pharmacological, pharmacoeconomic and adverse drug reactions/interactions news, and expert opinion pieces published across a broad range of literature sources.

ISSN:1172-7047    

出版商:ADIS    

年代:2003

数据来源: ADIS