科研之友
微信
新浪微博
Facebook
分享链接
摘要
In the UK, about 150,000 people have a stroke each year. About 30% die within 6 months and another 30% survive dependent on others for everyday activities, making stroke the commonest cause of dependency in adults and the second commonest cause of death in the world. 1,2 Stroke is estimated to cost the NHS between f4.6(3) and 7B pound per year. (4) Stroke is also one of the major causes of disability in adults. 5 Eighty per cent of strokes are ischaemic, and most (75%) ischaemic strokes are due to an artery in the brain becoming blocked by atherothromboembolism. Treatment of ischaemic stroke is limited to thrombolysis, which can be used only in the first few hours after the stroke, 6 a minor effect of aspirin, and co-ordinated stroke unit care, so prevention is vital. %26lt;br%26gt;About 20-40% of people have a warning transient ischaemic attack (TIA) or minor non-disabling ischaemic stroke shortly before they have a major disabling stroke. 7,8 In the UK, there are estimated to be 80,000-90,000 TIAs per year. 9 If these people can be assessed quickly, potential stroke causes identified and treated appropriately to reduce risk, then many of these disabling strokes can be prevented. 10 Based on these figures, the average regional hospital serving a population of around 750,000 will see about 1000 suspected TIA/minor stroke cases per year, i.e. about 20 per week. Delivering effective stroke prevention to this number of people is challenging and requires highly organised stroke services that are able to respond rapidly, accurately and effectively for stroke prevention, while avoiding adverse affects on other services within finite resources. The personal, societal, public health and financial burden of stroke in the UK is such that every effort should be made to limit the damaging effects of having a major disabling stroke, and to determine how to make best use of our available resources. (5,11-13) %26lt;br%26gt;Transient ischaemic attack is defined as a sudden loss of focal cerebral or monocular function lasting less than 24 hours due to inadequate cerebral or ocular blood supply as a result of low blood flow, thrombosis or embolism associated with disease of the arteries, heart or blood%26apos;. 14 Although the definition of TIA purely on the basis of clinical grounds is the subject of debate, 15,16 and a tissue-based definition has been proposed, 17 for the present time we have used the clinical definition. Patients with minor stroke, which differs from TIA only by symptoms or signs lasting more than 24 hours, are also at high risk of early recurrent stroke and need the same assessment and treatment as for patients with TIA to prevent a further disabling stroke or death. A small proportion of TIA/minor stroke (%26lt; 5%) (18)-(20) is actually due to a small haemorrhage in the brain but this can be distinguished from ischaemic stroke only by brain scanning. %26lt;br%26gt;The period of highest risk of disabling stroke is in the first few hours and days after a TIA minor stroke, thus making suspected TIA/minor stroke a medical emergency: 8,14,21,22 the Oxford Vascular Study (OXVASC) suggested that between 8.0% and 11.5% of patients will have a recurrent stroke by 1 week, and between 11.5% and 15.0% by 1 month after TIA/minor stroke unless effective secondary prevention is started. 9 In the USA, there are about 240,000 TIAs per annum, of whom 25% had experienced a further TIA, a stroke or died by 3 months. 23 Prevention of recurrent ischaemic stroke is by rapid identification of underlying risk factors [such as ipsilateral tight carotid artery stenosis, atrial fibrillation (AF), hypercholesterolaemia, hypertension] and implementation of optimal medical (antiplatelet agents, statins, antihypertensive drugs or anticoagulant drugs where necessary) 10,14,24 and surgical treatment (endarterectomy for symptomatic moderate to severe carotid stenosis). (25) %26lt;br%26gt;Hence, patients with definite acute ischaemic stroke are now given standard quadruple preventative therapy [antiplatelet agent, statin, angiotensin-converting enzyme (ACE) inhibitor and diuretic drug] and patients who present with suspected TIA/minor stroke are started on quadruple therapy pending specialist investigation and treatment. It is therefore important to ensure that the patients whose symptoms after due investigation are proven not to be caused by acute ischaemic cerebrovascular (CV) disease, particularly the small proportion (approximate to 5%) whose symptoms are due to a small haemorrhage, then avoid inappropriate, ineffective, expensive, unnecessary or possibly hazardous(26)-(30) drug treatment.
- 出版日期2014-4
