Change in stroke incidence, mortality, case-fatality, severity, and risk factors in Oxfordshire, UK from 1981 to 2004 (Oxford Vascular Study)

Background The incidence of stroke is predicted to rise because of the rapidly ageing population. However, over the past two decades, findings of randomised trials have identified several interventions that are effective in prevention of stroke. Reliable data on time-trends in stroke incidence, major risk factors, and use of preventive treatments in an ageing population are required to ascertain whether implementation of preventive strategies can offset the predicted rise in stroke incidence. We aimed to obtain these data. Methods We ascertained changes in incidence of transient ischaemic attack and stroke, risk factors, and premorbid use of preventive treatments from 1981–84 (Oxford Community Stroke Project; OCSP) to 2002–04 (Oxford Vascular Study; OXVASC). Findings Of 476 patients with transient ischaemic attacks or strokes in OXVASC, 262 strokes and 93 transient ischaemic attacks were incident events. Despite more complete case-ascertainment than in OCSP, age-adjusted and sex-adjusted incidence of first-ever stroke fell by 29% (relative incidence 0·71, 95% CI 0·61–0·83, p=0·0002). Incidence declined by more than 50% for primary intracerebral haemorrhage (0·47, 0·27–0·83, p=0·01) but was unchanged for subarachnoid haemorrhage (0·83, 0·44–1·57, p=0·57). Thus, although 28% more incident strokes (366 vs 286) were expected in OXVASC due to demographic change alone (33% increase in those aged 75 or older), the observed number fell (262 vs 286). Major reductions were recorded in mortality rates for incident stroke (0.63, 0.44–0.90, p=0.02) and in incidence of disabling or fatal stroke (0·60, 0·50–0·73, p<0·0001), but no change was seen in case-fatality due to incident stroke (17·2% vs 17·8%; age and sex adjusted relative risk 0·85, 95% CI 0·57-1·28, p=0·45). Comparison of premorbid risk factors revealed substantial reductions in the proportion of smokers, mean total cholesterol, and mean systolic and diastolic blood pressures and major increases in premorbid treatment with antiplatelet, lipid-lowering, and blood pressure lowering drugs (all p<0.0001). Interpretation The age-specific incidence of major stroke in Oxfordshire has fallen by 40% over the past 20 years in association with increased use of preventive treatments and major reductions in premorbid risk factors

VITATOPS, the VITAmins TO Prevent Stroke Trial: Rationale and design of a randomised trial of B-vitamin therapy in patients with recent transient ischaemic attack or stroke (NCT00097669) (ISRCTN74743444)

Background Epidemiological studies suggest that raised plasma concentrations of total homocysteine (tHcy) may be a common, causal and treatable risk factor for atherothromboembolic ischaemic stroke, dementia and depression. Although tHcy can be lowered effectively with small doses of folic acid, vitamin B12 and vitamin B6, it is not known whether lowering tHcy, by means of B vitamin therapy, can prevent stroke and other major atherothromboembolic vascular events. Aim To determine whether the addition of B-vitamin supplements (folic acid 2 mg, B6 25 mg, B12 500 μg) to best medical and surgical management will reduce the combined incidence of stroke, myocardial infarction (MI) and vascular death in patients with recent stroke or transient ischaemic attack (TIA) of the brain or eye. Design A prospective, international, multicentre, randomised, double blind, placebo-controlled clinical trial. Setting One hundred and four medical centres in 20 countries on five continents. Subjects Eight thousand (6600 recruited as of 5 January, 2006) patients with recent (7 months) stroke (ischaemic or haemorrhagic) or TIA (brain or eye). Randomisation Randomisation and data collection are performed by means of a central telephone service or secure internet site. Intervention One tablet daily of either placebo or B vitamins (folic acid 2mg, B6 25 mg, B12 500 μg). Primary outcome The composite of stroke, MI or death from any vascular cause, whichever occurs first. Outcome and serious adverse events are adjudicated blinded to treatment allocation. Secondary outcomes TIA, unstable angina, revascularisation procedures, dementia, depression. Statistical power With 8000 patients followed up for a median of 2 years and an annual incidence of the primary outcome of 8% among patients assigned placebo, the study will have at least 80% power to detect a relative reduction of 15% in the incidence of the primary outcome among patients assigned B vitamins (to 6·8%/year), applying a two-tailed level of significance of 5%. Conclusion VITATOPS aims to recruit and follow-up 8000 patients between 1998 and 2008, and provide a reliable estimate of the safety and effectiveness of folic acid, vitamin B12, and vitamin B6 supplementation in reducing recurrent serious vascular events among a wide range of patients with TIA and stroke throughout the world. The VITATOPS Trial Study Grou

General anaesthesia versus local anaesthesia for carotid surgery (GALA): a multicentre, randomised controlled trial

BACKGROUND: The effect of carotid endarterectomy in lowering the risk of stroke ipsilateral to severe atherosclerotic carotid-artery stenosis is offset by complications during or soon after surgery. We compared surgery under general anaesthesia with that under local anaesthesia because prediction and avoidance of perioperative strokes might be easier under local anaesthesia than under general anaesthesia. METHODS: We undertook a parallel group, multicentre, randomised controlled trial of 3526 patients with symptomatic or asymptomatic carotid stenosis from 95 centres in 24 countries. Participants were randomly assigned to surgery under general (n=1753) or local (n=1773) anaesthesia between June, 1999 and October, 2007. The primary outcome was the proportion of patients with stroke (including retinal infarction), myocardial infarction, or death between randomisation and 30 days after surgery. Analysis was by intention to treat. The trial is registered with Current Control Trials number ISRCTN00525237. FINDINGS: A primary outcome occurred in 84 (4.8%) patients assigned to surgery under general anaesthesia and 80 (4.5%) of those assigned to surgery under local anaesthesia; three events per 1000 treated were prevented with local anaesthesia (95% CI -11 to 17; risk ratio [RR] 0.94 [95% CI 0.70 to 1.27]). The two groups did not significantly differ for quality of life, length of hospital stay, or the primary outcome in the prespecified subgroups of age, contralateral carotid occlusion, and baseline surgical risk. INTERPRETATION: We have not shown a definite difference in outcomes between general and local anaesthesia for carotid surgery. The anaesthetist and surgeon, in consultation with the patient, should decide which anaesthetic technique to use on an individual basis. FUNDING: The Health Foundation (UK) and European Society of Vascular Surgery