Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 174
Filter
Add more filters

Publication year range
1.
Br J Surg ; 97(8): 1218-25, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20602498

ABSTRACT

BACKGROUND: Health outcomes and costs are both important when deciding whether general (GA) or local (LA) anaesthesia should be used during carotid endarterectomy. The aim of this study was to assess the cost-effectiveness of carotid endarterectomy under LA or GA in patients with symptomatic or asymptomatic carotid stenosis for whom surgery was advised. METHODS: Using patient-level data from a large, multinational, randomized controlled trial (GALA Trial) time free from stroke, myocardial infarction or death, and costs incurred were evaluated. The cost-effectiveness outcome was incremental cost per day free from an event, within a time horizon of 30 days. RESULTS: A patient undergoing carotid endarterectomy under LA incurred fewer costs (mean difference pound178) and had a slightly longer event-free survival (difference 0.16 days, but the 95 per cent confidence limits around this estimate were wide) compared with a patient who had GA. Existing uncertainty did not have a significant impact on the decision to adopt LA, over a wide range of willingness-to-pay values. CONCLUSION: If cost-effectiveness was considered in the decision to adopt GA or LA for carotid endarterectomy, given the evidence provided by this study, LA is likely to be the favoured treatment for patients for whom either anaesthetic approach is clinically appropriate.


Subject(s)
Anesthesia, General/economics , Anesthesia, Local/economics , Carotid Stenosis/economics , Endarterectomy, Carotid/economics , Postoperative Complications/etiology , Adult , Aged , Carotid Stenosis/surgery , Cost-Benefit Analysis , Disease-Free Survival , Humans , Length of Stay , Middle Aged , Myocardial Infarction/etiology , Postoperative Complications/economics , Stroke/etiology
2.
Lancet ; 372(9656): 2132-42, 2008 Dec 20.
Article in English | MEDLINE | ID: mdl-19041130

ABSTRACT

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.


Subject(s)
Anesthesia, General , Anesthesia, Local , Carotid Stenosis/surgery , Postoperative Complications/mortality , Postoperative Complications/prevention & control , Stroke/mortality , Stroke/prevention & control , Aged , Carotid Stenosis/complications , Endarterectomy, Carotid , Female , Humans , Male , Postoperative Complications/etiology , Stroke/etiology
3.
Clin Med (Lond) ; 7(6): 589-92, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18193707

ABSTRACT

Carotid endarterectomy (CEA) is of benefit for stroke prevention in the presence of severe carotid stenosis, provided surgical morbidity and mortality are acceptably low. To assess the current performance of CEA in the UK, an interim analysis of 30-day postoperative outcome data, blinded to anaesthetic allocation, from the first 1,001 UK patients randomised in the GALA Trial (multicentre randomised trial of general versus local anaesthesia for CEA) took place and the time from last symptomatic event to surgery was recorded. The 30-day risk of stroke was 5.3%, myocardial infarction (MI) 0.4%, death 1.7%, and stroke, MI or death 6.4%. Median delay between symptoms and surgery was 82 days. These risks are similar to those reported in the large randomised trials of CEA, but current delays to surgery are excessive and must have substantially reduced the benefit of endarterectomy.


Subject(s)
Carotid Stenosis/surgery , Endarterectomy, Carotid/methods , Stroke/prevention & control , Aged , Carotid Stenosis/complications , Carotid Stenosis/epidemiology , Confidence Intervals , Female , Follow-Up Studies , Humans , Incidence , Male , Retrospective Studies , Risk Factors , Stroke/epidemiology , Stroke/etiology , Time Factors , Treatment Outcome , United Kingdom/epidemiology
4.
Lancet ; 366(9479): 29-36, 2005.
Article in English | MEDLINE | ID: mdl-15993230

ABSTRACT

BACKGROUND: Effective early management of patients with transient ischaemic attacks (TIA) is undermined by an inability to predict who is at highest early risk of stroke. METHODS: We derived a score for 7-day risk of stroke in a population-based cohort of patients (n=209) with a probable or definite TIA (Oxfordshire Community Stroke Project; OCSP), and validated the score in a similar population-based cohort (Oxford Vascular Study; OXVASC, n=190). We assessed likely clinical usefulness to front-line health services by using the score to stratify all patients with suspected TIA referred to OXVASC (n=378, outcome: 7-day risk of stroke) and to a hospital-based weekly TIA clinic (n=210; outcome: risk of stroke before appointment). RESULTS: A six-point score derived in the OCSP (age [> or =60 years=1], blood pressure [systolic >140 mm Hg and/or diastolic > or =90 mm Hg=1], clinical features [unilateral weakness=2, speech disturbance without weakness=1, other=0], and duration of symptoms in min [> or =60=2, 10-59=1, <10=0]; ABCD) was highly predictive of 7-day risk of stroke in OXVASC patients with probable or definite TIA (p<0.0001), in the OXVASC population-based cohort of all referrals with suspected TIA (p<0.0001), and in the hospital-based weekly TIA clinic-referred cohort (p=0.006). In the OXVASC suspected TIA cohort, 19 of 20 (95%) strokes occurred in 101 (27%) patients with a score of 5 or greater: 7-day risk was 0.4% (95% CI 0-1.1) in 274 (73%) patients with a score less than 5, 12.1% (4.2-20.0) in 66 (18%) with a score of 5, and 31.4% (16.0-46.8) in 35 (9%) with a score of 6. In the hospital-referred clinic cohort, 14 (7.5%) patients had a stroke before their scheduled appointment, all with a score of 4 or greater. CONCLUSIONS: Risk of stroke during the 7 days after TIA seems to be highly predictable. Although further validations and refinements are needed, the ABCD score can be used in routine clinical practice to identify high-risk individuals who need emergency investigation and treatment.


Subject(s)
Ischemic Attack, Transient/complications , Stroke/diagnosis , Aged , Cohort Studies , Early Diagnosis , Humans , Middle Aged , Risk Factors , Stroke/complications
5.
Cochrane Database Syst Rev ; (1): CD003436, 2006 Jan 25.
Article in English | MEDLINE | ID: mdl-16437454

ABSTRACT

BACKGROUND: Brain arteriovenous malformations (AVMs) are the single most common cause of intracerebral haemorrhage in young adults. Brain AVMs also cause seizure(s) and focal neurological deficits (in the absence of haemorrhage, migraine or an epileptic seizure); approximately one fifth are incidental discoveries. Various interventions are used in an attempt to eradicate brain AVMs: neurosurgical excision, stereotactic radiotherapy/'radiosurgery' (using gamma knife, linear accelerator or proton beam), endovascular embolisation (using glues, particles, fibres, coils, or balloons), and staged combinations of these interventions. OBJECTIVES: To assess the clinical effects of interventions to treat brain AVMs in adults (with the aim of either partial obliteration or total eradication), using data published in randomised controlled trials. SEARCH STRATEGY: We searched: (1) the Cochrane Stroke Group Register (last searched December 2004); (2) medical literature databases (MEDLINE 1966 to 31 December 2004 and EMBASE 1980 to 31 December 2004); (3) on-line and paper journal surveillance; (4) the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2005); (5) international registers of clinical trials; (6) bibliographies of relevant articles identified by (1) to (5); and (7) we sought unpublished data from manufacturers of interventional treatments for brain AVMs. SELECTION CRITERIA: We sought randomised trials of any or all of the interventions for brain AVMs, compared against each other or against usual medical therapy, with relevant clinical outcome measures. DATA COLLECTION AND ANALYSIS: Two authors independently applied the inclusion criteria and reviewed the relevant studies. MAIN RESULTS: We did not find any randomised trials meeting our selection criteria. We found two randomised trials which tested the equivalence of two embolic agents for the pre-operative embolisation of brain AVMs (one published, one unpublished), but none of the primary or secondary outcome measures in these trials met our desired criteria; although important clinical outcomes were reported, meaningful comparison of the two treatment arms was impossible. We also excluded a third RCT which studied three different blood pressure lowering treatments to induce deliberate hypotension during surgical resection of brain AVMs, because the intervention was not the focus of this review. AUTHORS' CONCLUSIONS: There is no evidence from randomised trials with clear clinical outcomes, comparing different interventional treatments for brain AVMs against each other or against usual medical therapy, to guide the interventional treatment of brain AVMs in adults. One such trial (ARUBA), comparing interventional versus conservative management for unruptured brain AVMs, is being planned.


Subject(s)
Intracranial Arteriovenous Malformations/therapy , Adult , Humans
6.
Lancet ; 363(9413): 915-24, 2004 Mar 20.
Article in English | MEDLINE | ID: mdl-15043958

ABSTRACT

BACKGROUND: Carotid endarterectomy reduces the risk of stroke in patients with recently symptomatic stenosis. Benefit depends on the degree of stenosis, and we aimed to see whether it might also depend on other clinical and angiographic characteristics, and on the timing of surgery. METHODS: We analysed pooled data from the European Carotid Surgery Trial and North American Symptomatic Carotid Endarterectomy Trial. The risk of ipsilateral ischaemic stroke for patients on medical treatment, the perioperative risk of stroke and death, and the overall benefit from surgery were determined in relation to seven predefined and seven post hoc subgroups. RESULTS: 5893 patients with 33000 patient-years of follow-up were analysed. Sex (p=0.003), age (p=0.03), and time from the last symptomatic event to randomisation (p=0.009) modified the effectiveness of surgery. Benefit from surgery was greatest in men, patients aged 75 years or older, and those randomised within 2 weeks after their last ischaemic event, and fell rapidly with increasing delay. For patients with 50% or higher stenosis, the number of patients needed to undergo surgery (ie, number needed to treat) to prevent one ipsilateral stroke in 5 years was nine for men versus 36 for women, five for age 75 years or older versus 18 for younger than 65 years, and five for those randomised within 2 weeks after their last ischaemic event, versus 125 for patients randomised after more than 12 weeks. These results were consistent across the individual trials. INTERPRETATION: Benefit from endarterectomy depends not only on the degree of carotid stenosis, but also on several other clinical characteristics such as delay to surgery after the presenting event. Ideally, the procedure should be done within 2 weeks of the patient's last symptoms.


Subject(s)
Carotid Stenosis/surgery , Endarterectomy/methods , Age Factors , Aged , Carotid Stenosis/classification , Carotid Stenosis/diagnostic imaging , Cerebral Angiography , Female , Follow-Up Studies , Humans , Male , Middle Aged , Patient Selection , Randomized Controlled Trials as Topic , Severity of Illness Index , Sex Factors , Stroke/prevention & control , Survival Analysis , Time Factors
7.
Lancet ; 363(9425): 1925-33, 2004 Jun 12.
Article in English | MEDLINE | ID: mdl-15194251

ABSTRACT

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.


Subject(s)
Stroke/epidemiology , Adult , Aged , Aged, 80 and over , Cerebral Hemorrhage/epidemiology , England/epidemiology , Female , Humans , Incidence , Ischemic Attack, Transient/epidemiology , Male , Middle Aged , Risk Factors , Stroke/diagnosis , Stroke/mortality , Stroke/prevention & control , Subarachnoid Hemorrhage/epidemiology , Survival Rate
8.
Stroke ; 34(2): 514-23, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12574569

ABSTRACT

BACKGROUND AND PURPOSE: The European Carotid Surgery Trial (ECST) and North American Symptomatic Carotid Endarterectomy Trial (NASCET) have shown that endarterectomy reduces the risk of stroke in certain patients with recently symptomatic carotid stenosis. However, they differed in the degree of stenosis above which surgery was reported to be effective. This disparity has led to inconsistent clinical recommendations but may have been due to differences between the trials in the methods of measurement of carotid stenosis and definitions of outcome events. METHODS: To allow direct comparison of analyses from ECST and NASCET, we remeasured the prerandomization ECST carotid angiograms and redefined the outcome events the same way as in NASCET. RESULTS: We randomized 3018 patients and followed them up for a mean of 73 months. Surgery reduced the 5-year risk of any stroke or surgical death by 5.7% (95% CI, 0 to 11.6) in patients with 50% to 69% stenosis (n=646, P=0.05) and by 21.2% (95% CI, 12.9 to 29.4) in patients with 70% to 99% stenosis without "near occlusion" (n=429, P<0.0001). These benefits were maintained at the 10-year follow-up. However, surgery was of no benefit in patients (n=125) with near occlusion. The effect of surgery in this group was highly significantly different from that in patients with 70% to 99% stenosis without near occlusion (P=0.002). Surgery was harmful in patients with <30% stenosis (n=1321, P=0.007) and of no benefit in patients with 30% to 49% stenosis (n=478, P=0.6). CONCLUSIONS: Results of the ECST and NASCET were consistent when analyzed in the same way. In ECST, surgery was highly beneficial for 70% to 99% stenosis and moderately beneficial for 50% to 69% stenosis. However, contrary to clinical recommendations and current practice, surgery was of little benefit in patients with carotid near occlusion.


Subject(s)
Carotid Arteries/surgery , Carotid Stenosis/surgery , Endarterectomy, Carotid , Stroke/prevention & control , Aged , Angiography/statistics & numerical data , Carotid Arteries/diagnostic imaging , Carotid Stenosis/diagnostic imaging , Disease-Free Survival , Female , Follow-Up Studies , Humans , Male , Middle Aged , Randomized Controlled Trials as Topic/statistics & numerical data , Risk Assessment , Treatment Outcome , Vascular Patency
9.
Stroke ; 31(12): 3008-14, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11108764

ABSTRACT

BACKGROUND AND PURPOSE: It is generally considered that tissue that appears abnormal on T2 MRI is already infarcted and that any penumbra lies outside the T2-visible lesion. We investigated the distribution of infarcted tissue using proton spectroscopic MRI. METHODS: In patients with symptoms of acute hemispheric ischemic stroke, imaged within a maximum of 3 days of stroke, we explored the distribution of N:-acetylaspartate (NAA), a marker of intact neurons, within and around the abnormal (hyperintense) areas on T2-weighted MR images, using proton spectroscopic MRI. RESULTS: In 11 patients, imaged 24 to 72 hours after stroke onset, there was little evidence of damaged neurons (reduced NAA) beyond the margins of hyperintensity on the T2 image. However, within the abnormal T2 area, there were statistically significant differences in the amount of NAA (ie, the proportion of intact neurons) between areas that were obviously abnormal on T2 (very hyperintense) and those that were only slightly abnormal (slightly hyperintense). CONCLUSIONS: The extent and degree of hyperintensity of the T2-visible lesion directly reflect the amount of neuronal damage; lack of a T2-visible lesion would suggest predominantly intact neurons at the time of imaging. We hypothesize that once tissue damage has reached a critical (probably irreversible) level, the T2 image quickly becomes abnormal without any significant time lag between the pathological staging of the infarct and its visualization on T2. Further testing in a larger study with information on blood flow levels would be required to confirm this.


Subject(s)
Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Brain Ischemia/diagnosis , Brain/metabolism , Magnetic Resonance Imaging/statistics & numerical data , Magnetic Resonance Spectroscopy , Stroke/diagnosis , Acute Disease , Brain Ischemia/metabolism , Cerebral Infarction/diagnosis , Cerebral Infarction/metabolism , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Spectroscopy/statistics & numerical data , Stroke/metabolism
10.
Stroke ; 31(9): 2134-40, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10978042

ABSTRACT

BACKGROUND AND PURPOSE: We measured arterial oxygen saturation (SaO(2)) during eating in acute stroke patients to establish the frequency of any meal-related hypoxemia, which could further damage already vulnerable brain tissue. METHODS: Stroke patients (

Subject(s)
Eating/physiology , Oxygen/blood , Stroke/physiopathology , Acute Disease , Aged , Female , Hospitalization , Humans , Hypoxia/blood , Male , Oximetry , Stroke/blood , Time Factors
11.
Stroke ; 35(12): 2855-61, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15514193

ABSTRACT

BACKGROUND AND PURPOSE: Early studies showed that carotid endarterectomy (CEA) carried a high risk if performed within days after a large ischemic stroke. Therefore, many surgeons delay CEA for 4 to 6 weeks after any stroke. To determine the effect of delay to CEA on operative risk and benefit, we pooled data from the North American Symptomatic Carotid Endarterectomy Trial and the European Carotid Surgery Trial. METHODS: Risk of ipsilateral ischemic stroke in the medical group, operative risk of stroke and death, and overall benefit from surgery were determined in relation to the time from the last symptomatic event to randomization. Operative risk of stroke and death was also determined in relation to the time to surgery. Analyses were stratified by sex and type of presenting event. RESULTS: The 30-day perioperative risk of stroke and death was unrelated to the time since the last symptomatic event and was not increased in patients operated <2 weeks after nondisabling stroke. In contrast, the risk of ipsilateral ischemic stroke in the medical group fell rapidly with time since event (P<0.001), as did the absolute benefit from surgery (P=0.001). This decline in benefit with time was unrelated to the type of presenting event but was more pronounced in women than men (difference P<0.001). Benefit in women was confined to those randomized <2 weeks after their last event, irrespective of severity of stenosis. CONCLUSIONS: CEA can be performed safely within 2 weeks of nondisabling ischemic stroke. Benefit from endarterectomy declines rapidly with increasing delay, particularly in women.


Subject(s)
Endarterectomy, Carotid , Ischemic Attack, Transient/surgery , Stroke/surgery , Aged , Data Interpretation, Statistical , Female , Humans , Male , Middle Aged , Randomized Controlled Trials as Topic , Risk , Sex Factors , Survival Analysis , Time Factors
12.
Stroke ; 35(3): 627-32, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14963282

ABSTRACT

BACKGROUND AND PURPOSE: The importance of stroke in low-income regions such as sub-Saharan Africa has recently been emphasized. However, little is known about the burden of stroke in sub-Saharan Africa. We investigated the prevalence of stroke survivors in the Agincourt Health and Population Unit, a demographic surveillance site in the rural northeast of South Africa. METHODS: Census workers asked household informants 2 screening questions for stroke during the annual census. If either question was answered positively, a clinician visited individuals aged > or =15 years to confirm the likely diagnosis of stroke. We performed a detailed assessment and defined stroke according to the World Health Organization criteria. RESULTS: A total of 42 378 individuals were aged > or =15 years. There were 982 positive responses to the questionnaire, and we examined 724 individuals (74%). We identified 103 strokes (crude prevalence, 243/100 000). After adjustment for those we did not examine, the prevalence was 300/100 000 (95% CI, 250 to 357). Sixty-six percent of stroke survivors needed help with at least 1 activity of daily living (Segi age-standardized prevalence, 200/100 000). CONCLUSIONS: Stroke prevalence in rural South Africa is higher than previously documented in Africa but lower than in high-income countries. However, the prevalence of stroke survivors requiring help with at least 1 activity of daily living is already at high-income country levels. South Africa suffers from a huge burden of HIV/AIDS and diseases of poverty and violence and now faces the challenge of adapting its health systems to face the coming epidemic of vascular disease.


Subject(s)
Rural Population/statistics & numerical data , Stroke/epidemiology , Survivors/statistics & numerical data , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Female , Humans , Male , Mass Screening/methods , Mass Screening/statistics & numerical data , Middle Aged , Population Surveillance , Poverty/statistics & numerical data , Prevalence , Sex Distribution , South Africa/epidemiology
13.
Stroke ; 33(11): 2658-63, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12411657

ABSTRACT

BACKGROUND AND PURPOSE: Carotid endarterectomy (CEA) reduces the risk of stroke ipsilateral to recently symptomatic severe carotid stenosis. Other techniques such as percutaneous transluminal angioplasty with stenting are currently being compared with CEA. Thus far, case series and several small, randomized, controlled trials of CEA versus percutaneous transluminal angioplasty (with and without stenting) have focused primarily on the 30-day procedural risks of stroke and death. However, long-term durability is also important. To determine the long-term risk of stroke after CEA and to identify risk factors, we studied patients in the European Carotid Study Trial (ECST), the largest published cohort with long-term follow-up by physicians after CEA. METHODS: Risks of ipsilateral carotid territory ischemic stroke were calculated by Kaplan-Meier analysis starting on the 30th day after CEA in 1728 patients who underwent trial surgery. Risk factors were determined by Cox regression. For comparison, we also determined the "background" risk of stroke on medical treatment in the ECST in the territory of 558 previously asymptomatic contralateral carotid arteries with <30% angiographic stenosis (ECST method) at randomization. RESULTS: The risks of disabling ipsilateral ischemic stroke and any ipsilateral ischemic stroke were constant after CEA, reaching 4.4% [95% confidence interval (CI), 3.0 to 5.8] and 9.7% (95% CI, 7.6 to 11.7), respectively, by 10 years. The equivalent ischemic stroke risks distal to contralateral <30% asymptomatic carotid stenoses were 1.9% (95% CI, 0.8 to 3.2) and 4.5% (95% CI, 1.5 to 7.4). Presentation with cerebral symptoms, diabetes, elevated systolic blood pressure, smoking, male sex, increasing age, and a lesser severity of preoperative stenosis were associated with an increased risk of late stroke after CEA, but plaque morphology and patch grafting were not. CONCLUSIONS: Although the risk of late ipsilateral ischemic stroke after CEA for symptomatic stenosis is approximately double the background risk in the territory of <30% asymptomatic stenosis, it is still only approximately 1% per year and remains low for at least 10 years after CEA. This is the standard against which alternative treatments should be judged. Several risk factors may be useful in identifying patients at particularly high risk of late postoperative stroke.


Subject(s)
Carotid Stenosis/surgery , Endarterectomy, Carotid/adverse effects , Endarterectomy, Carotid/statistics & numerical data , Postoperative Complications , Stroke/etiology , Carotid Stenosis/epidemiology , Clinical Trials as Topic/statistics & numerical data , Cohort Studies , Europe , Female , Follow-Up Studies , Humans , Male , Postoperative Complications/epidemiology , Proportional Hazards Models , Risk Assessment , Risk Factors , Stroke/epidemiology , Survival Analysis , Time , Treatment Outcome
14.
Stroke ; 32(6): 1370-7, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11387501

ABSTRACT

BACKGROUND AND PURPOSE: This study describes the large variations in outcome after stroke between countries that participated in the International Stroke Trial and seeks to define whether they could be explained by variations in case mix or by other factors. METHODS: We analyzed data from the 15 116 patients recruited in Argentina, Australia, Italy, the Netherlands, Norway, Poland, Sweden, Switzerland, and the United Kingdom: We compared crude case fatality and the proportion of patients dead or dependent at 6 months; we used logistic regression to adjust for age, sex, atrial fibrillation, systolic blood pressure, level of consciousness, and number of neurological deficits. We used the frequency of prerandomization head CT scan and prescription of aspirin at discharge to indicate quality of care. RESULTS: The differences in outcome (all treatment groups combined) between the "best" and "worst" countries were very large for death (171 cases per 1000 patients) and for death or dependency (375 cases per 1000 patients). The differences were somewhat smaller after adjustment for case mix (160 and 311 cases per 1000 patients, respectively). Process of care may have accounted for some but not all of the residual variation in outcome. CONCLUSIONS: Adjustment for case mix explained only some of the variation in outcome between countries. The residual differences in outcome were too large to be explained by variations in care and most likely reflect differences in unmeasured baseline factors. These findings demonstrate the need to achieve balance of treatment and control within each country in multinational randomized controlled stroke trials and the need for caution in the interpretation of nonrandomized comparisons of outcome after stroke between countries.


Subject(s)
Outcome Assessment, Health Care/statistics & numerical data , Randomized Controlled Trials as Topic/statistics & numerical data , Stroke/mortality , Aged , Argentina/epidemiology , Aspirin/therapeutic use , Australia/epidemiology , Europe/epidemiology , Female , Follow-Up Studies , Heparin/therapeutic use , Humans , Logistic Models , Male , Models, Statistical , Outcome Assessment, Health Care/trends , Poland/epidemiology , Predictive Value of Tests , Process Assessment, Health Care/statistics & numerical data , Process Assessment, Health Care/trends , Prognosis , Quality of Health Care , ROC Curve , Severity of Illness Index , Stroke/diagnosis , Stroke/drug therapy , Survival Rate/trends , United Kingdom/epidemiology
15.
Stroke ; 31(9): 2117-26, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10978040

ABSTRACT

BACKGROUND AND PURPOSE: Autopsy series of patients with AIDS have found a 4% to 29% prevalence of cerebral infarction. Little is known of the prevalence of cerebral infarction when not associated with non-HIV central nervous system (CNS) infection, lymphoma, or cardioembolic sources. Clinical correlation has seldom been available. We describe the pathological and clinical features of patients from the Edinburgh HIV Cohort Study found to have had cerebral infarcts without evidence of non-HIV CNS infection, CNS lymphoma, or cardioembolic sources at autopsy. METHODS: From 183 autopsy cases, 26 without evidence of opportunistic cerebral infection or lymphoma were selected. These 26 cases went through a second selection process in which the presence of cerebral infarction, in the absence of the conditions mentioned, was verified. Histology and clinical records for the remaining patients were reviewed. RESULTS: Ten (5.5%) cases fulfilled the inclusion criteria and demonstrated similar hypoxic-ischemic lesions. Small-vessel thickening was seen in all cases, and perivascular space dilatation, rarefaction, and pigment deposition, with vessel wall mineralization and perivascular inflammatory cell infiltrates, were seen in some cases. Vasculitis was not found. One patient had had a transient ischemic attack, and no patient had had a stroke. CONCLUSIONS: Cerebral infarcts in HIV-infected patients are not common in the absence of cerebral non-HIV infection, lymphoma, or embolic sources. We found an HIV-associated vasculopathy with similar features in all risk groups. In AIDS patients presenting with stroke or transient ischemic attack, potentially treatable causes, such as cerebral coinfection or tumor, should be sought.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , Brain Infarction/etiology , Brain/pathology , Acquired Immunodeficiency Syndrome/pathology , Adult , Autopsy , Brain/blood supply , Brain/virology , Brain Infarction/epidemiology , Brain Infarction/pathology , Cohort Studies , Frontal Lobe/virology , HIV Core Protein p24/analysis , Humans , Immunohistochemistry , Microcirculation/pathology , Middle Aged , Prevalence , Scotland/epidemiology , Viral Load
16.
Stroke ; 34(8): e138-40, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12855835

ABSTRACT

BACKGROUND AND PURPOSE: The commonly quoted early risks of stroke after a first transient ischemic attack (TIA)-1% to 2% at 7 days and 2% to 4% at 1 month-are likely to be underestimates because of the delay before inclusion into previous studies and the exclusion of patients who had a stroke during this time. Therefore, it is uncertain how urgently TIA patients should be assessed. We used data from the Oxford Community Stroke Project (OCSP) to estimate the very early stroke risk after a TIA and investigated the potential effects of the delays before specialist assessment. METHODS: All OCSP patients who had a first-ever definite TIA during the study period (n=209) were included. Three analyses were used to estimate the early stroke risk after a first TIA starting from 3 different dates: assessment by a neurologist, referral to the TIA service, and onset of first TIA. RESULTS: The stroke risk from assessment by a neurologist was 1.9% [95% confidence interval (CI), 0.1 to 3.8] at 7 days and 4.4% (95% CI, 1.6 to 7.2) at 30 days. The 7- and 30-day stroke risks from referral were 2.4% (95% CI, 0.3 to 4.5) and 4.9% (95% CI, 1.9 to 7.8), respectively, and from onset of first-ever TIA were 8.6% (95% CI, 4.8 to 12.4) and 12.0% (95% CI, 7.6 to 16.4), respectively. CONCLUSIONS: The early risk of stroke from date of first-ever TIA is likely to be higher than commonly quoted. Public education about the symptoms of TIA is needed so that medical attention is sought more urgently and stroke prevention strategies are implemented sooner.


Subject(s)
Ischemic Attack, Transient/epidemiology , Stroke/epidemiology , Aged , Causality , Comorbidity/trends , Disease-Free Survival , Female , Humans , Male , Prospective Studies , Referral and Consultation/statistics & numerical data , Risk Assessment , Stroke/prevention & control , Survival Analysis , Time Factors , United Kingdom/epidemiology
17.
Arch Neurol ; 52(12): 1215-8, 1995 Dec.
Article in English | MEDLINE | ID: mdl-7492297

ABSTRACT

OBJECTIVE: To identify the policy of international airlines for the carriage of passengers with epilepsy. DESIGN: Postal questionnaire asking about policy for epileptic passengers, training of cabin crew, onboard drugs suitable for the treatment of seizures, and details of any problems reported by crews as a result of in-flight passenger seizures. PARTICIPANTS: The questionnaire was addressed to the medical advisors of 42 international airlines. RESULTS: Thirty (71%) of 42 airlines responded. Eleven (37%) of the 30 airlines that responded had a stated policy or restriction on the carriage of passengers with epilepsy. Five of these airlines advised increasing the dose of anticonvulsant drugs before travel. One airline insisted that epileptic passengers travel with a companion. Twenty-five (83%) of 30 airlines dealt specifically with epilepsy in the training program of their cabin crews. Seventeen (57%) of 30 airlines carried diazepam onboard, mostly in injectable form. Most airlines reported no, or very few, incidents of in-flight passenger seizures annually. CONCLUSIONS: The advice offered to intending epileptic passengers differs greatly between airlines. Some airlines instruct intending passengers to increase their regular medication, probably without justification, since in-flight seizures are very infrequent. Training of cabin crew and the medical equipment carried onboard also vary and in some cases are inadequate.


Subject(s)
Aerospace Medicine , Epilepsy , Organizational Policy , Diazepam/therapeutic use , Epilepsy/drug therapy , Humans , Surveys and Questionnaires
18.
Atherosclerosis ; 21(3): 451-4, 1975.
Article in English | MEDLINE | ID: mdl-807225

ABSTRACT

The administration of ascorbic acid (1g/day) to healthy adults did not significantly influence the levels of serum cholesterol, plasminogen activator activity, plasminogen, fibrinogen, FR-antigen, partial thromboplastin time, platelet adhesiveness, a-1-antitrypsin or a-2-macroglobulin over the 3-month period of study.


Subject(s)
Ascorbic Acid/pharmacology , Blood Coagulation/drug effects , Cholesterol/blood , Platelet Adhesiveness/drug effects , Analysis of Variance , Blood Coagulation Tests , Enzyme Activation/drug effects , Female , Fibrinogen/analysis , Fibrinolysis/drug effects , Hematocrit , Humans , Immunodiffusion , Macroglobulins/analysis , Male , Plasminogen , Thromboplastin , Trypsin Inhibitors/analysis
19.
Thromb Haemost ; 36(1): 127-32, 1976 Aug 31.
Article in English | MEDLINE | ID: mdl-1036801

ABSTRACT

In fifteen patients with a cerebro-vascular accident resulting in an acute hemiplegia there was a subsequent rise in the platelet count and plasma fibrinogen level. There were no significant alterations in platelet adhesiveness, plasminogen activator, plasminogen, FR-antigen and haematocrit. Patients diagnosed as developing deep venous thrombosis with the 125I-fibrinogen technique had a significantly lower platelet adhesiveness and plasminogen level than those who were not.


Subject(s)
Cerebrovascular Disorders/blood , Fibrinolysis , Leg/blood supply , Platelet Adhesiveness , Thrombophlebitis/etiology , Aged , Blood Cell Count , Blood Platelets , Cerebrovascular Disorders/complications , Female , Fibrinogen/analysis , Hematocrit , Humans , Male , Middle Aged
20.
J Clin Pathol ; 25(6): 484-6, 1972 Jun.
Article in English | MEDLINE | ID: mdl-5043373

ABSTRACT

In a study of 41 fasting subjects it was confirmed that fibrinolytic activity was reduced in obese persons: an increase in fibrinogen was also associated with obesity. There was no correlation between obesity and the platelet count, platelet adhesiveness to glass, the level of serum fibrin degradation products, or the whole blood clotting time in plastic tubes.


Subject(s)
Blood Coagulation , Fibrinolysis , Obesity/blood , Platelet Adhesiveness , Blood Cell Count , Blood Coagulation Tests , Body Weight , Fasting , Female , Fibrin/metabolism , Fibrinogen/metabolism , Humans , Male , Plasminogen/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL