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A Algra

Publications and source records attributed to A Algra.

At least 73 records · Page 4Linked to original sources
PubMed2003

The RATIO study: oral contraceptives and the risk of peripheral arterial disease in young women.

With regard to oral contraceptives, much research has concentrated on venous thrombosis and on the coronary and cerebral forms of atherosclerotic disease, while peripheral arterial disease (PAD) has received little attention. In this case-control study, we assessed oral contraceptive use and the risk of PAD in young women using a population-based case-control study. The women were 18-49 years of age, and had been admitted to a collaborating hospital between January 1990 and October 1995, and had a diagnosis of PAD. Participants were patients with PAD (n = 152), and control women (n = 925), identified by random digit dialing. The diagnosis of PAD was based almost exclusively on intra-arterial angiography. Patients and control subjects filled out the same structured questionnaire, which included questions on medical history, cardiovascular risk factors, and contraceptive use. The adjusted odds ratio for PAD in women using any type of oral contraceptives vs. no use, was 3.8 (95% CI 2.4-5.8). When first generation oral contraceptive use was compared with no use, the odds ratio was 8.7 (95% CI 3.6-21.3). For second and third generation oral contraceptives, the adjusted odds ratios (compared with non-users) were 2.6 (95% CI 1.4-4.9) and 3.0 (95% CI 1.4-6.6), respectively. This is the first study on oral contraceptive use and PAD in humans. All types of oral contraceptives were associated with an increased risk of PAD.

Adult↗
PubMed2003

Informed consent in trials for neurological emergencies: the example of subarachnoid haemorrhage.

BACKGROUND: In patients with acute life threatening diseases, and in their relatives, the ability to make a balanced decision on participation in a clinical trial may be impaired. OBJECTIVES: To assess what relevant information could be recalled by patients who were living independently after a subarachnoid haemorrhage, and by their relatives; and to determine how these patients and relatives had reacted to the informed consent encounter. METHODS: Twenty months (range 7 to 31) after treatment for subarachnoid haemorrhage, 49 patients and 47 relatives who had participated in one of two randomised trials on medical management were interviewed. The interview consisted of items on: spontaneous recall and knowledge of trial design; understanding of the trial design and the informed consent procedure; the amount and clarity of the information given; and reasons for participating. Finally patients and relatives were asked whether they would participate again in similar circumstances. RESULTS: One third of the patients recalled having participated in a clinical trial. Thirteen per cent of the patients and 20% of the relatives felt that the information supplied had not been sufficient. Nine per cent of the patients and half the relatives had read the written information. None of the patients and one relative thought that participation had been obligatory. Twenty eight per cent of the patients and 94% of the relatives felt in retrospect that they had been capable of making an adequate decision. Virtually all patients and relatives would participate again in similar circumstances. CONCLUSIONS: Many patients and their relatives have little recall of the informed consent procedure and the essentials of acute subarachnoid haemorrhage trials. However, most were satisfied with the overall procedure and would participate again.

Decision Making↗
PubMed2002

Long-term prognosis after recovery from primary intracerebral hemorrhage.

BACKGROUND: Little is known about the long-term outcome for patients who recover from a primary intracerebral hemorrhage. The authors examined the rate of recurrence, vascular events, and death in survivors of a primary intracerebral hemorrhage and the factors related to the long-term prognosis. METHODS: All 243 patients admitted to one of three hospitals with a primary intracerebral hemorrhage who regained independence were interviewed about vascular events after the index hemorrhage. The authors used the Kaplan-Meier method to estimate the event-free survival and Cox proportional hazards regression analysis to identify predictors of recurrence, any vascular event, or death. RESULTS: During a mean follow-up of 5.5 years, the annual rates of recurrent primary intracerebral hemorrhage, vascular events, and vascular death were 2.1% (95% CI, 1.4 to 3.3%), 5.9% (95% CI, 4.5 to 7.7%), and 3.2% (95% CI, 2.2 to 4.5%). Age of 65 years or older was the only predictor of a recurrence (hazard ratio [HR], 2.8; 95% CI, 1.3 to 6.1) and vascular death (HR, 3.7; 95% CI, 2.0 to 7.0). In addition to age, male sex predicted the occurrence of vascular events (HR, 1.8; 95% CI, 1.1 to 3.0). Use of anticoagulation after the index bleeding tripled the risk of hemorrhagic events (HR, 3.0; 95% CI, 1.3 to 7.2). CONCLUSION: Patients who recovered from a primary intracerebral hemorrhage had a 2.1% to 5.9% annual rate of recurrence, vascular death, or vascular events. Age of 65 years or older more than doubled the risk of recurrence, vascular event, or death. The risk of vascular events in men was increased twofold.

Aged↗
PubMed2002

[A new instrument to measure clinical outcomes].

De Haan et al. have developed a new disability score (Amsterdam linear disability score; ALDS) based on item response theory. The advantages of the instrument are its generic applicability for multiple disease categories of varying severity and its linear scaling as a continuous variable, which facilitates interpretation and requires smaller sample sizes. Moreover, such a tool may very well be used as complementary outcome measure in a subset of patients participating in a mega-trial that concentrates on simple outcomes. A limitation is that users of the score still need to become familiar with its interpretation. It is not yet clear how many questions are needed to obtain a reliable estimate of the ALDS and therefore the time needed to complete the instrument is still uncertain.

Humans↗
PubMed2002

The effect of tirilazad mesylate on infarct volume of patients with acute ischemic stroke.

The authors investigated whether the lack of effect of tirilazad on clinical outcome in patients with acute ischemic stroke is explained by failure of tirilazad to reduce infarct volume. Overall, tirilazad had no significant effect on infarct volume. In the subgroups of male patients and of those with a cortical infarct, tirilazad significantly reduced infarct volume. These effects were reduced to nonsignificant trends after adjustment for imbalances in baseline characteristics. In conclusion, early treatment of patients with tirilazad has no effect on infarct volume.

Aged↗
PubMed2002

Homocysteine and the stage of atherosclerotic disease: a study in patients suffering from clinically silent and clinically manifest atherosclerotic disease.

BACKGROUND: Elevated serum levels of homocysteine are considered a risk factor for cardiovascular disease. It has been suggested that homocysteine is a late stage predictor of adverse cardiovascular events, which might explain reported controversies in literature. The objective of the present study was to study the relationship between homocysteine levels and the stage of atherosclerotic disease. METHODS: In a cross-sectional study we compared the prevalence of hyperhomocysteinemia in high risk patients without silent or clinically overt atherosclerosis (group I, n = 196) with two patient groups: patients with clinically manifest atherosclerosis in the past or asymptomatic atherosclerosis (group II, n = 364) and patients who currently suffer from a clinically relevant manifestation of ischemic cardiovascular disease (group III, n = 967). In addition, we related homocysteine levels with a cumulative index of atherosclerotic disease (SMART-score). RESULTS: Homocysteine levels (micromol L(-1)) for the different groups were 13.5 +/- 8.9 (group I), 13.7 +/- 8.2 (group II) and 14.7 +/- 7.7 (group III). After adjustment for age, body mass index, creatinine levels and current use of vitamins, no significant differences in the prevalence of hyperhomocysteinemia were observed, compared with the reference category. Linear regression analysis revealed a significant relationship between Smart score and homocysteine levels that remained after adjustment for potential confounders (Beta = 0.36 (0.14-0.59), P = 0.001). CONCLUSION: If homocysteine levels are associated with the presence and indicators of atherosclerotic plaque burden, then this relationship is apparently not affected by the stage of atherosclerotic disease.

Adult↗
PubMed2002

The relation between Helicobacter pylori and atherosclerosis cannot be explained by a high homocysteine concentration.

BACKGROUND: Recent studies have suggested that a chronic infection with Helicobacter pylori might be an independent risk factor for atherosclerosis. However, a direct role in atherogenesis is not plausible, since the bacterium has not been isolated from atherosclerotic lesions. An indirect mechanism that could link H. pylori with atherosclerosis might be through an increase in plasma homocysteine concentration caused by deficiencies of vitamin B12 and folate in plasma. MATERIALS AND METHODS: In 150 female patients with peripheral arterial disease (PAD) and in 412 healthy control women from a nation-wide population-based case-control study, blood samples were collected to determine the antibody titre against H. pylori and to measure plasma homocysteine, folate and vitamin B12 levels. First, the odds ratio for PAD in women with a positive antibody titre against H. pylori was calculated and adjusted for homocysteine level. Secondly, mean concentrations of vitamin B12, folate and homocysteine were compared in healthy controls with a positive or negative antibody titre against H. pylori. Thirdly, the relation between H. pylori and PAD in individuals with a normal or high homocysteine level was investigated. RESULTS: A positive immunoglobulin G antibody titre against H. pylori was found in 42% of the PAD patients and in 27% of the controls. The age- and socio-economic-status (SES) adjusted odds ratio for PAD was 1.5 (95%CI; 1.0-2.2). Additional adjustment for homocysteine plasma concentration did not essentially change the odds ratio. Secondly, among the healthy controls, the homocysteine plasma concentration did not depend on the immunoglobulin G titre, neither did the folate plasma concentration. The concentration of vitamin B12 was slightly higher in women with a positive titre. Thirdly, H. pylori infection was a risk factor for PAD in subjects with a normal homocysteine concentration [OR 2.0 (95%CI 1.3-3.1)]. CONCLUSIONS: This study shows a relationship between a positive immunoglobulin G antibody titre against H. pylori and PAD in young women. Moreover, this study does not support the hypothesis that H. pylori infection is related to atherosclerosis via an increase in plasma homocysteine concentration.

Adolescent↗
PubMed2002

The influence of hyperhomocysteinemia on graft patency after infrainguinal bypass surgery in the Dutch BOA Study.

OBJECTIVE: Hyperhomocysteinemia has been identified as a risk factor for (cardio)vascular disease. Whether hyperhomocysteinemia contributes to graft failure after peripheral bypass surgery remains unclear. The present study evaluated the influence of hyperhomocysteinemia on graft patency after infrainguinal bypass surgery. DESIGN: The present study was designed as a nested case-control study. METHOD: In this study (nested in the Dutch Bypass Oral anticoagulants or Aspirin Study), 150 patients with graft occlusion were each matched with two randomly selected controls with patent grafts (N = 299) from the same trial. Venous blood samples were drawn from cases and controls, and total plasma homocysteine (tHcy) was determined. Mean serum homocysteine levels and the presence of hyperhomocysteinemia (>95th percentile in healthy individuals) were compared between cases and controls. RESULTS: No significant differences were found between serum levels of homocysteine in patients with and without graft occlusion. The mean plasma homocysteine levels were 14.4 micromol/L and 14.9 micromol/L in the case and control groups, respectively. The resulting mean difference was -0.4 (95% confidence interval [CI], -1.8-0.9). The odds ratio of hyperhomocysteinemia was 0.81 (95% CI, 0.49-1.33). Adjustment for risk factors of graft occlusion did not change these results. CONCLUSIONS: Postoperative raised serum levels of homocysteine proved not to be a risk factor for graft occlusion after infrainguinal bypass grafting.

Aged↗
PubMed2002

Effect of second- and third-generation oral contraceptives on fibrinolysis in the absence or presence of the factor V Leiden mutation.

Third-generation oral contraceptives (OC) have been associated with an increased risk of venous thrombosis compared with second-generation OC. To find an explanation for this increased risk, the effect of a second- and third-generation OC and of the progestagens used in these pills on several fibrinolytic parameters was studied in the absence or presence of the factor V Leiden mutation. In a single-center, double-blind trial, 51 women without and 35 women with the factor V Leiden mutation were randomized to either a second-generation (30 microg ethinylestradiol/150 microg levonorgestrel) or a third-generation (30 microg ethinylestradiol/150 microg desogestrel) oral contraceptive. After two menstrual cycles of use and a wash-out period of two cycles, the participants received the corresponding progestagen-only preparation containing 150 microg levonorgestrel or 150 microg desogestrel. D-Dimers, thrombin-activatable fibrinolysis inhibitor (TAFI) and the clot lysis time in the absence (LYSmin) or the presence (LYSplus) of a blocking anti-factor XI antibody were determined in plasmas of the participating women, and the mean difference in changes between the OC were calculated. Both combined OC induced increased plasma levels of D-dimers and TAFI, and induced a prolongation of LYSplus, whereas LYSmin hardly changed. Virtually no changes in fibrinolytic parameters were observed for the progestagen-only preparations. No differential effects between levonorgestrel- and desogestrel-containing OC were found in women without factor V Leiden. Women with the mutation on levonorgestrel-containing OC showed an increased LYSplus compared with desogestrel containing OC (3.9; 95% confidence interval, 0.1-7.7). When using progestagen-only preparations, no differential effect on the fibrinolytic parameters were found, except for non-carriers on levonorgestrel who showed a reduced LYSmin compared with non-carriers on desogestrel (-4.0; 95% confidence interval, -7.8 to -0.2). In conclusion, the effect of oral contraceptives on fibrinolytic parameters is largely independent of the type of progestagen. The increased fibrinolytic activity during OC use appears to be induced by the estrogen component and may be counteracted by increased TAFI activation. This may result in an enhanced downregulation of fibrinolysis.

Activated Protein C Resistance↗
PubMed2002

Effects of second and third generation oral contraceptives and their respective progestagens on the coagulation system in the absence or presence of the factor V Leiden mutation.

Compared to second generation, the use of third generation oral contraceptives has been associated with an increased risk of venous thrombosis especially in women with the factor V Leiden mutation. To find an explanation for these risk differences we investigated the effects of desogestrel- and levonorgestrel-containing oral contraceptives as well as their progestagens separately on the coagulation system in the absence or presence of the factor V Leiden mutation. In a single center, double blind trial, 51 women without and 35 women with the factor V Leiden mutation were randomized to either a second generation (30 microg ethinylestradiol/150 microg levonorgestrel) or a third generation (30 microg ethinylestradiol/150 microg desogestrel) oral contraceptive. After two cycles of use and a wash-out period of 2 menstrual cycles, the participants received the corresponding progestagen-only preparation containing 150 microg levonorgestrel or 150 microg desogestrel. In plasmas of the participating women fragment 1+2, factor V, VII, VIII, IX, X and XI were determined. Both combined oral contraceptives induced a decrease in factor V, whereas the levels of all other coagulant parameters increased. However, in women without the factor V Leiden mutation the effects of desogestrel-containing preparations were significantly different compared to levonorgestrel-containing oral contraceptives for factor V (-8.0; 95% CI -13.4 to -2.6), factor VII (26.8; 95% CI 15.5 to 38.0) and factor IX (-9.6; 95% CI -16.2 to -3.2). When these women used progestagen-only pills, a differential effect between desogestrel and levonorgestrel was only found for factor IX (-6.5; 95% CI -11.4 to -1.5). In carriers of the factor V Leiden mutation desogestrel-containing oral contraceptives induced more pronounced changes in factor V (-14.2; 95% CI -22.4 to -6.0) and factor VII (36.1; 95% CI 19.7 to 52.6) compared to levonorgestrel-containing oral contraceptives. Comparing desogestrel- and levonorgestrel-only, only for factor V a differential effect was found in these women (-9.5; 95% CI -18.3 to -0.6). It appears that desogestrel-containing oral contraceptives have a more pronounced effect on the coagulation system than levonorgestrel-containing oral contraceptives which may be explained by a less effective compensation of the thrombotic effect of ethinylestradiol by desogestrel.

Activated Protein C Resistance↗
PubMed2002

Interobserver agreement in the assessment of lobar versus deep location of intracerebral haematomas on CT.

In patients with supratentorial intracerebral haemorrhage (ICH), it is important to discriminate superficial (lobar) and deep (basal ganglia) location, since this has consequences for research and prognosis. Haemorrhages at these sites have different causes and different risk factors. We studied the interobserver variation between three radiologists in classifying fifty large haematomas on CT as deep or lobar. The kappa values were almost perfect, ranging from 0.88 to 0.96. We conclude that the assessment of CT by radiologist is a reliable method to discriminate between lobar versus deep origin even for large intracerebral haematomas.

Adult↗
PubMed2001

Oral contraceptives and the risk of myocardial infarction.

BACKGROUND: An association between the use of oral contraceptives and the risk of myocardial infarction has been found in some, but not all, studies. We investigated this association, according to the type of progestagen included in third-generation (i.e., desogestrel or gestodene) and second-generation (i.e., levonorgestrel) oral contraceptives, the dose of estrogen, and the presence or absence of prothrombotic mutations METHODS: In a nationwide, population-based, case-control study, we identified and enrolled 248 women 18 through 49 years of age who had had a first myocardial infarction between 1990 and 1995 and 925 control women who had not had a myocardial infarction and who were matched for age, calendar year of the index event, and area of residence. Subjects supplied information on oral-contraceptive use and major cardiovascular risk factors. An analysis for factor V Leiden and the G20210A mutation in the prothrombin gene was conducted in 217 patients and 763 controls RESULTS: The odds ratio for myocardial infarction among women who used any type of combined oral contraceptive, as compared with nonusers, was 2.0 (95 percent confidence interval, 1.5 to 2.8). The adjusted odds ratio was 2.5 (95 percent confidence interval, 1.5 to 4.1) among women who used second-generation oral contraceptives and 1.3 (95 percent confidence interval, 0.7 to 2.5) among those who used third-generation oral contraceptives. Among women who used oral contraceptives, the odds ratio was 2.1 (95 percent confidence interval, 1.5 to 3.0) for those without a prothrombotic mutation and 1.9 (95 percent confidence interval, 0.6 to 5.5) for those with a mutation CONCLUSIONS: The risk of myocardial infarction was increased among women who used second-generation oral contraceptives. The results with respect to the use of third-generation oral contraceptives were inconclusive but suggested that the risk was lower than the risk associated with second-generation oral contraceptives. The risk of myocardial infarction was similar among women who used oral contraceptives whether or not they had a prothrombotic mutation.

Adolescent↗
PubMed2001

Oral anticoagulation for cerebral ischemia of arterial origin: high initial bleeding risk.

BACKGROUND: The use of oral anticoagulant therapy for the prevention of arterial thromboembolism in patients who have had ischemic stroke is controversial. Coumarins may increase the bleeding risk in patients with cerebral ischemia of arterial origin. OBJECTIVES: 1) To calculate incidence rates of bleeding and thromboembolic events in patients with noncardiac cerebral ischemia who were treated routinely in an anticoagulation clinic. 2) To assess which factors contribute to the occurrence of events. 3) To determine the optimal intensity of oral anticoagulant therapy in these patients. METHODS: The authors studied all patients treated for noncardiac cerebral ischemia at the Leiden anticoagulation clinic between 1993 and 1998. Outcome events were major hemorrhage, major arterial thromboembolism, and death. RESULTS: The authors observed 356 patients for 644 patient-years. The incidence of major hemorrhage was 3.9 per 100 patient-years (95% CI, 2.5 to 5.7) and that of thromboembolism was 3.0 per 100 patient-years (95% CI, 1.8 to 4.6). The incidence of hemorrhage varied with the duration of treatment (relative risk [RR] of the first versus the second half-year, 3.8; 95% CI, 1.9 to 7.6), age (RR for age >65 years, 3.7; 95% CI, 1.1 to 12.3), and the intensity of oral anticoagulation (RR, 1.8 for each 0.5 international normalized ratio [INR] unit increase; 95% CI, 1.5 to 2.3). The optimal intensity of oral anticoagulant therapy was 2.5 to 3.5 INR; the best target value was 3.0 INR. CONCLUSION: The risk of hemorrhage with anticoagulant therapy is high in patients with ischemic stroke of arterial origin but is mainly confined to early use and elderly patients.

Adult↗
PubMed2001

Third generation oral contraceptives and risk of venous thrombosis: meta-analysis.

OBJECTIVE: To evaluate quantitatively articles that compared effects of second and third generation oral contraceptives on risk of venous thrombosis. DESIGN: Meta-analysis. STUDIES: Cohort and case-control studies assessing risk of venous thromboembolism among women using oral contraceptives before October 1995. MAIN OUTCOME MEASURES: Pooled adjusted odds ratios calculated by a general variance based random effects method. When possible, two by two tables were extracted and combined by the Mantel-Haenszel method. RESULTS: The overall adjusted odds ratio for third versus second generation oral contraceptives was 1.7 (95% confidence interval 1.4 to 2.0; seven studies). Similar risks were found when oral contraceptives containing desogestrel or gestodene were compared with those containing levonorgestrel. Among first time users, the odds ratio for third versus second generation preparations was 3.1 (2.0 to 4.6; four studies). The odds ratio was 2.5 (1.6 to 4.1; five studies) for short term users compared with 2.0 (1.4 to 2.7; five studies) for longer term users. The odds ratio was 1.3 (1.0 to 1.7) in studies funded by the pharmaceutical industry and 2.3 (1.7 to 3.2) in other studies. Differences in age and certainty of diagnosis of venous thrombosis did not affect the results. CONCLUSIONS: This meta-analysis supports the view that third generation oral contraceptives are associated with an increased risk of venous thrombosis compared with second generation oral contraceptives. The increase cannot be explained by several potential biases.

Adult↗
PubMed2001

Risk, causes, and prevention of ischaemic stroke in elderly patients with symptomatic internal-carotid-artery stenosis.

BACKGROUND: Carotid endarterectomy benefits patients with symptomatic stenosis of 70-99% in the internal carotid artery, with smaller benefit for 50-69% stenosis. The benefit of carotid endarterectomy in patients of 75 years and older remains unclear. METHODS: Patients aged 75 years or older from the North American Symptomatic Carotid Endarterectomy Trial were compared with those aged 65-74 years and less than 65 years for baseline characteristics and risk of ipsilateral ischaemic stroke at 2 years by degree of stenosis and treatment group. FINDINGS: Among patients with 70-99% stenosis, the absolute risk reduction of ipsilateral ischaemic stroke with carotid endarterectomy was 28.9% (95% CI 12.9-44.9) for patients aged 75 years or older (n=71), 15.1% (7.2-23.0) for those aged 65-74 years (n=285), and 9.7% (1.5-17.9) for the youngest group (n=303). Among patients with 50-69% stenosis, the absolute risk reduction was significant only in those of 75 years and older (n=145; 17.3% [6.6-28.0]). The perioperative risk of stroke and death at any degree of stenosis was 5.2% for the oldest group, 5.5% for 65-74 years, and 7.9% for less than 65 years. The number of patients aged 75 years or older needed to treat to prevent one ipsilateral stroke within 2 years was three with 70-99% stenosis and six with 50-69% stenosis. INTERPRETATION: In the prevention of ipsilateral ischaemic stroke, elderly patients with 50-99% symptomatic carotid stenosis benefited more from carotid endarterectomy than younger patients did. To achieve this treatment benefit, surgeons must be skilled and patients with other life-threatening illnesses must be excluded.

Aged↗
PubMed2001

[Surgery for a recently symptomatic severe carotid stenosis, indicated or not? Clinical application of 'evidence-based' medicine].

Two trials have shown that carotid surgery reduced the risk of stroke or death for patients with a recently symptomatic severe carotid stenosis. Nevertheless, it remains difficult to advise in individual cases. The risk of a stroke is about 20% in the next 3 years on medical treatment alone. This means that surgery is of no value in about 80% of the patients. With the help of prediction rules (developed by Rothwell and Warlow) it is possible to further individualize the decision whether or not to operate, by incorporating factors such as the angiographic roughness of the stenosis lining, the time since the cerebrovascular symptoms appeared, the extent of the stenosis, increased operation risk, sex, peripheral vascular disease and systolic blood pressure. If these prediction rules prove to be correct, doctors will be able to better advise their individual patients.

Carotid Stenosis↗
PubMed2001

Oral anticoagulants versus antiplatelet therapy for preventing further vascular events after transient ischaemic attack or minor stroke of presumed arterial origin.

BACKGROUND: Patients who are entered in clinical trials after a transient ischaemic attack (TIA) or non disabling ischaemic stroke have an annual risk of important vascular events (death from all vascular causes, non-fatal stroke, or non-fatal myocardial infarction) of between 4 and 11 percent. Aspirin, in a daily dose of 30mg or more, offers only modest protection after cerebral ischaemia: it reduces the incidence of major vascular events by 20 percent at most. Secondary prevention trials after myocardial infarction indicate that treatment with oral anticoagulants is associated with a risk reduction approximately twice that of treatment with antiplatelet therapy. OBJECTIVES: 1) To compare the efficacy of oral anticoagulants and antiplatelet therapy in the secondary prevention of vascular events after cerebral ischaemia of presumed arterial origin. 2) To compare the safety of oral anticoagulants and antiplatelet therapy in the secondary prevention of vascular events after cerebral ischaemia of presumed arterial origin. SEARCH STRATEGY: This review draws on the search strategy developed for the Stroke Group as a whole. Relevant trials were identified in the Specialised Register of Controlled Trials (last searched: June 2000). Authors of published trials were contacted for further information and unpublished data. SELECTION CRITERIA: Randomised trials with concealed treatment allocation on long term (> 6 months) secondary prevention after recent (< 6 months) TIA or minor ischaemic stroke of presumed arterial origin were selected. The oral anticoagulant therapy was to be of specified intensity (by means of the International Normalised Ratio (INR)) with warfarin, phenprocoumon or acenocoumarol versus a single antiplatelet drug (or combination of antiplatelet agents). DATA COLLECTION AND ANALYSIS: Two reviewers selected trials meeting the inclusion criteria and extracted details of randomisation methods, blinding of treatments and assessments, whether intention-to-treat analysis is possible from the published data, whether treatment groups are comparable with regard to major prognostic risk factors for outcomes, the number of patients who are excluded or lost to follow-up, definition of outcomes, and entry and exclusion criteria. The methodological quality of each trial was assessed by the two reviewers using these extracted data. In addition, target INR for anticoagulant treatment and dose and type of antiplatelet drug, duration of follow-up and the numbers of defined outcome events was recorded. The data were analysed according to the intention-to-treat principle. Subgroup analyses with treatment INR 2.1 - 3.6 versus INR 3.0 - 4.5 was performed. Relative and absolute risk reductions were calculated by means of the statistical software provided by the Cochrane Collaboration. MAIN RESULTS: Four trials, with a total of 1870 patients were selected. In the prevention of ischaemic stroke after cerebral ischaemia of presumed arterial origin, the available data do not allow a robust conclusion on whether anticoagulants (in any intensity) are more efficacious than antiplatelet therapy (low intensity anticoagulation RR 0.96, 95% CI 0.38 to 2.42, high intensity anticoagulation RR 1.02, 95% CI 0.49 to 2.13). Treatment with anticoagulation INR 2.1 - 3.6 does not give an importantly higher bleeding risk than treatment with antiplatelet agents (RR 1.19, 95% CI 0.59 to 2.41). It is clear that oral anticoagulants INR 3.0 - 4.5 are not safe, because they yield a higher risk of major bleeding complications (RR 9.0, 95% CI 3.9 to 21). REVIEWER'S CONCLUSIONS: For the secondary prevention of further vascular events after transient ischaemic attack or minor stroke of presumed arterial origin, there is insufficient evidence to justify the routine use of low intensity oral anticoagulants (INR 2.0 - 3.6). More intense anticoagulation (INR 3.0 - 4.5) is not safe and should not be used in this setting.

Administration, Oral↗