Evaluation of anticoagulants in patients with cerebral infarction with slight to moderate neurological deficit

Anticoagulants for acute ischaemic stroke

BACKGROUND

Stroke is the third leading cause of early death worldwide. Most ischaemic strokes are caused by a blood clot blocking an artery in the brain. Patient outcomes might be improved if they are offered anticoagulants that reduce their risk of developing new blood clots and do not increase the risk of bleeding. This is an update of a Cochrane Review first published in 1995, with updates in 2004, 2008, and 2015.

OBJECTIVES

To assess the effectiveness and safety of early anticoagulation (within the first 14 days of onset) for people with acute presumed or confirmed ischaemic stroke. Our hypotheses were that, compared with a policy of avoiding their use, early anticoagulation would be associated with: • reduced risk of death or dependence in activities of daily living a few months after stroke onset; • reduced risk of early recurrent ischaemic stroke; • increased risk of symptomatic intracranial and extracranial haemorrhage; and • reduced risk of deep vein thrombosis and pulmonary embolism.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (August 2021); the Cochrane Database of Systematic Reviews (CDSR); the Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 7), in the Cochrane Library (searched 5 August 2021); MEDLINE (2014 to 5 August 2021); and Embase (2014 to 5 August 2021). In addition, we searched ongoing trials registries and reference lists of relevant papers. For previous versions of this review, we searched the register of the Antithrombotic Trialists' (ATT) Collaboration, consulted MedStrategy (1995), and contacted relevant drug companies.

SELECTION CRITERIA

Randomised trials comparing early anticoagulant therapy (started within two weeks of stroke onset) with control in people with acute presumed or confirmed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trial quality, and extracted data. We assessed the overall certainty of the evidence for each outcome using RoB1 and GRADE methods.

MAIN RESULTS

We included 28 trials involving 24,025 participants. Quality of the trials varied considerably. We considered some studies to be at unclear or high risk of selection, performance, detection, attrition, or reporting bias. Anticoagulants tested were standard unfractionated heparin, low-molecular-weight heparins, heparinoids, oral anticoagulants, and thrombin inhibitors. Over 90% of the evidence is related to effects of anticoagulant therapy initiated within the first 48 hours of onset. No evidence suggests that early anticoagulation reduced the odds of death or dependence at the end of follow-up (odds ratio (OR) 0.98, 95% confidence interval (CI) 0.92 to 1.03; 12 RCTs, 22,428 participants; high-certainty evidence). Similarly, we found no evidence suggesting that anticoagulant therapy started within the first 14 days of stroke onset reduced the odds of death from all causes (OR 0.99, 95% CI 0.90 to 1.09; 22 RCTs, 22,602 participants; low-certainty evidence) during the treatment period. Although early anticoagulant therapy was associated with fewer recurrent ischaemic strokes (OR 0.75, 95% CI 0.65 to 0.88; 12 RCTs, 21,665 participants; moderate-certainty evidence), it was also associated with an increase in symptomatic intracranial haemorrhage (OR 2.47; 95% CI 1.90 to 3.21; 20 RCTs, 23,221 participants; moderate-certainty evidence). Similarly, early anticoagulation reduced the frequency of symptomatic pulmonary emboli (OR 0.60, 95% CI 0.44 to 0.81; 14 RCTs, 22,544 participants; high-certainty evidence), but this benefit was offset by an increase in extracranial haemorrhage (OR 2.99, 95% CI 2.24 to 3.99; 18 RCTs, 22,255 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Since the last version of this review, four new relevant studies have been published, and conclusions remain consistent. People who have early anticoagulant therapy after acute ischaemic stroke do not demonstrate any net short- or long-term benefit. Treatment with anticoagulants reduced recurrent stroke, deep vein thrombosis, and pulmonary embolism but increased bleeding risk. Data do not support the routine use of any of the currently available anticoagulants for acute ischaemic stroke.

Secondary prophylactic treatment and long-term prognosis after TIA and different subtypes of stroke. A 25-year follow-up hospital-based observational study

OBJECTIVES

To assess long-term prognosis after transient ischemic attack (TIA)/subtypes of stroke relative to secondary prophylactic treatment(s) given.

MATERIALS AND METHODS

Retro/prospective follow-up of patients hospitalized in the Stroke Unit or in the Department of Neurology, Linköping, in 1986 and followed up to Feb. 2011.

RESULTS

A total of 288 men were followed up for 2254 years (mean 7.8 years) and 261 women for 1984 years (mean 7.6 years). In men, the distribution to anticoagulants (AC) (warfarin treatment) was 18%, antiplatelet therapy (APT) usually ASA 75 mg/day 54%, untreated 27%, unknown 2%. In women, the distribution to AC was 15%, APT 60%, untreated 23%, unknown 2%, respectively. Mortality rates at 1 year, 10 years, and 25 years for men were 21%, 67%, and 93%, respectively, versus the rates in women of 24%, 71%, and 90%, respectively. Survival curves showed markedly increased risk of death compared to the normal population. AC treatment was more favorable for men regarding the annual risk of stroke, compared with APT (9.4% vs. 9.8%), as well as the risks of MI, (5.6% vs. 6.7%), and death (8.1% vs. 10.3%), compared to women for stroke (11.6% vs. 8.8%) and MI (5.3% vs. 3.7%) but not for death (8.3% vs. 8.4%). The risk of fatal bleeding was 0.86% annually on AC compared to 0.17% on APT. According to Cox regression analysis included patients with TIA/ischemic stroke, first-line treatment had beneficial effects on survival: AC OR 0.67 (0.5-0.9), APT 0.67 (0.52-0.88) versus untreated.

CONCLUSIONS

Patients with a history of TIA/stroke had a higher mortality rate versus controls, providing support for both primary and secondary prophylaxis regarding vascular risk factors for death. This study also provided support for secondary prophylactic treatment with either AC or ASA (75 mg once daily) to reduce the vascular risk of death unless there are contraindications.

Analytic Review: Ischemic Cerebrovascular Disease: Diagnosis and Management

Ischemic stroke is the most common cause of neurologic morbidity and mortality. The proper management of a stroke patient is dictated by the underlying pathophysiology. An ischemic stroke may occur as a result of restricted flow or thrombosis from atherosclerosis, artery-to-artery embolization, cardiac-to-brain embolization, or disorders of coagulation, to mention a few of the most common causes. Determining the relevant cause of stroke is made more difficult by the coexistence of many possible factors such as hypertension, atherosclerosis, and cardiac disease. Nevertheless, judgments are based on the clinical presentation, computed tomographic scans, cerebral angiograms, and results of echocardiography and electrocardiographic monitoring.

Therapy of the ischemic stroke patient is aimed primarily at preserving areas of potentially recoverable ischemic brain. This is accomplished by correcting or avoiding circumstances that can promote further impairment of ischemic brain. These include proper management of blood pressure, cardiac function, oxygenation, and fluid balance. The role of anticoagulation, hemodilution therapy, and other proposed forms of therapy is often unclear.

Anticoagulants for acute ischaemic stroke

BACKGROUND

Most ischaemic strokes are caused by a blood clot blocking an artery in the brain. Clot prevention with anticoagulants might improve outcomes if bleeding risks are low. This is an update of a Cochrane review first published in 1995, with recent updates in 2004 and 2008.

OBJECTIVES

To assess the effectiveness and safety of early anticoagulation (within the first 14 days of onset) in people with acute presumed or confirmed ischaemic stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (June 2014), the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Database of Systematic Reviews (CDSR), the Database of Reviews of Effects (DARE) and the Health Technology Assessment Database (HTA) (The Cochrane Library 2014 Issue 6), MEDLINE (2008 to June 2014) and EMBASE (2008 to June 2014). In addition, we searched ongoing trials registries and reference lists of relevant papers. For previous versions of this review, we searched the register of the Antithrombotic Trialists' (ATT) Collaboration, consulted MedStrategy (1995), and contacted relevant drug companies.

SELECTION CRITERIA

Randomised trials comparing early anticoagulant therapy (started within two weeks of stroke onset) with control in people with acute presumed or confirmed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trial quality, and extracted the data.

MAIN RESULTS

We included 24 trials involving 23,748 participants. The quality of the trials varied considerably. The anticoagulants tested were standard unfractionated heparin, low-molecular-weight heparins, heparinoids, oral anticoagulants, and thrombin inhibitors. Over 90% of the evidence relates to the effects of anticoagulant therapy initiated within the first 48 hours of onset. Based on 11 trials (22,776 participants) there was no evidence that anticoagulant therapy started within the first 14 days of stroke onset reduced the odds of death from all causes (odds ratio (OR) 1.05; 95% confidence interval (CI) 0.98 to 1.12) at the end of follow-up. Similarly, based on eight trials (22,125 participants), there was no evidence that early anticoagulation reduced the odds of being dead or dependent at the end of follow-up (OR 0.99; 95% CI 0.93 to 1.04). Although early anticoagulant therapy was associated with fewer recurrent ischaemic strokes (OR 0.76; 95% CI 0.65 to 0.88), it was also associated with an increase in symptomatic intracranial haemorrhages (OR 2.55; 95% CI 1.95 to 3.33). Similarly, early anticoagulation reduced the frequency of symptomatic pulmonary emboli (OR 0.60; 95% CI 0.44 to 0.81), but this benefit was offset by an increase in extracranial haemorrhages (OR 2.99; 95% CI 2.24 to 3.99).

AUTHORS' CONCLUSIONS

Since the last version of the review, no new relevant studies have been published and so there is no additional information to change the conclusions. Early anticoagulant therapy is not associated with net short- or long-term benefit in people with acute ischaemic stroke. Treatment with anticoagulants reduced recurrent stroke, deep vein thrombosis and pulmonary embolism, but increased bleeding risk. The data do not support the routine use of any of the currently available anticoagulants in acute ischaemic stroke.

Anticoagulants for preventing recurrence following presumed non-cardioembolic ischaemic stroke or transient ischaemic attack

BACKGROUND

After a first ischaemic stroke, further vascular events due to thromboembolism are common and often fatal. Anticoagulants could potentially reduce the risk of such events, but any benefits could be offset by an increased risk of fatal or disabling haemorrhages.

OBJECTIVES

To assess the effect of prolonged anticoagulant therapy compared with placebo or open control following presumed non-cardioembolic ischaemic stroke or transient ischaemic attack.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register in May 2008. In June 2008 we searched three online trial registers, used Web of Science Cited Reference Search to identify new citations of previously included studies, contacted a pharmaceutical company, and also contacted authors for additional information on included trials.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing at least one month of anticoagulant therapy with control in people with previous, presumed non-cardioembolic, ischaemic stroke or transient ischaemic attack.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trial quality and extracted the data.

MAIN RESULTS

Eleven trials involving 2487 participants were included. The quality of the nine trials which predated routine computerised tomography (CT) scanning and the use of the International Normalised Ratio to monitor anticoagulation was poor. There was no evidence of an effect of anticoagulant therapy on either the odds of death or dependency (two trials, odds ratio (OR) 0.83, 95% confidence interval (CI) 0.52 to 1.34) or of 'non-fatal stroke, myocardial infarction, or vascular death' (four trials, OR 0.96, 95% CI 0.68 to 1.37). Death from any cause (OR 0.95, 95% CI 0.73 to 1.24) and death from vascular causes (OR 0.86, 95% CI 0.66 to 1.13) were not significantly different between treatment and control. The inclusion of two recently completed trials did not alter these conclusions. There was no evidence of an effect of anticoagulant therapy on the risk of recurrent ischaemic stroke (OR 0.85, 95% CI 0.66 to 1.09). However, anticoagulants increased fatal intracranial haemorrhage (OR 2.54, 95% CI 1.19 to 5.45), and major extracranial haemorrhage (OR 3.43, 95% CI 1.94 to 6.08). This is equivalent to anticoagulant therapy causing about 11 additional fatal intracranial haemorrhages and 25 additional major extracranial haemorrhages per year for every 1000 patients given anticoagulant therapy.

AUTHORS' CONCLUSIONS

Compared with control, there was no evidence of benefit from long-term anticoagulant therapy in people with presumed non-cardioembolic ischaemic stroke or transient ischaemic attack, but there was a significant bleeding risk.

Anticoagulants for acute ischaemic stroke

BACKGROUND

Most ischaemic strokes are caused by blood clots blocking an artery in the brain. Clot prevention with anticoagulants might improve outcome if bleeding risks were low. This is an update of a Cochrane review first published in 1995, and previously updated in 2004.

OBJECTIVES

To assess the effect of anticoagulant therapy versus control in the early treatment (less than 14 days) of patients with acute ischaemic stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched 2 October 2007), and two Internet clinical trials registries for relevant ongoing studies (last searched October 2007).

SELECTION CRITERIA

Randomised trials comparing early anticoagulant therapy (started within two weeks of stroke onset) with control in patients with acute presumed or confirmed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, assessed trial quality, and extracted the data.

MAIN RESULTS

Twenty-four trials involving 23,748 participants were included. The quality of the trials varied considerably. The anticoagulants tested were standard unfractionated heparin, low-molecular-weight heparins, heparinoids, oral anticoagulants, and thrombin inhibitors. Based on 11 trials (22,776 participants) there was no evidence that anticoagulant therapy reduced the odds of death from all causes (odds ratio (OR) 1.05; 95% confidence interval (CI) 0.98 to 1.12) at the end of follow up. Similarly, based on eight trials (22,125 participants), there was no evidence that anticoagulants reduced the odds of being dead or dependent at the end of follow up (OR 0.99; 95% CI 0.93 to 1.04). Although anticoagulant therapy was associated with fewer recurrent ischaemic strokes (OR 0.76; 95% CI 0.65 to 0.88), it was also associated with an increase in symptomatic intracranial haemorrhages (OR 2.55; 95% CI 1.95 to 3.33). Similarly, anticoagulants reduced the frequency of pulmonary emboli (OR 0.60; 95% CI 0.44 to 0.81), but this benefit was offset by an increase in extracranial haemorrhages (OR 2.99; 95% CI 2.24 to 3.99).

AUTHORS' CONCLUSIONS

Since the last version of the review, neither of the two new relevant studies have provided additional information to change the conclusions. In patients with acute ischaemic stroke, immediate anticoagulant therapy is not associated with net short or long-term benefit. Treatment with anticoagulants reduced recurrent stroke, deep vein thrombosis and pulmonary embolism, but increased bleeding risk. The data do not support the routine use of any the currently available anticoagulants in acute ischaemic stroke.

Oral anticoagulants and non-cardioembolic stroke prevention

The use of anticoagulants for secondary prevention following non-cardioembolic ischemic stroke is controversial. This systematic review evaluates the safety and efficacy of oral anticoagulation compared with control and antiplatelet therapy.

Anticoagulants for acute ischaemic stroke

BACKGROUND

Most ischaemic strokes are caused by blood clots blocking an artery in the brain. Clot prevention with anticoagulant therapy could have a significant impact on patient survival, disability and stroke recurrence.

OBJECTIVES

The objective of this review was to assess the effect of anticoagulant therapy versus control in the early treatment of patients with acute ischaemic stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group trials register (last searched 30 October 2003). For previous updates of this review, we searched the register of the Antithrombotic Trialists' (ATT) Collaboration, consulted MedStrategy (1995), and contacted relevant drug companies.

SELECTION CRITERIA

Randomised trials comparing early anticoagulant therapy (started within two weeks of stroke onset) with control in patients with acute presumed or confirmed ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected trials for inclusion, assessed trial quality and extracted the data.

MAIN RESULTS

Twenty-two trials involving 23,547 patients were included. The quality of the trials varied considerably. The anticoagulants tested were standard unfractionated heparin, low-molecular-weight heparins, heparinoids, oral anticoagulants, and thrombin inhibitors. Based on nine trials (22,570 patients) there was no evidence that anticoagulant therapy reduced the odds of death from all causes (odds ratio (OR) = 1.05, 95% confidence interval (CI) 0.98 to 1.12) at the end of follow-up. Similarly, based on six trials (21,966 patients), there was no evidence that anticoagulants reduced the odds of being dead or dependent at the end of follow-up (OR = 0.99; 95% CI 0.93 to 1.04). Although anticoagulant therapy was associated with about 9 fewer recurrent ischaemic strokes per 1000 patients treated (OR = 0.76; 95% CI 0.65 to 0.88), it was also associated with a similar sized 9 per 1000 increase in symptomatic intracranial haemorrhages (OR = 2.52; 95% CI 1.92 to 3.30). Similarly, anticoagulants avoided about 4 pulmonary emboli per 1000 (OR = 0.60, 95% CI 0.44 to 0.81), but this benefit was offset by an extra 9 major extracranial haemorrhages per 1000 (OR = 2.99; 95% CI 2.24 to 3.99). Sensitivity analyses did not identify a particular type of anticoagulant regimen or patient characteristic associated with net benefit.

REVIEWERS' CONCLUSIONS

Immediate anticoagulant therapy in patients with acute ischaemic stroke is not associated with net short- or long-term benefit. The data from this review do not support the routine use of any type of anticoagulant in acute ischaemic stroke. People treated with anticoagulants had less chance of developing deep vein thrombosis (DVT) and pulmonary embolism (PE) following their stroke, but these sorts of blood clots are not very common, and may be prevented in other ways.

Risk of haemorrhagic stroke in patients with oral anticoagulation compared with the general population

OBJECTIVES

To compare the incidence of haemorrhagic stroke (HS), and the risk of fatal outcome after HS in patients with oral anticoagulation (OA) treatment and in the general population.

DESIGN

Five-year cohort study.

SETTING

The Anticoagulation Clinic, Malmö University Hospital, Lund, Sweden.

SUBJECTS

A total of 4434 patients treated with OA (6693 treatment years) from 1 Oct 1993 to 30 Sept 1998. The population-based Stroke Register of Malmö, Lund, Sweden (STROMA).

RESULTS

Forty-eight patients had HS according to ICD 9 code 430 and 431. HS occurred at a higher age in women compared with men (mean age 79.5 years vs. 74.7 years, P=0.009). The age-adjusted relative risk of HS during OA treatment was 10.9 (CI 6.7-17.6) for men and 9.3 (CI 5.7-15.0) for women, as compared with the untreated general population. Number needed to harm (NNH) (person-years) was 103 for men and 188 for women. Adjusted for age and sex, OA treatment was significantly associated with fatal outcome in patients with HS (OR=2.6, CI 1.4-4.8).

CONCLUSIONS

Patients with OA treatment had approximately 10 times higher risk of HS as compared with the general population, and the risk increased markedly with age. OA treatment is associated with an increased case fatality in patients with HS.

Anticoagulants for preventing recurrence following presumed non-cardioembolic ischaemic stroke or transient ischaemic attack

BACKGROUND

After a first ischaemic stroke, further vascular events due to thromboembolism (especially myocardial infarction and recurrent stroke) are common and often fatal. Anticoagulants could potentially reduce the risk of such events, but any benefits could be offset by an increased risk of fatal or disabling haemorrhages.

OBJECTIVES

The objective of this review was to assess the effect of prolonged anticoagulant therapy (compared with placebo or open control) following presumed non-cardioembolic ischaemic stroke or transient ischaemic attack.

SEARCH STRATEGY

We searched the Cochrane Stroke Group trials register. We contacted companies marketing anticoagulant agents. The most recent search for this review was carried out in August 2002.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing at least one month of anticoagulant therapy with control in people with previous presumed non-cardioembolic ischaemic stroke or transient ischaemic attack.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected trials for inclusion, assessed trial quality and extracted the data.

MAIN RESULTS

Eleven trials involving 2487 patients were included. The quality of the 9 trials which predated routine computerised tomography scanning and the use of the International Normalised Ratio to monitor anticoagulation was poor. There was no evidence of an effect of anticoagulant therapy on either the odds of death or dependency (two trials, odds ratio 0.83, 95% confidence interval [CI] 0.52 to 1.34) or of 'non-fatal stroke, myocardial infarction, or vascular death' (four trials, odds ratio 0.96, 95% CI 0.68-1.37). Death from any cause (odds ratio 0.95, 95% CI 0.73 to 1.24) and death from vascular causes (odds ratio 0.86, 95% CI 0.66 to 1.13) were not significantly different between treatment and control. The inclusion of two recent completed trials did not alter these conclusions. There was no evidence of an effect of anticoagulant therapy on the risk of recurrent ischaemic stroke (odds ratio 0.85, 95% CI 0.66 to 1.09). However, anticoagulants increased fatal intracranial haemorrhage (odds ratio 2.54, 95% CI 1.19 to 5.45), and major extracranial haemorrhage (odds ratio 3.43, 95% CI 1.94 to 6.08). This is equivalent to anticoagulant therapy causing about 11 additional fatal intracranial haemorrhages and 25 additional major extracranial haemorrhages per year for every 1000 patients given anticoagulant therapy.

REVIEWER'S CONCLUSIONS

Compared with control, there was no evidence of benefit from long-term anticoagulant therapy in people with presumed non-cardioembolic ischaemic stroke or transient ischaemic attack, but there was a significant bleeding risk.

Oral anticoagulants and intracranial hemorrhage. Facts and hypotheses

BACKGROUND

Intracranial hemorrhage is the most feared and lethal complication of oral anticoagulation. We review the frequency, predictors, and prognosis of this most common neurological complication of oral anticoagulation.

SUMMARY OF REVIEW

Anticoagulation to conventional intensities increases the risk of intracranial hemorrhage 7- to 10-fold, to an absolute rate of nearly 1%/y for many stroke-prone patients. Most (70%) anticoagulant-related intracranial hemorrhages are intracerebral hematomas (approximately 60% are fatal); the bulk of the remainder are subdural hematomas. Predictors of anticoagulant-related intracerebral hematoma are advanced patient age, prior ischemic stroke, hypertension, and intensity of anticoagulation. In approximately half of anticoagulated patients with intracerebral hematoma the bleeding evolves slowly over 12 to 24 hours, and emergency reversal of anticoagulation is crucial.

CONCLUSION

Both patient factors and anticoagulation intensity importantly influence the rate of anticoagulation-related intracranial hemorrhage. Patient-related risk factors for this complication overlap with those for ischemic stroke. The risk/benefit equation of anticoagulation for elderly, stroke-prone patients is complex and differs from that for younger patients. The absolute rate reduction (not the relative risk reduction) of ischemic stroke by anticoagulation is the critical issue and must offset accentuation of often lethal brain hemorrhage.

Stroke rates in patients with lacunar and large vessel cerebral infarctions

A stroke registry was developed to determine the value of various clinical data in distinguishing lacunar from large vessel infarctions. Adequate localization was achieved in 98% of 246 patients with brain infarcts. These and 30 transient ischemic attack patients were followed for a median of 1082 days (range 2-1657). Follow-up data on TIA patients were invalidated by evidence of serious underreporting of TIAs in our general population. Among 212 male patients with cerebral infarcts not due to cardiogenic embolism, syphilis, migraine, vasculitis, or other unusual etiologies, 1-, 12-, and 36-month recurrence rates were 23%, 31% and 39% among patients with large vessel anterior circulation infarcts; 15%, 20% and 28% among patients with large vessel posterior circulation infarcts; and 8%, 16% and 21% among patients with lacunar anterior circulation infarcts, respectively. Six patients with posterior circulation lacunes did not experience recurrence. Comparative case fatality data were also compiled. Large vessel infarcts tended to be followed by further large vessel infarcts, usually in the same vascular distribution, whereas lacunar infarcts were not predictive of the type or location of subsequent events.

Differences in the outcome of patients with TIA versus minor stroke

In the Swedish aspirin low dose trial (SALT) 101 patients were enrolled from the Department of Medicine, Falun. 42 patients had experienced TIA/amaurosis fugax, whereas 59 patients had suffered a minor stroke/retinal infarction. History of hypertension treated or known untreated occurred statistically more frequently in the minor stroke group at randomisation (P less than 0.01) and the mean diastolic blood pressure (DBP) was higher in the minor stroke group during the observation time (P less than 0.05; ANOVA). The minor stroke group had less favourable outcomes according to survival curves (stroke or death) during a mean observation time of 34 months in each group (P less than 0.05 at 29 months). The findings of the present trial suggest that hypertension and the higher mean DBP during the observation time might explain the better outcome of end points of stroke or death in patients with TIA.

Haemorrhagic and thromboembolic complications in patients with atrial fibrillation on anticoagulant prophylaxis

We studied clinically relevant haemorrhagic and thromboembolic events in 213 patients with atrial fibrillation (AF) during 818 patient-years of anticoagulant (AC) treatment. The incidence of complicating events per 100 patient-years of treatment in three groups of patients, those with mitral valve disease (MVD; n = 34), without MVD (n = 102) and those with previous thromboembolism (TE; n = 77) was: major peripheral haemorrhages 3.1, 3.3 and 8.2 (non-MVD vs. TE group, P less than 0.05), cerebrovascular events 3.9, 3.0 and 3.0 (NS), and peripheral arterial thromboembolism 0, 0 and 1.5 (non-MVD vs. TE group, P less than 0.05). The proportion of thrombotest values less than 5 and/or greater than 20% at regular check-ups was 9.8% in patients with and 6.9% in patients without major peripheral haemorrhages (P less than 0.01). Major peripheral haemorrhages are frequent in patients with AF receiving AC treatment. They are most likely to occur in those with previous thromboembolism and among those with unstable AC control.

Hemorrhagic complications of long-term anticoagulant therapy for ischemic cerebral vascular disease

The main complication of anticoagulant therapy is bleeding. Although the use of long-term oral anticoagulants in patients with transient cerebral ischemia and/or minor stroke is controversial, anticoagulants are still used in some instances. We have carried out a literature review of the risk of hemorrhage during long-term oral anticoagulant therapy in patients with cerebrovascular disease to determine the rate of bleeding and the clinical and laboratory risk factors which predispose patients to bleeding. The risk of bleeding was substantial with major bleeding episodes ranging from 2% to 22% per year and fatal bleeds from 2% to 9% per year. Only hypertension emerged as an identifiable risk factor and its presence increased the relative risk of bleeding to more than two fold. Major bleeding was almost always intracranial, possibly because of associated hypertension or because of cerebrovascular disease per se. We could not detect a relationship between bleeding and the intensity of anticoagulant therapy, although major bleeding occurred frequently even with only moderately intense anticoagulant therapy. The net gain or loss in efficacy rate of treating patients with minor stroke with long-term oral anticoagulant therapy was examined and it was concluded that in order for such treatment to be beneficial, a risk reduction of more than 50% in stroke rate, and a major bleeding rate of less than 2% per year are required. Since the risk reduction for stroke and death with anticoagulant therapy is unlikely to be 50% and the risk of major bleeding likely to be more than 2%, the present evidence does not support the use of anticoagulant therapy in minor stroke.

Enteric-coated acetylsalicylic acid plus dipyridamole compared with anticoagulants in the prevention of ischemic events in patients with transient ischemic attacks

From December 1976 through March 1982, 188 patients entered an open non-random study carried out on hospitalized patients with a history of transient ischemic attacks or amaurosis fugax. Ninety-two patients received peroral anticoagulants usually combined with heparin treatment during the first days of treatment, and 96 patients enteric-coated acetylsalicylic acid 0,5 g twice daily plus dipyridamole 75 mg twice daily. The patients were followed up to March 1983, irrespective of whether treatment was changed or not. Recurrent transient ischemic attack or amaurosis fugax occurred more frequently (P less than 0.01) from 2 months of follow-up and throughout the observation period in the antiplatelet-treated group. There were no statistically significant differences between the 2 groups on the originally given treatment for endpoints such as stroke (6 patients on anticoagulants, 12 patients on antiplatelet therapy) or stroke or death (11 patients on anticoagulants, 17 patients on antiplatelet therapy). The findings from this trial suggest that anticoagulant treatment is superior to antiplatelet therapy given in the prevention of ischemic attacks and that this difference mainly exists during the first one to 2 months after onset of transient ischemic attacks or amaurosis fugax.