OBJECTIVES: We searched the Cochrane
Stroke Group Trials Register, the Cochrane Controlled Trials Register (Central/CCTR), the trials register held by the Antithrombotic
Therapy Trialists' Collaboration, MEDLINE (1966-2000), and EMBASE (1980-2000). All searches were performed during April and May 2001.
SELECTION CRITERIA: Both reviewers independently selected trials for inclusion in the review, assessed trial quality and extracted data.
MAIN RESULTS: A total of 16,558 patients from four trials contributed to the analyses. The methodological quality was high in all four trials. The
anticoagulants tested were
unfractionated heparin (UFH) and
low molecular-weight heparin.
Aspirin was used as control in all trials. Overall, there was no evidence that
anticoagulants were superior to
aspirin in reducing 'death or dependency' at long-term follow-up (odds ratio [OR] 1.07, 95% confidence interval [95% CI] 0.98-1.15). Compared with
aspirin,
anticoagulants were associated with a small but significant increase in the number of deaths at the end of follow-up (OR 1.10, 95% CI 1.01-1.29), equivalent to 20 more deaths (95% CI 0-30) per 1000 patients treated; a significant increased risk of symptomatic intracranial haemorrhage (OR 2.35, 95% CI 1.49-3.46); and a non-significant increased risk of 'any recurrent
stroke' during treatment (OR 1.20, 95% CI 0.99-1.46). These neutral or adverse effects outweighed a small, but significant effect on symptomatic
deep vein thrombosis (OR 1.20, 95% CI 0.07-0.58), equivalent to 10 fewer (95% CI 0-30) DVTs by 14 days per 1000 patients treated with
anticoagulants instead of
aspirin. Subgroup analysis could not identify any type, dose, or route of administration of
anticoagulants associated with net benefit, or any benefit in patients with
atrial fibrillation. Overall, the combination of UFH and
aspirin did not appear to be associated with a net advantage over
aspirin alone. A subgroup analysis showed that, compared with
aspirin, the combination of low-dose UFH and
aspirin was associated with a marginally significant reduced risk of 'any recurrent
stroke' (OR 0.75, 95% CI 0.56-1.03) and a marginally significant reduced risk of death at 14 days (OR 0.84, 95% CI 0.69-1.01), and with no clear adverse effect on death at end of follow-up (OR 0.98, 95% CI 0.85-1.12).
REVIEWER'S CONCLUSIONS: