- Colin Baigent (firstname.lastname@example.org), reader in clinical epidemiology1
- 1 Clinical Trial Service Unit and Epidemiological Studies Unit, Radcliffe Infirmary, Oxford OX2 6HE
- Accepted 11 May 2005
Current population screening for vascular disease is neither efficient nor effective. Peter Elwood and colleagues believe we should have a public information strategy highlighting the benefits (and risks) of aspirin for older people, but Colin Baigent argues that the evidence of benefit is not yet strong enough
An age threshold approach to aspirin prophylaxis in people without known vascular disease has two important problems. The balance of benefits and risks of aspirin in people aged 70 or over has not been clearly defined in randomised trials, and the benefits do not clearly exceed the risks in younger people without vascular disease. Consequently, it would be unwise to adopt such a policy, whatever age threshold is chosen, until we are sure that older patients will derive net benefit from it.
What studies show
Among high risk patients with known occlusive arterial disease and a greater than 3% annual risk of a vascular event (defined as non-fatal myocardial infarction, non-fatal stroke, or vascular death), the benefits of aspirin substantially outweigh the risks of bleeding. A recent meta-analysis of randomised trials of antiplatelet drugs versus control showed that for every 1000 such patients treated for a year, aspirin would be expected to prevent about 10-20 vascular events and cause one or two major gastrointestinal bleeds.1 In a wide range of high risk …