The risks and benefits of prophylactic aspirin in vascular disease and cancer

Substantial evidence from randomized trials confirms benefit from aspirin in the secondary reduction of vascular disease but there is debate about its use in primary prevention. More recently, evidence from long-term follow up and other studies indicates a reduction in cancer by aspirin. The undesirable effects of aspirin include gastrointestinal bleeding and, rarely, cerebral bleeding. However, deaths from gastrointestinal bleeding attributable to aspirin appear not to be increased, suggesting that the bleeds provoked by aspirin are not the most serious. There is also suggestive, but limited, evidence that cerebral bleeds may occur only in the presence of uncontrolled hypertension. It is important that in considering the risk–benefit balance of aspirin prophylaxis from a public health point of view, reductions in vascular disease events and in cancer are considered together. Furthermore, low-dose aspirin is prophylaxis and not treatment, and so advice about aspirin should be given to subjects within the context of a healthy lifestyle to enable them to make informed decisions about the protection of their own health.