The rationale for using aspirin to prevent mild cognitive impairment and dementia seems compelling. Disorders of cognition affect 10-15% of the general population over 65.1 2 Cerebrovascular disease plays a pivotal role in the development and progression of mild cognitive impairment and dementia.1 2 Aspirin prevents first ever stroke in apparently healthy asymptomatic women,3 and it also prevents first ever and recurrent stroke in high risk populations.4 Thus, by preventing cerebral ischaemia, aspirin would be expected to reduce the burden of cognitive loss to individuals and society. Observational studies have shown an association between the use of aspirin and reduced odds of cognitive impairment,5 6 but randomised controlled trials have been lacking until recently.

In the linked study (doi: 10.1136/bmj.a1198), Price and colleagues report cognitive outcomes from the aspirin for asymptomatic atherosclerosis (AAA) trial, which randomised 3350 middle aged …