It has been reported that aspirin and other non-steroidal anti-inflammatory drugs (NSAID) may protect against dementia of Alzheimer's type and/or vascular dementia. However, co-morbidity and the dose of aspirin may be critical. A major indication for low-dose aspirin is prophylaxis after stroke and transient ischaemic attacks, conditions that may obscure an anti-dementia effect by the drug. Alternatively, low-dose aspirin may be insufficient if the protective effect is due to an anti-inflammatory mechanism