A clinical trial looking at use of daily aspirin in healthy people aged 70 or over, has suggested that there is no overall benefit, when considering risk of death, dementia or physical disability.
The trial involved 19,000 healthy individuals aged 70 years or older, who were asked to take either a low-dose (100mg) aspirin tablet or a placebo (dummy) tablet daily for 5 years. The numbers of people who died or were diagnosed with dementia or a physical disability were similar in the two groups. Aspirin also did not appear to reduce the number of people having a heart attack or stroke as has been seen in studies of other groups of people (such as those with a higher than average risk of these events).
A rare side effect of aspirin is internal bleeding, which can be serious. Such bleeding can also occur in people not taking aspirin, and is more common in elderly people. As has been seen in other studies, this trial showed that those people taking aspirin had a slightly greater risk of bleeding. Individuals who have an increased risk of internal bleeding are not eligible for the Add-Aspirin trial, and participants and data from the trial are monitored closely in relation to this. Elderly participants will not be prescribed the higher dose of aspirin, and may be prescribed an additional medication (proton pump inhibitor) to reduce the risk of bleeding.
The group of people taking aspirin in this new study were also slightly more likely to die from cancer. This differs from a number of other studies which have suggested a benefit of aspirin in terms of cancer risk. Since cancer can take a number of years to develop, a benefit may not be seen until after 5 years, and so results from this trial (in which people were followed up for less than 5 years) should be interpreted with caution.
Participants in the Add-Aspirin trial have had treatment for a previous cancer - we expect any benefits of aspirin (in terms of cancer prevention) to be greatest in these individuals, because of the risk of the cancer returning. This has not yet been confirmed and will be looked at in the trial. As such, we do not believe the results of this recent study in healthy individuals changes the Add-Aspirin trial.