Melbourne (LabNews Media LLC) – Low-dose aspirin was associated with a 70 percent lower risk of dementia among older people with a particular genetic profile, a new Monash University analysis has found. The research, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, raises the possibility of a more personalised approach to dementia prevention.
Background: The ASPREE Trial
The study analysed genetic data from the landmark ASPREE Trial (Aspirin in Reducing Events in the Elderly), screening genetic scores in more than 13,500 individuals to investigate whether a person’s genes influenced aspirin’s effect on reducing dementia risk. Previous trials had found that aspirin did not prevent dementia when all participants were considered together.
The strongest finding in the new analysis was linked to genetics that influence platelet count. While scientists have previously identified a link between platelet activation and aggregation and dementia, the role of a person’s overall platelet count had been less clear.
Key Findings
Researchers ranked participants according to their platelet-related genetic score. Among participants in the highest 20 percent for a platelet count genetic score:
· 1 percent of those taking aspirin developed dementia, compared with 3.3 percent of those receiving placebo – representing about a 70 percent lower relative risk associated with aspirin use.
· However, aspirin also increased the risk of serious bleeding in this group: major bleeding occurred in 4.4 percent of those taking aspirin, compared with 2.1 percent receiving placebo.
Expert Commentary
Lead author Dr Peter Fransquet, Research Fellow at Monash’s School of Public Health and Preventive Medicine, said the findings could open the door to a more personalised approach to dementia prevention.
„Previous trials found aspirin didn’t prevent dementia when everyone was considered together,“ Dr Fransquet said. „Our findings suggest there may be more to the story. In people with this particular genetic profile, we saw substantially fewer cases of dementia among those taking aspirin. It raises the possibility that genetics could one day help us identify who may benefit from a preventive treatment, rather than taking a one-size-fits-all approach.“
„What’s particularly interesting is that the signal wasn’t linked to the established genetic risk factors for Alzheimer’s disease and dementia,“ Dr Fransquet added. „Instead, it’s pointing us towards platelet biology and gives us a new avenue to investigate. We now need to confirm the finding in other studies and ultimately test it in a trial designed specifically for people with this genetic profile.“
Clinical Implications and Cautions
Dr Fransquet emphasised that people should not start taking aspirin to prevent dementia on the basis of this study without consulting their doctor, particularly given the increased risk of serious bleeding.
„If it holds up, the fact that aspirin is already cheap and widely available could make personalised dementia prevention a real possibility,“ he said.
Context: Dementia in Australia
Dementia Australia estimates 446,500 Australians are living with dementia in 2026. It projects this will rise to more than one million by 2065.
About the Study
The study, titled „Platelet count polygenic scores may modify the effect of aspirin in primary prevention of dementia,“ was authored by Dr Peter Fransquet and colleagues at Monash University. It was published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association on 24 September 2026.
DOI: https://doi.org/10.1002/alz.71817
