Key Takeaway:
- Genetic profile may matter: Low-dose aspirin was associated with a 70% lower relative dementia risk in older adults with a specific genetic profile.
- Bleeding risk increased: Major bleeding affected 4.4% of aspirin users in the subgroup, compared with 2.1% receiving a placebo.
- More research is needed: The findings are preliminary; people should not take aspirin for dementia prevention without medical advice.
Aspirin and dementia risk may be connected through genetics, according to researchers at Monash University. They found that low-dose aspirin was associated with a 70% lower relative risk of dementia among older adults with a specific genetic profile. The same group also faced an increased risk of serious bleeding, and the researchers stress that the findings are preliminary.
Researchers Identify a Genetic Link to Aspirin Benefits
The analysis, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, examined data from 13,541 participants in the ASPREE trial, which investigated aspirin’s effects on health outcomes in older adults.
Researchers examined thousands of genetic risk scores to determine whether genetic differences influenced aspirin’s association with dementia and major bleeding. The strongest finding involved genetic variations linked to platelet count, which may influence how aspirin affects clotting-related blood cells.
Among participants in the highest 20% for a platelet-count genetic score, 1% of those assigned aspirin developed dementia, compared with 3.3% of those receiving a placebo. This represented approximately a 70% lower relative risk in the aspirin group.
However, the findings do not establish that aspirin prevents dementia in this group. The researchers described the results as preliminary and said further studies are necessary to confirm whether the genetic profile reliably identifies people who may benefit.
Peter Fransquet, the study’s lead author and a research fellow at Monash University’s School of Public Health and Preventive Medicine, said earlier trials found no overall dementia-prevention benefit when researchers considered participants collectively.
“Our findings suggest there may be more to the story,” Fransquet said in a statement released by the university.
Potential Benefits Come With a Serious Bleeding Risk
The possible reduction in dementia risk came with a significant safety concern. Among participants with the relevant genetic profile, major bleeding occurred in 4.4% of those assigned aspirin, compared with 2.1% of those receiving a placebo.
The findings suggest that the same genetic characteristics associated with a potentially lower dementia risk may also identify people who face greater harm from aspirin. Researchers said this trade-off needs careful evaluation before the results can inform clinical decisions.
Aspirin reduces platelet activity, making blood less likely to form clots. While this effect can help prevent certain cardiovascular events in appropriately selected patients, it can also increase the risk of gastrointestinal bleeding and other serious complications.
The study did not establish a genetic test that doctors can currently use to determine who should take aspirin to prevent dementia. The findings instead point to platelet biology as an area that warrants further investigation.
Scientists Call for Further Research Before Treatment Changes
The results could eventually support a more personalized approach to dementia prevention, in which genetic information helps researchers understand why a medication may affect different groups differently. However, the study’s findings need independent confirmation before such an approach becomes part of routine care.
Fransquet said the research team must confirm the association in other studies and conduct a clinical trial specifically designed for people with the identified genetic profile.
“People shouldn’t start taking aspirin to prevent dementia based on this study without consulting with their doctor, particularly given the increased risk of serious bleeding,” Fransquet said.
The research also highlights the limitations of applying a single prevention strategy to everyone. Previous trials have not shown that low-dose aspirin prevents dementia across the general older population, and the new analysis does not overturn that conclusion.
Researchers say further investigation may clarify whether genetic differences can help identify people for whom the potential benefits outweigh the risks. Until then, aspirin should be used according to established medical guidance rather than as a self-directed dementia prevention measure.
