Background: The 2020 Lancet Commission on dementia prevention, intervention and care estimated that up to 40% of dementia cases could be prevented by tackling 12 potentially modifiable risk factors, namely less education, hearing loss, hypertension, physical inactivity, diabetes, social isolation, excessive alcohol consumption, air pollution, smoking, obesity, traumatic brain injury, depression. As more evidence on risk factors emerges, the Lancet standing commission on dementia met to update evidence on established dementia risk factors and to consider the evidence for other risk factors.
Method: We used a lifecourse approach to understand how to reduce risk or prevent dementia, as many risks operate at different timepoints in the lifespan. We considered evidence for when in the lifecourse a risk factor was relevant to development of dementia as well as the size of the effect and strength of the evidence. Our interdisciplinary, international, multicultural group of experts adopted a triangulation framework, prioritising systematic reviews and meta-analyses, performing new meta-analyses where needed and debated and agreed on the best available evidence and its consistency. We considered whether there was evidence of disparities in impact of risk factors based on demographic characteristics, particularly ethnicity and socioeconomic status.
Result: Evidence for two new risk factors was considered strong enough to include this in our lifecourse model. We will present evidence for incorporation of these risk factors, including strength of evidence and potential mechanisms. We will also discuss risk factors for which evidence was not strong enough.
Conclusion: As more evidence about risk factors emerges we can increase our understanding of how dementia develops and how to potentially prevent it. Understanding the landscape of dementia prevention research is also helpful to appreciate where further evidence is needed and what form of evidence would be most helpful in advancing our understanding.
© 2024 The Alzheimer's Association. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.