A comprehensive report by the 2024 Lancet Commission on dementia prevention, intervention, and care reveals that nearly half of all dementia cases could potentially be prevented or delayed by addressing 14 modifiable risk factors throughout life. The study, presented at the Alzheimer’s Association International Conference, adds high cholesterol and vision loss to the list of known risk factors, offering new avenues for prevention and management of this devastating condition.
Expanding Our Understanding of Dementia Risk
The report builds on previous work by the Lancet Commission, which had identified 12 modifiable risk factors for dementia. The two newly added factors – high low-density lipoprotein (LDL) cholesterol in midlife and untreated vision loss in later life – are associated with 9% of all dementia cases. Specifically, high LDL cholesterol accounts for an estimated 7% of cases, while vision loss contributes to 2%.
These new findings join the previously identified risk factors, which include lower levels of education, hearing impairment, high blood pressure, smoking, obesity, depression, physical inactivity, diabetes, excessive alcohol consumption, traumatic brain injury, air pollution, and social isolation.
Professor Gill Livingston from University College London, the lead author of the report, emphasizes the importance of early action: “Our new report reveals that there is much more that can and should be done to reduce the risk of dementia. It’s never too early or too late to take action, with opportunities to make an impact at any stage of life.”
A Life-Course Approach to Dementia Prevention
The Commission outlines 13 recommendations for governments and individuals to reduce dementia risk throughout life. These include providing quality education for all children, making hearing aids widely available, treating high LDL cholesterol from around age 40, screening and treating vision impairment, effectively managing depression, and reducing exposure to air pollution.
The report also stresses the importance of supportive community environments to increase social contact, as social isolation in later life is associated with 5% of dementia cases. Additionally, the authors call for measures to reduce smoking, such as price control and raising the minimum age of purchase.
Dr. Cleusa Ferri from Universidade Federal de Sao Paulo highlights the global implications: “Given the much higher burden of dementia risk factors in low- and middle-income countries with the expected rise in dementia over the next few decades from rapid population aging and increased rates of high blood pressure, diabetes, and obesity, we need urgent policy-based preventative approaches that will have huge potential benefits far in excess of the costs.”
Why it matters: With the number of people living with dementia expected to almost triple by 2050, rising from 57 million in 2019 to 153 million, understanding and addressing these risk factors is crucial. The potential to prevent or delay nearly half of dementia cases offers hope for individuals, families, and healthcare systems worldwide.
The report’s findings have significant economic implications as well. A separate study published alongside the Commission modeled the economic impact of implementing some of these recommendations in England. The results suggest that population-level interventions targeting excess alcohol use, brain injury, air pollution, smoking, obesity, and high blood pressure could achieve cost savings of more than £4 billion and over 70,000 quality-adjusted life-year gains.
However, the authors note that while their prevention estimates assume a causal relationship between risk factors and dementia, some associations may only be partly causal. They also emphasize that risk modification affects the population and does not guarantee that any individual will avoid dementia.
Looking ahead, the Commission calls for more support for people living with dementia and their families, including the provision of activity interventions and multi-component coping strategies for caregivers. They also highlight the need for more research and expanded transparency about the short and long-term effects of emerging treatments, such as Anti-amyloid β antibodies for Alzheimer’s disease.
As our understanding of dementia risk factors grows, so does the potential for prevention and better management of this complex condition. The challenge now lies in translating these findings into effective policies and interventions that can be implemented across diverse populations and healthcare systems worldwide.
