A groundbreaking report from the Lancet Commission on dementia prevention, intervention, and care reveals that nearly half of dementia cases worldwide could potentially be prevented or delayed by addressing modifiable risk factors throughout a person’s life. This study underscores the significant impact of lifestyle and health management on dementia risk.
The report, published in The Lancet Neurology, expands on previous research by adding two new modifiable risk factors—high cholesterol and vision loss—to the 12 already identified in the 2020 Lancet Commission report. These additional factors increase the percentage of dementia cases potentially linked to modifiable risks from 40% to nearly 50%.
Evolution of Dementia Risk Factors
The Lancet Commission’s initial report in 2017 pinpointed nine risk factors responsible for about one-third of dementia cases. By 2020, this list grew to include lower levels of education, hearing loss, hypertension, smoking, obesity, depression, physical inactivity, diabetes, excessive alcohol consumption, traumatic brain injury (TBI), air pollution, and social isolation.
The latest report adds untreated vision loss and elevated low-density lipoprotein (LDL) cholesterol as significant contributors. These two new risk factors are associated with approximately 9% of dementia cases: 7% due to high LDL cholesterol from around age 40, and 2% due to untreated vision loss later in life.
Leading Modifiable Risk Factors
Among the 14 identified risk factors, those contributing most significantly to global dementia cases include hearing impairment and high LDL cholesterol (each accounting for 7% of cases), as well as lower education levels in early life and social isolation in later life (each responsible for 5% of cases).
Recommendations for Prevention
The report outlines key recommendations for individuals and governments to mitigate dementia risk:
1. Prevent and treat hearing loss, vision loss, and depression.
2. Maintain cognitive activity throughout life.
3. Use head protection in contact sports.
4. Reduce vascular risk factors (high cholesterol, diabetes, obesity, hypertension).
5. Improve air quality.
6. Foster supportive community environments to enhance social contact.
Dr. Tara Spires-Jones, president of the British Neuroscience Association, emphasized that while the research does not directly link specific factors to dementia, it supports evidence that a healthy lifestyle—including education, social activities, exercise, cognitive engagement, and avoiding head injuries and harmful factors for heart and lung health—can bolster brain resilience and prevent dementia.
Expert Insights
Dr. Shaheen Lakhan, a neurologist and researcher, highlighted the importance of the addition of high cholesterol as a risk factor, reinforcing the link between vascular health and brain health. He noted that untreated vision loss not only affects sight but also cognitive function due to increased social isolation and reduced physical activity.
Heather M. Snyder, senior vice president of medical and scientific relations at the Alzheimer’s Association, stressed the complexity of brain health, noting that factors throughout our lives can influence dementia risk as we age. She advocates for a comprehensive approach that includes discussions on diet, exercise, heart health, hearing, and vision.
The Imperative of Prevention
Dr. Masud Husain of the University of Oxford emphasized the significance of the report’s conclusions for health policymakers. He argued that simple preventative measures, such as screening for the identified risk factors, could prevent dementia on a national scale more cost-effectively than developing high-tech treatments.
A Call to Action
Implementing the report’s recommendations requires coordinated efforts from individuals, healthcare systems, and policymakers. The potential benefits, in terms of both quality of life and economic savings, underscore the importance of this endeavor. Preventing dementia is not just a medical imperative but also an economic and humanitarian one.