Key messages:
- Nearly half of dementia cases could be prevented or delayed by addressing 14 risk factors.
- Reducing the risk of dementia increases years of healthy life and reduces the time people who develop dementia spend in ill health.
- It is never too early or too late to reduce dementia risk.
Due to the rapidly aging global population, the number of people living with dementia is projected to nearly triple by 2050, increasing from 57 million in 2019 to 153 million. Rising life expectancy is contributing to the rise in dementia in low-income countries. The global health and social costs associated with dementia are estimated to exceed $1 trillion annually, emphasizing the need to identify and implement prevention strategies.
The 2024 report of the Lancet Commission on dementia highlights the advances since the 2020 report on modifiable risk factors and preventive interventions, new biomarkers and diagnostic definitions for Alzheimer’s disease, and new treatments.
The Lancet Commission estimates that 45% of global dementia can be attributed to 14 factors: less education, hearing loss, vision loss, hypertension, smoking, obesity, depression, physical inactivity, diabetes, excessive alcohol consumption, traumatic brain injury, air pollution, social isolation, and high LDL cholesterol. The report indicates nearly half of dementias could theoretically be prevented or delayed by eliminating these 14 risk factors.
Although addressing risk factors at an early age is preferable, there are also benefits to tackling risk throughout life. Further evidence suggests that these changes are often cost-saving and risk can be modified even in people with higher genetic risk of dementia.
The report recommends specific actions aimed at individuals and governments to help guard against dementia, including:
- Ensuring quality education is available for all and remaining cognitively active throughout life
- Preventing and treating hearing loss, vision loss, and depression
- Participating in sports and exercise
- Using head protection in contact sports and on bicycles
- Reducing cigarette smoking and making smoking cessation advice accessible
- Reducing cardiovascular risk factors (i.e., high LDL cholesterol, diabetes, obesity, hypertension)
- Reducing alcohol consumption
- Providing supportive community environments to increase social contact
- Improving air quality
For people with dementia, interventions after diagnosis can help maximize physical health, improve quality of life, and reduce hospitalizations. Interventions should be individualized, consider the person’s life circumstances, and include family and other caregivers.
The advances in understanding protection and risk and in pharmacological and nonpharmacological interventions for people with dementia mean that now, more than ever, dementia can be prevented, diagnosed, and treated, improving life for individuals, families, and society.