Scientists: 40% of dementia cases could be prevented by targeting 12 risk factors
Modifying 12 risk factors over the lifecourse could delay or prevent 40% of dementia cases, according to an update to The Lancet Commission on dementia prevention, intervention, and care.
Combined, the three new risk factors are associated with 6% of all dementia cases—with an estimated 3% of cases attributable to head injuries in mid-life, 1% of cases to excessive alcohol consumption (of more than 21 units per week) in mid-life, and 2% to exposure to air pollution in later life.
The remaining risk factors are associated with 34% of all dementia cases. The factors associated with the greatest proportion of dementia cases in the population are less education in early life, hearing loss in mid-life, and smoking in later life (7%, 8%, and 5%, respectively).
Led by 28 world-leading dementia experts, the report builds on the 9 risk factors identified in the 2017 Lancet Commission, and provides an up-to-date analysis of the best evidence on the prevention of dementia. The new report calls for nations and individuals to be ambitious about preventing dementia and lays out a set of policies and lifestyle changes to help prevent dementia.
To address dementia risk, the authors call for 9 ambitious recommendations to be undertaken by policymakers and by individuals:
- Aim to maintain systolic blood pressure of 130 mm Hg or less in midlife from around age 40 years.
- Encourage use of hearing aids for hearing loss and reduce hearing loss by protecting ears from high noise levels.
- Reduce exposure to air pollution and second-hand tobacco smoke.
- Prevent head injury (particularly by targeting high risk occupations and transport)
- Prevent alcohol misuse and limit drinking to less than 21 units per week.
- Stop smoking uptake and support individuals to stop smoking (which the authors stress is beneficial at any age).
- Provide all children with primary and secondary education.
- Lead an active life into mid, and possibly later life.
- Reduce obesity and diabetes.
The authors note that the modeling for their prevention estimates globally and in LMICs assumes that there is a causal relationship between risk factors and dementia, but were careful to only include risk factors with strong evidence for a causal link.