The Annals of Internal Medicine on December 19, 2017, published four evidence-based reviews looking at randomized controlled trials on the effectiveness interventions to prevent dementia. The reviews, conducted by the Agency for Healthcare Research and Quality's (AHRQ's) Minnesota Evidence-based Practice Center, were requested by the National Institute on Aging at the National Institutes of Health to assess the state of the science for interventions in key areas of age-related brain function.
The reports systematically examined current evidence for approaches to reduce cognitive decline, mild cognitive impairment, and Alzheimer-type dementia in four areas: cognitive training, over-the-counter supplements, pharmacological interventions, and physical activity. These reviews served as the basis for a report from the National Academies of Sciences, Engineering and Medicine (NASEM), Preventing Cognitive Decline and Dementia: A Way Forward, commissioned by NIA and released in June 2017. NIA asked NASEM's Committee on Preventing Dementia and Cognitive Impairment about possible public health messaging based on the state of the science.
That NASEM committee concluded that current evidence does not support a full public health education campaign to encourage adoption of specific interventions for the prevention of cognitive change, impairment, or Alzheimer's. However, the committee did find "encouraging although inconclusive" evidence for three specific types of interventions—cognitive training, blood pressure control for people with hypertension, and increased physical activity.
To read the Annals review articles, go to:
Physical Activity Interventions in Preventing Cognitive Decline and Alzheimer-Type Dementia
Does Cognitive Training Prevent Cognitive Decline?
In an accompanying editorial, Dr. Eric Larson of the Kaiser Permanente Washington Health Research Institute, acknowledged that the current state of evidence does not provide a "magic bullet" for dementia prevention. Looking at the NASEM report recommendations and recommendations from a July 2017 Lancet Commission report on effective dementia prevention, intervention, and care, Larson underscored at the same time that progress that has been made in our understanding of basic biology of the brain as people age. He also notes that "promising trials on dementia prevention are under way." Larson was both a member of the NASEM committee and involved in the development of the Lancet Commission report. The Larson editorial appears at:
Prevention of Late-Life Dementia: No Magic Bullet
In a related JAMA Internal Medicine editorial Dec. 18, 2017, Dr. Kristine Yaffe of the University of California San Francisco, provided a summary of the NASEM report and the Lancet-commissioned report. Yaffe notes that the two reported different recommendations, based on the different approaches to assessing the current evidence base for dementia prevention. Despite the differences, Yaffe noted, the efforts both suggest that people could be encouraged to adopt strategies that have overall health benefits, including the reduction of cardiovascular risk factors, while additional studies are being conducted to assess their direct relationship to dementia prevention. Yaffe was both a member of the NASEM committee and involved in the development of the Lancet Commission report. The JAMA editorial appears at:
Modifiable Risk Factors and Prevention of Dementia: What Is the Latest Evidence?