Prevention Strategies for Cognitive Decline, Dementia Unclear

The risk of dementia and cognitive impairment naturally increase with age. To prevent this mental deterioration, many individuals use diet, exercise, games, and supplements to ensure that the brain does not develop these conditions.

However, it is increasingly difficult for healthcare providers and policy makers to determine which approach to preventing or reducing dementia or impairment is the most effective, according to the National Institutes on Aging (NIA). In an effort to address the difficulties of effective prevention for cognitive decline, the NIA commissioned experts to review the quality and weight of evidence for interventions.

The National Academies of Sciences, Engineering, and Medicine committee conducted an extensive scientific review to provide recommendations about public health initiatives and research priorities for dementia and cognitive impairment, according to the release.

The committee found that evidence for cognitive training, blood pressure control, and exercise, was encouraging, but inconclusive.

Based on these findings, the committee recommends providing the public with accurate information about the potential impact of these approaches while additional research is conducted, according to the NIA.

The new recommendations are based on a review by the Agency for Healthcare Research and Quality’s (AHRQ) Evidence-based Practice Center (EPC), which categorized studies by strength and quality.

“We’re all urgently seeking ways to prevent dementia and cognitive decline with age,” said Richard J. Hodes, MD, NIA director. “But we must consider the strength of evidence -- or lack thereof -- in making decisions about personal and public investments in prevention. I am grateful for the National Academies’ and AHRQ’s careful reviews, which recognize the progress research has made in beginning to answer such questions, while pointing the way for additional studies. This report will be very instructive for what we can tell the public now, as critical research continues.”

For its evidence review, the EPC analyzed studies about 13 interventions believed to prevent, slow, or delay the onset of dementia and mild cognitive impairment.

The committee found that cognitive training has potentially beneficial effects. These interventions include enhanced reasoning, memory, and speed of processing. However, the committee did not draw a conclusion about the efficacy of the different approaches, according to the report.

The authors also found encouraging, inconclusive results for managing blood pressure for patients with hypertension. The committee deliberated that blood pressure management during midlife may result in the prevention or delay of Alzheimer’s disease-like dementia.

While clinical trials did not offer significant support for blood pressure management, other studies and a better understanding of the biology of the disease suggest that controlling blood pressure has the potential to lessen the risk of dementia and cognitive decline, according to the report.

It is well understood that physical activity can elicit numerous health benefits. While the committee found that clinical trials suggest exercise may reduce the risk of dementia and cognitive impairment, it was not enough to support this intervention.

The committee concluded that health organizations should speak to the potential benefits of cognitive training, blood pressure management, and physical activity, while also acknowledging their limitations.

Since the last review in 2010, the experts said that there have been significant gains in knowledge regarding age-related cognitive issues. The committee believes that with time, the understanding will continue to increase with research.

In addition to ongoing research for the 3 interventions, the experts recommended several areas for further research, including anti-dementia therapy; diabetes and depression treatments; dietary interventions; lipid-lowering treatments; sleep quality interventions; social engagement, and vitamin supplementation, the report concluded.