Evidence insufficient on relationship of modifiable factors with risk of Alzheimer's disease

The available evidence is insufficient to draw firm conclusions about the association of modifiable factors and risk of Alzheimer's disease (AD), according to a report posted online today that will appear in the September issue of Archives of Neurology.

Estimates suggest that up to 5.3 million people in this country may have AD, and this number will likely increase as grow older. In fact, "age is currently the strongest known risk factor for AD," write the authors. Variation in the (APOE) gene is also associated with the risk of developing AD. However, existing research to ascertain other for the condition has been less conclusive.

From April 26 to 28, 2010, the National Institutes of Health convened a State-of-the-Science Conference to examine studies of potential AD risk factors and possible preventive measures. The conference evaluated existing English-language research found in MEDLINE and the Cochrane Database of Systematic Reviews from 1984 through October 27, 2009, as well as a formal evidence report. Topics considered were nutritional supplements and dietary factors, physical activity, other chronic conditions (diabetes, high cholesterol, ), substance use (cigarettes, alcohol), and cognitive engagement. Panelists weighed the level of evidence for each risk factor (low, moderate or high) and rated studies accordingly (low for observational studies vs. high for ).

Martha L. Daviglus, M.D., Ph.D., from Northwestern University Feinberg School of Medicine, Chicago, and colleagues summarized the panel's findings. The group determined "that currently there is no evidence of even moderate scientific quality supporting the association of any modifiable factor with reduced risk of or AD." While some studies appeared to show an increase or reduction of AD risk or progression, they were not strong enough to draw firm conclusions. The authors call for large-scale, long-term, population-based studies and clinical trials to answer these questions. "It is hoped that the panel's report will instigate rigorous high-quality research that can provide conclusive evidence on this issue," they write. "Until more conclusive results are available, individuals should continue to aim for a physically and mentally active and healthy lifestyle and prevention of the well-known major risk factors for chronic diseases."

More information: Arch Neurol. 2011;doi:10.1001/archneurol.2011/100

add to favorites email to friend print save as pdf

Related Stories

Engineered mice provide insight into Alzheimer's disease

Jan 17, 2008

One factor that determines how at risk an individual is of developing late-onset Alzheimer disease (AD) is the version of the APOE gene that they carry — those carrying the gene that enables them to make the apoE4 form ...

Recommended for you

Are medications' adverse cognitive effects reversible?

Jan 26, 2015

Whether the adverse cognitive effects of medications can be reversed is of significant importance to an aging population, their caregivers and their families, as well as to an overburdened health care system.

Higher dementia risk linked to more use of common drugs

Jan 26, 2015

A large study links a significantly increased risk for developing dementia, including Alzheimer's disease, to taking commonly used medications with anticholinergic effects at higher doses or for a longer ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.