Independent Panel Finds Insufficient Evidence to Support Preventive Measures for Alzheimer's Disease
Many preventive measures for cognitive decline and for preventing Alzheimer's disease—mental stimulation, exercise, and a variety of dietary supplements—have been studied over the years. However, an independent panel convened by the National Institutes of Health has determined that the value of these strategies for delaying the onset and/or reducing the severity of decline or disease hasn't been demonstrated in rigorous studies.
Balintfy: Experts explain Alzheimer's disease as an irreversible, age-related brain disorder that develops over many years, the hallmark in early stages being memory loss.
Buckholtz: The major risk factor for Alzheimerís disease is still aging.
Balintfy: Dr. Neil Buckholtz is chief of the Dementias of Aging Branch in the Neuroscience and Neuropsychology of Aging Program at the National Institute on Aging.
Buckholtz: Itís estimated that there are up to five million people in the United States currently with Alzheimer's disease, and the projections are that by mid-century, there will be anywhere from 12 to 14 million people in the U.S.
Balintfy: Dr. Buckholtz was the planning committee chair for a State-of-the-Science Conference called "Preventing Alzheimer's Disease and Cognitive Decline." He and the scientists at the conference know how feared and tragic Alzheimer's disease is, in part because there is no cure.
Buckholtz: The current treatments provide some symptomatic benefit for a small period of time, maybe a couple years, but there are no treatments that are currently available that will delay the progression of the disease.
Balintfy: So a major focus is prevention.
Buckholtz: There are things put forward all the time which are purported to prevent Alzheimer's disease, but the question was what is the actual scientific evidence for any of these things for preventing Alzheimer's disease or age-related cognitive decline.
Balintfy: Dr. Buckholtz explains that the panelists at the conference evaluated various reports, literature, and studies on Alzheimer's disease.
Buckholtz: And what they found was that there is no evidence that reaches what they call a high or medium level of evidence, but there are some things that are suggestive of associations. And the major recommendation was that more research needs to be done to firm up these kinds of associations.
Balintfy: These associations are examples of the classic chicken or the egg quandary, explains one panelist: An association only tells whether things are related, not that one causes the other.
Buckholtz: So, for example, Alzheimer's disease, there's some suggestion that the risk of Alzheimer's disease goes up with diabetes, with high cholesterol at mid-life, with depression, and may go down with omega-3 fatty acids, fruits and vegetables, higher education, increased physical activity. But the data are not really pinned down sufficiently to make—actually make that recommendation.
Balintfy: But Dr. Buckholtz adds that while the panel has made a variety of recommendations to shape the future research agenda and fill identified gaps in research, NIH is already doing a number of these studies to look at some of these factors in clinical trials.
Buckholtz: And a number of epidemiological studies are looking at some of these other factors, such as fruits and vegetables, omega-3 fatty acids, fish consumption, those sorts of things. So, these are—some of these are ongoing; some of these things need to be done in a much more rigorous fashion. But I think these recommendations were quite good in suggesting how to go forward with the research agenda.
Balintfy: For more about the State-of-the-Science Conference called "Preventing Alzheimer's Disease and Cognitive Decline" visit the Web site consensus.nih.gov. And learn more about Alzheimerís disease at www.nia.nih.gov. This is Joe Balintfy, National Institutes of Health, Bethesda, Maryland.
About This Audio Report
Reporter: Joe Balintfy
Sound Bite: Dr. Neil Buckholtz
Topic: Alzheimer's disease, Alzheimer, cognitive decline, age-related, brain disorder, memory loss, risk, treatment, prevention, research, Preventing Alzheimerís Disease and Cognitive Decline
NIH Consensus Development Program