Nutritionists have long endorsed fish as part of a heart-healthy diet, and now some studies suggest that an omega-3 fatty acid found in the oil of certain fish, algae and human breast milk may also benefit the brain by lowering the risk of Alzheimer’s disease.
In order to test whether docosahexaenoic acid (DHA), an omega-3 fatty acid, can impact the progression of Alzheimer’s disease, researchers at the University of California, Davis, supported by the National Institute on Aging (NIA), part of the National Institutes of Health, will evaluate DHA in a clinical trial, the gold standard for medical research.
The UC Davis effort is part of a nationwide consortium of leading Alzheimer’s disease researchers coordinated by the UC San Diego. The trial, which includes 52 sites across the United States, will recruit 400 participants age 50 and older with mild to moderate Alzheimer’s disease.
Joseph Quinn, associate professor of neurology at Oregon Health and Science University, is directing the national study. Charles DeCarli, director of the UC Davis Alzheimer’s Disease Center and professor of neurology with the UC Davis School of Medicine, is leading the local effort.
Researchers will primarily evaluate whether taking DHA over many months reduces the rates of both cognitive and functional decline in people with mild to moderate Alzheimer’s. During the 18-month clinical trial, investigators will measure progress of the disease using standard tests for functional and cognitive change.
‘Evidence so far from various research studies on the effects of omega-3 fatty acids on Alzheimer’s disease merits further evaluation in a rigorous clinical trial,’ said DeCarli. ‘Our hope is that we may find out that DHA plays a role in slowing the pace of this destructive disease.’
In recent European studies and the Framingham Heart Study, scientists reported that people with the highest blood levels of DHA were about half as likely to develop dementia as those with lower levels.
‘Study volunteers will be critical to helping us find out if DHA can make an impact on the disease process,’ said DeCarli.
For the clinical trial, the Martek Biosciences Corporation of Columbia, Md., will donate a pure form of DHA made from algae devoid of fish-related contaminants. Participants will receive either two grams of DHA per day or an inactive placebo pill. About 60 percent of participants will receive DHA and 40 percent will get the placebo. Doctors and nurses at the 52 research clinic sites will monitor participants with regular visits throughout the trial. To ensure unbiased results, neither the researchers conducting the trial nor the participants will know who is getting DHA and who is receiving the placebo.
In addition to monitoring disease progression through cognitive tests, researchers will also evaluate whether taking DHA supplements has a positive effect on physical and biological markers of Alzheimer’s, such as brain atrophy and proteins in blood and spinal fluid.
The NIA leads the federal effort that supports and conducts research on aging and the medical, social and behavioral issues of older people, including Alzheimer’s disease and age-related cognitive decline. For more information, visit the NIA’s Alzheimer’s Disease Education and Referral Center at www.nia.nih.gov/alzheimers, or call 1-800-438-4380.
For general information on research and aging, go to www.nia.nih.gov. For information about NIH and its programs, visit www.nih.gov. The UC Davis Alzheimer’s Disease Center conducts research, provides education programs and advocates for policy changes related to the diagnosis, treatment and management of Alzheimer’s disease and related dementias. For more information, visit http://alzheimer.ucdavis.edu.
