Lifestyle Habits Linked to Risk of Getting Alzheimer's, New Research Reveals
Reducing Alzheimer's Risk
Preventive measures earlier in life may reduce cognitive decline in later years. Social activity, increased education, exercise, and fruit and vegetable juices may help us maintain our brains.
A series of new research studies, examining topics including level of social activity, heart disease risk factors, education, consumption of fruit and vegetable juices, exercise, and alcohol intake, add to the growing body of scientific evidence that lifestyle habits are closely linked to risk of Alzheimer's disease and dementia, according to reports presented today at the first Alzheimer's Association's International Conference on the Prevention of Dementia in Washington.
"These studies suggest that we can maintain a healthy brain and perhaps reduce our risk for Alzheimer's disease by living a healthful lifestyle, in particular staying socially involved, remaining mentally active, improving our diets and exercising," said Ron Petersen, M.D., Ph.D., director of the Mayo Clinic Alzheimer's Disease Center (Rochester, MN) and member of the Alzheimer's Association's Medical and Scientific Advisory Council.
Decreasing social activity is associated with increased risk of dementia
Lack of community involvement and infrequent contact with friends and family in later life may increase one's risk for dementia, according to the results of a community-based study of elderly men reported at the Alzheimer's Association's Prevention Conference. Previously published reports suggested that having satisfying social relationships and participating in mentally stimulating activities with others are associated with a reduced risk of cognitive decline and dementia.
Jane Saczynski, Ph.D., of the National Institute on Aging, and colleagues presented data from 2,513 elderly Japanese American men followed since 1965 as part of the Honolulu-Asia Aging Study. Participants' social engagement was measured at mid-life and late-life, an average of 28 years and 5 years prior to cognitive testing, respectively.
Saczynski found that subjects with decreased social activity from mid- to late-life had a statistically significant increase in risk of dementia. When the men's mid- and late-life levels of social engagement were examined separately, mid-life social engagement alone was not associated with the risk of dementia. However, lower social engagement in late-life was associated with a significantly increased risk for dementia.
"Our findings suggest that interventions in late life need to consider that the dementing process may already be modifying social engagement," said Saczynski.
Twins study reveals several modifiable risk factors for dementia
In another study reported at the conference, Margaret Gatz, Ph.D., of the University of Southern California and Karolinska Institute in Stockholm, Sweden, and colleagues evaluated participants in the Study of Dementia in Swedish Twins, which followed more than 100 pairs of identical twins from the Swedish Twin Registry in which one twin had dementia and the other did not.
The researchers found that no single risk factor could explain in all cases why one twin would become demented or why the twin sibling would not. However, they did discover several patterns. The twin with dementia was more likely to have had a stroke, periodontal disease earlier in life (an index of exposure to inflammation), and fewer years of education.
"While genetic factors are significant in explaining why some people develop dementia and others do not, our research suggests that there are certain risk factors over which an individual may be able to exert some influence earlier in his or her life," Gatz said.
Fruit and vegetable juices may reduce risk for Alzheimer's disease
Amy Borenstein, Ph.D., M.P.H., of the University of South Florida's College of Public Health, and colleagues presented research suggesting that antioxidants abundant in fruit and vegetable juices may play an important role in reducing the risk of Alzheimer's disease.
The researchers investigated whether higher consumption of fruit and vegetable juices would lower the risk of Alzheimer's disease. They studied more than 1,800 older Japanese American men and women from the Kame Project in Seattle, in which participants were dementia-free at the onset of the study and were followed for up to nine years.
Borenstein and her colleagues found that participants who drank fruit or vegetable juices at least three times per week had a 75 percent reduced risk of developing Alzheimer's disease compared with those who drank these juices less than once per week. By comparison, there was no apparent dementia-related benefit from dietary or supplemental vitamin E, C or beta-carotene intake. Dietary consumption was determined using a food frequency questionnaire given at the beginning of the study.
"These findings suggest that something as simple as incorporating more fruit and vegetable juices into our diet may have a significant impact on our brain health," Borenstein said.
Exercise and moderate alcohol consumption may boost brain health
In a fourth study presented at the conference, researchers reported that simple lifestyle modifications, such as exercise and moderate alcohol consumption, may influence cognitive and memory abilities later in life.
Mark Sager, M.D., professor of Medicine at the University of Wisconsin-Madison Medical School, and colleagues studied nearly 500 adult children of persons with Alzheimer's participating in the Wisconsin Registry for Alzheimer's Prevention (WRAP). The goal of the longitudinal study is to characterize early cognitive and neurobiological changes in pre-clinical Alzheimer's disease and identify health and lifestyle variables that influence the course of the disease. Participants, ages 40-65, underwent extensive neuropsychological testing, genotyping and health assessments as part of the study.
Baseline data analyses indicated that higher levels of homocysteine, an amino acid implicated in the development of dementia, were associated with lower verbal memory scores. Researchers also found that lifestyle variables such as exercise and moderate alcohol consumption were associated with better performance on several cognitive measures.
"These findings contribute to the growing body of evidence that health and lifestyle variables in middle age may be associated with the subsequent risk of developing Alzheimer's in later life," said Sager. "They also suggest that simple lifestyle modifications may influence the prevalence of Alzheimer's in the future."
About the Alzheimer's Association
The Alzheimer's Association, the world leader in Alzheimer research and support, is the first and largest voluntary health organization dedicated to finding prevention methods, treatments and an eventual cure for Alzheimer's. For 25 years, the donor-supported, not-for-profit Alzheimer's Association has provided reliable information and care consultation; created supportive services for families; increased funding for dementia research; and influenced public policy changes. Washington, D.C.
The Alzheimer's Association's vision is a world without Alzheimer's and its dual mission is to eliminate Alzheimer's disease through the advancement of research and to enhance care and support for individuals, their families and caregivers. For more information, visit http://www.alz.org