Middle-aged sons and daughters of people with Alzheimer's disease may be able to reduce their risk of getting the disorder through lifestyle measures such as exercise, avoiding gum disease, moderate alcohol consumption and drinking fruit and vegetable juice, according to new research.
Taken as a whole, the research suggests that even though family history may predispose a person to developing Alzheimer's, various behaviors -- if started early enough in life -- may help preserve cognitive function and delay the onset of the disease.
"The best time to intervene is at birth," said Mark Sager, a professor of medicine at the University of Wisconsin at Madison. "What we are hoping is that 55 is not too late."
The lifestyle measures, many of which are also good for the heart, were presented in several studies in Washington yesterday at the Alzheimer's Association's first International Conference on the Prevention of Dementia.
The findings come amid growing concern about a looming surge in Alzheimer's cases in the years ahead as the U.S. population ages. Nearly 5 million people have the disease, and with the vanguard of the baby boom generation turning 60 this year, the number of cases is expected to increase 70 percent by 2020.
Sager presented findings from the ongoing Wisconsin Registry for Alzheimer's Prevention, a study of nearly 500 middle-aged children of Wisconsin residents who had Alzheimer's disease. The children, who now have an average age of 53, have been followed for five years.
So far, moderate drinkers and exercisers have performed better on cognitive tests than non-drinkers and sedentary members of the study.
"It suggests that exercise may be protective," said Sager, director of the Wisconsin Alzheimer's Institute.
Moderate drinkers also did better on verbal fluency tests than non-drinkers, he said.
Sager said he would not recommend that people at risk for the disease begin drinking, although he would not discourage anyone who can handle a glass or two of wine a day from drinking. "It's all moderation," he said.
However, a second study suggests that fruit and vegetable juices may be just as effective as alcohol. It looked at juice consumption in 1,800 older Japanese Americans in Seattle. Those who drank at least three glasses of juice a week had 75 percent less risk of developing dementia than those who drank less than one glass a week.
"This is the first study to try to get at polyphenol exposure," said Amy Borenstein of the University of South Florida College of Public Health. Polyphenols, also known as flavonoids, are substances found in plants that have antioxidant properties. Borenstein said polyphenols generally are found in higher concentrations in juices than in whole fruits and vegetables.
A third study followed 109 pairs of identical twins in Sweden to find any lifestyle factors associated with developing dementia.
"Studying twins allows us to isolate genetic and non-genetic factors," said lead author Margaret Gatz of the University of Southern California and Karolinska Institute in Stockholm.
The study found that twins who had suffered a stroke were six times more likely to develop dementia; those who had periodontal disease earlier in life were four times more likely; and those with lower levels of education were 1.6 times more likely.
Gum disease is considered a marker for inflammation, which is believed to play a role in brain cell death. Higher levels of education as well as staying mentally active may help people develop more reserve brain power.
"Good brain health in old age reflects influences that begin much earlier in life," Gatz said.