Alzheimer's cases may nearly triple by 2050, new study says

More than 13 million people in the United States could have Alzheimer's disease by the year 2050 -- nearly three times higher than the number believed to have Alzheimer's today, according to a new study.

The projected increase is largely due to the aging of the population and increased life expectancy, according to the research being published Tuesday in the journal Archives of Neurology. Alzheimer's is a disease that primarily afflicts those over 75.

The finding "reinforces the observation that Alzheimer's disease will become an increasingly frequent disease and a major challenge to society and to public health," said Dr. Jeffrey Cummings, director of the University of California, Los Angeles' Alzheimer's disease center.

The projection was made by scientists at Rush-Presbyterian-St. Luke's Medical Center in Chicago and the U.S. Centers for Disease Control and Prevention.

The research underscores the need for better therapies, preferably ones that will prevent the disease from occurring in the first place, said Dr. Denis Evans, senior author of the study and professor of medicine at Rush-Presbyterian-St. Luke's Medical Center.

"Nobody wants to be around if we get 13.2 million people with Alzheimer's," Evans said. "We want to take good care of people who have the disease but recognize that we have to do something about disease prevention."

To obtain their estimates, the scientists first assessed the incidence of Alzheimer's cases in nearly 4,000 Chicago residents age 65 or older. They then extrapolated their findings to the U.S. population at large for different time periods in the future.

According to the scientists' calculations, the number of Americans with Alzheimer's disease is predicted to increase from 4.5 million in 2000 to 5.1 million in 2010, 5.7 million in 2020, 7.7 million in 2030 and 11 million in 2040. By 2050, the number is projected to stand at 13.2 million.

Scientists are pursuing various strategies to fight off the degenerative brain disease, which is the most common form of dementia. Current treatments include drugs that help replace supplies of a key brain chemical, acetylcholine, and therapies with the antioxidant vitamin E.

New drugs under investigation would fight the accumulation in the brain of protein plaques, a hallmark of the disease.

Strategies under investigation that may lower risk of the disease include eating fish, keeping the mind active, avoiding saturated fats and taking cholesterol-lowering drugs known as statins.