Reducing Risks Could Cut Alzheimer's

Moderate lifestyle changes may seem small, but they can provide large returns in better health. Exercising and smoking cessation are among modifiable changes capable of reducing risk of Alzheimer's disease.

Just over half of all Alzheimer's disease cases may be preventable through lifestyle changes, which could prevent about three million U.S. cases each year.

Cut your risk by exercising regularly and quitting smoking.

Deborah Barnes, associate professor of psychiatry at the University of California San Francisco and Mental Health Research PI at the San Francisco Veterans Affairs Medical Center, calculated modifiable risks and their potential impact on the prevalence of Alzheimer's in the United States and worldwide.

Her research was recently presented at the Alzheimer's Association International Conference 2011 in Paris. The research also was published in Lancet Neurology.

Barnes used population attributable risks to determine the percentage of cases caused by certain risk factors. She also examined the strength of the link to each risk.

The results revealed that of 5.4 million Americans living with Alzheimer's, about 3 million of those cases could have been prevented. Worldwide about 17 million cases could be avoided through lifestyle management.

About 54 percent could be prevented in the United States. In the U.S. the leading risk factors were physical inactivity, which contributed 21 percent; depression, which increased the risk by 15 percent and smoking; which negatively impacted the Alzheimer's risk by 11 percent.

Other risk factors included mid-life hypertension, mid-life obesity, low education and diabetes. Worldwide, low education was the top contributor ay 19 percent, while only 13 percent of cases were attributed to a sedentary lifestyle at the global level.

Barnes said she was surprised that lifestyle factors such as a lack of exercise and smoking contributed a larger number of cases than risks associated with heart disease such as high blood pressure. But she said the research indicates that lifestyle changes could help dramatically reduce the number of Alzheimer's disease cases.

A 10 percent reduction in all seven factors could help prevent 1.1 million Alzheimer's cases worldwide, including 184,000 in the United States.