About 5.2 million people in the U.S have Alzheimer's disease, but new studies presented at the Alzheimer's Association International Conference in Copenhagen, Denmark, on July 15 showed that in recent decades, the incidence rate of Alzheimer's disease has been declining in the U.S. as well as in other developed countries.
One of the studies found that the number of individuals who were diagnosed with dementia in the U.S was 44 percent lower in recent years compared with the diagnosis rate in the late 1970s. Two other studies that looked at new cases of dementia in Germany, the UK, Sweden, Netherlands and the U.S have likewise shown a similar pattern.
The apparent decline in the incidence of Alzheimer's disease may have something to do with better cardiovascular health, said U.S. study researcher Claudia Satizabal, from the Boston University School of Medicine. For their study, Satizabal and colleagues observed that people's average blood pressure and cholesterol levels have improved while the incidence of heart disease, stroke and smoking has declined.
Dean Hartley, from the nonprofit Alzheimer's Association, said that Satizabal's explanation is plausible as studies have found an association between better cardiovascular health and reduced risks for Alzheimer's disease. This possibly happens because having a healthy heart and blood vessels allows oxygen and energy to be delivered more efficiently to the brain cells.
A study conducted by Miia Kivipelto, from the Karolinska Institute in Sweden, and colleagues involved 1,260 volunteers in Finland. It showed hints on how to reduce risks for Alzheimer's, a condition that commonly affects older adults.
For the study, the researchers divided the participants into two groups. One group was given standard care while the other group adopted lifestyle changes. After two years, those in the group that exercised and had healthier diets, managed their heart-health risk factors and were doing brain training outperformed those in the control group in memory and cognitive tests.
"We were surprised that were able to see a clear difference already after two years," Kivipelto said. "We thought that two years may not be enough, but the multidomain approach seems to be an effective way of doing something to protect memory."
Ronald Petersen, from the Mayo Clinic in Rochester, Minn., also provided tips on how to reduce risks of developing Alzheimer's disease in the future.
"By our watching our own vascular risk factors, our blood sugar, our blood pressure, our weight, and engaging in active activities and engaging in cognitive activities that actually stimulate our mind, we might be able to actually reduce the risk of us developing Alzheimer's Disease in the future," Petersen said.