Alzheimer's is a complex disease that progresses over many years, like diabetes, heart disease, and other chronic conditions. A number of factors may increase or decrease a person's chances of developing the disease. These risk factors include age, genetics, environment and lifestyle.
We can’t control some risk factors for Alzheimer's disease such as age and genetic profile. But scientists are studying a number of other factors that could make a difference. Research suggests that certain lifestyle factors, such as a nutritious diet, exercise, social engagement, and mentally stimulating pursuits, might help to reduce the risk of cognitive decline and Alzheimer's disease.
Scientists are investigating associations between cognitive decline and heart disease, high blood pressure, diabetes, and obesity. Understanding these relationships and testing them in clinical trials will help us understand whether reducing risk factors for these diseases may help with Alzheimer's as well.
Research shows that Alzheimer’s disease causes changes in the brain years and even decades before the first symptoms appear, so even people who seem free of the disease today may be at risk. Scientists are developing sophisticated tests to help identify who is most likely to develop symptoms of Alzheimer’s. Ultimately, they hope to prevent or delay dementia in these high-risk individuals.
Age is the best known risk factor for Alzheimer’s disease. The risk of developing the disease doubles every 5 years after age 65. Alzheimer’s becomes increasingly common as people reach their 80s, 90s, and beyond. These facts are significant because the number of older adults is growing. The U.S. Census Bureau estimates that Americans 65 and older will grow from 13 percent of the population today to nearly 20 percent in 2030. The group with the highest risk of Alzheimer’s—those older than 85—is the fastest growing age group.
The more researchers learn about Alzheimer’s disease, the more they realize that genes play an important role in its development. Scientists have found genetic links to both early-onset and late-onset Alzheimer’s disease.
Early-onset Alzheimer’s is rare, accounting for only about 5 percent of people with the disease. Its symptoms usually appear when people are in their 30s, 40s, and 50s. Most cases of early-onset Alzheimer’s are familial, caused by mutations (permanent changes) in one of three known genes inherited from a parent.
Late-onset Alzheimer’s disease, the most common type, typically becomes evident after age 60. The causes of late-onset Alzheimer’s are not yet completely understood, but researchers have identified several risk-factor genes. One of those genes, called apolipoprotein E (APOE), has three forms, or alleles (ε2, ε3, and ε4).
One form, APOE ε4, increases a person’s risk of getting the disease. It is present in about 25 to 30 percent of the population. However, carrying APOE ε4 does not necessarily mean that a person will develop Alzheimer’s, and people without APOE ε4 can develop the disease.
Scientists have identified a number of other genes that may increase a person’s risk for late-onset Alzheimer’s. More studies are needed to assess the role these genes may play and to search for additional risk-factor genes. Knowing about these genes can help researchers more effectively test possible treatments and prevention strategies in people who are at risk of developing Alzheimer’s—ideally, before symptoms appear.
Genetic testing cannot predict who will or will not develop late-onset Alzheimer’s. Currently, it is used only in research settings and for people with a family history of early-onset Alzheimer’s disease. This type of testing is not recommended for people at risk of late-onset Alzheimer’s. It is not conclusive, and its primary value at this point remains in research settings.
Elder Options of Texas
All Rights Reserved
DISCLAIMER: Links to other websites or references to products, services or publications do not imply the endorsement or approval of such websites, products, services or publications by Elder Options of Texas. The determination of the need for senior care services and the choice of a facility is an extremely important decision. Please make your own independent investigation.