Should You Find Out if You’re at Risk of Alzheimer’s?

With a genetics test, some people are learning they have a higher risk of Alzheimer’s. Can you do anything to prevent the disease? Yes you can, however the first step is to determine your risk. Once you know or have greater insight to your own person risk, practitioners can guide you to determine your most important preventative plan of action to minimise the development of the disease.

Everyone has two copies of the apolipoprotein E, or APOE, gene—one inherited from each parent. There are three variants of the gene. The e4 variant is associated with a heightened Alzheimer’s risk.

About 20% of the population has one or two copies of the e4 variant, said Rudy Tanzi, professor of neurology at Massachusetts General Hospital and Harvard Medical School and co-director of the McCance Center for Brain Health. One copy increases your risk of developing Alzheimer’s disease three- to four-fold, according to studies. About 2% of the world’s population has two copies of the e4 variant, which can increase the risk by as much as 14-fold, Dr. Tanzi said.

There is no advice derived from randomized- controlled trials—the gold standard in medicine —on preventing Alzheimer’s disease. But most doctors agree that regular exercise, adequate sleep and a heart-healthy diet can lower the risk. “The Healing Self,” which Dr. Tanzi wrote with Deepak Chopra, advocates for protecting the brain by focusing on sleep, exercising, learning things, controlling stress and hypertension, as well as maintaining social interaction and a healthy diet.

The APOE gene teaches the body how to produce apolipoprotein E, which carries fats, such as cholesterol, from cell to cell. Most people have the APOE3 variant, which conveys no extra risk for Alzheimer’s—or protection against the disease, Dr. Tanzi said. A small percentage of the population has one copy of the e2 variant of the gene, which can protect against Alzheimer’s disease. The impact of the e4 gene varies greatly by individual.