Is Alzheimer's Disease Genetic?

Older BIPOC woman with her doctor

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Alzheimer's disease is a neurological condition that causes cognitive decline. It causes memory loss and difficulties with thinking processes.

It can also severely disrupt your ability to function daily. While researchers don't fully understand what causes Alzheimer's, some research suggests that genetic mutations could be responsible.

The link between Alzheimer's disease and genetics means that the disorder can be inherited from a close relative.

This article looks into the signs and symptoms of the condition and how the disease can be inherited. 

What Is Alzheimer's Disease?

Alzheimer's disease is a brain disorder that causes severe cognitive decline in older people. It's one of the leading causes of dementia. Dementia is a condition that affects how a person thinks, functions, and behaves. It also mainly affects a person's memory and how new memories are formed. 

There are two forms of the condition. Early-onset Alzheimer's occurs in people between the ages of 30 and 60. It is also very rare. Late-onset Alzheimer's is the more common form of the condition.

The condition is named after Dr. Alois Alzheimer, who observed abnormalities in the brain of a woman who had died due to a suspected mental illness. He noticed unusual clumps called amyloid plaques on her brain. This build-up can be observed in the brains of people who have the condition today. 

Signs & Symptoms of Alzheimer's Disease 

Signs of Alzheimer's disease vary from person to person, especially in the early stages. In the early stage of Alzheimer's, people with the condition are likely to exhibit the following signs: 

  • Difficulty completing everyday tasks 
  • Getting lost frequently
  • Behavioral changes 
  • Personality changes 

As the disease progresses, symptoms of the condition worsen and affect a person's ability to function effectively. Signs of the moderate and later stages of Alzheimer's disease include: 

Alzheimer's Disease Diagnosis 

An accurate diagnosis of Alzheimer's needs to be made by a specialist. This person might be a neurologist or a geriatric psychiatrist. It's likely that they will request brain imaging tests like MRIs or a CT scan to confirm an Alzheimer's diagnosis.

Is Alzheimer's Disease Genetic? 

Researchers have observed that a genetic mutation is responsible for many cases of Alzheimer's disease. However, they've been unable to identify which specific gene is responsible for the condition.

Alzheimer's disease can be classified into early-onset Alzheimer's and late-onset Alzheimer's. Less than 10% of people with Alzheimer's have early-onset Alzheimer's. A percentage of this number is thought to be caused by inherited genes. This means a close relative passed down a mutated gene that led to the development of the condition.

"Alzheimer's disease typically starts in older people aged 60 and above. It is associated with a gene called Apolipoprotein E4 (APOE4). Possessing APOE4 can increase the risk of developing Alzheimer's. Studies have found having two copies of APOE4 can increase risk by ten-fold, says Nikhil Palekar, MD, Medical Director of the Stony Brook Center of Excellence for Alzheimer's Disease.

Dr. Palekar also notes that a person's risk of being diagnosed with Alzheimer's disease increases three-fold if they have one copy of APOE4. "This is a similar risk if you have a first-degree relative with Alzheimer's disease," says Dr. Palekar.

Is There a Way to Know If I Will Develop Alzheimer's Disease? 

Several early signs of Alzheimer's disease include poor judgment, difficulty understanding tasks, and minor memory lapses. Knowing these early signs and getting an accurate early diagnosis can help with the effective management of the condition. However, there's no way to know if you'll develop the disease before these signs begin to show.

Certain factors put you at a higher risk of developing the condition, and learning them could help you understand your chances of getting the disease. They include: 

  • Age: Alzheimer's most commonly develops in people who are 65 years old or older. In cases of early-onset Alzheimer's, you may be diagnosed at an earlier age.
  • Gender: Alzheimer's is twice as likely to develop in women than in men. Although some research has linked Alzheimer's to menopause, childbirth, and the likelihood of women living longer than men, researchers are unsure why this occurs.
  • Genetics: If you have a family history of this condition, you are more likely to develop it. This risk heightens when you have multiple family members diagnosed with the disease.

"Getting tested for the APOE4 gene can provide information if you are at risk of potentially developing Alzheimer's disease. However, it cannot provide a definite answer if you will go on to develop Alzheimer's disease. Currently, there is no definitive way to know if one will develop Alzheimer's disease in people 60 plus," says Dr. Palekar.

Can Alzheimer's Disease Be Prevented? 

Unfortunately, there isn't much to be done to avoid certain risk factors such as gender and age that increase the risk of developing Alzheimer's disease.

Research does show that specific lifestyle changes could help. Maintaining a healthy diet, exercising regularly, and cutting down on smoking and drinking alcohol could reduce your risk of developing the disease.

In cases where the disease has already developed, these lifestyle changes could also potentially help slow the disease's progression.

How Is Alzheimer's Disease Treated?

There is currently no cure for Alzheimer's disease. However, scientists have developed treatments that can reduce the severity of some of the condition's debilitating symptoms.

Treating Alzheimer's disease effectively typically involves a combination of medication and therapy. Specific lifestyle changes are also recommended to help a person with the condition live a more fully functioning life.

Medication 

The FDA has approved many medications to help reduce the severity of the more debilitating symptoms of Alzheimer's disease. Some of the most commonly prescribed include Aricept (donepezil), Razadyne (galantamine), and Exelon (rivastigmine). These drugs are formulated to treat varying stages of dementia caused by Alzheimer's disease. 

Aduhelm Is the Only FDA-Approved Drug That Treats Alzheimer's Specifically

So far, Aduhelm (aducanumab) is the only drug that the FDA has approved for the treatment of Alzheimer's disease itself. The drug is formulated to help shrink the build-up of amyloid deposits in the brain.

Amyloids are abnormal proteins that have been observed to build up in the brains of people with Alzheimer's disease and are linked to the development of the condition. Aduhelm is also thought to be able to slow down the progression of Alzheimer's disease. However, Aduhelm hasn't quite proven to be effective in this regard and is currently approved under the accelerated approval program of the FDA.

What this means is that Aduhelm's approval is conditional. While the drug is expected to be able to reduce the build-up of amyloid plaques, this has to be verified in trials before the drug can be given full approval.

While Aduhelm has been shown to shrink amyloid proteins in the brain, researchers are unsure if the drug can effectively slow down the progression of Alzheimer's disease. More trials are needed to see if this drug can slow the disease's progression.

Frequently Asked Questions 

Frequently Asked Questions

  • How many people have been diagnosed with Alzheimer's disease?

    More than 6 million Americans who are 65 years old or older have been diagnosed with Alzheimer's disease.

  • Is Alzheimer's disease fatal?

    Alzheimer's is a progressive disease, which means it worsens over time. Some research suggests that a person with Alzheimer's has an average of four to eight years to live after a diagnosis has been made.However, if an early diagnosis is made and proper care and treatment are provided, a person with Alzheimer's disease could live for up to 20 years after diagnosis.

9 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute on Aging. What is Alzheimer's disease?.

  2. National Institute on Aging. Alzheimer’s disease fact sheet. July 8, 2021

  3. National Institute on Aging. Early-onset Alzheimer's disease: a resource list. January 30, 2020

  4. AARP. Women are more likely than men to develop Alzheimer's.

  5. National Institutes of Health (NIH). Combination of healthy lifestyle traits may substantially reduce Alzheimer’s.

  6. National Institute on Aging. Cognitive health and older adults.

  7. Research C for DE and. Aducanumab (Marketed as aduhelm) information. FDA. Published online August 7, 2021.

  8. Alzheimer’s Association Report. 2020 Alzheimer’s disease facts and figures.

  9. Alzheimer's Association. Stages of Alzheimer's.

By Toketemu Ohwovoriole
Toketemu has been multimedia storyteller for the last four years. Her expertise focuses primarily on mental wellness and women’s health topics.