Early-Onset Alzheimer’s: The Earliest Signs of the Disease Found in Young Adults

a person seated on curved staircase, representing early-onset Alzheimer’s
The impact of early-onset Alzheimer’s can be personally and financially daunting.Getty Images

Alzheimer’s disease develops when neurons (nerve cells) in the brain stop functioning, lose connections with other neurons, and eventually die.

Although Alzheimer’s dementia typically affects people who are 65 and older, it can also appear in people who are much younger.

Of the estimated 5.8 million Americans living with Alzheimer’s dementia, around 200,000 develop it before age 65. They may be in their fifties, forties, or even their thirties. (1)

Early-onset (also called younger-onset) Alzheimer’s and late-onset Alzheimer’s disease usually affect the brain in similar ways, but the issues each raises for the person who has it — involving everything from getting an accurate diagnosis to coping with the financial repercussions — can be very different.

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Genetic Risk Factors to Consider

For most people with early-onset and late-onset Alzheimer’s, the disease appears to be caused by a combination of genetics, lifestyle, and environmental influences interacting in ways that are still not clearly understood.

Researchers have made progress in identifying genes that raise the risk of both early-onset and late-onset Alzheimer’s.

Having a variant of the apolipoprotein E (APOE) gene increases the odds of developing Alzheimer’s in people of all ages, though it does not mean someone will definitely get the disease. People with this variant, APOE e4, are not only more vulnerable to Alzheimer’s, but symptoms tend to appear at a younger age. (2)

A subset of cases of Alzheimer’s in young adults — between 7 and 12 percent — have a rare form that is directly caused by mutations (defects) in three specific genes.

Anyone who inherits one of these mutations has a very strong probability of developing Alzheimer’s at a young age.

Called familial Alzheimer’s disease, this kind of Alzheimer’s disease affects only about 500 known families around the world. Researchers estimate that it accounts for much less than 1 percent of all cases of Alzheimer’s disease. (3)

The three mutations linked to this form of early-onset Alzheimer’s — amyloid precursor protein (APP), presenilin 1(PSEN1), and presenilin 2 (PSEN2) — result in the production of abnormal proteins associated with Alzheimer’s disease. (2)

Beta-Amyloid Plaques in Young Adult Brains

Studies show that the brains of people with Alzheimer’s dementia — including Alzheimer’s in young adults — contain a large amount of amyloid plaques (abnormal protein deposits) as well as neurofibrillary tangles (twisted strands of a protein called tau).

Plaques form when pieces of a protein called beta-amyloid clump together. Researchers are beginning to think that groups of a few pieces of beta-amyloid, rather than plaques, may cause the worst damage by blocking the chemical signals that neurons use to communicate. (4)

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Early-Onset Alzheimer’s Symptoms

For most people, the symptoms of early-onset Alzheimer’s mirror those of the late-onset kind, with memory loss usually the first sign of a problem.

But when younger people develop Alzheimer’s dementia, they are more likely than older people to develop what’s called an atypical version.

These rarer forms make up 30 percent of all cases of early-onset Alzheimer’s but only 5 percent of late-onset cases. (3)

Rather than memory loss, initial symptoms of atypical Alzheimer’s dementia may include:

  • Vision problems, even when the eyes are healthy, such as difficulty identifying objects or reading, struggling to judge distances, problems coordinating movement (such as when getting dressed)
  • Problems with language, such as trouble using the correct words; the person may take long pauses while speaking
  • Difficulty with planning and decision-making
  • Changes in mood and personality; the person may behave in socially inappropriate ways or seem not to care how others feel (5)

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Getting the Right Diagnosis

Getting an early-onset Alzheimer’s diagnosis can be difficult because doctors don’t typically look for the disease in younger people.

Instead, healthcare professionals may blame symptoms on stress, menopause, depression, or other conditions. (6)

As a result, patients grappling with confusing symptoms may not get the treatment they need.

Younger people with atypical Alzheimer’s face an even bigger challenge in getting an accurate diagnosis.

To understand what’s causing symptoms, a doctor should conduct a thorough investigation that includes a detailed family history, physical and neurological tests, a cognitive assessment, and possibly a brain-imaging scan to rule out conditions like a stroke or brain tumor.

Physicians may also use genetic testing to help diagnose early-onset Alzheimer’s disease. (2)

Treating Early-Onset Alzheimer’s Disease

There are a few drugs that may help anyone with Alzheimer’s disease maintain cognitive function for a limited period of time. These include:

Other therapies, including other medication, may also help treat common behavioral and psychiatric problems associated with Alzheimer’s dementia.

These include depression, anxiety, sleeplessness, wandering, or agitation. (7)

The Impact of Early-Onset Alzheimer’s Disease on Your Family

People who develop Alzheimer’s dementia in their thirties, forties, or fifties face unique social, emotional, and financial challenges.

Many people with this diagnosis may still be raising children. Contemplating the impact of the disease on family life can cause grief and anxiety, but it’s important that kids understand what’s happening.

A few pieces of advice from the Alzheimer’s Association:

  • Be open about the changes in your health and life.
  • Take steps to address the child’s emotional needs, such as meeting with a counselor who focuses on helping families cope with chronic illness.
  • Make sure the child’s teachers and school social workers are aware of what’s happening.
  • Stay involved in the child’s life and plan activities you can still do together. If driving is no longer possible for you, plan a hike or bike ride.
  • Humor helps. Find things you can laugh about together.
  • Record your thoughts and feelings in a journal or on video or audio for your child to have later in life. (8)

The Financial Implications of Early-Onset Alzheimer’s

People with early-onset Alzheimer’s disease may be facing a daunting financial future, particularly if their job is their main source of income.

Those who are still working may be eligible for disability benefits or may be able to use benefits offered under the federal Family and Medical Leave Act, which allows up to 12 weeks of unpaid, job-protected leave each year for family and medical reasons with continuation of group health insurance coverage.

People who need to leave their jobs may be able to retain employer-sponsored healthcare coverage for as long as 36 months (depending on the circumstances) under the federal law COBRA.

The Health Insurance Marketplace in each state, created by the Affordable Care Act (ACA), is another option for healthcare coverage. ACA health plans cannot refuse coverage to people with preexisting conditions, meaning no one can be denied insurance because of an Alzheimer’s diagnosis.

The Social Security Administration has added early-onset Alzheimer’s disease to its list of conditions under the Compassionate Allowances initiative.

This means people younger than 65 who qualify have expedited access to Social Security Disability Insurance and Supplemental Security Income.

Talking with a financial planner who is familiar with elder care or long-term-care planning may be helpful in understanding the choices and taking a proactive approach. (6)

Editorial Sources and Fact-Checking

Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.

Resources

  1. 2019 Alzheimer’s Disease Facts and Figures. Alzheimer’s Association.
  2. Alzheimer’s Disease Genetics Fact Sheet. National Institute on Aging. December 24, 2019.
  3. Young-Onset Dementia. Alzheimer’s Society.
  4. Inside the Brain: A Tour of How the Brain Works, Part 2: Alzheimer’s Effect. Alzheimer’s Association.
  5. Symptoms of Alzheimer’s Disease. Alzheimer’s Society.
  6. If You Have Younger-Onset Alzheimer’s Disease. Alzheimer’s Association.
  7. How Is Alzheimer’s Disease Treated? National Institute on Aging. July 8, 2021.
  8. Helping Friends and Family. Alzheimer’s Association.
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