What Is Early-Onset Alzheimer’s Disease?

Alzheimer’s disease, which is named for the German physician who first identified it in 1906, is the most common form of dementia, accounting for 60 to 80 percent of cases. It is a progressive disorder of the brain and is characterized by a gradual deterioration of mental faculties caused by a loss of nerve cells and the connections between them.

The disease is often accompanied by changes in behavior and personality. Its course is relentless and relatively predictable, but the rate of mental decline varies from person to person. People who are age 65 and older survive an average of four to eight years after the initial Alzheimer’s diagnosis, but some people can live for 20 years or more after diagnosis.

Although Alzheimer’s disease most commonly affects older adults, it can also affect people in their 30s or 40s. When Alzheimer’s disease occurs in someone under the age of 65, it is known as early-onset (or younger-onset) Alzheimer’s disease. About 5 percent of people with Alzheimer’s disease have the early-onset form. Many of them are in their 40s and 50s when Alzheimer’s disease first manifests itself—when they have careers and families, or are taking care of someone with Alzheimer’s when they get their own diagnosis.

Types of early-onset Alzheimer’s

Most types of early-onset Alzheimer’s disease are the same, but there are a few small distinctions:

• Common Alzheimer’s disease. The majority of people with early-onset Alzheimer’s have the common form of the disease. It will progress in roughly the same way as it does in older people with Alzheimer’s disease.

• Genetic Alzheimer’s disease. This form is rare. Estimates of the percentage of all cases with abnormal genes as the cause vary from 1 to 5 percent. These people usually begin showing symptoms of the disease in their 30s, 40s, or 50s.

Why early-onset Alzheimer’s is often misdiagnosed

Early-onset Alzheimer’s is often mistaken for difficulty adjusting to changing life circumstances, such as children leaving home, loss of a job, or a midlife crisis. Recent research published in the journal Neurology suggests that many early-onset patients don’t necessarily have memory loss and may be incorrectly diagnosed because they have atypical symptoms.

Researchers assessed symptoms among 40 early-onset Alzheimer’s patients and the presence of the apolipoprotein E (APOE) genotype. They found non-memory symptoms in 38 percent of patients; most exhibited issues such as the inability to plan, organize, initiate, inhibit, and shift behaviors, as well as prioritize, control, or complete tasks.

They also found that 53 percent had incorrect initial diagnoses, compared with 4 percent misdiagnosis when memory loss was present. There was no difference in APOE frequency between patients with typical Alzheimer’s memory loss and those with atypical symptoms. However, patients with an Alzheimer’s family history were more than three times more likely to have the APOE genotype.

People concerned with their cognitive function, whether it is memory loss or changes in behavior or function, may want to be evaluated by a dementia specialist but should also have a caregiver or loved one monitor their condition.

Symptoms to watch for

For most people with early-onset Alzheimer’s disease, the symptoms will closely mirror those of other forms of Alzheimer’s disease.

Early symptoms:

Forgetting important things, particularly newly learned information or important dates

Asking for the same information again and again

Difficulty solving basic problems, such as keeping track of bills or following a favorite recipe

Losing track of the date or time of year

Losing track of where you are and how you got there

Difficulty with depth perception or other vision problems

Difficulty joining conversations or finding the right word for something

Misplacing things and not being able to retrace your steps to find it

Increasingly poor judgment

Withdrawal from work and social situations

Changes in mood and personality

Later symptoms:

Prominent mood swings and changes in behavior

Deepening confusion about time, place, and life events

Loss of job, volunteer positions, or an active social life

Suspicions about friends, family, or caregivers

Difficulty speaking, swallowing, or walking

Severe memory loss

How a diagnosis is made

The current diagnosis of early-onset Alzheimer’s disease relies on detecting the signs of mental decline. A doctor can then make a diagnosis of Alzheimer’s disease with a few tests.

First, the doctor will perform a medical history, and also conduct some cognitive tests of memory, problem-solving, and other mental skills. The doctor might also test the patient’s blood, urine, and spinal fluid. Finally, computed tomography (CT) and magnetic resonance imaging (MRI) scans of the brain can give the doctor a closer look at the brain tissue to reveal the extent of the damage.

Treatment for the disease

Like Alzheimer’s disease, early-onset Alzheimer’s disease currently has no cure. But doctors have had some success in helping people maintain mental function, control behavior, and slow the progression of the disease.

The drugs that are used to help people maintain mental function include donepezil (Aricept), rivastigmine (Exelon), galantamine (Razadyne) and memantine (Namenda). The results have been mixed, but these drugs seem to help people with their symptoms for anywhere from a few months to a few years.

Other therapies that may play a role in slowing the progress of early-onset Alzheimer’s disease include physical activity, cardiovascular and diabetes treatments, antioxidants, and cognitive training.

Genetic testing

The question of genetic testing when dementia begins before age 60 in a family member is best addressed individually for each person and each family. Consultation with a genetic counselor is a must if genetic testing is being considered.

Managing early-onset Alzheimer’s

Early-onset Alzheimer’s disease can be a difficult disease to cope with. If you have been diagnosed, the best thing you can do is have a positive outlook and stay as active and mentally engaged as possible.

It’s also important to realize that you are not alone. Rely on your friends and family as much as possible. And don’t be afraid to seek out a support group if you feel that it might be helpful.

When the disease is still in its early stages, it’s critical to think about the future. This can include: doing financial planning, working with employers on current and potential job responsibilities, clarifying health insurance coverage, and getting all your important documents in order should your health take a turn for the worse.

Meet Our Writer

HealthAfter50 was published by the University of California, Berkeley, School of Public Health, providing up-to-date, evidence-based research and expert advice on the prevention, diagnosis, and treatment of a wide range of health conditions affecting adults in middle age and beyond. It was previously part of Remedy Health Media's network of digital and print publications, which also include HealthCentral; HIV/AIDS resources The Body and The Body Pro; the UC Berkeley Wellness Letter; and the Berkeley Wellness website. All content from HA50 merged into Healthcentral.com in 2018.