A person showing another person with Alzheimer's Disease a photograph

Alzheimer’s Disease

Alzheimer's disease is a progressive neurological disease that ultimately results in the brain's inability to function correctly. 

Symptoms of Alzheimer's include problems with memory, communication, comprehension, and judgment. Changes in personality may also occur. As the disease progresses, the ability to function mentally, socially, and physically continues to decline.

Alzheimer's disease is the most common type of dementia and is typically seen in older adults. There is no cure, but symptoms can be managed through the use of behavioral strategies and medication.

Frequently Asked Questions

  • What causes Alzheimer's disease?

    The exact cause of Alzheimer's disease hasn't been identified. The current thinking is that it develops due to a combination of genetic, lifestyle, and environmental risk factors.1

    The brains of people with Alzheimer’s often show a build-up of proteins, known as plaques and tangles. Over time, these proteins can lead brain tissue to atrophy (shrink).

  • What is the difference between dementia and Alzheimer's?

    Dementia is a general term that covers many types of cognitive impairment. Alzheimer’s disease is the most common form of dementia; other types include vascular dementia and dementia with Lewy bodies. Symptoms vary among the types, but generally include memory loss, poor judgment, communication difficulties, and personality changes.

  • Is Alzheimer's genetic?

    Alzheimer’s disease is considered a complex “multifactorial” disorder, meaning it is caused by environmental circumstances combined with genetic factors. Recent research has identified several gene mutations that are linked with both late-onset and early-onset forms of the disease.

  • How is Alzheimer’s diagnosed?

    A definitive diagnosis of Alzheimer’s cannot be made until a brain autopsy after death. However, there are numerous tests that can be done at home or by a doctor that measure cognitive impairment and other factors that suggest Alzheimer’s, leading to a probable diagnosis.

  • Can you prevent Alzheimer's?

    There is no known way to prevent Alzheimer’s, since its causes are thought to be due to a variety of factors, including genetic and environmental factors. However, remaining intellectually and socially engaged throughout your life may contribute to brain health. Leading a healthy lifestyle by exercising and maintaining a healthy weight is good for overall health, including brain health.

  • Is there a cure for Alzheimer's disease?

    There is no cure yet for Alzheimer's disease, though there are strategies and medications that can keep symptoms under control. Meanwhile, research continues to reveal more about how Alzheimer's affects the brain, which may ultimately lead to the development of a cure.

  • Is Alzheimer's a disease?

    Alzheimer’s is a complex disease with many manifestations. Symptoms increase in severity as it progresses through three main stages—early-, mid-, and late-stage disease. The cause of death in someone with Alzheimer’s is often related to a physical complication, such as aspiration pneumonia due to a decline in the ability to swallow.

  • What are the early signs of Alzheimer’s?

    The ten most common signs of Alzheimer’s include: memory changes; withdrawal from usual activities; disorientation to time and place; visual-spatial difficulties; decrease in written or verbal communication ability; challenges in problem-solving and planning; personality and mood changes; misplacing items frequently; decline in judgment; and difficulty performing familiar tasks. These signs often become more severe as the disease progresses.

Key Terms

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