About Dementia

What to know

  • Dementia is a condition that makes someone unable to remember, think clearly, or make decisions while doing everyday activities.
  • Alzheimer’s disease is the most common type of dementia.
  • Learn about the different types of dementia.
Older man looks out of a window

Overview

Dementia

Dementia is not a specific disease. It is an overall term that describes a decline in mental ability that interferes with daily life. It affects memory, thinking, and behavior.

People with dementia often have symptoms like trouble remembering, thinking, or making everyday decisions. These symptoms tend to get worse over time.

There are many types of dementia.

  • Alzheimer’s disease is the most common type of dementia.
  • Each form of dementia has a different cause.

Though dementia mostly affects older adults, it is not a part of normal aging.

A growing problem

An estimated 6.7 million older adults have Alzheimer's disease in the United States. That number is expected to double by 2060.[1]

Projected number of adults with Alzheimer's disease by 2060‎

By 2060, nearly 14 million adults are projected to have Alzheimer's disease in the United States.

Most common types

Alzheimer's disease

Alzheimer's is the most common type of dementia. It accounts for 60% to 80% of cases1.

Cause: Many factors play a role in causing Alzheimer's, including genetics, behaviors, and habits.2

Symptoms: Symptoms include problems with short-term memory, paying bills, preparing meals, remembering appointments, or getting lost in familiar areas.

Risks: Having a close relative (like a parent or sibling) with Alzheimer's disease increases a person's chance of developing it. However, there are many things you can do to reduce your risk, such as being physically active, and controlling your blood pressure.3

Vascular dementia

Vascular dementia is the second most common type of dementia. It accounts for about 5%−10% of cases.

Cause: Vascular dementia results from strokes or other problems with blood flow to the brain. Symptoms gradually become worse as blood vessels get damaged.

Symptoms: Symptoms vary depending on the area of the brain that is affected.

Risks: Other conditions that damage blood vessels can also increase a person's risk of developing vascular dementia. These include diabetes, high blood pressure, and high cholesterol.

Lewy body dementia

Lewy body dementia can cause problems with thinking, movement, behavior, and mood.

Cause: This type of dementia is caused by abnormal deposits of a protein in the brain, called "Lewy bodies." These deposits affect chemicals in the brain.

Symptoms: This type of dementia may cause memory loss, as well as movement or balance issues like stiffness or trembling. Many people with this type of dementia also experience daytime sleepiness, confusion, staring spells, sleep disturbances, or visual hallucinations.

Risks: Researchers have not yet identified specific genes or risk factors linked to Lewy body dementia. Most people diagnosed have no family history of the disorder.

Fronto-temporal dementia

Frontotemporal dementia (FTD) affects the frontal (front) and temporal (side) lobes in the front of the brain. It often leads to changes in personality and behavior. FTD is a common cause of dementia that affects younger people.

Cause: FTD is the result of damage to nerve cells in the frontal and temporal lobes of the brain.

Symptoms: A person with FTD may experience increasing difficulty planning or organizing activities. They may act inappropriately in social or work settings and have trouble communicating with others.

Risks: About one-third of all FTD cases are inherited through genes. Having a family history of FTD or a similar disorder are the only known risk factors.

Mixed dementia

More than one type of dementia can affect the brain at the same time. For example, a person may have Alzheimer's disease and vascular dementia. It is not always obvious that a person has mixed dementia.

Lower Your Risk‎

Nearly 40% of all dementia cases may be prevented or delayed by making healthy lifestyle changes.4

These changes can also help lower your risk of other chronic diseases.

Take charge of your brain health and reduce your risk.


Testing and diagnosis

Importance of testing

If you think you or a loved one may have dementia, talk to a health care provider. The provider can work with you to figure out the problem and what might be causing it.

  • Some memory problems may be caused by treatable conditions. These problems can be reversed when the underlying condition is treated. Examples include:
    • Side effects of medication.
    • Increased brain pressure.
    • Vitamin deficiency.
    • Thyroid hormone imbalance.
  • Some memory problems may be due to dementia. The sooner you can diagnose dementia, the sooner you can begin to treat it to slow its progression.

Types of testing

Health care providers will:

  • Look for problems with attention, memory, problem solving, and other brain functions to understand the problem.
  • Assess your brain to figure out the underlying cause.

Assessment may include taking a medical history and tests such as:

  • A physical exam and diagnostic tests.
  • Neurological exam.
  • Depression screening.
  • Blood tests.
  • Brain scans, like computed tomography (CT) or magnetic resonance imaging (MRI).

Treatment for dementia

The type of treatment used for dementia depends on the underlying cause.

  • Symptom relief: There are prescription drugs that temporarily ease some symptoms. Most of these drugs work best for people in the early or middle stages of dementia.
  • Delay disease: There are other prescription drugs that can slow the progression of dementia.

Resources

  1. Alzheimer’s Association. 2024 Alzheimer’s disease facts and figures. Alzheimers Dement. 2024;20(5):3708-3821. doi:10.1002/alz.13809
  2. Omura JD, McGuire LC, Patel R, et al. Modifiable Risk Factors for Alzheimer Disease and Related Dementias Among Adults Aged ≥45 Years — United States, 2019. MMWR Morb Mortal Wkly Rep 2022;71:680–685. DOI: http://dx.doi.org/10.15585/mmwr.mm7120a2.
  3. The Alzheimer's Association. Risk Reduction. Accessed August 26, 2024. https://www.alz.org/professionals/public-health/public-health-topics/risk-reduction
  4. Livingston G, Huntley J, Sommerlad A, et al. Dementia Prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet.2020;396(10248):413-446 https://doi.org/10.1016/S0140-6736(20)30367-6