Your Guide to Understanding Dementia

Medically Reviewed By Nancy Hammond, M.D.

Dementia refers to a group of symptoms related to a progressive deterioration of brain function. Dementia typically involves memory loss and at least one other category of loss, such as language, visuospatial, or executive function. Also called major neurocognitive disorder, dementia can also affect thought processes, judgment, and behavior. It is not a typical part of aging, but instead goes beyond occasional forgetfulness and makes it difficult for a person to remember, learn, and communicate.

This article provides an overview of dementia, including its types, causes, symptoms, and treatments.


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“Dementia” is a general term that describes a decline in memory and other cognitive functions that interfere with daily activities. Most cases of dementia are progressive and irreversible. 

Progressive types of dementia include: 

  • Alzheimer’s disease: This is the most common type Trusted Source National Institute on Aging Governmental authority Go to source of dementia in older adults, characterized by changes in the brain that interfere with memory. Treatment may slow mental decline, but it is a progressive condition with no cure.
  • Frontotemporal dementia: Loss of nerve cells in the frontal and temporal lobes of the brain leads to this rare form of dementia. It can affect people younger than 65 Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source and often runs in families.
  • Lewy body dementia: Lewy bodies are abnormal accumulations of a protein in brain cells. Trembling, stiffness, and slow movements are characteristics of dementia with Lewy bodies (DLB) and Parkinson’s disease with dementia (PDD).
  • Vascular dementia: With this type of dementia, brain cells die because they do not get enough freshly oxygenated blood. Vascular dementia is often associated Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source with stroke.
  • Mixed dementia: This is a combination of more than one form of dementia.

Learn more about the types of dementia and the difference between Alzheimer’s disease and dementia.


The World Health Organization Trusted Source World Health Organization Highly respected international organization Go to source describes three general stages of dementia:

  • Early stage dementia: In this stage, people can generally still function independently. The symptoms may be subtle and can include disorientation in familiar places, forgetfulness, and reduced time management.
  • Middle stage dementia: People in this stage need more assistance with daily activities. The symptoms become more pronounced and may include forgetting events and personal history, confusing words, and wandering.
  • Late stage dementia: People in this stage require full-time care. They may no longer respond to their environment, be able to carry on conversations, or recognize loved ones.

Not everyone goes through the stages in the same way, and the stages can overlap.

Learn more about the stages of dementia.


Dementia symptoms may be subtle at first and then slowly become more noticeable — both by you and others around you. Common symptoms include:

  • changes in mood, personality, or behavior
  • changes in sleep patterns
  • confusion
  • difficulty performing complex tasks
  • impaired reasoning
  • impaired spatial ability and orientation
  • inability to manage finances, pay bills, or balance the checkbook
  • loss of judgment
  • social withdrawal
  • difficulty with:
    • memory
    • thinking
    • talking
    • comprehension
    • writing
    • reading

Causes and risk factors

Dementia is the result of damage to or loss of nerve cells in the brain. It can also occur when connections between nerve cells no longer function the way they should.

Many different conditions can cause dementia and dementia-like symptoms. Some conditions that cause dementia run in families while others have specific risk factors.

Many progressive diseases can cause dementia, including:

Other factors that may contribute to dementia include:

Risk factors for dementia

Many factors may increase the risk of developing dementia. Not all people with risk factors will get dementia.

Some risk factors can’t be modified, such as advancing age and a family history of dementia. However, research from 2020 Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source lays out potentially modifiable risk factors for dementia, including:

Learn more about reducing your risk of dementia.


To diagnose dementia, your doctor will evaluate your symptoms and medical history, perform a physical exam, and order testing.

During the physical exam, your doctor will evaluate your neurological health. This may involve checking your reflexes, balance, and movement. Your doctor will also want to rule out any conditions that are treatable. 

Tests your doctor may use to diagnose dementia include:

  • blood tests to check for signs of infection or inflammation and levels of hormones, vitamins, and blood chemicals
  • cognitive and neuropsychological tests, which include testing memory, attention, problem-solving, judgment, language, and math skills
  • genetic testing for certain causes of dementia
  • imaging exams of the brain to look for signs of tumors, stroke, or other brain problems
  • psychiatric evaluations to rule out mental health conditions, such as depression

An accurate diagnosis may be difficult, as the types of dementia can appear similar and it’s possible to have more than one type.


In general, treatment depends upon the cause of dementia. For reversible causes, this may involve changing medications, correcting imbalances or deficiencies, or treating medical conditions.

For progressive dementia, medical treatments may help manage the symptoms.

Medications to manage symptoms

Medications cannot slow the progression of dementia, but they may help Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source temporarily stabilize symptoms. These medications include:

  • Cholinesterase inhibitors: These increase the availability of a chemical that is required for nerve signaling in the brain. Examples include donepezil (Aricept), galantamine (Razadyne), and rivastigmine (Exelon).
  • NMDA receptor antagonists: These medications, including memantine (Namenda), decrease the overexcitement of certain receptors in the brain that may contribute to the degenerative process.

Medications to manage behavioral changes

Medications are also available to help address some of the behavioral changes that may occur with dementia, including:

  • antianxiety medications, such as buspirone (Buspar)
  • antidepressants to stabilize moods, such as citalopram (Celexa) and fluoxetine (Prozac)
  • antipsychotics, such as haloperidol (Haldol) and risperidone (Risperdal), for severe behavioral symptoms
  • stimulants, such as methylphenidate (Methylin, Ritalin), to improve sleep disorders and moods

Palliative and hospice care

In late stage dementia, caregivers and care teams may choose to focus treatment on comfort and quality of life. This may include offering sensory connections, such as Trusted Source National Institute on Aging Governmental authority Go to source through light massage or soothing music.

Healthcare professionals who specialize in palliative or hospice care can work with family members to provide the care a person with severe dementia needs while also offering support to loved ones. They can also offer emotional guidance through the grief process.

Potential complications

As dementia progresses, the symptoms become more severe and can place someone at greater risk of serious illness or injury. Complications of dementia may include Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source :

  • falls
  • incontinence
  • infections
  • reduced nutrition
  • swallowing difficulties
  • delusions or hallucinations

Life expectancy

Dementia is typically associated with reduced life expectancy.

A large 2020 study of people with dementia found that the average life expectancy from the time of diagnosis was 5.1 years Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source . However, dementia progression can vary greatly between people and types of dementia, so everyone’s experience will be different.

Learn more about dementia outlook and life expectancy.


Dementia is the name for a group of conditions that result from a decline in brain function. Though dementia is progressive, treatments can help manage the symptoms.

Talk with a doctor about ways to manage dementia.

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Medical Reviewer: Nancy Hammond, M.D.
Last Review Date: 2024 Jan 3
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