Dementia is an umbrella term for a range of conditions that affect the brain. Symptoms often include difficulties with memory, problem-solving, language, and judgment.

While dementia mainly affects older adults, it is not a regular, expected part of aging. The World Health Organization (WHO) report that 5–8% of people aged 60 or older have dementia.

While there is no guaranteed way to prevent it, some strategies may help, and early detection and treatment may slow its progression.

In this article, we look at what dementia is, its symptoms, when to see a doctor, and more.

In image of an older person who may have symptoms of dementia.Share on Pinterest
Getty Images

“Dementia” refers to a group of neurodegenerative diseases characterized by severe cognitive decline.

This decline involves difficulty with memory, concentration, communication, and making decisions. A person may also experience changes in their mood and behavior.

Dementia is often progressive — symptoms are usually mild to begin with and become more severe over time.

During the early stages of dementia, the symptoms may be mild and easy to overlook.

Broadly, some symptoms that can occur early on include:

  • Memory difficulties: A person may have trouble with short-term memory and struggle to remember what they ate for breakfast, for example.
  • Difficulty concentrating: This may involve, for instance, being unable to follow a conversation.
  • Disorientation: This might involve confusion about times and locations. For example, a person may forget where they are going and struggle to get back home.
  • Communication problems: A person may forget common words or substitute words that do not fit the context. This can cause their speech and writing to be difficult to understand.
  • Trouble with spatial awareness: A person may have difficulty judging distances and spaces, causing them to bump into things.
  • Difficulty performing routine tasks: For example, a person may have trouble remembering which clothes to put on first or the steps involved in cooking a familiar meal.

As dementia progresses, the symptoms become more noticeable. A person may:

  • become more forgetful
  • become lost in their home
  • have increasing difficulty with communication
  • need more help with caring for themselves
  • demonstrate changes in behavior, such as repeatedly asking the same questions

By this stage, the symptoms have become more severe:

  • Memory problems: A person may not recognize their home or close family members.
  • Communication problems: A person may lose the ability to speak. It can help to communicate with them using facial expressions, gestures, and touch.
  • Behavioral and psychological changes: People may become agitated, depressed, or anxious, and they may hallucinate or walk around with no apparent aim.
  • Bladder incontinence: This can occur during the later stages of dementia.
  • Appetite and weight loss: People may have difficulty eating and swallowing. They may also lose their appetite, resulting in weight loss.

Learn how dementia progresses here.

There are different types of dementia, and each has characteristic symptoms.

Learn more about the types of dementia here.

Alzheimer’s disease

Symptoms include:

  • having memory problems
  • being confused in unfamiliar environments
  • repeating questions
  • having trouble finding the right words
  • becoming anxious and withdrawn
  • having trouble with numbers and money
  • having difficulty with everyday tasks

Learn more about Alzheimer’s disease here.

Vascular dementia

Symptoms include:

  • mood changes
  • trouble with thinking, such a difficulty paying attention
  • movement challenges, such as finding it difficult to walk
  • symptoms similar to those of a stroke, such as muscle weakness and temporary paralysis

Learn more about vascular dementia here.

Lewy bodies dementia

Symptoms include:

  • disturbed sleep
  • repeated fainting and falls
  • slowed physical movements
  • visual hallucinations
  • fluctuating levels of confusion
  • periods of being noticeably drowsy or alert

Frontotemporal dementia

Symptoms include:

  • personality changes, such as becoming less sensitive to others’ feelings
  • a lack of social awareness or tact, such as by making inappropriate jokes
  • difficulty with language, such as being unable to find the right words
  • obsessive behaviors

Learn more about frontotemporal dementia here.

Dementia can result from various brain injuries and diseases.

Alzheimer’s disease is the most common cause of dementia and accounts for roughly 70% of cases.

Each type has slightly different effects on the brain. For example:

  • Alzheimer’s disease: In a person with Alzheimer’s, nerve tissue in the brain contains tiny protein deposits called plaques and tangles. These surround the cells and damage their internal structures, resulting in cell death.
  • Vascular dementia: In a person with vascular dementia, a lack of blood flow in the brain reduces the supply of oxygen, causing brain cell damage or death. A stroke or damaged blood vessels can be the underlying cause.
  • Lewy bodies dementia: In someone with this type of dementia, deposits of tiny structures called Lewy bodies form inside brain cells. These proteins interfere with the brain’s functioning and lead to the death of brain cells.
  • Frontotemporal dementia: This refers to damage to front and side areas of the brain. In a person with frontotemporal dementia, aggregations of proteins inside brain cells cause the cells to die.

Less often, the following can cause dementia:

To treat dementia, a doctor may prescribe one of the following medications:

  • donepezil (Aricept)
  • galantamine (Razadyne)
  • rivastigmine (Exelon)

These drugs are cholinesterase inhibitors. They help by increasing levels of the neurotransmitter acetylcholine, which plays a role in memory and judgment.

For some people, doctors also prescribe memantine (Namenda), which is an N-methyl-D-aspartate, or NMDA, receptor antagonist. It blocks chemicals that may damage brain cells.

These four drugs are currently the only effective licensed treatments for dementia.

For a person with vascular dementia, a doctor will likely also prescribe drugs to treat the underlying issue, which may be a stroke or blood vessel damage.

Also, a person with dementia may benefit from nondrug treatments, such as:

  • activities that promote mental and social stimulation
  • memory training
  • physical exercise

There is no single test for dementia. A doctor may diagnose it after performing:

  • A physical examination and blood tests: These can rule out other possible causes of symptoms.
  • Cognitive assessments: These are tests that help check a person’s memory and thinking.
  • Brain scans: This might involve a CT scan or an MRI.

Learn more about the diagnostic options for dementia here.

Anyone who has concerns about their memory should contact a doctor.

If a person notices dementia-like symptoms in someone else, they should encourage them to see a doctor. It may help to accompany the person to the appointment and provide emotional support.

Caring for someone with dementia can be challenging, and at times it can feel overwhelming.

The following nonprofit organizations provide information and support:

There is no guaranteed way to prevent dementia.

A 2017 review of preventive measures concludes that the following may have some benefit:

  • getting regular exercise
  • having a healthful diet
  • limiting psychosocial stress
  • limiting any major depressive episodes

People with dementia go through the stages at different speeds and experience different symptoms. However, the symptoms usually worsen with time.

There is no cure for many of the common types of dementia. Receiving the diagnosis early on can help a person and their loved ones plan for the future.

Researchers continue to work hard to find new treatments and possible cures.

Dementia refers to a range of conditions that affect memory, problem-solving, language, and judgment. Usually, the symptoms are mild and gradually worsen over time.

There is no cure for the more common types of dementia. However, a combination of medication and stimulating activities may help slow the progression of the illness.