Dementia is a loss of thinking, remembering and reasoning skills. Dementia isn’t a single disease or condition. Instead, it’s an umbrella term used to describe memory loss and a decline in cognitive function.

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What are the symptoms of dementia?

Dementia symptoms involve two areas of change, cognitive and psychological. Common signs and symptoms include:

Cognitive changes

  • Confusion and disorientation.
  • Difficulty communicating or finding words.
  • Difficulty handling complex tasks.
  • Difficulty reasoning or problem-solving.
  • Difficulty with coordination and motor functions.
  • Difficulty with planning and organizing.
  • Difficulty with visual and spatial abilities, such as getting lost while driving.
  • Memory loss, often noticed by someone else.

Psychological changes

  • Agitation.
  • Anxiety.
  • Depression.
  • Hallucinations.
  • Inappropriate behavior.
  • Paranoia.
  • Personality changes.

How is dementia diagnosed?

Diagnosing dementia requires your doctor to do two things: first, determine the loss of cognitive function and two, assess what a person is still able to do. This requires a number of tests.

To start, your doctor will review your medical history and symptoms, and then conduct a physical examination. Because people with dementia might not recognize their own cognitive decline, your doctor will likely ask someone close to you about your symptoms as well.

Cognitive, neurological and neuropsychological tests

These tests examine both physical and mental capacity, including attention, balance, judgment, language skills, memory, orientation, reasoning, reflexes, senses, thinking skills, visual perception and other areas.

Brain scans

CT or MRI. These scans can check for evidence of stroke, bleeding, tumor or hydrocephalus.

PET scans. These can show patterns of brain activity and whether deposits of the amyloid or tau protein are in the brain.

Laboratory tests

Simple blood work is taken to look for physical reasons for decline in brain function, like vitamin B-12 deficiency or an underactive thyroid gland. Spinal fluid can also be looked at for infection, inflammation or markers of conditions like dementia.

Psychiatric evaluation

A mental health professional can determine whether depression or another mental health condition is contributing to your symptoms.

Who is at risk for developing dementia?

Dementia is predominantly associated with the elderly population, with a higher prevalence as age advances. Approximately 5% to 8% of individuals aged 65 and above experience dementia, and this percentage doubles every five years thereafter. Among those aged 85 and older, it is estimated that up to half may be affected by dementia.

According to the U.S. Centers for Disease Control and Prevention (CDC), approximately 5 million adults aged 65 or older in the U.S. currently have Alzheimer’s and related dementia. The CDC projects that by 2060, the number of people with dementia will rise to around 14 million, accounting for approximately 3.3% of the population.

Also, having a family history of dementia (particularly if your parents or siblings have been affected by Alzheimer’s), increases the likelihood of developing dementia yourself.

How is dementia treated?

Since there is no cure for most types of dementia, treatments mostly focus on ways to manage symptoms with the right blend of medications and therapies to give the best quality of life.


Doctors might prescribe these medications to temporarily improve dementia symptoms.

  • Cholinesterase inhibitors. These help increase levels of a chemical messenger linked to memory and judgment.
  • Memantine. Often prescribed along with a cholinesterase inhibitor, memantine governs the function of glutamate, a chemical messenger in the brain that impacts learning and memory.

Your doctor might prescribe additional medications that treat other symptoms or conditions, including agitation, depression, hallucinations, parkinsonism and sleep disturbances.


Your doctor might decide to treat your dementia symptoms with approaches that don’t use medication, including:

  • Occupational therapy. An occupational therapist can show you how to avoid falls and other accidents, deal with behavior and ready yourself for the progression of dementia.
  • Modifying the environment. For dementia patients, simpler is better. Reduce noise and clutter as much as possible to boost their focus and function.
  • Simplifying tasks. Make tasks as easy as possible to follow and focus on successful outcomes.

What are the most common types of dementia?

Primary dementia types

Alzheimer’s disease, the prevailing cause of dementia, accounts for 60 to 80 percent of all cases. It arises from distinct cerebral changes and primarily affects recent memory recall, progressing to encompass motor difficulties, speech impairments and alterations in personality. A notable risk factor is a family history, which increases the likelihood of developing Alzheimer’s by 10 to 30 percent.

Vascular dementia contributes to approximately 10 percent of dementia cases, and stems from cerebrovascular issues such as stroke or disrupted blood flow. Risk factors also include conditions like diabetes, hypertension and high cholesterol. Symptoms vary depending on the affected brain regions and tend to worsen with subsequent strokes or mini-strokes.

Lewy body dementia causes not only memory loss, but also motor and balance problems like stiffness or tremors. Individuals may experience changes in alertness, such as excessive daytime sleepiness, confusion or periods of fixed gaze. Sleep disturbances and visual hallucinations (seeing non-existent people, objects or shapes) are also common.

Fronto-temporal dementia predominantly affects personality and behavior due to its impact on specific cerebral areas. Individuals may exhibit uncharacteristic social behavior, make inappropriate remarks and neglect responsibilities at home or work. Language skills like speaking and comprehension may also be impaired.

Mixed dementia occurs when multiple types of dementia coexist at the same time, typically observed in individuals aged 80 and older. Identifying mixed dementia can be challenging as symptoms may be similar, overlap or present in varying degrees. Mixed dementia often progresses more quickly compared to singular dementia types.

Secondary dementia types

Dementia can also be caused by another disease or condition. The most common ones are:

Huntington’s disease, which is characterized by a breakdown in brain nerve cells leading to movement control problems, cognitive difficulties and personality changes.

Parkinson’s disease can also progress to dementia in its later stages, with symptoms such as cognitive impairment, hallucinations and speech problems.

Creutzfeldt-Jakob disease, a very rare infective brain disorder caused by abnormal proteins, which results in thinking and memory problems, communication difficulties and behavioral changes.

Wernicke-Korsakoff syndrome arises from a severe deficiency of vitamin B1 (thiamine), leading to brain bleeding in memory-related areas. It is commonly caused by alcohol use disorder, malnutrition or chronic infection. Symptoms include double vision, muscle coordination loss, and difficulties in information processing, learning and memory.

Traumatic brain injury, often seen in sports players (due to repeated blows to the head) and car accident survivors, which can cause dementia symptoms years later including memory loss, mood changes, slurred speech and headaches.

Can dementia be prevented?

While there is no direct prevention method for dementia, research has shown there are some practical steps you can take to reduce your risk factors for getting dementia. These include:

  • Attend check-ups. When you and your family members are screened regularly, there is a better chance that any abnormalities can be found and treated early.
  • Don’t drink or smoke. Avoiding these may prevent you from contracting respiratory illnesses, along with many other diseases.
  • Eat a healthy diet. Get the proper vitamins and nutrients in your diet from foods like leafy greens and berries.
  • Exercise. Even light exercise like walking or swimming can be beneficial.
  • Keep your brain engaged. Actively participate in puzzle-solving, play word games and do other mentally stimulating activities. These brain-intensive activities have the potential to postpone the onset of dementia.
  • Stay socially active. Engage in meaningful interactions with people, discuss current events, and keep your mind and heart actively involved in healthy social experiences.
  • Monitor blood pressure. Ensure your blood pressure is always at a healthy level and avoid high sodium foods.
  • Pay attention to your overall health. Go to the doctor when you experience a strange pain or something that concerns you.

Frequently asked questions (FAQs) about dementia

Is there a cure for dementia?

Although no cure has yet been identified for dementia, your doctor can offer treatments to slow its progression, ease your symptoms and help improve your quality of life.

Can dementia cause death?

Dementia does not directly cause death. However, as the disease progresses, it can significantly impact cognitive and physical functioning, leaving individuals vulnerable to complications such as infections, pneumonia or other serious medical conditions that can eventually be fatal.

Can dementia be seen on an MRI?

An MRI can help identify markers associated with mild cognitive impairment (MCI) and predict who may eventually develop dementia.

What is dementia with lewy bodies?

Lewy body dementia (LBD) adversely affects brain cells over time, causing a type of progressive dementia that deteriorates the ability to think. Over time it leads to a decline in cognitive abilities, visual hallucinations, movement and balance problems, fluctuations in alertness and sleep disturbances.

What's the difference between dementia and Parkinson's disease?

Parkinson’s disease is known more as a physical disorder that impacts movement. As it progresses, however, Parkinson’s disease can cause cognitive problems, including memory loss and dementia.

What’s the difference between dementia and Alzheimer’s disease?

Dementia is an umbrella term that encompasses a range of cognitive disorders characterized by memory loss and impairment in thinking and behavior. Alzheimer’s disease is the most common form of dementia, specifically affecting memory, thinking and behavior, and is responsible for the majority of dementia cases.

Does memory loss mean dementia is starting?

Various causes contribute to memory loss and they don’t always indicate dementia. Normal aging may bring mild memory changes without functional impairment. Dementia, however, is more severe and affects daily functioning and goes far beyond simple forgetfulness. Dementia is not a normal part of aging.

Is dementia hereditary?

While dementia can have genetic factors, it’s not always directly inherited. Some types of dementia (such as early-onset Alzheimer’s disease), have been found to have a strong genetic component, but other forms of dementia have complex causes involving a combination of genetic, environmental and lifestyle factors.

Why do dementia patients have trouble sleeping?

People with dementia tend to have problems sleeping, with up to half of patients with severe dementia experiencing sleep disturbances. As the dementia progresses, so too does the severity of their sleep disturbances.

One of the most common reasons why dementia patients have trouble sleeping is a phenomenon called “sundowning.” Taking place in the evening or during the night, people with dementia who are experiencing sundowning might feel confused, restless, agitated, anxious and aggressive.

Here are several additional reasons why people with dementia might have trouble sleeping at night:

  • Less of a need for sleep, which is common among older adults.
  • Changes in the body clock.
  • Disorientation.
  • Mental and physical exhaustion at the end of the day.
  • Reduced lighting and increased shadows, which can cause people with dementia to become confused and afraid.


Center for Disease Control and Prevention (CDC). What Is Dementia? (

National Institute of Aging (NIA). What Is Dementia? Symptoms, Types, and Diagnosis (

National Institute on Aging (NIA). What Is Dementia? (