Dementia

Overview

Dementia is the loss of thinking, remembering, and reasoning skills to the point where it gets in the way of everyday life. Some people with dementia cannot control their emotions, and their personalities may change.

When it is just starting to affect a person, dementia symptoms can be mild. As symptoms get worse, a person may need increasing help from others for activities of daily living, such as eating or dressing.

Although there are no cures for the different types of dementia, some treatments may help manage symptoms. Some newer treatments may slow Alzheimer’s disease progression in certain people. Many drug candidates for Alzheimer’s and other dementias are currently being tested in clinical trials.

Signs and Symptoms

Signs and symptoms can vary depending on the type of dementia, but may include:

• Memory loss, poor judgment, and confusion
• Difficulty speaking, understanding thoughts, or reading and writing
• Wandering and getting lost in a familiar neighborhood
• Trouble handling money and paying bills
• Repeating questions
• Using unusual words to refer to familiar objects
• Taking longer to complete normal daily tasks
• Losing interest in normal daily activities or events
• Seeing things that are not there (hallucinations) or having other changes in perception or behavior
• Acting impulsively
• Changes in empathy, personality, or social behavior
• Problems with balance and movement
• Experiencing agitation, restlessness, irritability, and aggression
• Problems with sleep

Recognizing symptoms in people with pre-existing intellectual and developmental disabilities can be especially difficult.

Talk with a doctor if you notice any changes in memory or thinking that concern you.

Diagnosis

Getting an early diagnosis can be helpful. This is especially true as some medical conditions (for example, infections, vitamin deficiencies, thyroid imbalances, medication side effects, or other) can cause symptoms that look like dementia but may be treatable or reversible.

Doctors may use a combination of methods to diagnose dementia, such as:

• Medical and family history review: Doctors ask about when symptoms began, changes in behavior, family history of dementia, and medicines that might cause or worsen symptoms.
• Physical exam: A physical exam measures blood pressure and other vital signs.
• Cognitive and neurological tests: These tests check memory, problem solving, language skills, math skills, balance, sensory response, and reflexes.
• Brain scans: Scans can identify loss of nerve cells, accumulation of abnormal proteins, strokes, tumors, and other problems. Common scans include:
  • Computed tomography (CT) scans use X-rays to produce images of the brain.
  • Magnetic resonance imaging (MRI) scans use magnetic fields and radio waves to produce detailed images.
  • Positron emission tomography (PET) scans use radiation to show brain activity.
• Psychiatric evaluation: This helps determine if depression or another mental health condition is causing symptoms.
• Genetic tests: In some rare families, genetic testing may help identify inherited forms of dementia. However, for most people, genetic testing is not routinely needed. Some genes may raise risk, but they do not by themselves predict whether a person will develop dementia.
• Cerebrospinal fluid tests: Doctors collect cerebrospinal fluid through a procedure called a lumbar puncture, also called a spinal tap. Measuring protein levels in CSF may help diagnose Alzheimer’s or other types of dementia.
• Blood tests: Doctors can order blood tests during a diagnostic evaluation to measure Alzheimer’s-related biomarkers, such as beta-amyloid and tau. Depending on the results and the person’s symptoms, a clinician may recommend confirmatory testing (such as cerebral spinal fluid tests or brain imaging (e.g. positron emission tomography (PET)). Blood test results require clinician interpretation and should not be used alone to diagnose Alzheimer's disease or a related dementia..

Who Can Diagnose Dementia?

Visiting a primary care doctor is often the first step. Neurologists, doctors who specialize in disorders of the brain and nervous system, are often consulted to diagnose dementia. Geriatric psychiatrists, neuropsychologists, and geriatricians may also be able to diagnose dementia.

If a specialist cannot be found in your community, contact the nearest medical school neurology department for a referral.

Causes and Risk Factors

Dementia symptoms can happen when once-healthy nerve cells in the brain stop working, lose connections with other brain cells, and die. While it’s normal to have some nerve cell loss as people age, people with dementia experience far greater.

Aside from rare forms of dementia caused by genetic mutations, the cause or causes of dementia are unknown (or unclear). The specific symptoms of different dementias depend on the type and location of brain changes:

Alzheimer’s disease involves abnormal buildups of proteins in the brain called amyloid plaques and tau tangles.

Frontotemporal dementia is the most common form of dementia in people younger than 60. It is linked to abnormal accumulation of the proteins tau or TDP-43 within brain cells.

Lewy body dementia involves abnormal deposits of the protein alpha-synuclein, called Lewy bodies, in the brain. It typically begins after age 50.

Vascular dementia is caused by conditions that damage blood vessels in the brain or interrupt the flow of blood and oxygen to the brain. Risk factors include stroke, high blood pressure, diabetes, and high cholesterol.

Limbic-predominant age-related TDP-43 encephalopathy (LATE) is a recently described brain disease that can cause symptoms similar to Alzheimer’s. It involves abnormal clusters of a protein called TDP-43 and may occur along with Alzheimer’s-related brain changes. It is most common in people over the age of 80, and studies of brains examined after death suggest it may be fairly common in this age group. Currently, this form of dementia cannot be definitively diagnosed in living people.

Mixed dementia is a combination of two or more types of brain pathologies. Research has found that it’s common in older adults with dementia to have more than one type of brain change happening at the same time. For example, vascular damage commonly co-occurs with Alzheimer’s and Lewy body brain changes.

Other conditions that can cause dementia or dementia-like symptoms include:

• Normal pressure hydrocephalus: An abnormal buildup of fluid in the brain
• Creutzfeldt-Jakob disease: A rare brain disorder
• Huntington disease: An inherited, progressive brain disease
• Chronic traumatic encephalopathy (CTE): Diagnosed after death and caused in part by repeated traumatic brain injury
• HIV-associated dementia: A rare disease that occurs when HIV spreads to the brain.
• Wernicke-Korsakoff Syndrome: Heavy alcohol use over a long period of time causes this condition due to thiamine deficiency
• Head injury: Such as a concussion from a fall or accident
• Emotional problems: Such as stress, anxiety, and depression
• Delirium: A sudden state of confusion and disorientation

Medical conditions such as tumors, vitamin deficiencies, medicine side effects, or problems with the thyroid, kidney, or liver can also cause serious memory problems that look like dementia. Some of these causes can be treated or even reversed.

Risk Factors

The main risk factors for dementia are age and genes, although certain lifestyle factors also play a contributing role. 

Age is the biggest known risk factor for developing dementia. Most people with Alzheimer’s develop symptoms when they are 65 or older. However, some people develop dementia earlier (early-onset) or later in life.

How Is Dementia Different from Normal Aging?

Here are some key differences between dementia and normal aging:

Genetics can also play a role in the development of dementia. In most cases, dementia does not have a single genetic cause. Instead, it is likely influenced by multiple genes combined with lifestyle and environmental factors.

One well-known gene that influences dementia risk is the APOE gene. One form of this gene increases a person’s risk of developing Alzheimer's, Lewy body dementia, and vascular dementia. The gene linked to an earlier age when symptoms begin, but the size of this effect can differ across ancestry groups. APOE is a risk factor, not a diagnosis. Counseling is recommended before/after testing and results do not reliably predict if/when disease occurs.

However, there are rare variants in three genes that are known to cause Alzheimer’s disease:

• APP on chromosome 21
• PSEN1 on chromosome 14
• PSEN2 on chromosome 1

A child whose biological parent carries one of these variants has a 50/50 chance of inheriting it.

People with Down syndrome (a genetic disease), have a higher risk of developing Alzheimer’s disease earlier in life. About half of people with Down syndrome will develop Alzheimer’s, with symptoms appearing in their 50s or 60s.

Additionally, an inherited dementia is FTD (C9ORF72, MAPR, GRN genetic mutations). CADASIL is also an inherited genetic condition that leads to vascular dementia.

Other risk factors for dementia include:

• High blood pressure
• Stroke
• Diabetes
• Obesity
• Heavy alcohol use
• Smoking
• Head injury
• Hearing loss
• Depression
• Physical inactivity
• Social isolation
• Poor sleep
• Lack of mental stimulation

Prevention Guidance

Researchers cannot yet say for certain what, if anything, can prevent dementia. However, leading a healthy lifestyle may help reduce risk factors. Research has shown that interventions that combine physical activity, improved nutrition, cognitive and social challenge, and health monitoring may improve cognition in older adults at risk of dementia.

• Manage chronic health conditions such as high blood pressure, diabetes, and high blood cholesterol.
• Stay physically active. Federal guidelines recommend that all adults get at least 150 minutes (2.5 hours) of physical activity each week.
• Eat a healthy diet. A healthy, balanced diet includes fruits and vegetables, whole grains, lean meats, fish, and poultry, and low-fat dairy products.
• Get enough sleep, generally seven to nine hours each night.
• Stay socially connected with family, friends, and neighbors through social activities and community programs.
• Keep your mind engaged through cognitive training and meaningful activities.
• Limit or avoid alcohol.
• Quit smoking if you currently smoke.
• Treat hearing or vision loss.
• Get recommended health screenings and check in regularly with a healthcare provider.

Treatment and Management

Although there are currently no cures for the different types of dementia, there are some treatments that may help manage symptoms. Some newer treatments may slow dementia progression in certain people. There are also medicines that may temporarily improve or stabilize memory and thinking skills in some people. Always consult with a doctor, as some medicines may make symptoms worse.

One class of drugs, called cholinesterase inhibitors (such as donepezil, rivastigmine, and galantamine), can temporarily improve or stabilize memory and thinking skills in some people. The drug memantine may be combined with a cholinesterase inhibitor for added benefits.

Antidepressants, antipsychotics, and anti-anxiety drugs may be helpful for some people with Alzheimer’s who experience sleeplessness, depression, anxiety, or agitation. However, experts agree that these medicines should be used only after other strategies to promote physical and emotional comfort have been tried.

Some conditions that are associated with dementia symptoms may be treatable or even reversible with treatment. For example, normal pressure hydrocephalus often resolves with treatment. Nutritional deficiencies of vitamins B1 and B12 can also be reversed with treatment.

Treatment for dementia is not only about medicines. Care may also include physical activity, speech or occupational therapy, safety planning, treatment for sleep issues, support for caregivers, and help with daily activities. A team of specialists — doctors, nurses, and speech, physical, and other therapists — familiar with these disorders can help guide care. Therapists can help with maintaining physical movement, address speech and swallowing issues, and help people learn new ways to handle loss of skills with everyday tasks.

Living With Dementia

In the early stages of cognitive decline and dementia, it may be possible for people to continue with their everyday activities. As symptoms progress, people will need to adopt new strategies to help adjust. It can also be helpful to plan ahead by deciding what happens if and when symptoms become more severe. Families may need to talk about driving, home safety, managing medicines, finances, legal documents, and future care preferences. See the Community Support section below for resources about more extensive information about immediate and long-term planning.

Tips For Daily Life

• Follow a daily routine.
• Plan tasks, make to-do lists, and use memory tools such as calendars and notes.
• Put your wallet or purse, keys, phone, and glasses in the same place each day.

Find Clinical Trials

Clinical trials uncover better ways to prevent, diagnose, treat, and understand diseases and conditions. To ensure results apply to everyone, volunteers of all ages, sexes, and backgrounds, including both healthy individuals and those with specific medical conditions, are needed. Find clinical trials on dementia.

Alzheimers.gov also has a section on learning more about clinical trials on Alzheimer's disease and how to find them.

Participation in a clinical trial is voluntary. Before joining, ask the study team about possible risks, benefits, costs, time commitments, and other care options.

Find Treatment

A primary care doctor is often the first person to talk with about changes in memory, thinking, movement, or behavior. If needed, the doctor may refer you to a specialist such as a neurologist, geriatrician, psychiatrist, or memory clinic. Your primary care doctor can help you find a specialist.

If a specialist cannot be found in your community, contact the nearest medical school neurology department for a referral. A medical school hospital may also have a dementia clinic that provides expert evaluation.

Finding Support as a Caregiver

Caring for a person with dementia can have significant physical, emotional, and financial costs. Becoming well-informed about the disease is one important long-term strategy. Good coping skills, a strong support network, and respite care may help caregivers handle the stress of caring for a loved one with dementia. Some caregivers have found that joining a support group is a critical lifeline. Many dementia non-profit organizations sponsor in-person and online support groups.

Caregivers should talk with their own healthcare provider if stress, sleep problems, depression, or anxiety begin affecting their health.

You can find more information about dementia at:

• Alzheimers.gov has information and resources on Alzheimer’s and related dementias from across the federal government.
• Alzheimer’s Association
• Alzheimer’s Foundation of America
• Eldercare Locator is a service of the Administration for Community Living to connect you to services for older adults and their families.
• Lewy Body Dementia Association
• Association for Frontotemporal Degeneration (AFTD)
• McKnight Brain Research Foundation

Note: This resource list is for informational purposes only. It is not comprehensive, and an organization’s inclusion does not constitute an endorsement by NIH.  

Research Information

The National Institutes of Health (NIH) is the largest public funder of biomedical research in the world. NIH invests most of its budget in medical research seeking to enhance life and to reduce illness and disability. NIH-funded research has led to breakthroughs and new treatments helping people live longer, healthier lives, and building the research foundation that drives discovery.  

NIH supports research on the causes, diagnosis, and treatment of dementias. This research has informed the development of new treatments and risk reduction approaches for Alzheimer's and related dementias.

Researchers have connected brain changes to certain forms of dementia and are studying why these changes happen in some people but not others. Scientists are also investigating how the disease processes in different forms of dementia start and influence each other. Further knowledge about the underlying causes of dementia will help researchers develop personalized prevention, treatment, and care strategies.

NIH-designated Alzheimer’s Disease Research Centers (ADRCs) serve as a national resource for research on the nature of Alzheimer’s disease (AD) and AD-related dementias (ADRD) and the development of more effective approaches to prevention, diagnosis, care, and therapy. They create shared resources that support dementia-relevant research.

Find NIH-funded research projects using NIH RePORTER, a searchable database of current and past research projects supported by NIH and other federal agencies.  

Brain Donation

Sometimes, a person with dementia, after discussing the option with their loved ones, will decide to donate their brain after they die. Brain donation is voluntary and ensures anonymity of the donor. Brain donation helps researchers study brain disorders such as Alzheimer’s disease and related dementias. When donating as part of a research study or to the NIH NeuroBioBank, there is no cost to the family for the donation and an autopsy report.