Dementia

Dementia is a description of the state of a person’s mental function and not a specific disease.

Dementia entails a decline in mental function from a previously higher level that’s severe enough to interfere with daily living. A person with dementia has two or more of these specific difficultiesincluding a decline in:

• Memory.
• Reasoning.
• Language.
• Coordination.
• Mood.
• Behavior.

Dementia develops when the parts of your brain involved with learningmemorydecision-making or language are affected by infections or diseases. The most common cause of dementia is Alzheimer’s disease.

But other known causes of dementia include:

• Vascular dementia.
• Dementia with Lewy bodies.
• Frontotemporal dementia.
• Mixed dementia.
• Dementia due to Parkinson’s disease.
• Dementia-like conditions due to reversible causessuch as medication side effects or thyroid problems.

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

Dementia is a description of the state of a person’s mental function and not a specific disease. Dementia is an “umbrella category” describing mental decline that’s severe enough to interfere with daily living.

There are many underlying causes of dementiaincluding Alzheimer’s disease and Parkinson’s disease. Alzheimer’s disease is the most common underlying cause of dementia.

Who gets dementia?

Dementia is considered a late-life disease because it tends to develop mostly in people who are older.

About 5% to 8% of all people over the age of 65 have some form of dementiaand this number doubles every five years above that age. It’s estimated that as many as half of people 85 years of age and older have dementia.

The number of people age 65 and older who have Alzheimer’s disease and related dementias by race is:

• Blacks: 14%
• Hispanics: 12%
• Non-Hispanic whites: 10%
• American Indian and Alaska Natives: 9%
• Asian and Pacific Islanders: 8%

How common is dementia?

The U.S. Centers for Disease Control and Prevention (CDC) estimate that 5 million U.S. adults age 65 or older have Alzheimer’s and related dementia. By 2060the CDC projects that about 14 million people will have dementiawhich is about 3.3% of the population.

Alzheimer’s disease is the sixth leading cause of death in the U.S. and the fifth leading cause of death in Americans age 65 and older.

Does memory loss mean dementia is starting?

One common misbelief about memory loss is that it always means you or a loved one has dementia. There are many causes of memory loss. Memory loss alone doesn’t necessarily confirm a diagnosis of dementia.

It’s also true that some memory changes are normal as a person ages (some neurons in your brain naturally die as we age). Howeverthis type of memory loss isn’t functionally disabling; meaningit doesn’t interfere with daily life.

Dementia interferes with your ability to function. Dementia isn’t forgetting where you left your keys. A person with dementia can have situations like forgetting what keys are used for. Dementia isn’t a normal part of aging.

Are there different types of dementia?

Dementias can be divided into three groups:

• Primary (diseases and conditions in which dementia is the main illness).
• Secondary (dementia due to another disease or condition).
• Reversible dementia-like symptoms caused by other illnesses or causes.

Primary dementia

Types of primary dementia include:

• Alzheimer’s disease: This is the most common type of dementia. Two abnormal proteins build up in your brain: tau and amyloid proteins. These proteins disrupt communication between nerve cells in your brain. Nerve cells diestarting in one area and spreading as more nerve cells die in other areas. Symptoms include short-term memory lossconfusionpersonality and behavior changes. Trouble talkingremembering distant memories and issues with walking happen later in the disease. Alzheimer’s disease mainly affects adults who are older — up to 10% of those over age 65 and about 50% of people older than 85 have the disease. Family history is an important risk factor. Approximately 60% to 80% of people with dementia have this type.
• Vascular dementia: This is the second most common type of dementia. It’s caused by conditions such as strokes or atherosclerosiswhich block and damage blood vessels in your brain. Symptoms include memory problemsconfusion and trouble concentrating and completing tasks. The decline may appear suddenly (following a major stroke) or in steps (following a series of mini strokes). Risk factors include high blood pressurediabetes and high cholesterol levels. About 15% to 25% of people with dementia have vascular dementia.
• Lewy body dementia: This condition involves the buildup of clumps of proteins — called Lewy bodies — in your brain’s nerve cells. Lewy bodies damage nerve cells. Symptoms include movement and balance problemschanges in sleep patternsmemory lossplanning and problem-solving difficultiesand visual hallucinations and delusions. About 5% to 10% of dementias are Lewy Body dementia.
• Frontotemporal dementia (FTD): This dementia results from damage to the frontal and temporal lobes of your brain. The damage is caused by the buildup of abnormal proteins in these areas. It causes changes in social behaviorpersonalityand/or loss of language skills (speakingunderstanding or forgetting the meaning of common words) or motor coordination. FTD is a common cause of early dementiaoften occurring in people between the ages of 45 and 64. Between 5% and 6% of all dementias are FTD.
• Mixed dementia: This is a combination of two or more types of dementia. The most common combination is Alzheimer’s disease with vascular dementia. It’s most common in people 80 years of age and over. It’s often hard to diagnose because symptoms of one dementia may be more obvious and/or many symptoms of each type overlap. The decline is faster in people who have mixed dementia compared with those who only have one type.

Dementia due to other diseases and conditions

Other causes of dementia include:

• Huntington’s disease: A single defective gene causes this brain disorder. The disease causes a breakdown in your brain’s nerve cellswhich causes body movement control problemsas well as thinkingdecision-making and memory troubleand personality changes.
• Parkinson’s disease: Many people in the later stages of Parkinson’s disease develop dementia. Symptoms include trouble with thinking and memoryhallucinations and delusionsdepression and trouble with speech.
• Creutzfeldt-Jakob disease: This rare infective brain disease affects about only 1 in 1 million people. An abnormal protein in your brain called prions causes the disease. These prions clump together and cause nerve cell death in your brain. Symptoms include problems with thinkingmemorycommunicationplanning and/or judgmentconfusionbehavior changesagitation and depression.
• Wernicke-Korsakoff syndrome: This brain disorder is caused by a severe thiamine (vitamin B1) deficiency. This can result in bleeding in key areas related to memory in your brain. It’s most commonly caused by alcohol use disorder but can also be due to malnutrition and chronic infection. Symptoms include double visionloss of muscle coordinationand difficulty processing informationlearning new skills and remembering things.
• Traumatic brain injury: Repeated blows to your head can cause this injury. It’s most often seen in football playersboxerssoldiers and people who’ve had a vehicle accident. Dementia symptomswhich appear years laterinclude memory lossbehavior or mood changesslurred speech and headaches.

Dementias due to reversible causes

Some conditions can cause dementia-like symptoms that can be reversed with treatmentincluding:

• Normal pressure hydrocephalus (NPH): This condition happens when cerebrospinal fluid (CSF) builds up in your brain’s spaces (ventricles). The excess buildup harms your brain. NPH can be caused by a brain infectionbrain injurybrain bleed or previous brain surgery. Symptoms include poor balanceforgetfulnesstrouble paying attentionmood swingsfrequent falls and loss of bladder control. Your healthcare provider can drain excess fluid through the surgical placement of a shunt (tube).
• Vitamin deficiency: Not getting enough vitamin B1B6B12 cooper and vitamin E in your diet can cause dementia-like symptoms.
• Infections: Infections that can cause dementia-like symptoms include HIV infectionsyphilis and Lyme disease. Symptoms reported with COVID-19 infection include “brain fog” and acute delirium. Because of the inflammation and stroke risk seen with COVID-19 infectionboth short- and long-term cognitive effects are being investigated. Urinary tract infections (UTIs) and infections in your lungs in the elderly can also result in dementia-like symptoms. Other central nervous system infections and brain infections caused by fungibacteria and parasites can also cause cognitive symptoms.
• Metabolic and endocrine conditions: Conditions that can mimic dementia include Addison’s diseaseCushing’s diseaselow blood sugar (hypoglycemia) exposure to heavy metals (like arsenic or mercury)high calcium levels (hypercalcemiaoften due to hyperparathyroidism)liver cirrhosis and thyroid problems.
• Medication side effects: Some medicationsin some peoplecan mimic dementia symptoms. These include sleeping pillsanti-anxiety drugsantidepressantsanti-seizure drugsantiparkinson drugsnonbenzodiazepine sedativesnarcotic pain relieversstatins and others. Ask your healthcare provider to review your medications if you have any dementia-like symptoms.
• Other causes: Other causes of dementia-like symptoms include brain tumors and subdural hematomas (brain bleeds between your brain’s surface and the covering over your brain).

What are the symptoms of dementia?

Early symptoms of dementia include:

• Forgetting recent events or information.
• Repeating comments or questions over a very short period.
• Misplacing commonly used items or placing them in unusual spots.
• Not knowing the seasonyear or month.
• Having difficulty coming up with the right words.
• Experiencing a change in moodbehavior or interests.

Signs that dementia is getting worse include:

• Your ability to remember and make decisions further declines.
• Talking and finding the right words becomes more difficult.
• Daily complex taskssuch as brushing your teethmaking a cup of coffeeworking a TV remotecooking and paying bills become more challenging.
• Lessening of rational thinking and behavior and your ability to problem-solve.
• Sleeping pattern changes.
• Increases or worsening of anxietyfrustrationconfusionagitationsuspiciousnesssadness and/or depression.
• Needing more help with activities of daily livingsuch as groomingtoiletingbathing and eating.
• Experiencing hallucinations (seeing people or objects that aren’t there).

These symptoms are general symptoms of dementia. Each person diagnosed with dementia has different symptomsdepending on what area of their brain is damaged. Additional symptoms and/or unique symptoms occur with specific types of dementia.

What are the causes of dementia?

Dementia is caused by damage to your brain. Dementia affects your brain’s nerve cellswhich destroys your brain’s ability to communicate with its various areas. Dementia can also result from blocked blood flow to your braindepriving it of needed oxygen and nutrients. Without oxygen and nutrientsbrain tissue dies.

Damage to your brain results in different symptomsdepending on the area of your brain affected. Some dementias aren’t reversible and will worsen over time. Other dementias are due to other medical conditions that also affect your brain. Another group of health issues can result in dementia-like symptoms. Many of these conditions are treatableand the dementia symptoms are reversible.

All of the possible causes of dementia are discussed in the question“Are there different types of dementia?”

How is dementia diagnosed?

Confirming a diagnosis of dementia can be difficult. Many diseases and conditions can cause or lead to dementia. In additionmany of its symptoms are common to many other illnesses.

Your healthcare provider will:

• Ask about the course of your symptoms.
• Ask about your medical history.
• Review your current medications.
• Ask about your family history of disease including dementia.

They may also order testsincluding laboratory testsimaging tests and neurocognitive tests (thinking tests).

Neurologists and geriatricians may assist in making the diagnosis of dementia.

Laboratory tests

Laboratory tests rule out other diseases and conditions as the cause of dementiasuch as infectioninflammationunderactive thyroid and vitamin deficiency (especially B12).

Sometimeshealthcare providers order cerebrospinal fluid tests to evaluate autoimmune conditions and neurodegenerative diseasesif warranted.

Imaging tests

Your healthcare provider may order the following imaging tests of your brain:

• Computed tomography (CT) and magnetic resonance imaging (MRI): CT uses X-rays and a computer to show detailed images of your brain. MRI uses magnetsradio frequencies and a computer to create detailed images of your brain. These imaging tests look for evidence of strokebleedingtumors and fluid on your brain.
• FDG-PET scan: This is a special type of brain scan that aids in determining brain function and cognitive decline by the pattern of how a type of glucose is absorbed by brain tissueand is sometimes needed in specific diagnoses.

Neurocognitive testing

During neurocognitive testingyour healthcare provider uses written and computerized tests to evaluate your mental abilitiesincluding:

• Problem solving.
• Learning.
• Judgment.
• Memory.
• Planning.
• Reasoning.
• Language.

Psychiatric evaluation

A mental health professional may check for signs of depressionmood changes or other mental health issues that might cause memory loss.

Is dementia treatable?

Firstit’s important to understand the terms “treatable,” “reversible” and “curable.” All or almost all forms of dementia are treatablein that medication and other measures can help manage your symptoms. Howevermost types of dementia can’t be cured or reversedand treatments provide only modest benefits.

Fortunatelysome types of dementialike those brought on by treatable causesmay be successfully reversed. These dementia-like symptoms are caused by:

• Side effects of medicationsillicit drugs or alcohol.
• Tumors that can be removed.
• Subdural hematoma (a buildup of blood beneath the outer covering of your brain that’s caused by a head injury).
• Normal pressure hydrocephalus (a buildup of cerebrospinal fluid in your brain).
• Metabolic disorderssuch as a vitamin B12 deficiency.
• Hypothyroidisma condition that results from low levels of thyroid hormones.
• Hypoglycemia (low blood sugar).
• Depression.

Dementias that aren’t reversible may still partially respond to medications that treat memory loss or behavior problems. These dementias include:

• Alzheimer's disease.
• Multi-infarct (vascular) dementia.
• Dementias associated with Parkinson's disease and similar disorders.
• AIDS dementia complex.
• Creutzfeldt-Jakob disease.

What medications are available to manage dementia?

Drugs approved for the most common form of dementiaAlzheimer’s diseaseinclude:

• Cholinesterase inhibitorsincluding donepezil (Aricept®)rivastigmine (Exelon®) and galantamine (Razadyne®).
• NMDA receptor antagonist memantine (Namenda®).
• Anti-amyloid antibody aducanumab (Aduhelm®).

Healthcare providers use these drugs to treat people with some of the other forms of dementia.

Cholinesterase inhibitors and the NMDA receptor antagonist affect different chemical processes in your brain. Both drug classes have been shown to provide some benefit in improving or stabilizing memory function in some people with dementia.

Cholinesterase inhibitors manage the chemicals in your brain that allow messages to be sent between brain cellswhich is needed for proper brain function. (Connections are lost as brain cells die when dementia worsens.) Memantine works similarly to cholinesterase inhibitors except it works on a different chemical messenger and helps the nerve cells survive longer.

Aducanumab targets amyloid proteinswhich build up into the plaques seen in the brains of people with Alzheimer’s disease.

Although none of these drugs appear to stop the progression of the underlying diseasethey may slow it down.

If other medical conditions are causing dementia or co-exist with dementiahealthcare providers prescribe the appropriate drugs used to treat those specific conditions. These other conditions include sleeping problemsdepressionhallucinations and agitation.

Is there a cure for dementia?

Unfortunatelythere isn’t a cure for the most common types of dementia. Currentlyapproved medications canat bestslow the decline.

What are the possible complications of dementia?

Your brain controls all of your body’s functions. When your brain functions declineyour overall health is eventually at risk. Many illnesses and conditions can happen as a result of having dementia.

Possible complications of dementia include:

• Dehydration and malnutrition.
• Bedsores (pressure ulcers).
• Injuries and bone fractures from falls.
• Strokes.
• Heart attacks.
• Kidney failure.
• Pneumonia and aspiration pneumonia (food particles are inhaled into your lung and cause infection).
• Sepsis (infection).

What can I expect if I have dementia?

Getting a diagnosis of dementia is certainly difficult to hear. Several types of dementia aren’t reversible. Others are a side effect of other serious diseases. Some dementia-like symptoms are due to conditions that can be treated and reversed.

Your healthcare teamwhich will probably include a neurologist and/or a geriatric-psychiatrist or a geriatricianwill order the needed tests to make the correct diagnosis. The medications available today focus on slowing the decline.

The goal is to maintain your or your loved one’s quality of life. Some people with Alzheimer’s dementia can live up to two decadesbut each person has their own unique course. Researchers continue learning about the mechanisms that cause dementia and testing different methods to slowand somedayhopefullycure this disease.

Can dementia be prevented?

Although dementia can’t be preventedliving a health-focused life might reduce risk factors for certain types of dementia.

Keeping blood vessels clear of cholesterol buildupmaintaining normal blood pressuremaintaining healthy blood sugar levelsstaying at a healthy weight — basicallystaying as healthy as you can — can keep your brain fueled with the oxygen and nutrients it needs to function at its highest possible level. Specific healthful steps you can take include:

• Stop smoking.
• Follow a Mediterranean dietwhich is one filled with whole grainsvegetablesfruitsfish and shellfishnutsbeansolive oil and only limited amounts of red meats.
• Exercise. Get at least 30 minutes of exercise most days of the week.
• Keep your brain engaged. Solve puzzlesplay word games and try other mentally stimulating activities. These activities may delay the start of dementia.
• Stay socially active. Interact with peoplediscuss current eventsand keep your mindheart and soul engaged.

What are the risk factors for dementia?

Risk factors for dementia include:

• Age: This is the strongest risk factor. Your chance of dementia increases as you age. Most cases affect people over the age of 65.
• Family history: If you have biological parents or siblings with dementiayou’re more likely to develop dementia.
• Down syndrome: If you have Down syndromeyou’re at risk of developing early-onset Alzheimer’s disease by middle age.
• Poor heart health: If you have high cholesterol levelshigh blood pressureatherosclerosis or smokeyou increase your risk of dementia. These health problemsas well as diabetesaffect your blood vessels. Damaged blood vessels can lead to reduced blood flow and strokes.
• Race and ethnicity: If you’re a Black personyou have twice the risk as a white person for developing dementia. If you’re a Hispanic personyou’re 1.5 times more likely than a white person to develop dementia.
• Brain injury: If you’ve had a severe brain injuryyou’re at a higher risk for dementia.

When should I see my doctor about dementia?

Make an appointment with your healthcare provider if you or your friends and family see changes in:

• Your memory.
• Your mental functioning.
• Your ability to perform everyday tasks.
• Your behavior.
• Your personality.

What happens to a person’s brain and body as dementia gets worse?

Unfortunatelymany types of dementia are conditions that worsen over time. When your brain doesn’t get the nutrients and oxygen it needsor “junk” (abnormal proteins) blocks needed communication between the nerve cells of the brainyour brain tissue begins to die.

Alzheimer’s disease and other types of dementia usually begin with memory loss or lapses in judgment — things that can be lived with for a while. As you lose more and more brain functionfunctions vital to life begin to be affected. Vital functions include breathingdigestionheart rate and sleep.

In the late stages of dementiapeople can’t perform the tasks needed to keep their bodies alive. Brain damage and muscle weakness no longer allow even simpleneeded movements. You can’t communicatewalktalkcontrol your bladder or bowelsfeed yourselfor chew or swallow food without help.

When you can’t care for yourselfmove abouteat or drink enough to keep yourself hydrated and nourishedplus have mental declineyou leave yourself vulnerable to other illnesses. Pneumonia is one of these commonly seen illnesses in people with dementia. With a now frail bodya person may not be able to fight infections or even benefit from medication. The person’s pain and discomfort may outweigh treatment options that can only offer a short-term benefit.

At this pointmany families choose hospice for end-of-life care. Hospice provides comfort carewith a focus on your quality of life over life-extending measures. Many people who pass away from a dementia-related condition don’t have that listed on their death certificate. This is because the complication from which they die — pneumoniafor example — is listed instead. Another reason may be that many people were never officially diagnosed with a dementia condition before they passed away.

What's the life expectancy of a person with dementia?

There’s no easy way to answer this question. Dementia is an “umbrella” term that covers the many different types of underlying neurodegenerative diseases.

Each type of neurodegenerative disease has its own unique pattern and development in each person. Alsoeach person has a unique health profile. Some people may be relatively healthy and others may have several co-existing health issues. All of these factors play a role in the pace of decline in a person with dementia.

To answer more broadlyAlzheimer’s is the most common type of dementia. The average lifespan after the earliest symptoms is eight years. Howeversome people have lived as long as 20 years after an Alzheimer’s disease diagnosis.

Are there stages of dementia?

No national dementia-related organizations define dementia by numerical stages. The Alzheimer’s Association doeshoweverdefine three stages of Alzheimer’s disease. Alzheimer’s disease dementia is the most common type of dementia. Some of the symptoms in these three stages are the same as symptoms for many of the forms of dementia.

Early-stage Alzheimer’s disease (mild)

People in the mild stage of Alzheimer’s disease are still able to function on their own. They may still drivego to work and socialize. Some changes are happening that may or may not be noticed by the person with Alzheimer’s diseasebut may be noticeable by close friends and family members.

Difficulties may include:

• Trouble remembering a person’s name after being introduced.
• Losing or misplacing multiple objects.
• Having a hard time coming up with the right word consistently.
• Trouble planningorganizingmanaging or completing tasks.
• Consistently forgetting what you just read.

Middle-stage Alzheimer’s disease (moderate)

People in the middle stage of Alzheimer’s disease can be in this stage for many years. They can take part in everyday activities with help. Symptoms are more obvious.

Difficulties may include:

• Confusion about what year/season it is or where you are.
• Forgetting events and being unable to recall personal history (phone numberaddressthe college you attendedetc.).
• Changes in personalitymood and behaviorsuch as becoming suspiciousdelusional and performing compulsiverepetitive actions.
• Changes in day/night sleeping patterns.
• Controlling your bladder and/or bowels.
• Wearing clothes for the wrong season or occasion.
• Wandering and becoming lost.

Late-stage Alzheimer’s disease (severe)

People in the late stage of Alzheimer’s disease can’t carry on conversationslose awareness of what’s going on around them and can’t control their movement.

Difficulties may include:

• Trouble communicatingwhich may include only being able to say a few words or phrases.
• Trouble walking.
• Trouble swallowing.
• Being more prone to infectionsespecially pneumonia.
• Requiring 24-hour assistance with care.