Alzheimer’s Disease and Other Dementias

Being a caregiver for someone with Alzheimer’s Disease or other dementias is challenging! In this education module you will find high-level information about the most common dementias; be sure to check out our FAQ section for answers to common questions

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Dementia is not a specific illness but a syndrome or group of symptoms which causes memory problems affecting everyday life. Dementia has a gradual onset and get progressively worse. The burden of Alzheimer’s disease and related dementias in 2014 was 5 million people, which is 1.6 percent of the U.S. population in 2014—319 million people. This burden is projected to grow to 13.9 million, nearly 3.3 percent of the population in 2060–417 million people.

An estimated 5% of people over age 65 and 20% of those over 85 have some form of dementia. Alzheimer’s disease accounts for 60% of all cases of dementia with 15-20% caused by strokes (cerebrovascular dementia) and 15-20% resulting from other neuro-psychological disorders, i.e. Parkinson’s disease and Huntington’s disease.

The most common types of dementia:

  • Alzheimer’s disease
    This is the most common cause of dementia, accounting for 60 to 80 percent of cases. It is caused by specific changes in the brain. The trademark symptom is trouble remembering recent events, such as a conversation that occurred minutes or hours ago, while difficulty remembering more distant memories occurs later in the disease. Other concerns, like difficulty with walking or talking or personality changes, also come later. Family history is the most important risk factor. Having a first-degree relative with Alzheimer’s disease increases the risk of developing it by 10 to 30 percent.
  • Vascular dementia
    About 10 percent of dementia cases are linked to strokes or other issues with blood flow to the brain. Diabetes, high blood pressure and high cholesterol are also risk factors. Symptoms vary depending on the area and size of the brain impacted. The disease progresses in a step-wise fashion, meaning symptoms will suddenly get worse as the individual gets more strokes or mini-strokes.
  • Lewy body dementia
    In addition to more typical symptoms like memory loss, people with this form of dementia may have movement or balance problems like stiffness or trembling. Many people also experience changes in alertness, including daytime sleepiness, confusion or staring spells. They may also have trouble sleeping at night or may experience visual hallucinations (seeing people, objects or shapes that are not actually there).
  • Fronto-temporal dementia
    This type of dementia most often leads to changes in personality and behavior because of the part of the brain it affects. People with this condition may embarrass themselves or behave inappropriately. For instance, a previously cautious person may make offensive comments and neglect responsibilities at home or work. There may also be problems with language skills like speaking or understanding.
  • Creutzfelkt-Jakob disease
    This type of dementia causes decline in thinking and reasoning as well as involuntary muscle movements, confusion, difficulty walking and mood changes. Getting worse unusually fast, this type of dementia is caused when prion protein folds into an abnormal shapes that destroy brain cells. 
    Mixed dementia. Sometimes more than one type of dementia is present in the brain at the same time, especially in people aged 80 and older. For example, a person may have Alzheimer’s disease and vascular dementia. It is not always obvious that a person has mixed dementia since the symptoms of one type of dementia may be most prominent or may overlap with symptoms of another type. Disease progression may be faster than with one kind of dementia.
    Reversible causes. People who have dementia may have a reversible underlying cause such as side effects of medication, increased pressure in the brain, vitamin deficiency, and thyroid hormone imbalance. 

Less common forms of dementia include Down Syndrome and Alzheimer’s Disease, Huntington’s Disease, Normal Pressure Hydrocephalus, Posterior Cortical Atrophy, Parkinson’s Disease Dementia, and Korsakoff Syndrome.

Besides Alzheimer’s and dementia, there are several other brain conditions that can cause problems with thinking, memory and behavior. These include: 

  • Mild cognitive impairment (MCI) is an early stage of memory loss or other cognitive ability loss (such as language or visual/spatial perception) in individuals who maintain the ability to independently perform most activities of daily living. This is often the first diagnosis given by primary care doctors who may not do rigorous testing at that point.
  • Chronic traumatic encephalopathy (CTE) is a progressive and fatal brain disease associated with repeated traumatic brain injuries (TBIs), including concussions and repeated blows to the head. It is also associated with the development of dementia. Studies have shown that people who experience TBI in early to midlife are two to four times more at risk of developing dementia in late life.  CTE is being studied in professional athletes, primarily football players.
  • Traumatic brain injury (TBI) results from an impact to the head that disrupts normal brain function. Traumatic brain injury may affect a long-term cognitive abilities, including learning and thinking skills, reduced ability to function, and changes in emotional health. Falls are the most common cause of traumatic brain injury. 

Alzheimer’s Disease

Alzheimer’s disease is an illness of the brain that causes nerve cells in the brain to die. It results in disrupted memory, thinking and functioning. While everyone who has Alzheimer’s disease has dementia, not everyone who has dementia has Alzheimer’s disease. The only definite diagnosis for Alzheimer’s disease is finding plaques and tangles in the brain during autopsy. There is a somewhat greater risk for people with a family history of the disease. Race or ethnicity does not seem to be a factor. To learn more, visit The Alzheimer’s Association’s website.

Diagnosis of dementia or Alzheimer’s is based on a range of tests:

  • Learn about: Diagnostic Criteria and Guidelines
  • A complete medical history includes information about the person’s general health, past medical problems, and any difficulties the person has carrying out daily activities.
  • Medical tests – such as tests of blood, urine, or spinal fluid – help the doctor find other possible diseases causing the symptoms.
  • Neuropsychological tests measure memory, problem solving, attention, counting, and language.
  • Brain scans allow the doctor to look at a picture of the brain to see if anything does not look normal.

Here are the ten warning signs of Alzheimer’s disease:

  1. Memory loss 
  2. Difficulty performing familiar tasks
  3. Problems with language
  4. Disorientation to time and place
  5. Poor or decreased judgment
  6. Problems with abstract thinking
  7. Misplacing things
  8. Changes in mood or behavior
  9. Changes in personality
  10. Loss of initiative

There are three main stages of Alzheimer’s disease:

Mild – 

  • Often looks and acts normal
  • Short-term memory fades, making it difficult to learn new things
  • Speech becomes slightly impaired
  • Hygiene can be neglected, and judgment hindered
  • Minor personality changes
  • Emotional response unpredictable and exaggerated
  • “Sundown Syndrome” of late afternoon or early evening may include agitation, confusion, or restlessness can occur at this stage or in the next (moderate) stage

Moderate –

  • Memory impairment is obvious
  • Short-term memory vanishes and stories and actions are likely to be repeated over and over again
  • Individual needs supervision as complex tasks become overwhelming and decision-making is impaired
  • Sleep cycles are disrupted
  • Poor coordination, agitation, wandering and pacing may emerge Contact local Alzheimer’s Associations about their Safe Return Program
  • Behavior problems are more frequent with exaggerated moods, hostility and aggression

Severe –

  • Person needs help in basic activities of daily living, such as bathing, eating and toileting
  • Fragments of memory remain
  • Troublesome behaviors are less prevalent
  • Individuals suffer acute confusion, hallucination, delusions, paranoia, physical rigidity and/or seizures

Resources for Caregivers

  • Call 2-1-1 throughout Texas for information and access to health and human service information for all ages.
  • Call 800-252-9240 to find local Texas Area Agency on Aging.
  • Call 800-677-1116 – Elder Care Locator service to find help throughout the U.S.

Use resources such as Area Agency on Aging (AAA). Types of assistance provided by AAAs:

  • Information and referral
  • Caregiver education and training
  • Caregiver respite
  • Caregiver support coordination
  • Case management
  • Transportation assistance

Assistance available through AAAs for persons age 60 and older may include:

  • Benefits counseling
  • Ombudsman – advocacy for those who live in nursing homes and assisted living facilities
  • Home-delivered meals
  • Congregate meals
  • Light housekeeping

Be sure to check out our Resource Directory, FAQ, and Educational Events Calendar for more great information! Permission is granted to duplicate any and all parts of this page to use in education programs supporting family members caring for elders.

Sources: Alzheimer’s Association  Types of Dementia, Alzheimer’s Association Dementia Related Conditions, Centers for Disease Control and Prevention

Revised March 2022
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We hope this information is helpful to you in the important work you do as a family caregiver.
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