What Is Alzheimer's Disease, The Symptoms And Causes?

By Michael Arangua|Updated February 18, 2022
CheckedMedically Reviewed By Erika Schad, LCP, CWLC

Source: flickr.com

Rates of diagnosis for Alzheimer's Disease are increasing as more people live longer than ever before. It is one of several different disorders that older adults may develop, which affect memory and cognitive functioning. Although most people have heard of it, many people do not know the definition of Alzheimer's Disease or what caused it. Additionally, many people want to know the symptoms so that they can watch out for those symptoms. This is the resource for everything you want to know about Alzheimer's Disease, including what it is, what causes, and what symptoms to watch for.

Learn more about the Alzheimer's Disease definition, the symptoms, and causes:

Normal Changes In Aging

Everyone forgets things sometimes. This could be forgetting an appointment you were meant to attend. It could mean misplacing your keys and wallet. Just as everyone forgets things, everyone will experience some decline in memory and cognitive functioning as part of their normal aging. Normal memory loss does not usually prevent a person from living a typical life. However, when memory loss is more severe and starts to get in the way of day-to-day functioning, then it might be a sign of a more serious disorder.

Signs Of General Dementia

In the medical field, the term dementia is used to describe many symptoms. These symptoms can include memory impairment, reductions in reasoning and judgment, difficulty with language, and other changes in thinking skills. When someone has dementia, their symptoms usually start gradually and slowly worsen over time. As the symptoms worsen, they can begin to impair a person's abilities to function. It can eventually affect their functioning both at work and home.

Specific signs of dementia include:

  • Repeatedly asking the same question or making the same statements
  • Forgetting common or frequently used words when speaking
  • Mixing up words for different items
  • Difficulty completing familiar tasks, such that they take longer to complete
  • Putting items in inappropriate places and forgetting where they were left
  • Frequently getting lost, even in familiar places
  • Changes in mood and behavior for no clear reason


As noted, these symptoms help to define dementia, as well as define Alzheimer's Disease. However, other conditions can similarly cause these symptoms. Other conditions include Vascular Dementia, Frontotemporal Dementia, and Lewy Body Dementia. Each of these conditions is different from one another and different from Alzheimer's Disease.

Alzheimer's Definition

Alzheimer's Disease is just one form of dementia. In fact, it is the most common form of dementia. As many as 80 percents of dementia cases could be attributed to Alzheimer's Disease. In contrast, to some of the other forms of dementia, Alzheimer's symptoms develop slowly and worsen over time. Although the symptoms do not entirely go away with treatment, treatments are available to slow the progression and help manage the disease.

Age is the great risk factor for developing Alzheimer's Disease. Most cases are diagnosed in people age 65 or older. However, some people under age 65 do start to show early signs of the disease. This is called early-onset Alzheimer's. Currently, it occurs in approximately 200,000 Americans.

Alzheimer's is considered a progressive disease because symptoms show up gradually and appear quite mild at first. The symptoms then worsen slowly over the course of years. Over time, as the symptoms worsen, they increasingly effect the person's ability to function. Eventually, many people with Alzheimer's Disease become unable to care for themselves independently.

Alzheimer's Symptoms

The most associated symptom of Alzheimer's Disease is memory loss. As noted above, that memory loss can appear during conversations and routine daily activities. Memory loss is among the first symptoms of the disease, but Alzheimer's progresses over time with increasing symptoms. It is classified as having three stages with symptoms worsening through the early, the middle, and the later stages. Aside from the memory loss and associated effects, the symptoms include:

  • Difficulty focusing
  • Being confused or disoriented
  • Physical problems with walking and coordination
  • Showing frustration
  • Sudden mood swings
  • Anxiety, depression, and anger
  • Symptoms worsening at night

In the last stages of Alzheimer's Disease, the person will lose most of their abilities. This includes no longer being able to care for themselves. They may forget how to dress. They may forget how to make food. They may even forget that they are hungry and need to consume food.

Alzheimer's symptoms do also appear to contribute to an earlier death. As a result, in the United States, the disorder is considered the sixth leading cause of death. Most with Alzheimer's die within an average of eight years after the symptoms become significantly noticeable. The earlier death rates are due to the changes in functioning, some of which lead to poorer health, especially in the late stage of the disease. Depending on age and general health, the survival ranges from four to twenty years.

Alzheimer's Causes

Scientists and researchers are still unsure about all the factors that can lead to Alzheimer's Disease. It is known that genetics and various environmental factors likely play roles. Considering the genetic factor, someone with a parent who had Alzheimer's is much more likely to develop it too. However, there is no way to predict for certain who will develop the disorder and who will not. A history of head injury also seems to relate to an increased risk of developing Alzheimer's Disease, but it is not clear exactly why.

Alzheimer's Disease causes memory loss and significant declines in cognitive functioning because the tissue of the brain is slowly breaking down. This happens as a result of two types of damage in the brain. One damage that occurs is the development of neurofibrillary tangles. The second type of damage is due to protein deposits, which are called beta-amyloid plaques, that build up in the brain.

Again, researchers are not entirely sure what causes these types of damage. There is some research that suggests a protein in the blood called apolipoprotein E (or ApoE) may be at least partly responsible. That protein is used by the body to help move cholesterol in the blood. There are multiple types of ApoE, and it seems certain forms contribute to brain damage. Perhaps related to the ApoE protein, people who have high cholesterol and high blood pressure are at greater risk of developing Alzheimer's.

Alzheimer's Evaluation And Diagnosis

When someone sees signs and symptoms of Alzheimer's Disorder, it is important to visit a medical professional. Doctors will do a complete medical assessment to help determine the exact diagnosis and plan for treatment. The evaluation will include gathering medical history, testing mental status, assessing mood to rule out other mental disorders, a physical exam, neurological tests, and other tests or scans of the brain and body. As the doctor rules out other conditions, they may diagnose Alzheimer's.

Alzheimer's Treatments

Unfortunately, Alzheimer's Disorder still has no known cure, and there is no way to slow the progression of the disease once it starts. However, research has developed treatments that can slow the progression of the symptoms. This can help to improve and extend the quality of life for people who have Alzheimer's. It can help them maintain independent functioning for longer. When they have caregivers, these treatments can reduce the burden. Research continues to find even better treatments.

In addition to medications used to slow the progression of Alzheimer's symptoms, therapy can also be utilized to help people maintain their functioning. Some individuals with Alzheimer's Disease choose to enter assisted living care. This may become more necessary in the later stages of the disease when family caregivers are no longer fully equipped for the person's increasing medical and physical needs. Assisted living facilities have staff and support in place to provide the person with appropriate care.


Final Recommendations

Normal aging brings with it some changes in memory and cognitive functioning for everyone. However, if you have noticed more severe symptoms that seem to be affecting your ability to function, it is important to seek medical and psychological evaluation. As noted, such symptoms could be due to many different disorders. No matter the specific diagnosis, it is important to determine the cause and start medical treatment as soon as possible. This will lead to the best outcomes.

Suspecting a diagnosis of dementia or Alzheimer's Disease, or receiving confirmation that you have a disorder, can be upsetting. Many older adults seek out therapeutic support. Some people find this helpful for adjusting to even the normal changes that go along with aging. Trained counselors can help seniors to adapt to aging and to maintain their quality of life for as long as possible. Therapists can also support the emotional changes that can occur during later life, such as grief and depression.

If you have concerns that a family member or friend may have dementia or Alzheimer's Disorder. Help them seek medical attention. If you are in a caregiving role, that can also be stressful. Given the challenges of being a caregiver, many also choose to seek out therapy support. Some older adults and their caregivers seek help through online platforms. This saves time as you can conveniently get the support you need from the safety and comfort of your home.

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