What Is Alzheimer’s Disease?

Table of ContentsView AllTable of ContentsSymptomsStagesDiagnosisCausesTypesTreatmentCoping

Table of ContentsView All

View All

Table of Contents

Symptoms

Stages

Diagnosis

Causes

Types

Treatment

Coping

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Alzheimer’s disease is a progressive and irreversible brain condition. The two most common symptoms of the condition are confusion and memory loss. Alzheimer’s disease slowly causes thinking and memory to deteriorate to the point that even simple tasks become difficult or impossible.

Alzheimer’s disease can eventually cause a person to lose their ability to respond to their environment, including becoming unable to carry out a conversation.

According to the Centers for Disease Control and Prevention (CDC), Alzheimer’s disease is the sixth leading cause of death for adults over the age of 65.

While there isno cure for Alzheimer’s, there are treatments available that can help slow the disease’s progression, making early detection important. Behavioral and medication treatments can also help people cope with the symptoms of the disease.

Causes and Risk Factors of Alzheimer’s Disease

The most common symptom that people begin to notice is difficulty remembering new information. This symptom may be subtle initially, and people may dismiss it as normal forgetting or normal age-related memory decline.

Because of the progressive nature of Alzheimer’s disease, this forgetting will eventually become more pronounced. People may also begin to exhibit more severe memory problems as well as other symptoms, including:

While symptoms can vary from person to person, the progression of the disease usually follows a pattern that can be broken down into three general stages.

Early Stage

During this early stage of the disease, people begin to experience mild symptoms but often still function and live independently. While they continue to live their lives, including doing things like socializing and working, they may have memory lapses that make it difficult to remember words, names, and the locations of everyday things.

Some symptoms that a person might experience at this point include:

Middle Stage

This stage of the disease is usually the longest. During this time, symptoms grow progressively worse, and memories, includinglong-term memories, begin to decline.

Behavioral and emotional changes are also common. People may experience frustration, anxiety, and agitation. It becomes increasingly difficult for people to function, and they depend on others to help with daily tasks.

People at the moderate stage of Alzheimer’s disease display symptoms such as:

Late Stage

During the late stages of the disease, mental function declines to the point that it has a serious impact on physical functioning. At this point, people lose various aspects of motor functioning and the ability to converse. They require around-the-clock care and assistance.

Symptoms at this stage include:

According to the Alzheimer’s Association, a person with Alzheimer’s lives for an average of four to eight years after their diagnosis, but this varies depending on a number of factors and a person may live for 20 years or longer after they are diagnosed.

Symptoms of Alzheimer’s Disease

There is no simple test that can definitively indicate that a person has Alzheimer’s. Doctors will use a number of tests to help diagnose the condition, including neurological tests and brain imaging scans.

Amental status testis used to check yourshort-termand long-term memory. You may be asked to identify what day it is or to memorize and remember a brief list of words.

Your doctor will also take notes on your medical history. They may ask you questions about your past medical conditions and the type of symptoms you are currently experiencing.

A neurological exam may be performed to look at things such as speech, muscle tone, and reflexes. This type of test is used to rule out other conditions, such as stroke or infection.

Other types of tests that may be used to diagnose Alzheimer’s include:

Understanding Primary Progressive Aphasia, The Lesser Known Dementia

Many of these changes in the brain begin to take place at least a decade or more before the first symptoms of the condition begin to appear.

The exact reasons behind these changes in the brain are not entirely known, but it is believed that a combination of age-related, genetic, environmental, and lifestyle factors may play a role in causing Alzheimer’s disease.

Rare Variations in Three Genes Linked with Alzheimer’sAmyloid precursor protein (APP) on chromosome 21Presenilin 1 (PSEN1) on chromosome 14Presenilin 2 (PSEN2) on chromosome 1

Rare Variations in Three Genes Linked with Alzheimer’s

Amyloid precursor protein (APP) on chromosome 21Presenilin 1 (PSEN1) on chromosome 14Presenilin 2 (PSEN2) on chromosome 1

The human braincontains billions of nerve cellsthat communicate with one another to perform a range of functions including thinking and remembering. When proteins build up in the brain, they interfere with the ability of these brain cells to function and progressively cause the death of these cells.

As more cells continue to die, the result is the progressive onset of worsening symptoms that people with Alzheimer’s disease experience.

Risk Factors

Factors that may contribute to the onset of the condition include:

Estimates suggest that around 6.9 million adults are living with Alzheimer’s disease as of 2022.

Causes of Memory Loss

Early-Onset Alzheimer’s

In this type, symptoms may first appear when a person is in their 30s, 40s, or 50s.While the disease is often thought of as something that only happens in old age, it can occasionally affect younger people, although this is much less common.

It is unclear what exactly causesearly-onset Alzheimer’s, but doctors believe it may be due to a rare gene that people inherit.

Late-Onset Alzheimer’s

Inlate-onset Alzheimer’s, which is much more common, symptoms appear at the age of 65 or older.This type of Alzheimer’s is much more common and likely the result of a combination of genetic, environmental, and lifestyle factors.

Conditions That Cause Similar SymptomsIt is also important to note that while Alzheimer’s is one of the most common causes of dementia, there are other conditions that can also result in similar symptoms. Other causes includeNiemann-Pick disease type C (NPC) and Sanfillipo syndrome, dementia with Lewy bodies, frontotemporal dementia, HIV, Huntington’s disease,Parkinson’s disease, and traumatic brain injury.

Conditions That Cause Similar Symptoms

It is also important to note that while Alzheimer’s is one of the most common causes of dementia, there are other conditions that can also result in similar symptoms. Other causes includeNiemann-Pick disease type C (NPC) and Sanfillipo syndrome, dementia with Lewy bodies, frontotemporal dementia, HIV, Huntington’s disease,Parkinson’s disease, and traumatic brain injury.

Organic Mental Disorder Causes and Treatment

There is no cure for Alzheimer’s but there are treatments that may help slow the progression of the disease and make living with the condition more manageable. The treatment that a doctor recommends will depend on the progression of the condition.

Currently, there are medications that may slow clinical decline and treatcognitiveand behavioral symptoms of Alzheimer’s.

Slowing Clinical Decline

In the race for the cure, some drugs, like Aduhelm, received fast-track approval from the FDA based on preliminary outcomes of clinical trials but were quickly removed from the market when they didn’t prove to be as effective as they hoped.There are currently two FDA-approved treatments that target the underlying biological mechanism that causes Alzheimer’s, includinglecanamabLeqembi)anddonanemab(Kisunla). Depending on the stage of Alzheimer’s progression, people taking these new medications experience a significant reduction in cognitive decline and independent functioning.

In the race for the cure, some drugs, like Aduhelm, received fast-track approval from the FDA based on preliminary outcomes of clinical trials but were quickly removed from the market when they didn’t prove to be as effective as they hoped.

There are currently two FDA-approved treatments that target the underlying biological mechanism that causes Alzheimer’s, includinglecanamabLeqembi)anddonanemab(Kisunla). Depending on the stage of Alzheimer’s progression, people taking these new medications experience a significant reduction in cognitive decline and independent functioning.

A doctor must determine if a patient is an eligible candidate for these medications. They first need to determine the presence of amyloid plaques in the brain so that they may conduct a diagnostic test like a cerebral spinal fluid analysis or amyloid PET imaging.

Side Effects

As with any medication, there can be side effects to consider. Side effects of these medications include amyloid-related imaging abnormalities (ARIA). ARIA involves temporary swelling of the brain and may include other symptoms like headache, nausea, vomiting, diarrhea, tremors, vision changes, or gait disturbances. Other side effects include microhemorrhages (a small amount of blood in the brain tissue), superficial siderosis (excess iron in the brain and spinal cord), and altered mental statuses such as confusion, delirium, or disorientation.

Medications in the Works

Improving Cognitive Symptoms

Cholinesterase Inhibitors

Cholinesterase inhibitors work to increase the available amount of aneurotransmitterknown as acetylcholine.Reduced levels ofacetylcholinemay be responsible for some of the symptoms of Alzheimer’s, so increasing levels of this chemical messenger in your brain may help with memory.

These medications don’t stop the decline in cognitive functioning that Alzheimer’s causes, but they may help alleviate the symptoms related to memory, language, thinking, and judgment for a certain amount of time.

The most commonly prescribed medications in this category include:

Side effects may include nausea or vomiting, loss of appetite, and increased frequency of bowel movements

Glutamate Regulators

This class of medications regulates glutamate, a chemical messenger in the brain, which, in excess, can accelerate neuronal death. Taking this medication may improve memory, attention, the ability to reason, language, and the ability to do simple tasks.

Combination Drugs

A doctor might prescribe a combination of a cholinesterase inhibitor and a glutamate regulator to tackle symptoms based on both neurotransmitter irregularities mentioned above.

Improving Behavioral Symptoms

There are many behavioral changes associated with Alzheimer’s, and these symptoms are typically targeted individually depending on what issues are manifesting.

Current medications to treat Alzheimer’s disease focus on slowing the progression and alleviating symptoms of existing conditions. Researchers are still working toward developing future treatments that mayprevent people from developing Alzheimer’s.

How Alzheimer’s Disease Is Treated

An Alzheimer’s diagnosis can be stressful for both the person who has the condition and their loved ones. In addition to drug therapies, there are also lifestyle and behavioral strategies that can help people manage the condition as it progresses.

Expect Challenges

Try not to get frustrated when your loved one forgets or misunderstands something. Focus on being as clear as you can, eliminate distractions, and repeat things if you need to.

Focus on Safety

As Alzheimer’s disease progresses, the individual may face dangers that you did not anticipate. Even normal daily activities can present hazards, so focus on keeping the environment safe based on the individual’s current level of functioning. This might involve removing sharp objects and keeping doors and windows locked to prevent unexpected wandering.

Look for Reasons Behind Behaviors

In some cases, a person may act out with agitation or anxiety if one of their needs is unmet but they are unable to communicate these needs. When such behaviors arise, consider some of the reasons behind them. It might indicate a need for something whether it means going for a walk or having something to eat.

Final Thoughts

Learning more about the disease’s progression, exploring strategies to deal with the different stages of the disease, and finding ways for caregivers to cope are all important.

If you are caring for a loved one with Alzheimer’s, seek support from others such as joining asupport groupor finding healthcare resources in your community that can help.

What Is Dementia?

13 SourcesVerywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Alzheimer’s Association.What is Alzheimer’s disease?Centers for Disease Control and Prevention.About Alzheimer’s.National Institute on Aging.What are the signs of Alzheimer’s disease?Alzheimer’s Disease.Stages of Alzheimer’s.National Institute on Aging.Alzheimer’s disease fact sheet.National Institute on Aging.What causes Alzheimer’s disease?Bendlin BB, Carlsson CM, Gleason CE, et al.Midlife predictors of Alzheimer’s disease.Maturitas. 2010;65(2):131-137. doi:10.1016/j.maturitas.2009.12.014Alzheimer’s Association.Younger/early-onset Alzheimer’s.Rabinovici GD.Late-onset Alzheimer Disease.Continuum (Minneap Minn). 2019;25(1):14-33. doi:10.1212/CON.0000000000000700U.S. Food & Drug Administration.FDA grants accelerated approval for Alzheimer’s drug.Alzheimer’s Association.Medications for memory, cognition, and dementia-related behaviors.U.S. Food and Drug Administration.FDA approves treatment for adults with Alzheimer’s disease.Vejandla B, Savani S, Appalaneni R, Veeravalli RS, Gude SS. Alzheimer’s disease: The past, present, and future of a globally progressive disease.Cureus. Published online January 5, 2024. doi:10.7759%2Fcureus.51705

13 Sources

Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Alzheimer’s Association.What is Alzheimer’s disease?Centers for Disease Control and Prevention.About Alzheimer’s.National Institute on Aging.What are the signs of Alzheimer’s disease?Alzheimer’s Disease.Stages of Alzheimer’s.National Institute on Aging.Alzheimer’s disease fact sheet.National Institute on Aging.What causes Alzheimer’s disease?Bendlin BB, Carlsson CM, Gleason CE, et al.Midlife predictors of Alzheimer’s disease.Maturitas. 2010;65(2):131-137. doi:10.1016/j.maturitas.2009.12.014Alzheimer’s Association.Younger/early-onset Alzheimer’s.Rabinovici GD.Late-onset Alzheimer Disease.Continuum (Minneap Minn). 2019;25(1):14-33. doi:10.1212/CON.0000000000000700U.S. Food & Drug Administration.FDA grants accelerated approval for Alzheimer’s drug.Alzheimer’s Association.Medications for memory, cognition, and dementia-related behaviors.U.S. Food and Drug Administration.FDA approves treatment for adults with Alzheimer’s disease.Vejandla B, Savani S, Appalaneni R, Veeravalli RS, Gude SS. Alzheimer’s disease: The past, present, and future of a globally progressive disease.Cureus. Published online January 5, 2024. doi:10.7759%2Fcureus.51705

Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Alzheimer’s Association.What is Alzheimer’s disease?Centers for Disease Control and Prevention.About Alzheimer’s.National Institute on Aging.What are the signs of Alzheimer’s disease?Alzheimer’s Disease.Stages of Alzheimer’s.National Institute on Aging.Alzheimer’s disease fact sheet.National Institute on Aging.What causes Alzheimer’s disease?Bendlin BB, Carlsson CM, Gleason CE, et al.Midlife predictors of Alzheimer’s disease.Maturitas. 2010;65(2):131-137. doi:10.1016/j.maturitas.2009.12.014Alzheimer’s Association.Younger/early-onset Alzheimer’s.Rabinovici GD.Late-onset Alzheimer Disease.Continuum (Minneap Minn). 2019;25(1):14-33. doi:10.1212/CON.0000000000000700U.S. Food & Drug Administration.FDA grants accelerated approval for Alzheimer’s drug.Alzheimer’s Association.Medications for memory, cognition, and dementia-related behaviors.U.S. Food and Drug Administration.FDA approves treatment for adults with Alzheimer’s disease.Vejandla B, Savani S, Appalaneni R, Veeravalli RS, Gude SS. Alzheimer’s disease: The past, present, and future of a globally progressive disease.Cureus. Published online January 5, 2024. doi:10.7759%2Fcureus.51705

Alzheimer’s Association.What is Alzheimer’s disease?

Centers for Disease Control and Prevention.About Alzheimer’s.

National Institute on Aging.What are the signs of Alzheimer’s disease?

Alzheimer’s Disease.Stages of Alzheimer’s.

National Institute on Aging.Alzheimer’s disease fact sheet.

National Institute on Aging.What causes Alzheimer’s disease?

Bendlin BB, Carlsson CM, Gleason CE, et al.Midlife predictors of Alzheimer’s disease.Maturitas. 2010;65(2):131-137. doi:10.1016/j.maturitas.2009.12.014

Alzheimer’s Association.Younger/early-onset Alzheimer’s.

Rabinovici GD.Late-onset Alzheimer Disease.Continuum (Minneap Minn). 2019;25(1):14-33. doi:10.1212/CON.0000000000000700

U.S. Food & Drug Administration.FDA grants accelerated approval for Alzheimer’s drug.

Alzheimer’s Association.Medications for memory, cognition, and dementia-related behaviors.

U.S. Food and Drug Administration.FDA approves treatment for adults with Alzheimer’s disease.

Vejandla B, Savani S, Appalaneni R, Veeravalli RS, Gude SS. Alzheimer’s disease: The past, present, and future of a globally progressive disease.Cureus. Published online January 5, 2024. doi:10.7759%2Fcureus.51705

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