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Alzheimer's disease stages

​Alzheimer's disease is a brain disorder that progress through different stages as it becomes more severe.

There is no cure for the disease, but symptoms can be treated and, in some cases, the progress of the disorder slowed.

The Neurosciences team of Marshfield Clinic treats all diseases and conditions of the brain, spinal chord and the networks of sensory nerve cells called neurons.

What Are the Stages of Alzheimer Disease?

Alzheimer disease is a brain disorder that causes memory loss, confusion, and changes in personality.

It is a type of dementia. At first, people with this disease have only a small amount of memory loss and confusion. This is called “cognitive decline.” Over time, however, these symptoms get more severe.

The disease progresses through 3 main stages of symptoms. In the final stage, people with Alzheimer disease may be unable to talk with family members or know what is going on around them.

This disease cannot be cured. Healthcare providers and caregivers often focus treatment on slowing the process and ensuring a good quality of life for everyone involved.

Facts about Alzheimer disease

Alzheimer disease is becoming more common as the general population gets older and lives longer. Alzheimer disease usually affects people older than 65. A small number of people have “early-onset” Alzheimer disease, which starts when they are in their 30s or 40s.

People live for an average of 8 years after their symptoms appear. But the disease can progress quickly in some people and slowly in others. Some people live as long as 20 years with the disease.

No one knows what causes Alzheimer disease. Genes, environment, lifestyle, and overall health may all play a role.

Stages of Alzheimer disease

The stages of Alzheimer disease usually follow a progressive pattern, but each person moves through the disease stages in his or her own way. Knowing these stages helps healthcare providers and family members make decisions about how to care for someone who has Alzheimer disease.

Preclinical stage. Changes in the brain begin years before a person shows any signs of the disease. This time period is called  preclinical Alzheimer disease and it can last for years.  

Mild, early stage. Symptoms at this stage include mild forgetfulness. This may seem like the mild forgetfulness that often comes with aging but may also include problems with concentration. 

A person may still live independently but may have problems:

  • Remembering a name

  • Recalling recent events

  • Remembering where he or she put a valuable object

  • Making plans

  • Staying organized

  • Managing money

The person may be aware of memory lapses and their friends, family or neighbors may also notice these difficulties. 

Moderate, middle stage. This is typically the longest stage, usually lasting many years.  At this stage, symptoms include:

  • Increasing difficulty remembering events

  • Problems learning new things

  • Difficulty with planning complicated events, like a dinner

  • Trouble remembering his or her name, but not details about his or her own life, like address and phone number

  • Problems with reading, writing, and working with numbers

As the disease progresses, the person may:

  • Know that some people are familiar, but not remember their names, or forget the names of a spouse or child

  • Lose track of time and place

  • Need help choosing the right clothing, getting dressed, and daily activities, like brushing teeth

  • Become moody or withdrawn, or have personality changes, like hallucinations, paranoia, or delusions  

  • Be restless, agitated, anxious, or tearful, especially in the late afternoon or at night

Physical changes may occur as well. Some people have sleep problems.  Wandering away from home is often a concern. 

Severe, late stage. At this stage, a person:

  • Loses many of his or her physical abilities, including walking, sitting, eating.

  • May lose bowel and bladder control

  • May be able to say some words or phrases, but not carry on a conversation.

  • Needs help with all activities all of the time. 

  • Is unaware of recent experiences and of his or her surroundings

  • Is more likely to get infections, especially pneumonia


The early signs of Alzheimer disease may not be obvious to anyone except the person with the disease and the people closest to him or her. Even then, the symptoms may be confused with normal changes that come with age.

To make a diagnosis, healthcare providers usually do an interview with you that uses several types of tests to find out how well your brain is working. These are often memory tests. They may seem like puzzles or word games.

Your healthcare provider might also take a medical history and order some tests to check for other possible causes of memory loss or confusion.

These tests may include brain scans, such as computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET). He or she might talk to your family members about symptoms they have noticed.


Treatment varies based on your age, overall health, medical history, symptoms, and preferences. Some medicines can slow the progress of the disease in some people. These may work for a few months to a few years.

Treatment might also be needed to help you with feelings of depression or anxiety. Sleep disorders can also be treated.

Caregivers and family members may benefit from therapy and support groups.


Experts don’t know how to prevent Alzheimer disease. Most experts recommend a healthy, active lifestyle as the best way to protect your brain’s health.

Managing Alzheimer disease

People with Alzheimer disease need to follow a comprehensive treatment plan to protect their health. Even though you may have this disease, it is still important to take care of your physical health.

Finding help

You and your family may have many questions about living with Alzheimer disease. You can find information and support for yourself and your caregivers through the Alzheimer’s Association.

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What Do You Know About Alzheimer's Disease?

Find out more about this degenerative disease of the brain by taking this quiz.

1. Alzheimer's is the most common form of which of these?
2. How is Alzheimer's diagnosed?
3. Physiologically, what happens to the brain as Alzheimer's progresses?
4. Which of these is the strongest risk factor for developing the disease?
5. Occasionally, other medical conditions may mimic this disease. What are they?
6. Signs of Alzheimer's include which of these symptoms?
7. Which age group has the highest rate of Alzheimer's cases reported?
8. Because no drugs cure this condition, emphasis is put on delaying the onset of severe symptoms. Which of these strategies helps?
9. The average time from the onset of symptoms to death is how long?
10. If you care for a relative with Alzheimer's, which of these measures will help stabilize the patient mentally?