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The Seven Stages of Alzheimer’s Disease

Written by 
Molly Burford
Reviewed by 
Emanuel Singleton, NP

Article at a glance

  • Alzheimer’s is a progressive disease that is marked by memory loss, behavioral problems, cognitive decline, and other symptoms that interfere with day-to-day activities, general functioning, and daily living. 

  • Alzheimer’s gradually worsens over time. It occurs in various clinical stages, though every person with Alzheimer’s will progress differently. However, many follow a similar trajectory.

  • Although there is no current cure for Alzheimer’s and it is considered a terminal illness, early detection can help slow disease progression through various treatment tactics. 

Alzheimer’s disease is a progressive brain disease marked by major memory deficiencies. Because it is a progressive disease, this means its symptoms will gradually worsen over the course of the illness. The disease progresses in three main stages: early stage, middle stage, and late stage. Each of these overarching stages can be broken down into seven specific stages, each one with symptoms varying in severity. 

Everyone with Alzheimer’s disease progresses differently. Also, there is some symptom overlap within the stages. However, these stages can still provide a basic framework for understanding this complex, incurable brain disease and give healthcare providers, caretakers, and close family members a better grasp of a loved one’s own, individual disease progression.

This article will discuss the seven stages of Alzheimer’s disease as well as provide resources for those combatting Alzheimer’s or their loved ones.

What Is Alzheimer’s Disease?

Alzheimer’s disease is a brain disorder that slowly causes memory and cognitive function impairments. Alzheimer’s disease is a type of dementia and in fact, it accounts for 60 to 80 percent of dementia cases, making it the most common form of dementia. The disease usually begins in someone’s mid-60s and it’s important to note that increasing age is the biggest risk factor for developing Alzheimer’s.

There is currently no cure for Alzheimer’s disease. However, early detection can help slow progression and there are medications available to help with symptoms. As well, with much research being done on this illness, there are hopes for more solutions to come in the future.

Note: To learn more about current research to end Alzheimer’s disease, visit this resource.

What Causes Alzheimer’s Disease? 

Alzheimer’s cause is not yet fully understood. That said, the disease is theorized to be triggered by the abnormal build-up of proteins around brain cells. One of these proteins is called amyloid, which forms plaques. Another protein deposit involved is called tau. Tau creates tangles in the brain cells. 

While the exact cause of what causes these proteins to build up is not known, researchers know that the process begins years before symptoms occur. 

How Is Alzheimer’s Diagnosed? 

There is no one reliable test for diagnosing Alzheimer’s. That said, medical providers conduct tests to assess memory impairment and other thinking skills, judge functional abilities, and identify behavior changes. They also perform a series of tests to rule out other possible causes of impairment such as MRI scans and CT scans. 

Are There Ways To Prevent Alzheimer’s?

Again, because the exact cause of Alzheimer’s has yet to be discovered, the exact prevention is also unknown. That said, there are a number of ways to lower the risk of developing Alzheimer’s including: 

What Are The 7 Stages of Alzheimer’s?

Alzheimer’s disease is progressive, which means that symptoms will gradually worsen over time. 

Alzheimer’s occurs in seven different stages. Each of the Alzheimer’s stages will have its own set of signs and symptoms. The early stages of Alzheimer’s are the mildest (mild Alzheimer’s disease), the middle stages are moderate (moderate Alzheimer’s disease) and the final stages are severe (severe Alzheimer’s disease).

Again, it is important to note that every person with Alzheimer’s disease will experience it differently and some stages will have symptom overlap. However, these stages help give a general understanding of this complex brain disease. 

Stage 1: No Cognitive Impairment

Stage one occurs before people exhibit any symptoms, and is often referred to as preclinical Alzheimer’s disease.” Despite the lack of signs, the brain is changing during this period, with an abnormal build-up of proteins around brain cells.

Stage 2: Very Mild Cognitive Decline

Stage two is marked by basic forgetfulness that largely goes unnoticed. During this stage, these memory lapses may be attributed to normal aging. For example, misplacing the car keys or forgetting words. 

During this stage, it’s also unlikely that friends, close family members, and coworkers recognize any issues. Furthermore, it’s unlikely that providers can detect Alzheimer’s during regular primary care visits at this stage.

Stage 3: Mild Cognitive Impairment (Mild Alzheimer’s disease) 

Stage three is when noticeable memory difficulties first occur. Family members, close friends, and coworkers may begin to notice symptoms during this early stage such as increased forgetfulness. 

If medical attention is sought, a healthcare provider will look for concentration and memory issues such as: 

  • Difficulty with tasks in social settings 

  • Trouble thinking of the right word or name

  • Losing and/​or misplacing objects

  • Struggling with planning and organizing

  • Short-term memory lapses (i.e. forgetting information after immediately reading)

Stage 4: Moderate Cognitive Decline

In the fourth stage of Alzheimer’s, increased forgetfulness continues and cognitive skills decline. As well, noticeable symptoms outside of memory problems appear. This includes personality changes. Stage four can last several years. 

Common difficulties and symptoms of this specific stage include:

  • Forgetting recent events

  • Struggling to perform complex tasks

  • Forgetting one’s personal history

  • Personality changes (i.e. withdrawal, moodiness, depression, increased anxiety) 

  • Changes in sleep patterns

Stage 5: Moderately Severe Decline

The fifth stage of Alzheimer’s is marked by decreased independence due to disease progression. Prior to stage five, a person with Alzheimer’s could be under their own care. Now, basic tasks such as preparing meals will need to be performed by someone else.

Other common difficulties and symptoms during this stage include: 

  • Trouble recalling personal details (i.e. address and phone number)

  • Emotional changes (delusions, paranoia, etc.)

  • Cognitive problems (i.e. inability to learn something new)

Stage 6: Severe Decline

The sixth stage of Alzheimer’s disease (occasionally referred to as Moderately severe dementia”) sees worsening memory and significant personality changes. As well, extensive assistance may be necessary at this point and constant supervision may be required. 

Other symptoms include: 

  • Needing help finding proper clothing

  • Trouble remembering their personal history 

  • Disruptions in sleep patterns

  • Difficulty controlling bladder and bowel movements

  • Major behavioral changes, such as wandering and getting lost 

Stage 7: Very Severe Cognitive Decline (Final Stage)

Stage seven is the final stage of Alzheimer’s. By the last of the final stages, people with Alzheimer’s disease will lose their ability to respond to their environment. Carrying on a conversation is no longer possible. Abnormal reflexes and movement, as well as physical impairment, are to be expected.

Someone in the seventh stage will need extensive assistance with their daily care. 

What To Do If Alzheimer’s Disease Is Suspected

If Alzheimer’s disease is suspected, a health care provider should be contacted immediately. Early intervention can help slow disease progression. These interventions may include the use of some medications.

How is Alzheimer’s Disease Treated?

While there is no cure for Alzheimer’s, there are treatments available that can help symptoms. Because Alzheimer’s is complex, usually a variety of medical interventions are necessary such as medications and moving to an assisted living facility. 

Recently, the FDA approved a new medication called aducanumab. This medication reduces amyloid deposits in the brain, which may slow disease progression. Aducanumab is currently the only FDA-approved disease-modifying medication. However, aducanumab has not been clinically proven to affect symptoms or outcomes. That said, clinical studies are continued to be performed regarding this medication.

Medications will be most effective during the middle stage of Alzheimer’s, which is why early detection is so important. However, there are still medications available for the late stages of Alzheimer’s including donepezil.

Note: Learn more about treatments for Alzheimer’s at this resource.

Resources For Family Members and Caregivers

Having a loved one with Alzheimer’s can be difficult. There are a number of resources for friends, family members, and caregivers that can help. These include: 

Note: To learn more about getting help as a caregiver, visit this resource.


How long do the seven stages of Alzheimer's last?

While each stage may vary in length, on average, it can take as long as 25 years to move through all seven stages. It's possible, given the mild symptoms of earlier stages, that the duration could be longer since the disease existed before the person was aware.

What is the average lifespan of someone with Alzheimer's disease?

Timelines may vary, but those with Alzheimer's may live on average between 3-11 years after diagnosis. Some patients may live decades longer.

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