The stages of Alzheimer’s

Alzheimer’s disease is a chronic condition that progresses slowly but inexorably. Find out what are the phases that diagnosed patients go through.

Last update: December 30, 2021

Alzheimer’s disease is a brain disorder characterized by the progressive degeneration of many cognitive functions. According to the World Health Organization (WHO), up to 70% of dementia cases correspond to the condition. Seven stages of Alzheimer’s are distinguished, which determine the condition of the diagnosed patients.

According to the Centers for Disease Control and Prevention (CDC), the disease represents the sixth leading cause of death among American adults. Three types are often listed: mild, moderate, and severe. However, the 7-phase distinction of Alzheimer’s is preferred as these are better suited to the clinical characteristics of the patients.

7 phases of Alzheimer’s

As the National Institute on Aging (NIA) reminds us, most symptoms of the disease appear around the age of 60. However, the changes that anticipate the condition can occur up to a decade earlier, such as the abnormal accumulation of proteins that then evolves to amyloid plaques. Let’s see what the stages of Alzheimer’s are.

1. Preclinical phase

Neurological changes begin long before symptoms are apparent, making it difficult to diagnose Alzheimer’s disease early.

Changes in the brain can be anticipated up to a decade before symptoms appear. According to John Hopkins Medicine, this stage is called preclinical Alzheimer’s disease, so that the patient cannot objectively be aware of these changes.



Researchers see this stage as a substantial opportunity to anticipate the degenerative damage that will occur in the coming years. Experts diagnose this phase when a abnormal deposit of substances known as amyloid Y tau.

2. Basic forgetting phase

Having memory lapses is considered normal. People of all ages suffer from it, although it increases as we age. One of the phases of Alzheimer’s in which the first symptoms begin to appear is when people forget some words, objects, references and so on.



Studies warn that cognitive deficits can go unnoticed, either because they are confused with episodes of forgetfulness due to age or because they are simply not given importance. These changes do not affect the way of relating to others or having a normative life, since they are very specific or basic.

3. Mild decline phase

Most Alzheimer’s diagnoses are made at this stage, since it is when symptoms that are difficult to associate with age begin to appear. The patient no longer forgets only the name of an object or a word in isolation, but may present the following:

  • Having trouble remembering what you read just now.
  • Inability to remember orders or commands.
  • Problems making a plan and carrying out a systematic or organizational task.
  • There are challenges to adapt to social environments.
  • Continuously asking questions that were clarified a moment ago.

Symptoms such as stress or anxiety often also develop, as the patient is aware to some extent of these forgetfulness. Here family and friends begin to be affected by the condition.

4. Moderate decline phase

It is an extension of the previous phase, only this time the episodes are more frequent and intense. Other aspects of cognition are also beginning to be affected, such as the ability to do calculations or to express language. Let’s see some characteristics of this stage:

  • Problems remembering dates, writing them or calculating them in the future.
  • Trouble remembering what day it is, what year or what month.
  • Difficulty remembering things about themselves.
  • Problems cooking or following a recipe.
  • Difficulty carrying out daily tasks that require systematic steps (cleaning, for example).

This is one of the phases of Alzheimer’s in which symptoms begin to affect patients in a holistic way. For example, they may have trouble choosing clothing items based on the weather, changes in sleep patterns, and situations where they get lost or misplaced when unaccompanied.

5. Severe moderate decline phase

It is at this point in the Alzheimer’s phases that patients begin to lose their independence. In the previous stages with minor or major setbacks, people could defend themselves, but here they require permanent vigilance from their relatives or a caregiver. Those affected suffer from the following:

  • They have trouble remembering their home address, phone number, and the names of those outside of their inner circle.
  • They forget the details of things that they just did or that they did in previous days very frequently.
  • They have a hard time learning new things.
  • They suffer from problems doing daily tasks independently.
  • They have emotional changes that can cause them to develop paranoia, delusions and even hallucinations.

The latter is very common, so the circle must be prepared to deal with these episodes. The memory loss is not total, since can recall precise details of their past or of some events in the present.

6. Severe decline phase

Gradually, Alzheimer’s patients tend to find it difficult to fend for themselves.

In this phase the patient can recognize faces, but often forgets names (even those of his inner circle). They also begin to confuse people or suffer from severe delusions. For example, they may mistake a sibling for their father or have the need to go to work even when they have been retired for years. Let’s look at other examples:

  • They may require help to go to the bathroom.
  • They can manifest complications to feed themselves (as a consequence they can lose weight).
  • They usually require the help of others to dress.
  • Changes in sleep patterns are exacerbated.
  • Frustration due to dependency when doing basic tasks.
  • Impaired ability to communicate.

Emotional changes get worse, to the point that they can show up every day. Some patients can communicate basic ideas, but complex ideas are restricted almost by complex. For example, verbally expressing emotions or feelings is challenging.

7. Very severe decline phase

The last of the stages of Alzheimer’s is severe decline. It is a point of no return in which the brain cells have been destroyed so much that the disconnection with reality is total. The patient slowly shuts down until his ability to communicate is nil, also to develop movements or physical activities.

This is why they require attention 24 hours a day. The body becomes more susceptible to infection, so many people get pneumonia. Patients lose the ability to discern when they are hungry or thirsty, which implies full attention in this regard.

As you can see, the stages of Alzheimer’s appear progressively and always require the mediation of family members or healthcare professionals as a complement. The change from one phase to another can take months or years, as progress depends on many factors.

It might interest you …