What Are the 7 Main Stages of Alzheimer's Disease?

Alzheimer’s disease is a form of dementia that impacts a person’s memory, thinking and behavior. Over time, symptoms of the disease grow severe enough to interfere with daily life. More than 5 million Americans are living with Alzheimer’s today. By 2050, this number is expected to rise to almost 14 million.

As people progress through the stages of Alzheimer’s disease, they become less capable of taking care of themselves. As a result, loved ones or paid caretakers have to take on the responsibility. In the United States, more than 16 million Americans provide unpaid care for people with Alzheimer’s or other types of dementia.

How quickly Alzheimer’s disease progresses varies for each person, but it can range from 4 to 20 years. On average, most individuals live for 4-8 years after their diagnosis. Alzheimer’s disease is challenging both for the individual and their loved ones. Having an understanding of what’s to come can help everyone prepare themselves as much as possible. There are seven recognized stages of Alzheimer’s disease that clearly illustrate how a person progresses through the condition.

Stage 1: No Impairment

When someone is in stage one, they have normal outward behavior and no symptoms that you can spot. No memory problems are happening. At this stage, the only thing that triggers an Alzheimer’s disease diagnosis is a PET scan — an imaging test that shows how the brain is working.

Stage 2: Very Mild Cognitive Decline

In stage two, the individual starts to experience some very mild forgetfulness that’s common with the person’s age demographic. Incidents of memory loss or confusion are common in almost half the population of adults aged 65 and older. Loved ones may start to notice these small changes, but it’s often such a mild decline that a doctor won’t identify it as Alzheimer’s symptoms. The symptoms at this stage are dismissed as the normal cognitive decline that comes with aging.

At this stage, the person may start to notice that they:

• Can’t recall names as well as they could 5-10 years ago
• Can’t remember where they placed things earlier
• Have trouble concentrating
• Have difficulty finding the correct word when speaking
• Are unable to master new skills at work or at home

In stage two, the symptoms are not severe enough to impact an individual’s ability to work or live independently. If a person were to take a memory test at this stage, they would still perform well.

Stage 3: Mild Cognitive Decline

In stage three, individuals start to experience increased forgetfulness, difficulty with focus and trouble concentrating. The disease symptoms are beginning to advance to the point that they may result in decreased work performance. Those who aren’t working may experience decreased performance with ordinary household tasks, such as paying bills and cleaning.

Some of the symptoms a person may exhibit in stage three are:

• Getting lost sometimes
• Struggling with finding the right words when communicating
• Forgetting something they just read
• Asking the same question repeatedly
• Finding it challenging to make plans or organize
• Inability to remember names when meeting new people
• Losing items frequently, including valuables

By this stage, the symptoms are significant enough that the person’s family members notice them. Loved ones may choose to step in to assist at this point. This can include making appointments for a loved one, paying their bills or suggesting they start considering retirement.

In stage three, performance on a memory test would be affected, and a physician may detect impaired cognitive function.

The average duration of stage three is approximately 7 years before the onset of dementia.

Stage 4: Moderate Cognitive Decline

In the first three stages of Alzheimer’s disease, the individual isn’t considered to have dementia yet. However, by stage four, the individual is categorized as having early-stage dementia.

At this stage, all previous symptoms become more severe. The individual experiences increased forgetfulness even with recent events, has difficulty with concentration and problem-solving. Complex tasks, organizing and expressing thoughts all become challenging. However, the person can usually still remember some things, such as their home address.

A person experiencing the symptoms of stage four may:

• Struggle with putting the right date or amount on a check when paying bills
• Forget the current month or season
• Struggle with traveling to unfamiliar areas alone
• Have difficulty cooking or even ordering off of a menu
• Have trouble with simple arithmetic
• Develop issues with short-term memory, such as difficulty remembering what they had for their last meal
• Forget details about their life history

Often in stage four, the individual may be in denial about their symptoms. They may unconsciously start to withdraw from conversations and avoid tasks they find challenging so they can stay in denial longer, and as socialization becomes more difficult, the person may even begin to intentionally withdraw from friends and family. “Emotional flattening,” where the person seems uninterested and emotionally unavailable, may begin at this point.

At this stage, a medical professional could quickly identify a cognitive decline during an interview with the person. A diagnosis of Alzheimer’s disease can be made with considerable accuracy at this stage.

Loved ones are encouraged to start to take more control by stage four by encouraging the individual to stop driving, taking control of their finances, and making frequent check-ins. The individual may be able to still live independently at home or in a community-like setting, but loved ones should make regular visits and provide frequent assistance.

The average duration of stage four is approximately 2 years.

Stage 5: Moderately Severe Cognitive Decline

Stage five marks the beginning of moderate dementia. Memory deficiencies are now becoming severe, and people often require assistance with daily living activities. An individual may start to need help with dressing and preparing meals. Some loved ones may choose to limit their assistance so that the individual still feels some degree of independence. For example, a loved one may lay out the individual’s clothes for the day, but allow them to dress independently.

If the individual was previously living independently at home, this would have to change. At this stage, the person requires monitoring and can no longer live alone. If a person in stage five doesn’t get the support they need from loved ones or hired help, they often develop behavioral problems such as anger and suspiciousness.

Some of the common symptoms in stage five are:

• Forgetting important information, such as a home address and phone number
• Difficulty identifying where they are or what time of day it is
• Forgetting significant life details, such as where they went to school
• Inability to remember significant current-day information, such as the name of the President
• Confusion about picking appropriate types of clothing for the season
• Repeating the same question
• Difficulty with simple arithmetic, such as counting down from 20 by twos
• Wearing the same clothes every day unless they’re reminded to change

While individuals require some assistance and frequent monitoring in stage five, they still retain some functionality. They may be able to go to the bathroom and shower or bathe independently.

Often in stage five, the person may remember specific details — like their home address — one day and then forget it the next. The individual may have difficulty remembering sometimes, but they can still tell stories and have some conversations. Encourage them to use their imagination and ask them to tell stories.

Stage five typically lasts 1.5 years.

Stage 6: Severe Cognitive Decline

Stage six is also sometimes referred to as “middle dementia.” At this stage, an individual needs substantial assistance to carry out simple day-to-day activities, and completing tasks becomes much more difficult.

Additionally, stage six is the start of significant personality changes. The person may start to suffer from anxiety, agitation and delusions. For example, they may think they have to get ready for work, even if they haven’t held a job for several years.

Some of the common symptoms in stage six are:

• Difficulty remembering recent events
• Remembering faces but forgetting the names of close family members and friends
• Confusing individuals, such as thinking their wife is their mother
• Retaining little memory of their earlier lives
• Difficulty with cognitive skills, such as counting backward from 10
• Incontinence of the bowel or bladder
• Diminished speaking ability
• Problems putting on clothes properly
• Requiring help with bathing and maintaining personal hygiene
• Tendency to wander if left unsupervised

On average, stage six lasts 2.5 years.

Stage 7: Very Severe Cognitive Decline

The seventh and final stage of Alzheimer’s is known as late-stage dementia. At this stage, the individual has lost their ability to speak or communicate. They require assistance with almost all daily activities, including bathing, dressing, toileting and eating. The individual also needs around-the-clock supervision. They often have to be given soft food that’s easy to swallow and be reminded to drink water.

People in stage seven often lose their psychomotor capabilities and may be unable to walk or require significant assistance to do so.

This stage lasts an average of 2.5 years.