Alzheimer’s disease is a progressive disease, developing slowly and gradually worsening, typically over a period of several years. It impacts memory, thinking, language, problem-solving, and even personality and movement as the disease progresses. While not everyone will experience the same symptoms, and the disease may progress at a different rate for each individual, there is a similar trajectory that most people follow as the disease progresses. The typical progression of Alzheimer’s disease may be broken down into three, five, or seven stages. 

Prior to Diagnosis: No Dementia

In the first three stages of the seven-stage model, an individual is not considered to have dementia, as the symptoms are commonly associated with typical aging and are not typically noticeable by healthcare providers or family members. This is also known as Pre-clinical Alzheimer’s Disease.

Stage One: No Impairment

In the first stage, a person with Alzheimer’s disease has no memory impairment with no evident symptoms of dementia. At this stage, Alzheimer’s disease is undetectable. This stage is also sometimes called No Cognitive Decline.

Stage Two: Very Mild Cognitive Decline

In this stage, a person with Alzheimer’s disease begins to experience the typical forgetfulness associated with aging. They may forget where they left their car keys or their purse. These symptoms are typically not noticed by the individual’s family members or physician.

Stage Three: Mild Cognitive Decline

Individuals in this stage experience increased forgetfulness as well as slight difficulty with focus or concentration. These symptoms may result in decreased work performance for those in the workforce, or for those who do not hold outside employment, they may experience decreased performance in ordinary household tasks such as cleaning or paying bills. They may get lost or begin to struggle to find the right words in communication.

In stage three, increased forgetfulness and decreased performance are likely to be noticed by the person’s family members. The average duration of stage three is approximately seven years prior to the onset of dementia.

Early-Stage Dementia

In the first three stages above, an individual is not considered to have dementia. At stage four, however, that changes, and a person is considered to have early-stage dementia. Note that early-stage dementia differs from early-onset dementia or early-onset Alzheimer’s disease, which refers to the onset of clinical symptoms prior to age 65.

Stage Four: Moderate Cognitive Decline

Stage four comprises what is clinically described as early-stage dementia. A person with early-stage dementia (in stage four of the seven-stage model) will experience increased forgetfulness, often forgetting recent events, as well as difficulty concentrating, difficulty with problem-solving, and difficulty managing finances. They may have challenges when traveling to unfamiliar areas alone, and they may have difficulty performing complex tasks or organizing and expressing thoughts.

People in stage four may also be in denial about their forgetfulness and other symptoms, and as socialization becomes increasingly difficult, they may begin to withdraw from family and friends. In stage four, a healthcare provider can easily identify cognitive decline in an examination and interview with the patient. The average duration of stage four is approximately two years.

Mid-Stage Dementia

Stage five marks the beginning of mid-stage dementia, which continues through stage six.

Stage Five: Moderately Severe Cognitive Decline

Major memory deficiencies are present beginning in stage five, and people in this stage of the disease may require assistance with activities of daily living, such as bathing, dressing, and preparing meals. Memory deficits in this stage are severe, with individuals often forgetting prominent bits of information that affect their daily lives – such as their home address or phone number. They may not be able to identify where they are (orientation to place) or what time of day it is (orientation to time). Stage five lasts, on average, one and a half years.

Stage Six: Severe Cognitive Decline

Also known as Middle Dementia, stage six marks a period in which a person requires substantial assistance to carry out day-to-day activities. They may have little memory of recent events and forget the names of close friends or family members. Many people in stage six have limited memory of their earlier lives and will also have difficulty completing tasks or successfully exhibiting cognitive skills such as counting backwards from 10.

People in stage six may also begin to experience incontinence of bowel or bladder, and speech ability is often diminished. Significant personality changes may also be noticeable at this stage, as individuals may suffer from delusions, anxiety, or agitation. This stage lasts an average of about two and a half years.

Late-Stage Dementia

The seventh and final stage comprises the final stage in the three-stage model: late-stage dementia.

Stage Seven: Very Severe Cognitive Decline

Also known as Late Dementia, stage seven is the final stage in the progression of Alzheimer’s disease. At this stage, most people will have lost their ability to speak or communicate. They often require assistance with most of their activities, including toileting, eating, dressing, bathing, and other daily activities, around the clock. Because people in stage seven often lose psychomotor capabilities, they may be unable to walk or require significant assistance with ambulation. This stage lasts an average of two and a half years.

Alzheimer’s disease is a progressive disease that gradually worsens over a period of four to 20 years. On average, however, most people live between four and eight years following diagnosis. The progression of the disease may be different for each individual, but family members and caregivers should familiarize themselves with the typical stages that occur throughout progression. It’s a challenging road to travel for both the person with Alzheimer’s disease and those who love them, but knowing what to expect can help to ease some stress and uncertainty.

How Do You Know What Stage of Alzheimer’s Disease a Loved One Is In?

The stages of Alzheimer’s disease presented in this post offer a reasonable framework from which to observe symptoms and understand the progression of the disease. Since there is no medical consensus for Alzheimer’s stages, as there is with cancer, it is important for caregivers to be aware of the individual symptoms and situation that their patient or loved one is experiencing. While healthcare providers may refer to a patient’s condition as “late” or “early” stage, any specific stage is less important than the context and understanding of what this means for care going forward.

What to Do Next After Learning What Stage of Alzheimer’s Disease Your Loved One Is In

As mentioned, learning about the stage of Alzheimer’s disease that a loved one is experiencing helps provide perspective and context. This knowledge makes it easier to have conversations with doctors about the patient’s condition and how to approach future treatment options. Understanding the later stages of the disease also helps when planning for lifestyle changes, new equipment, and other items that may be needed. One of the other major benefits in understanding the overall progression of Alzheimer’s disease is preparing for future living arrangements, such a memory care community, that could become a preferred option during later stages of the disease. Because the cost of dementia care is high, families should begin planning as soon as possible following a diagnosis.

What Causes Alzheimer’s Disease to Progress So Quickly?

The progression of Alzheimer’s disease varies widely between individuals, with most people living with the condition for between 3 and 11 years after the initial diagnosis. In some cases, people may survive for more than 20 years. When Alzheimer’s is detected early, there are possible treatments that can help to slow the progression of the disease and contribute to a longer life expectancy.  

It is therefore crucial to plan for the future and follow the progression of the disease through each stage. Alzheimer’s disease first begins with physical changes in the brain. This can happen at a gradual pace before any noticeable symptoms appear. In fact, this pre-clinical Alzheimer’s disease stage can begin 10 to 15 years before any symptoms appear.

The exact speed of progression is largely based on the inner workings of the brain, and there is little that can be done to influence or predict it aside from medications that can slow the progression of the disease when it’s diagnosed in the early stages. As caregivers and family members, the most important actions to take are those that improve the quality of life for the person under care. There are several excellent and proven therapies and techniques that can be used to improve communication and help a loved one accomplish more and live their life as fully as possible. With proper preparation and a knowledge of individual stages of Alzheimer’s disease, it is possible to create a roadmap for care that leads to meaningful outcomes for everyone involved.