Alzheimer's disease typically progresses slowly in three general stages — mild (early stage), moderate (middle stage), and severe (late stage). Since Alzheimer's affects people in different ways, the timing and severity of dementia symptoms varies as each person progresses through the stages of Alzheimer's differently.
Overview of disease progression
The symptoms of Alzheimer's disease worsen over time, although the rate at which the disease progresses varies. On average, a person with Alzheimer's lives four to eight years after diagnosis, but can live as long as 20 years, depending on other factors. Changes in the brain related to Alzheimer's begin years before any signs of the disease. This time period, which can last for years, is referred to as preclinical Alzheimer's disease.
The stages below provide an overall idea of how abilities change once symptoms appear and should only be used as a general guide. (Dementia is a general term to describe the symptoms of mental decline that accompany Alzheimer’s and other brain diseases.)
The stages are separated into three categories: mild Alzheimer's disease, moderate Alzheimer's disease and severe Alzheimer's disease. Be aware that it may be difficult to place a person with Alzheimer's in a specific stage as stages may overlap.
Early-stage Alzheimer's (mild)
In the early stage of Alzheimer's, a person may function independently. He or she may still drive, work and be part of social activities. Despite this, the person may feel as if he or she is having memory lapses, such as forgetting familiar words or the location of everyday objects.
Symptoms may not be widely apparent at this stage, but family and close friends may take notice and a doctor would be able to identify symptoms using certain diagnostic tools.
Common difficulties include:
- Coming up with the right word or name.
- Remembering names when introduced to new people.
- Having difficulty performing tasks in social or work settings.
- Forgetting material that was just read.
- Losing or misplacing a valuable object.
- Experiencing increased trouble with planning or organizing.
During the early stage, it’s possible for people with dementia to live well by taking control of their health and wellness, and focusing their energy on aspects of their life that are most meaningful to them. In addition, this is the ideal time to put legal, financial and end-of-life plans in place because the person with dementia will be able to participate in decision-making.
Middle-stage Alzheimer's (moderate)
Middle-stage Alzheimer's is typically the longest stage and can last for many years. As the disease progresses, the person with Alzheimer's will require a greater level of care.
During the middle stage of Alzheimer’s, the dementia symptoms are more pronounced. The person may confuse words, get frustrated or angry, and act in unexpected ways, such as refusing to bathe. Damage to nerve cells in the brain can also make it difficult for the person to express thoughts and perform routine tasks without assistance.
Symptoms, which vary from person to person, may include:
- Being forgetful of events or personal history.
- Feeling moody or withdrawn, especially in socially or mentally challenging situations.
- Being unable to recall information about themselves like their address or telephone number, and the high school or college they attended.
- Experiencing confusion about where they are or what day it is.
- Requiring help choosing proper clothing for the season or the occasion.
- Having trouble controlling their bladder and bowels.
- Experiencing changes in sleep patterns, such as sleeping during the day and becoming restless at night.
- Showing an increased tendency to wander and become lost.
- Demonstrating personality and behavioral changes, including suspiciousness and delusions or compulsive, repetitive behavior like hand-wringing or tissue shredding.
Late-stage Alzheimer's (severe)
In the final stage of this disease, dementia symptoms are severe. Individuals lose the ability to respond to their environment, to carry on a conversation and, eventually, to control movement. They may still say words or phrases, but communicating pain becomes difficult. As memory and cognitive skills continue to worsen, significant personality changes may take place and individuals need extensive care.
At this stage, individuals may:
- Requie round-the-clock assistance with daily activities and personal care.
- Lose awareness of recent experiences as well as of their surroundings.
- Experience changes in physical abilities, including the walking, sitting and, eventually, swalloing.
- Have difficulty communicating.
- Become vulnerable to infections, especially pneumonia.
The person living with Alzheimer’s may not be able to initiate engagement as much during the late stage, but he or she can still benefit from interaction in ways that are appropriate, like listening to relaxing music or receiving reassurance through gentle touch. During this stage, caregivers may want to use support services, such as hospice care, which focus on providing comfort and dignity at the end of life. Hospice can be of great benefit to people in the final stages of Alzheimer’s and other dementias and their families.
Learn more: Late-Stage Care
The Alzheimer's Association is the leading voluntary health organization in Alzheimer's care, support and research. Our mission is to eliminate Alzheimer's disease through the advancement of research; to provide and enhance care and support for all affected; and to reduce the risk of dementia through the promotion of brain health.