What Are the 7 Stages of Dementia?

The Global Deterioration Scale for Assessment of Primary Degenerative Dementia, or GDS, defines the 7 stages of dementia. The 7 stages are based on a person's cognitive decline or loss of thinking skills.

Dementia is an umbrella term for memory loss, language difficulties, and other struggles related to problem-solving and thinking abilities that affect the ability to live a normal life. The most common cause of dementia is Alzheimer's.

Dementia triggers a decline in the brain’s ability to function properly. It also affects feelings, relationships, and behavior.

The scale most often used to diagnose dementia is the Global Deterioration Scale for Assessment of Primary Degenerative Dementia, or GDS. The GDS divides dementia into seven stages based on a person’s cognitive decline or loss of thinking skills. This test is most useful in diagnosing people with Alzheimer’s, because some other types of dementia, like frontotemporal dementia, don’t necessarily involve memory loss.

A person in stages 1 to 3 doesn’t normally show enough symptoms for a dementia diagnosis. When diagnosing dementia, a person is usually in or beyond stage 4. Stage 4 is seen as “early dementia,” while stages 5 and 6 are considered “middle dementia.” Stage 7, the final stage, is considered “late dementia."

The seven dementia stages are:

Stage 1

There are no visible or diagnosable signs of dementia during stage 1. A person functions normally and shows no symptoms of memory loss, behavioral problems, or any other issue linked to the beginnings of dementia.

Stage 2

During this stage, a person begins to show mild cognitive decline. This may include forgetfulness, which is often seen as a normal sign of aging. Symptoms of dementia are not completely obvious to caregivers or doctors.

Stage 3

At this stage, there is noticeable cognitive decline. Signs may include episodes of forgetfulness, decreased performance at work, difficulties with speech, and problems focusing on everyday tasks.

Stage 4

“Early dementia” has only one stage: Stage 4, known as moderate cognitive decline. This stage lasts for about two years, and a doctor will notice cognitive issues. People in stage 4 will show clear signs of forgetfulness, have difficulty concentrating, struggle to manage personal finances, easily lose track of time and place, and be afraid of traveling alone to new locations or trying new things.

Additionally, they may have difficulty in social situations and prefer to withdraw from friends and family. Caregivers and loved ones should make a strong effort to actively interact and engage with the person at this stage. They should make plans to become more involved in the daily care of this person as well.

Stage 5

A person in stage 5, the beginning of “middle dementia,” requires full-time assistance to complete activities of daily living. Signs and symptoms of dementia are easily identifiable at this stage. Short-term memory is mostly gone, and they may forget such things as their address or phone number and even the date and time.

Stage 6

A person in stage 6 may start forgetting the names of close friends and family and have little to no memory of recent events. Communication is severely affected, and delusions, compulsions, anxiety, and agitation may become more pronounced. They may also experience more frequent personality or emotional changes, difficulty speaking, and loss of bladder control.

Stage 7

Stage 7 makes up the “late dementia” category. At this stage, there is very severe cognitive decline. A person in this stage has lost the ability to communicate verbally and requires assistance with most activities, including walking. Caregivers should focus mostly on providing comfort, stability, and quality of life. Around-the-clock care is needed.

Damage to brain cells causes dementia, and this hinders a person’s ability to communicate with others. When brain cells can’t communicate as they usually do, feelings, behavior, and thinking are affected.

The brain consists of different regions, and each is in charge of a different function, such as movement and judgment. When cells in one region are damaged, it can’t perform its responsibilities normally.

Doctors diagnose dementia by reviewing a person’s medical history, through a physical examination and laboratory tests, and by looking at changes in thinking and any differences in a person’s day-to-day behaviors.

Doctors can determine if someone has dementia with a high level of certainty. It's more difficult to pinpoint the exact type of dementia, however, because the symptoms of different dementias can overlap. If a doctor diagnoses dementia but doesn’t know its exact type, they may refer the person to a specialist, such as a neurologist.

The cause of dementia determines what treatment a person receives. In the case of Alzheimer’s disease and most other progressive dementias, there’s no known treatment or cure that slows or stops its progression. However, there are medications that may temporarily improve a person’s symptoms.

Nursing homes and assisted living residences are well-equipped to care for people with dementia, especially those who require around-the-clock care.