Stages of Alzheimer's Disease: 7 Stage Model

Global Deterioration Scale for Assessment of Primary Degenerative Dementia

1) No Cognitive Decline

2) Very Mild Cognitive Decline (Forgetfulness)

Subjective complaints of memory deficit, most frequently in the following areas:
- Forgetting where one has placed familiar objects
- Forgetting names one formerly knew well.
No objective evidence of memory deficit on clinical interview.
No objective deficits in employment or social situations.
Appropriate concern with respect to symptomatology.

3) Mild Cognitive Decline (Early Confusional)

4) Moderate Cognitive Decline (Late Confusional)

Clear-cut deficit on careful clinical interview. Deficit is manifest in the following areas:
- Decreased knowledge of current and recent events
- May exhibit some deficit in memory of one's personal history
- Concentration deficit elicited on serial subtractions
- Decreased ability to travel, handle finances, etc.
Frequently no deficit in following areas:
- Orientation to time and person
- Recognition of familiar persons and faces
- Ability to travel to familiar locations
- Inability to perform complex tasks.
Denial is the dominant defense mechanism.
Flattening of affect and withdrawal from challenging situations occur.

5) Moderately Severe Cognitive Decline (Early Dementia)

Patient can no longer survive without some assistance.
Patient is unable, during interview, to recall a major relevant event of their current lives, e.g., an address or telephone number of many years, the names of the high school and/or college from which they graduated, or the names of close family members such as grandchildren.
Frequently some disorientation to time (day of the week, season, etc.) or place.
An educated person may have difficulty counting back from 40 by fours or from 20 by twos.
A patient at this stage retains knowledge of many facts regarding themself and others. They invariably know their own name and generally know their spouse's and children's names.
They require no assistance with toileting and eating, but may have some difficulty choosing the proper clothing to wear.

6) Severe Cognitive Decline (Middle Dementia)

May occasionally forget the name of the spouse upon whom they are entirely dependent for survival.
Will be largely unaware of all recent events and experiences in their lives. May retain some knowledge of their past lives, but this is sketchy.
Generally unaware of their surroundings: the year, the season, etc.
May have difficulty counting from 10 both backwards and, sometimes, forward.
Will require some assistance with activities of daily living, e.g., may become incontinent, will require travel assistance but occasionally will display ability to recognize familiar locations.
Diurnal rhythm frequently disturbed.
Almost always recalls their own name.
Frequently continue to be able to distinguish familiar from unfamiliar persons in their environment.
Personality and emotional changes occur. These are widely variable and include:
- Interaction with nonexistant figures in the environment, or may talk to their own reflection in the mirror
- Obsessive symptoms, e.g., person may continually repeat simple cleaning activities
- Anxiety symptoms, agitation, and even previously nonexistent violent behavior may occur
- Cognitive abulla i.e., loss of will power because an individual cannot carry through long enough to determine a purposeful course of activity.

7) Very Severe Cognitive Decline (Late Dementia)

All verbal abilities are lost. Frequently there is no speech at all - only grunting.
Incontinent, requires assistance toileting and feeding.
Lose basic psychomotor skills, e.g. ability to walk. The brain appears to be no longer able to tell the body what to do.
Generalized and cortical neurological signs and symptoms are frequently present.