The Global Deterioration Scale for Assessment of Primary Degenerative Dementia, otherwise known as the Reisberg Scale or simply GDS, divides dementia into seven stages, from no cognitive decline to very severe cognitive decline. Each stage is accompanied by a list of common signs and symptoms, and some of the stages include an expected duration. The first three stages receive the diagnosis of no dementia, the fourth stage is called early-stage dementia, the fifth and sixth stages fall into the category of middle or mid-stage dementia, while the seventh stage receives the name late stage dementia.
Stage 1 is characterized by no cognitive decline and receives the diagnosis of no dementia. Signs and symptoms of this stage include the normal function and no memory loss. Stage 2 is characterized by very mild cognitive decline and receives the diagnosis of no dementia. Signs and symptoms of this stage include forgetting one’s own name and misplacing familiar objects, yet symptoms are not yet evident to doctors or family members. Stage 3 is characterized by mild cognitive decline and receives the diagnosis of no dementia. Signs and symptoms of this stage include increased forgetfulness, slight difficulty concentrating, decreased work performance, getting lost more often, and difficulty finding the right words. This is enough for family members to notice, and the average duration is 2 to 7 years.
Stage 4 is characterized by moderate cognitive decline and receives the diagnosis of early-stage dementia. Signs and symptoms of this stage include difficulty concentrating and completing tasks, socialization problems such as withdrawal from friends and family, no longer being able to manage finances or travel alone to new places, and being forgetful of recent events. At this stage, a physician can detect cognitive problems and the sufferer is in denial about his or her symptoms. The average duration of this stage is 2 years.
Stage 5 is characterized by moderately severe cognitive decline and receives the diagnosis of mid-stage dementia. Signs and symptoms of this stage include major memory deficiencies, forgetting details such as addresses and phone numbers, no longer knowing the time or date, lack of understanding for where they are, and needing assistance with activities of daily living such as bathing and dressing. The average duration of this stage is 1.5 years.
Stage 6 is characterized by severe cognitive decline and also receives the diagnosis of mid-stage dementia. Signs and symptoms of this stage include anxiety, delusions, compulsions, emotional changes, difficulty speaking, loss of bladder control, forgetful of recent events and major past events, changes in personality, unable to carry out activities of daily living without help, difficulty counting down from 10, and forgetful of names of close friends and relatives. The average duration of this stage is 2.5 years.
Stage 7 is characterized by very severe cognitive decline and receives the diagnosis of late-stage dementia. Signs and symptoms of this stage include the inability to speak or communicate, the loss of motor skills, the inability to walk, and the need for help with most daily activities. The average duration of this stage is between 1.5 and 2.5 years. Other scales for rating dementia include the Functional Assessment Staging Test and the Clinical Dementia Rating scale.