This information is provided by the Alzheimer’s Organization (alz.org).
Experts have documented common patterns of symptom progression that occur in many individuals with Alzheimer’s disease and developed several methods of “staging” based on these patterns.
Staging systems provide useful frames of reference for understanding how the disease may unfold and for making future plans. But it is important to note that not everyone will experience the same symptoms or progress at the same rate. People with Alzheimer’s die an average of four to six years after diagnosis, but the duration of the disease can vary from three to 20 years.
The framework for this section is a system that outlines key symptoms characterizing seven stages ranging from unimpaired function to very severe cognitive decline. This framework is based on a system developed by Barry Reisberg, M.D., Clinical Director of the New York University School of Medicine’s Silberstein Aging and Dementia Research Center.
Within this framework, we have noted which stages correspond to the widely used concepts of mild, moderate, moderately severe and severe Alzheimer’s disease. We have also noted which stages fall within the more general divisions of early-stage, mid-stage and late-stage categories.
|Stage 1:||No impairment (normal function)|
|Unimpaired individuals experience no memory problems and none are evident to a health care professional during a medical interview.|
|Stage 2:||Very mild cognitive decline (may be normal age-related changes or earliest signs of Alzheimer’s disease)|
|Individuals may feel as if they have memory loss and lapses, especially in forgetting familiar words or names or the location of keys, eyeglasses or other everyday objects. But these problems are not evident during a medical examination or apparent to friends, family or co-workers.|
|Stage 3:||Mild cognitive decline
Early-stage Alzheimer’s can be diagnosed in some, but not all, individuals with these symptoms
|Friends, family or co-workers begin to notice deficiencies. Problems with memory or concentration may be measurable in clinical testing or discernible during a detailed medical interview. Common difficulties include:
|Stage 4:||Moderate cognitive decline
(Mild or early-stage Alzheimer’s disease)
|At this stage, a careful medical interview detects clear-cut deficiencies in the following areas:
|Stage 5:||Moderately severe cognitive decline
(Moderate or mid-stage Alzheimer’s disease)
|Major gaps in memory and deficits in cognitive function emerge. Some assistance with day-to-day activities becomes essential. At this stage, individuals may:
|Stage 6:||Severe cognitive decline
(Moderately severe or mid-stage Alzheimer’s disease)
|Memory difficulties continue to worsen, significant personality changes may emerge and affected individuals need extensive help with customary daily activities. At this stage, individuals may:
|Stage 7:||Very severe cognitive decline
(Severe or late-stage Alzheimer’s disease)
|This is the final stage of the disease when individuals lose the ability to respond to their environment, the ability to speak and, ultimately, the ability to control movement.