Alzheimer’s disease affects individuals in very different ways, though there are common symptoms and changes that occur as it evolves. How Alzheimer’s progresses is crucial for the earliest detection possible and the implementation of treatment and care.

To date, experts have identified three major stages: preclinical, mild to moderate and severe. Learn about the signs you may notice in an individual as Alzheimer’s moves through these major stages, per information from the National Institute on Aging, WebMD and the Alzheimer’s Association.

Stage 1: Preclinical Alzheimer’s

Symptoms: None to very mild cognitive decline.

Potential changes: In this stage, there are typically no symptoms, save for minor memory lapses like forgetting common words or where belongings are stored. A medical exam would show no signs of dementia, but researchers are working on biomarker tests to deduce Alzheimer’s before symptoms become apparent. That’s because some studies indicate brain changes that foreshadow Alzheimer’s take place during this stage – which may begin as many as 20 years before symptoms show themselves.

Stage 2: Mild to Moderate Cognitive Decline

Symptoms: Apparent difficulty remembering things and concentrating, both of which worsen over the years.

Potential Changes: The effects of Alzheimer’s disease become much more apparent in the second major stage. Some changes that may occur include:

– Difficulty remembering words and names

– Trouble getting work done or participating in social settings

– Losing or misplacing items

– More problems planning and keeping things organized

– Shifts in personality

– Challenges remembering recent events

– Poor judgments

– Forgetting personal history

– Becoming moody or withdrawn

At this point, a doctor’s exam would clearly display such changes, all of which point to Alzheimer’s. Struggles with memory and language will continue to worsen at this stage. A move to a memory care setting may be necessary at this point.

Stage 3: Severe Cognitive Decline

Symptoms: Unable to communicate or take care of oneself, alongside physical declines.

Potential Changes: At this phase in how Alzheimer’s progresses, changes become more drastic and dire:

– Loss of coherent speech

– Wandering or getting lost

– Difficulty controlling bodily functions

– Weight loss

– Not remembering how to swallow

– Major personality and behavior changes, such as delusions and paranoia

– Recognizing faces but not names

With severe Alzheimer’s, the brain struggles greatly to tell the body what to do. All independence is lost, meaning individuals become entirely dependent on others for care, including activities of daily living like bathing, dressing and eating. Even completing the most basic of tasks, including walking, require assistance. As time passes, someone in this stage may end up spending most of his or her time in bed as Alzheimer’s progresses to its most severe levels.