Complications (1)
- Alzheimer's: Managing sleep problems
Definition (1)
- Early-onset Alzheimer's: When symptoms begin before 65
Risk factors (2)
- Diabetes and Alzheimer's linked
- Alzheimer's: Is it in your genes?
Symptoms (3)
- Alzheimer's or depression: Could it be both?
- Memory loss: When to seek help
- Alzheimer's stages: How the disease progresses
Tests and diagnosis (3)
- Diagnosing Alzheimer's: An interview with a Mayo Clinic specialist
- Positron emission tomography (PET) scan
- SPECT scan
Treatments and drugs (3)
- Alzheimer's: Getting the most from medical appointments
- Alzheimer's drugs slow progression of disease
- Alzheimer's treatments: What's on the horizon?
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Get StartedAlzheimer's stages: How the disease progresses
Alzheimer's disease can last more than a decade. See what types of behaviors are common in each of the stages as the disease progresses.
By Mayo Clinic staffAlzheimer's disease typically develops slowly and causes a gradual decline in cognitive abilities, usually over a span of seven to 10 years. It eventually affects nearly all brain functions, including memory, movement, language, behavior, judgment and abstract reasoning.
Dividing the progression of Alzheimer's disease into stages can help you plan for the future, but remember that not everyone will experience the same symptoms or progress at the same rate. While each individual is different, the progression of his or her disease can be roughly divided into three stages — mild, moderate and severe.
Mild Alzheimer's disease
People in the early stage of Alzheimer's may experience memory loss, lapses of judgment and subtle changes in personality. They often have decreased attention span and less motivation to complete tasks. In addition, they may resist change and new challenges, and get lost even in familiar places.
While everyone occasionally forgets words or names during conversations, this problem occurs with increasing frequency in people with mild Alzheimer's. They may substitute or make up words that sound like or mean something like the forgotten word. They sometimes even avoid talking to keep from making mistakes and appear subdued or withdrawn — especially in socially or mentally challenging situations.
They may also put things in very odd places. For example, a wallet may end up in the freezer, or clothes may go into the dishwasher. They may ask repetitive questions or hoard things of no value. When frustrated or tired, they may become uncharacteristically angry.
Moderate Alzheimer's disease
In the middle stage of Alzheimer's, people can't organize thoughts or follow logical explanations. They lose the ability to follow written instructions and often need help choosing proper clothing for the season or occasion. Eventually, they'll require help getting dressed because their confusion may cause them to put their pajamas on over their daytime clothes or their shoes on the wrong feet. They may also have episodes of urinary or fecal incontinence.
It's usually during this stage that people start having problems recognizing family members and friends. They may mix up identities — thinking a son is a brother or that a spouse is a stranger. They may become confused about where they are and what day, season or year it is. They become unable to recall their address or phone number.
Because they lack judgment and tend to wander, people with moderate Alzheimer's disease aren't safe on their own. They may exhibit restless, repetitive movements in late afternoon, or continually repeat certain stories, words or motions, such as tearing tissues.
Problems with communication worsen during the moderate stage of Alzheimer's. This can lead to a variety of challenging behaviors, including:
- Paranoia that sometimes provokes accusations of infidelity or stealing
- Agitation, frustration or anger that can lead to cursing, kicking, hitting, biting, screaming or grabbing
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