Skip to content

    Alzheimer's Disease Health Center

    Select An Article

    Types of Alzheimer's Disease

    Font Size
    A
    A
    A

    Nearly everyone with Alzheimer’s disease will eventually have the same symptoms -- memory loss, confusion, trouble with once-familiar tasks, and making decisions. Though the effects of the disease are similar, there are two main types.

    • Early-onset Alzheimer's. This type happens to people who are younger than age 65. Often, they’re in their 40s or 50s when they’re diagnosed with the disease. It’s rare -- up to 5% of all people with Alzheimer's have early-onset. People with Down syndrome have a higher risk for it.

      Scientists have found a few ways in which early-onset Alzheimer’s is different from other types of the disease. People who have it tend to have more of the brain changes that are linked with Alzheimer’s. The early-onset form also appears to be linked with a defect in a specific part of a person’s DNA: chromosome 14.  A form of muscle twitching and spasm, called myoclonus, is also more common in early-onset Alzheimer's.
    • Late-onset Alzheimer's. This is the most common form of the disease, which happens to people age 65 and older. It may or may not run in families. So far, researchers haven’t found a particular gene that causes it. No one knows for sure why some people get it and others don’t.

    Familial Alzheimer's disease (FAD) is a form of Alzheimer's disease that doctors know for certain is linked to genes. In families that are affected, members of at least two generations have had the disease. FAD makes up less than 1% of all cases of Alzheimer's. Most people who have early onset Alzheimer's have FAD.

    Recommended Related to Alzheimer's

    How to Manage "Sundowning"

    When you are with someone who has Alzheimer's disease, you may notice big changes in how they act in the late afternoon or early evening. Doctors call it sundowning, or sundown syndrome. Fading light seems to be the trigger. The symptoms can get worse as the night goes on and usually get better by morning. Although you may not be able to stop it completely, you can take steps to help manage this challenging time of day so you both sleep better and are less tired during the day. Let your loved one’s...

    Read the How to Manage "Sundowning" article > >

     

    WebMD Medical Reference

    Reviewed by Melinda Ratini, DO, MS on July 30, 2016
    Next Article:

    Today on WebMD

    Remember your finger
    When it’s more than just forgetfulness.
    senior man with serious expression
    Which kinds are treatable?
     
    senior man
    Common symptoms to look for.
    mri scan of human brain
    Can drinking red wine reverse the disease?
     
    Checklist
    ARTICLE
    eating blueberries
    ARTICLE
     
    clock
    Article
    Colored mri of brain
    ARTICLE
     
    Human brain graphic
    ARTICLE
    mature woman
    ARTICLE
     
    Woman comforting ailing mother
    ARTICLE
    Senior woman with serious expression
    ARTICLE