Alzheimer’s disease is a neurodegenerative disease and type of dementia characterized by memory loss, poor judgment and decision-making, and a decreasing ability to complete familiar tasks. There are four stages of the disease, each with progressing levels of cognitive decline.

Even as long as a decade before symptoms appear, a person can have preclinical Alzheimer’s, in which plaques begin accumulating in the brain, but cognitive changes aren’t apparent.

A person with Alzheimer’s in the second and third stages may repeat questions, get lost, or have difficulty reading, writing, or thinking logically. Severe or late-stage Alzheimer’s involves an inability to communicate, a loss of awareness of surroundings, and a loss of control over bodily functions.

When do most people get Alzheimer’s disease?

For more than 90% of those who have Alzheimer’s in the United States, disease onset occurs in their mid-60s. This is referred to as late-onset Alzheimer’s.

Early-onset Alzheimer’s can begin in a person’s 30s. It is rare and accounts for less than 10% of Alzheimer’s cases, according to the National Institute on Aging. About 200,000 people in the US have ​​early-onset Alzheimer’s disease.

Older age increases the risk of Alzheimer’s. After age 65, the number of people with Alzheimer's doubles every five years, according to the Centers for Disease Control and Prevention (CDC). For those 85 and older, the National Institute on Aging estimates that about one-third could have Alzheimer’s disease.

Are certain races more likely to get Alzheimer’s disease?

In addition to the disease disproportionately impacting women, Hispanic and African American populations have a higher likelihood of being diagnosed with Alzheimer’s.

As of 2023, 6.7 million Americans over age 65 have Alzheimer’s. The CDC expects those diagnoses to hit 14 million by 2060. However, Hispanic people will be diagnosed at a rate seven times the total population estimates, and cases among African American people will increase at a rate four times the total population estimates.

How does dementia vary by state?

The CDC tracks how many adults experience cognitive decline over time. It is monitored as a subjective measure of whether cognitive decline or memory loss is happening more often or is getting worse over a 12-month period. This data includes those with Alzheimer’s but also includes those experiencing kinds of dementia.

Dementia is not a disease but rather an umbrella term for cognitive decline that can interfere with a person’s ability to remember information and make decisions. Alzheimer’s is just one kind of dementia. Other kinds of dementia include conditions like vascular dementia and Lewy body dementia, which have similar symptoms to Alzheimer’s but different causes.

Several southern states and Utah, Colorado, Michigan, Maryland, and Washington, DC, have the highest percentages of populations (14.1–16.5%) 65 and older reporting worsening cognitive function over the previous 12 months.

Where does this data come from?

The CDC has an Alzheimer’s Disease Program, which maintains the Cognitive Decline and Caregiving Modules, based on data from the Behavioral Risk Factor Surveillance System. The Alzheimer’s Disease Program has information on characteristics of the disease, who it’s likely to affect, and state-level and population trends regarding dementia.

The National Institute on Aging provides information on the causes and genetic features of Alzheimer’s disease, as well as signs of the disease. Data on disease frequency by gender is an academic study published in a medical journal housed by The National Library of Medicine.

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Page sources and methodology

All of the data on the page was sourced directly from government agencies. The analysis and final review was performed by USAFacts.

  • Centers for Disease Control and Prevention

    Behavioral Risk Factor Surveillance System

  • National Institute on Aging

    What Are the Signs of Alzheimer's Disease?