10 U.S. Counties Where Alzheimer’s Disease Is Most Common

The East and Southeast portions of the U.S. are home to the highest percentage of people with Alzheimer’s dementia.

Both a higher percentage of older residents and a greater prevalence of Black and Hispanic residents in those regions might be responsible for the increased occurrence of the disease there, according to research presented at the Alzheimer’s Association International Conference 2023 in Amsterdam.

An estimated 6.7 million Americans have Alzheimer’s disease. Black Americans are about twice as likely — and Hispanic individuals about 1.5 times as likely — to have Alzheimer’s or other dementias as white residents, the researchers say.

Following are the U.S. counties where Alzheimer’s disease is most common.

El Paso County, Texas

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 15%
• Total population: 868,763 as of 2022
• Population age 65 or older: 13.1%

El Paso County sits at the edge of western Texas and is bordered by the Franklin Mountains in the north and the Hueco Mountains in the east. Because of the region’s strong ties to the military, it describes itself as the “veterans capital of the United States.”

Imperial County, California

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 15%
• Total population: 178,713 as of 2022
• Population age 65 or older: 13.8%

Imperial County was the last to be established in the state of California. It is responsible for half of the nation’s winter vegetable crop.

Orangeburg County, South Carolina

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 15.2%
• Total population: 83,094 as of 2022
• Population age 65 or older: 21.1%

Orangeburg County is located near the center of South Carolina. It is home to South Carolina State University.

Dougherty County, Georgia

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 15.3%
• Total population: 82,966 as of 2022
• Population age 65 or older: 17.3%

Founded in 1853 and named after a judge — Charles Dougherty of Athens — Dougherty County is renowned nationally as a top spot for hunting and fishing.

Orleans Parish, Louisiana

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 15.4%
• Total population: 369,749 as of 2022
• Population age 65 or older: 17.4%

Orleans Parish is named after the Duke of Orleans, the regent of France. It is home to one of the nation’s most festive cities, New Orleans.

Hinds County, Mississippi

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 15.5%
• Total population: 217,730 as of 2022
• Population age 65 or older: 16.5%

Hinds County is home to Mississippi’s capital, Jackson. Two rivers — the Big Black and the Pearl — help define the county’s borders.

Prince George’s County, Maryland

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 16.1%
• Total population: 946,971 as of 2022
• Population age 65 or older: 15.3%

Prince George’s County is located just minutes from Washington, D.C., and is home to Six Flags America among other attractions.

Bronx County, New York

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 16.6%
• Total population: 1.38 million as of 2022
• Population age 65 or older: 14.4%

Founded in 1914, Bronx County was the last of New York’s 62 counties to be incorporated. It is the third most densely populated county in the U.S.

Baltimore City, Maryland

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 16.6%
• Total population: 569,931 as of 2022
• Population age 65 or older: 15.7%

Baltimore City separated from Baltimore County in 1851. Since then, it has been recognized as being on par with county jurisdictions in the state.

Miami-Dade County, Florida

This county’s:

• Estimated prevalence of Alzheimer’s disease among people who are 65 or older: 16.6%
• Total population: 2.67 million as of 2022
• Population age 65 or older: 17.2%

Miami-Dade County is home to Miami, known for its glamour and beaches. The county’s population of nearly 2.7 million is bigger than the populations of 15 U.S. states.