Alzheimer’s Prevalence

Researchers rank the U.S. counties with the highest rates of Alzheimer’s disease

The Alzheimer’s Association released a first-of-its-kind study in July, ranking all 3,142 U.S. counties — by Alzheimer’s disease prevalence. About 6.7 million Americans have this form of dementia.

Most counties with the highest Alzheimer’s prevalence are in the Eastern and Southeastern U.S., though California and Illinois rank among the top 10 states with the highest Alzheimer’s rates. Researchers used data from the Chicago Health and Aging Project and the National Center for Health Statistics to create the rankings.

Kumar Rajan, PhD, director of the Rush Institute for Healthy Aging, is one of the study authors. He says the paper can help counties plan how to allocate resources to address Alzheimer’s disease. “If there are public health programs on prevention, they can focus on how strong these programs need to be and how many people would potentially be needing caregiving,” Rajan says.

Though people commonly recognize age as an Alzheimer’s risk factor, race plays a role, too. Black people in the U.S. are about twice as likely to have dementia compared to white people, and older Hispanic people are 1.5 times as likely.

The 10 counties (with at least 10,000 people over age 65) that have the highest rates of Alzheimer’s disease are:

• Miami-Dade County, Florida. (16.6%)
• Baltimore City, Maryland (16.6%)
• Bronx County, New York (16.6%)
• Prince George’s County, Maryland (16.1%)
• Hinds County, Mississippi (15.5%)
• Orleans Parish, Louisiana (15.4%)
• Dougherty County, Georgia (15.3%)
• Orangeburg County, South Carolina (15.2%)
• Imperial County, California (15.0%)
• El Paso County, Texas (15.0%)

While the study doesn’t directly address potential causes or treatments, Rajan says there are things everybody can do to reduce their risk of Alzheimer’s disease, no matter where they live. “The first thing is prevention — so healthy living,” Rajan says. “Be physically active, be cognitively active, try to reduce as many chronic health conditions that you have, reduce cardiovascular risk. Anything you can do to be healthy, those factors really help.”