Alzheimer’s disease is one of the biggest health challenges facing older adults around the world. It slowly damages the brain, causing memory loss, confusion, and changes in thinking and behavior.
Over time, people with Alzheimer’s may struggle to recognize loved ones, carry out everyday tasks, or live independently. While scientists have learned a great deal about the disease, there is still no cure. That is why understanding where Alzheimer’s is most common can help governments and healthcare systems better prepare for the future.
A new study has found that Alzheimer’s disease is especially common in the eastern and southeastern parts of the United States. States such as Florida and Maryland, along with parts of New York and nearby areas, have some of the highest percentages of older adults living with the disease.
The research was presented at the Alzheimer’s Association International Conference in Amsterdam and was also published in the journal Alzheimer’s & Dementia.
The study was led by Dr. Kumar Rajan, a professor of internal medicine at Rush Medical College in Chicago. His team wanted to create the clearest picture yet of how Alzheimer’s is spread across the United States.
Instead of looking only at states, they examined every one of the country’s 3,142 counties. To do this, they combined information from the long-running Chicago Health and Aging Project with U.S. government population estimates. This allowed them to estimate how common Alzheimer’s is in each county.
The results showed that some counties have much higher rates than others. The highest estimated percentage of older adults living with Alzheimer’s was found in Miami-Dade County, Florida, Baltimore City, Maryland, and Bronx County, New York. In each of these places, about 16.6 percent of people aged 65 and older were estimated to have Alzheimer’s disease.
Several other counties also had very high rates. These included Prince George’s County in Maryland, Hinds County in Mississippi, Orleans Parish in Louisiana, Dougherty County in Georgia, Orangeburg County in South Carolina, Imperial County in California, and El Paso County in Texas.
In all of these places, around 15 to 16 percent of older adults were living with Alzheimer’s, well above the national average.
The researchers believe several factors help explain these differences. One important reason is age. Alzheimer’s becomes much more common as people grow older. Areas with larger populations of seniors naturally have more people affected by the disease.
Race and ethnicity may also contribute to the pattern. Previous research has shown that older Black Americans are about twice as likely as older white Americans to develop Alzheimer’s disease. Older Hispanic adults are about one and a half times more likely to develop the condition.
Many counties with the highest estimated rates have large Black or Hispanic populations, which may partly explain the findings. Scientists are still studying why these differences exist. They are likely caused by a combination of health, social, economic, and environmental factors rather than a single cause.
Dr. Rajan explained that Alzheimer’s is a complex disease. Many different factors work together to increase a person’s risk. These include age, family history, genetics, heart health, diabetes, blood pressure, education, lifestyle, and the environment where a person lives. No single factor can fully explain why someone develops the disease.
The findings are important because they can help public health officials decide where to send resources. Communities with higher numbers of people living with Alzheimer’s may need more doctors, nurses, memory clinics, home care services, support groups, and programs for family caregivers.
Planning ahead is becoming increasingly important because the number of people with Alzheimer’s continues to rise as the population ages.
Today, about 6.7 million Americans are living with Alzheimer’s disease. Experts expect this number to increase significantly over the coming decades. Some western and southwestern parts of the country are also expected to see rapid growth as their older populations expand.
Matthew Baumgart from the Alzheimer’s Association said studies like this help healthcare leaders understand where future demand for services will be greatest. They also highlight the importance of providing culturally appropriate care and support for families from different backgrounds.
Although Alzheimer’s cannot yet be prevented completely, research suggests that healthy habits may help lower the risk.
Regular exercise, controlling blood pressure and diabetes, eating a healthy diet, staying socially active, keeping the brain mentally engaged, getting enough sleep, and avoiding smoking may all support long-term brain health. Scientists continue to study better ways to prevent, diagnose, and treat the disease.
This new county-by-county map gives one of the most detailed pictures yet of where Alzheimer’s has the greatest impact in the United States. By identifying communities with the highest need, researchers hope healthcare systems can better prepare for the growing number of people and families who will be affected in the years ahead.
If you care about Alzheimer’s, please read studies about the likely cause of Alzheimer’s disease , and new non-drug treatment that could help prevent Alzheimer’s.
For more health information, please see recent studies about diet that may help prevent Alzheimer’s, and results showing some dementia cases could be prevented by changing these 12 things.
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