Where You Live May Impact Risk, Study Finds

• A large study of U.S. veterans has found regional differences in dementia risk.
• The Southeast region had the highest risk, while the Mid-Atlantic had the lowest.
• Experts say healthcare resources should be tailored to meet regional differences.
• There are also lifestyle choices that individuals can make to reduce their dementia risk.

A new nationwide study reveals that your risk of dementia might vary depending on where you live.

Dementia is an incurable condition that causes a progressive decline in a person’s cognitive abilities, including thinking, memory, and behavior.

The researchers found significant regional differences in dementia rates among older U.S. veterans, which they say highlights the need for targeted healthcare strategies.

The findings, published online on June 9 in JAMA Neurology, show that among veterans ages 65 and older, dementia incidence was lowest in the Mid-Atlantic region and highest in the Southeast.

Even after adjusting for factors like age, race, education, rural living, and heart health, the Southeast region showed up to 25% higher dementia rates, with the Northwest and Rocky Mountains regions at 23%.

Experts suggest that socioeconomic factors, healthcare quality, lifestyle, and environmental exposures may contribute to these disparities.

The findings underscore the importance of region-specific public health interventions to better support those at greater risk.

As dementia continues to affect millions nationwide, understanding these geographic patterns could help reduce risk and improve care efforts for vulnerable populations.

This large study examined how rates of new dementia cases vary across different regions of the United States among older veterans receiving care through the Veterans Health Administration (VHA).

The researchers followed over 1.2 million dementia-free veterans aged 65 and older for an average of about 12.6 years to see where dementia diagnoses occurred most frequently.

They divided the country into 10 regions based on Centers for Disease Control and Prevention (CDC) definitions and tracked new dementia diagnoses using medical codes recorded during veterans’ visits to VHA facilities.

The study also considered factors such as age, sex, race, education level in their neighborhoods, whether veterans lived in rural or urban areas, and if they had other health problems like diabetes, high blood pressure, or heart disease.

The researchers found that dementia incidence rates differed significantly by region. The Mid-Atlantic region (including states like Pennsylvania, Maryland, and New Jersey) had the lowest dementia incidence at about 11.2 cases per 1,000 person-years.

In contrast, the Southeast (including Kentucky, Tennessee, Alabama, and Mississippi) had the highest rate, with about 14.0 cases per 1,000 person-years — a roughly 25% higher risk compared to the Mid-Atlantic.

In addition to the 23% higher rates in the Northwest and Rocky Mountains, other regions with higher dementia rates included:

• South: 18%
• South Atlantic: 12%
• Midwest: 12%

The remaining regions had a less than 10% difference.

These differences remained even after adjusting for important factors such as age, sex, race and ethnicity, education level (measured by the percentage of college-educated adults in the area), rural versus urban residence, and cardiovascular health conditions like hypertension and diabetes.

This suggests that other region-specific factors might be contributing to the varying dementia risks.

Possible contributors to these regional differences include socioeconomic disparities, lifestyle and environmental factors, access to and quality of healthcare, and diagnostic practices. For example, regions with higher dementia rates tended to have lower educational attainment and higher rates of conditions like stroke and hypertension.

Living in a rural area was associated with some increased risk, but did not fully explain the differences.

The authors also noted that the VHA system provides relatively even access to healthcare, so differences in healthcare availability might be less of a factor than in the general population.

Overall, the study highlights that dementia risk is not uniform across the United States and that public health strategies and healthcare resources should be tailored to address these regional differences to better support populations at higher risk.

Logan DuBose, MD, co-founder of Olera, who was not involved in the study, explained that several factors can influence a person’s risk of dementia. These may include:

“So as we look at this study’s finding — that the Southeast has 14 cases per 1,000 person-years while the Mid-Atlantic has only 11.2 cases per 1,000 person-years — even after adjusting for demographics, rurality, and cardiovascular conditions, it’s interesting to consider how these environmental and social factors I mention are at play and may create regional patterns in dementia risk like the study showed,” DuBose told Healthline.

DuBose added, however, that the population consisted entirely of veterans followed from October 1999 to September 2021, which might be a confounding variable since some U.S. regions are more veteran-friendly than others. For example, there are more military bases and places where they can access VA healthcare services.

“That said, the large number of participants and sound study protocol still seems to make it likely that there is in fact a generalizable, statistically significant, and likely clinically significant regional difference in dementia risk,” DuBose noted.

Just because you live in a particular geographic region doesn’t necessarily mean you will develop dementia.

As Raj Dasgupta, MD, chief medical advisor for Garage Gym Reviews, who was also not involved in the study, said that research like this helps us to “connect the dots” and identify patterns.

“If we know where dementia is hitting hardest, we can focus on bringing more support and resources to those communities,” Dasgupta told Healthline.

“It’s not just about the numbers, it’s about giving people in those areas a better shot at early diagnosis, treatment, and [risk reduction],” he added.

Dasgupta noted that there is plenty we can do on the individual level to reduce the risk of developing dementia.

“Basically, what’s good for your heart tends to be great for your brain too. Small, consistent habits really add up when consistent over time.”