In one of the most sweeping studies of its kind, researchers have discovered some startling regional disparities in dementia rates among U.S. veterans.
Appearing online first on JAMA Neurology, the paper reports on an exhaustive analysis of more than 1.2 million medical records of veterans without a dementia diagnosis. All of the veterans were 65 and older and had received treatment at the Veterans Health Administration (VHA).
The analysis, which included data from more than 20 years, provides further evidence that something as simple as geography can influence one’s dementia risk.
Southeast Carries Highest Dementia Burden
The University of California-San Francisco researchers found out that incidence of dementia shot up or fell off – depending on where the veterans lived.
The Mid-Atlantic region boasted the lowest rate of new dementia diagnoses at 11.2 cases per 1,000 person-years. On the other end of the spectrum, the Southeast included the nation’s highest rate of new cases, at 14 per 1,000 person-years.
Even after adjusting for demographics, including rurality and cardiovascular comorbidities, the Southeast still struggled with a 25% higher dementia incidence compared to the Mid-Atlantic region. The researchers noted similarly elevated rates in the Northwest and Rocky Mountain regions.
“While the absolute differences in dementia incidence were modest, such differences can have substantial public health implications when applied to large populations, underscoring the importance of region-specific prevention and intervention efforts in higher-risk areas,” the researchers wrote.
A Closer Look at the Data
Using regional categories organized by the U.S. Centers for Disease Control and Prevention (CDC), the authors looked at dementia rates across 10 different regions.
Among the 1,268,599 participants, the Southeast, South, and Rocky Mountains all posted much higher dementia rates, while the Great Lakes and Northeast regions featured rates closer to the national average. The Mid-Atlantic region stood alone with the lowest incidence of dementia.
The researchers suspect that environmental, cultural, or social factors might all play larger than expected roles in influencing dementia rates.
“Quality of education, early life conditions, and environmental exposures may be among those factors,” first author Christina Dintica, PhD, added.
The Southeast and South, for example, had both higher rates of hypertension and diabetes – along with fewer college-educated residents in many areas.
But adjustments for these factors only narrowed the gap slightly. That, the authors argue, implies that other factors could be at play. For instance, social isolation, access to specialty care, and historical healthcare inequities endemic to rural areas could all add to later-stage diagnoses or higher disease burdens.
While some might speculate that differences in diagnostic intensity could be skewing the data, the authors point out that the VHA’s relatively uniform care model should minimize such variation compared to other systems, such as Medicare.
Policy and Dementia Prevention
While the study population isn’t the best representation of the public at large, veterans still offer valuable insight. To take one example, the centralized documentation of their care makes it easier for researchers to access a large-scale, consistent repository of data from multiple locations and diverse backgrounds.
This investigation highlights a desperate need for region-specific public health strategies. Targeted interventions in high-risk regions, the authors insist, should include improving cardiovascular care, expanding telehealth services to underserved rural areas, and investing in community-level health education programs.
The study also raises the possibility of integrating neighborhood-level data, geospatial analyses, and environmental exposure metrics into future dementia research projects.
As the nation’s population ages, the urgency to develop more effective, tailored strategies to prevent and manage dementia will only get more intense.
Further Reading
US Dementia Cases Will Double By 2060
