Residents of the Rocky Mountains and the Northwest United States may face a heightened risk of dementia, according to a recent study.
A team of researchers from California divided the U.S. into ten regions to analyze and compare dementia rates across these areas.
The Mid-Atlantic region, including states like Pennsylvania, New Jersey, and West Virginia, served as a baseline for this comparison due to its overall low rates of dementia.
The findings indicated that individuals in the Southeast—encompassing states like Kentucky, Tennessee, Alabama, and Mississippi—exhibited the highest likelihood of developing dementia, experiencing a 25 percent increased risk compared to the Mid-Atlantic baseline.
Following closely behind were residents of the Northwest states such as Alaska and Idaho, as well as those around the Rocky Mountains, with a 23 percent elevated risk.
In southwestern states, including California, the risk was elevated by 13 percent. Conversely, northeastern states like New York had the lowest risk, with only a 7 percent increase.
The study, conducted by researchers from the University of California San Francisco (UCSF), attributed these disparities largely to socioeconomic factors, including educational quality and exposure to environmental toxins.
While the team noted that further research is necessary, their findings highlight regions that might need additional focus regarding education, prevention, and treatment efforts for dementia.
Dr. Kristine Yaffe, one of the senior authors of the study, emphasized the importance of understanding these regional disparities and tailoring prevention strategies accordingly.
In the United States, approximately 8 million adults live with some form of dementia, with about 500,000 new diagnoses each year. Experts predict that cases could increase by a million annually by 2060, while some estimates suggest that up to 12.7 million individuals may be diagnosed by 2050.
This rise could result from various factors, including underreporting, a growing aging population, and increasing rates of conditions like heart disease and obesity, both of which affect blood vessels in the brain and can contribute to dementia.
Alzheimer’s disease remains the most common type of dementia, accounting for around 6 million cases.
The study, published in JAMA Neurology, analyzed data from 1.2 million veterans over the age of 65 who received care through the Veterans Affairs (VA) health system between 1999 and 2021. Participants were generally followed for an average of about 13 years.
On average, participants were 74 years old, predominantly male (98 percent), and mostly white (86 percent). In general, the average age for a dementia diagnosis in the U.S. is 83.
The researchers utilized data defined by the CDC to categorize regions: Northeast, Great Lakes, Mid-Atlantic, South Atlantic, Southeast, South, Midwest, Rocky Mountains, Southwest, and Northwest.
The Mid-Atlantic had the lowest dementia rate, with only 11 cases per 1,000 people. In contrast, the Southeast reported 14 cases per 1,000, marking a 25 percent increased risk compared to the Mid-Atlantic.
The Northwest and Rocky Mountain regions recorded rates of 13 per 1,000, placing them at a 23 percent heightened risk compared to the Mid-Atlantic.
Residents of the Southwest had a 13 percent increased risk, reporting 12 cases per 1,000. The Midwest and Great Lakes regions also saw a similar increase. Meanwhile, the Northeast had the smallest increase, with 12 per 1,000 and a 7 percent risk elevation from the Mid-Atlantic.
The researchers underscored that socioeconomic factors likely contribute to these regional differences, particularly in southeastern states. Dr. Christina Dintica, the first author, pointed out the roles of education quality, early life conditions, and environmental exposures.
States like Kentucky and Mississippi have higher rates of conditions such as diabetes, heart disease, and obesity, all of which can affect brain health negatively. They also face environmental hazards from industrial activities that may lead to toxic exposures linked with dementia.
Military veterans, in general, exhibit a higher risk for dementia, often attributed to increased occurrences of traumatic brain injuries (TBIs) that can damage both brain cells and blood vessels. Some TBIs are also correlated with increased levels of tau and amyloid proteins, which are known to contribute to Alzheimer’s disease.
Additionally, veterans commonly deal with post-traumatic stress disorder (PTSD), which can lead to inflammation in the brain and further damage memory-related structures. Older veterans in the study might also have faced exposure to Agent Orange during the Vietnam War, a factor that prior research links to a doubling in dementia risk.
It’s worth noting that the study does have limitations, particularly given its focus on veterans and its overwhelmingly male participant base.
