With the emergence of new treatments for Alzheimer’s disease and various types of dementia, a recent study highlights that obtaining a diagnosis necessary to access these treatments might hinge on your geographical location.
With the emergence of new treatments for Alzheimer’s disease and various types of dementia, a recent study highlights that obtaining a diagnosis necessary to access these treatments might hinge on your geographical location.
The yearly rate of individuals receiving a fresh dementia diagnosis varies significantly across different U.S. regions, according to the study.
These regional disparities are even more pronounced among younger individuals at risk for dementia, particularly those aged 66 to 74, as well as Black or Hispanic populations.
Interestingly, a person could be up to twice as likely to receive a dementia diagnosis in certain areas of the U.S. compared to others. The results indicate that the likelihood of receiving a diagnosis might be more related to the healthcare system than to personal factors influencing dementia risk.
A formal diagnosis is essential for accessing new advanced tests and treatments for dementia, many of which focus on slowing the progression of the condition during its initial stages, known as mild cognitive impairment or mild Alzheimer’s disease.
This study specifically examines regional variations in the “diagnostic intensity” of dementia, a difference that persists even when accounting for various dementia risk factors and demographic variations.
Conducted by researchers from the University of Michigan, the study is published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
“These findings go beyond just demographic variations in risk and point to system-level healthcare differences that can be addressed,” stated Julie Bynum, M.D., M.P.H., a geriatrician and healthcare researcher at U-M who spearheaded the study.
“The takeaway is clear: the chances of receiving a dementia diagnosis differ significantly from one place to another, influenced by factors such as healthcare practices and the care-seeking behaviors of individuals,” explained Bynum, who also serves as a professor of internal medicine at U-M Medical School. “The encouraging news is that we can act on these insights once identified.”
Bynum and her colleagues employed data from 4.8 million Medicare beneficiaries over the age of 66 to conduct the study.
While nearly 7 million Americans currently hold a dementia diagnosis, millions more likely show symptoms but remain undiagnosed.
Insurance coverage for new biomarker tests, brain imaging scans, and medications that slow dementia hinges on a formal diagnosis. Even for those not qualifying for these treatments, having an official diagnosis can help them access specialized care and support for both patients and their caregivers.
Exploring more than just risk factors: Details about the study
Researchers have identified numerous factors contributing to a person’s heightened risk of developing Alzheimer’s and other dementia forms. These include prolonged high blood pressure, high cholesterol, use of tobacco or alcohol, lower levels of formal education, and decreased social interaction or sleep.
However, this new study uniquely demonstrates that regional differences in diagnoses cannot solely be attributed to varying dementia risk in different populations.
The research analyzed diagnoses across 306 hospital referral regions outlined in the Dartmouth Atlas of Health Care, commonly used in various studies. Each HRR includes at least one hospital equipped to perform advanced heart and brain surgeries; these locations were selected due to the necessity for specialized services in dementia diagnosis and treatment.
Of the total population studied, 143,029 individuals were diagnosed with Alzheimer’s or another form of dementia in 2019, while the remaining 356,656 had been diagnosed prior.
This indicates that approximately 7% of people with traditional Medicare have a dementia diagnosis at any given time, with 3% receiving a new diagnosis each year, averaging around 83 years at diagnosis.
The researchers calculated new diagnosis rates and total numbers for each HRR as of 2019. The prevalence of diagnosed dementia varied, ranging from 4% to 14% depending on the HRR, and the rate of new diagnoses was between 1.7% and 5.4%.
The study categorized data into three age groups—66 to 74, 75 to 84, and 85 and older—and analyzed rates among individuals identified as white, Black, or Hispanic. They also examined the percentage of populations within each HRR that had less than a high school education, smoked, or struggled with obesity or diabetes—additional risk factors for dementia.
The researchers incorporated general diagnostic intensity related to a range of chronic diseases within each HRR.
With consideration of these factors, they calculated predicted rates of diagnosis for new and existing Alzheimer’s and dementia cases, termed “diagnostic intensity.”
Compared to the national average, individuals residing in low-diagnostic-intensity regions are 28% less likely to be diagnosed, whereas those in high-diagnostic-intensity areas are 36% more likely to receive a diagnosis.
The highest concentration of diagnosed dementia cases appeared in the southern U.S., a region already known for higher risks of strokes and cardiovascular diseases.
However, the South was not uniformly high in dementia diagnoses once adjustments for other factors were made.
Regional implications for change
Bynum explains that the results may reflect differences in clinical practices—such as how frequently primary care doctors screen patients for early signs of dementia or the availability of specialists for formal diagnoses.
Cultural or personal factors might also affect an individual’s likelihood to seek medical care, schedule appointments due to memory concerns, or proactively address memory-related issues with healthcare providers.
While researchers cannot definitively determine whether the differences indicate underdiagnosis or overdiagnosis, areas with lower-than-expected diagnosis rates for dementia might leverage these findings to identify barriers preventing accurate diagnoses.
“The focus should be on identifying individuals with cognitive issues sooner, yet our data indicates that the younger demographic of Medicare participants shows the greatest variation,” said Bynum. “For communities and health systems, this should encourage initiatives aimed at increasing knowledge and access to services. For individuals, it emphasizes the need to advocate for cognitive assessments and support.”
Bynum mentions that Medicare includes a cognitive screening as part of the annual wellness visit for each enrollee.
Additionally, the new GUIDE model for dementia care launched by Medicare may improve the quality of care as it incentivizes healthcare practices to better coordinate dementia care and provide continuous access to trained providers.
Alongside Bynum, the study includes contributions from Slim Benloucif and Jonathan Martindale of the U-M Department of Internal Medicine, A. James O’Malley of Dartmouth College, and Matthew A. Davis, Ph.D., of the U-M School of Nursing and U-M Medical School’s Department of Learning Health Sciences.
Bynum and Davis are affiliated with the U-M Institute for Healthcare Policy and Innovation, serving as leaders of the Center to Accelerate Population Research in Alzheimer’s (CAPRA).
This research was funded by the National Institute on Aging of the National Institutes of Health (P01AG019783).
More detailed information about the diagnostic intensity rates and other data for each HRR will be accessible on the CAPRA website and at https://michmed.org/38XeZ.
