United States: In the United States, an estimated 7 million individuals grapple with Alzheimer’s disease and related dementias. However, the number of those who have been formally diagnosed is considerably lower. A recent study suggests that the likelihood of receiving a formal diagnosis may hinge significantly on one’s geographic location.
Scholars from the University of Michigan and Dartmouth College have unearthed substantial discrepancies in diagnosis rates across the nation, disparities that cannot merely be attributed to known dementia risk factors, such as the prevalence of hypertension, obesity, or diabetes in a given area, according to NPR News.
The underlying reasons for these variations remain enigmatic. Still, researchers hypothesize that factors such as societal stigma and access to primary care or neurological specialists may play a pivotal role in determining whether an individual receives a formal diagnosis.
“There are many narratives about the difficulties of obtaining a diagnosis, and these challenges might be more pronounced in certain regions. It’s not just your imagination—it genuinely varies from place to place,” remarked Julie Bynum, the lead author of the study and a geriatrician at the University of Michigan Medical School.
These regional differences could have profound implications. A formal Alzheimer’s diagnosis is crucial as it opens the door to treatments that may decelerate the cognitive decline associated with the disease. Moreover, without a formal diagnosis, patients may be ineligible for clinical trials or insurance coverage for specific medications. Even when treatment options are limited, a diagnosis is invaluable for planning patient care, as reported by NPR News.
The study, published recently in the journal Alzheimer’s & Dementia, sought to answer two critical questions: What proportion of older adults are being diagnosed with dementia across various US communities? And how does this observed percentage compare with what would be expected?
To address these questions, researchers leveraged Medicare and demographic data to create two maps. The first map depicted the percentage of individuals receiving a formal diagnosis in each hospital referral region (HRR), which segments the nation into 306 areas based on where people typically seek medical treatment. The second map estimated the percentage of each HRR, accounting for health risk factors and racial demographics, according to NPR News.
The findings revealed stark contrasts between the two maps, with regions like the Great Plains and Southwest showing lower-than-expected diagnosis rates. For instance, a resident of Wichita Falls, Texas, might be twice as likely to receive a diagnosis compared to someone living in Minot, North Dakota.
“Even among individuals who are all 80 years old, where you live can double your likelihood of receiving a diagnosis,” Bynum noted.
It’s challenging to definitively determine whether an area is under-diagnosing, as the researchers compared each HRR to the national diagnosis average rather than the actual number of cases in each community, she added.
Nevertheless, the findings illuminate the fact that dementia diagnosis rates are more prevalent in some regions than others—not solely due to individual risk factors but also due to disparities in access to healthcare resources and educational outreach regarding the disease.
Erin Abner, an epidemiologist at the University of Kentucky who was not involved in the study, expressed that the results were not surprising, citing numerous barriers to diagnosis.
“Geographic location exerts a powerful influence on our cognitive health,” she said. “In many parts of the country, it is exceedingly difficult for adults to access behavioral, neurological specialist care—often, the waiting lists extend for months or even years.”
For some individuals, language and cultural differences may also impede access to care, as per NPR News.
The process of diagnosing Alzheimer’s can be protracted, involving cognitive and neuropsychological assessments, as well as tests detecting amyloid plaques in the brain. Bynum hopes the study’s findings will shine a light on the role that healthcare systems play in diagnosis rates and in identifying individuals who may be living with undiagnosed dementia.
“The role of our healthcare and public health systems in informing and educating populations is crucial,” Bynum said. “And in many ways, this is something we can address.”