Most people with dementia in the US are unaware of their condition. A population-based study in Texas has now found that four out of five people with probable dementia have not received a formal diagnosis and are not being treated for cognitive decline.
That's not for a lack of healthcare, either. In the new study, less than 7 percent of participants with probable dementia had no primary care provider, and there was no link between a lack of primary care and a lack of diagnosis.
In other words, most people over the age of 65 with cognitive decline were routinely seeing their doctor, but they were not receiving a diagnosis.
"The physician may not be diagnosing the patient or may be withholding the diagnosis of dementia," suggests public health scientist Josh Martins-Caulfield from the University of Michigan.
"In practice, physicians often hesitate to diagnose dementia, citing reasons such as insufficient time with individual patients to conduct the screening process or not having dementia-specific training. The discomfort of providing the diagnosis may also lead them to wait for patients or family members to raise concerns about memory issues rather than initiating discussions proactively."
The study focused on 652 older adults in Nueces County who were under the close care of another, usually a child or spouse. Of this group, 322 people – with a median age of 76 – were considered to have "probable dementia" by researchers.
When these 322 patients and their caregivers were surveyed, up to 84 percent said they had not received a formal diagnosis from their doctor.
The authors also noticed significant differences between ethnic groups. Among Mexican American participants with probable dementia, for instance, nearly 85 percent had not been told by a doctor they had dementia.
Non-Hispanic White participants with probable dementia, meanwhile, had received a diagnosis in 65 percent of cases.
Routine access to primary care could not explain the "substantial ethnic disparity", but in the past, the Alzheimer's Association has found that a third of Hispanic and Latino Americans experience discrimination when seeking healthcare. That's compared to just 9 percent of non-Hispanic White Americans.
The recent data comes from just one county in Texas, so it is not necessarily representative of the entire nation. In 2023, however, researchers from the University of Southern California used Medicare records to predict that of the 8 million Americans who are currently experiencing mild cognitive impairment, more than 90 percent don't know it.
Today, most available medications for Alzheimer's patients can only help manage their symptoms. Just a recent, rare few have any impact on disease progression. If that changes down the road, however, healthcare providers around the world will have their work cut out for them.
In 2021, researchers at McGill University in Canada warned that if new treatments for dementia really did prove safe and useful in the future, it could result in a 'tsunami of demand' for diagnoses. The latest findings suggest many healthcare systems may be wholly unprepared for the onslaught.
Last year, the US Food and Drug Administration (FDA) approved a drug designed to treat the early symptoms of Alzheimer's disease that shows encouraging initial results.
The best outcomes, however, tend to be when these drugs are administered in the early stages of the disease. A recent study of more than 200,000 clinicians in the US estimated 99.9 percent under-diagnosed mild cognitive impairment in their patients.
A blood test of some sort would certainly be helpful.
The study was published in the Journal of General Internal Medicine.