Millions of older adults may have undiagnosed dementia, study says. Why that matters

A survey of Americans at least 65 years old who show signs of cognitive decline similar to those of dementia found that only 10% have received a formal diagnosis of the condition, with disparities seen across race, gender and education level.

This means many more older adults are living with undiagnosed dementia than previously thought, which could lead to major health consequences, particularly during the COVID-19 pandemic.

Studies show people with dementia face higher risks for hospitalization and death from coronavirus infection; the disease also affects some people’s brains in ways that could increase adults’ chances of developing dementia later in life.

Researchers place some blame on a lack of dementia screening during routine medical visits for older adults, allowing millions of cases to slide under the radar. It’s an issue that telemedicine appointments, which gained popularity during the pandemic when physical distancing was a must, can help tackle.

“We recommend that health care providers screen for low cognitive functioning during routine health assessments when possible,” study co-author Ryan McGrath, an assistant professor at North Dakota State University, said in a statement. “A telemedicine option may reduce clinic time and expand reach.”

The team extracted data from a University of Michigan Health and Retirement Study “to develop a nationally representative sample of roughly 6 million Americans age 65 or older,” the statement said. Information was collected via telephone interviews and self-reports of dementia diagnoses.

While 91% of people with signs of cognitive impairment did not report a formal diagnosis of dementia, the researchers said some of the participants may have forgotten about it or remained unaware.

When family members responded on behalf of their loved ones, the percentage of people missing a diagnosis dropped to 75%, “which is still very significant,” according to study co-author Sheria Robinson-Lane, an assistant professor at the UM School of Nursing.

Undiagnosed dementia was also more prevalent among males, those without high school diplomas, and Black people, who are most affected by the condition in the U.S. — 13.8% of those who are 65 or older have Alzheimer’s or related dementias, according to a 2018 Centers for Disease Control and Prevention study. They are followed by Hispanic people (12.2%), white people (10.3%), American Indian and Alaska Native people (9.1%), and Asian and Pacific Islanders (8.4%).

Dementia is caused by abnormal changes in the brain that lead to cognitive decline. It’s an umbrella term for several medical conditions such as Alzheimer’s and Parkinson’s, and its prevalence is expected to grow among older adults. Current estimates show about 6 million Americans have Alzheimer’s.

The CDC study found that the burden of Alzheimer’s disease and other dementias will double by 2060 to include 13.9 million people largely because of population growth.

“(The discrepancy) was higher than I was expecting,” Robinson-Lane said of her new study published in May. “Now more than ever, these routine screenings and assessments are really critical. I think it’s particularly important to have some baseline information available to providers of patients over 65.”