Physicians Are Dramatically Underdiagnosing Early Cognitive Decline, a Precursor to Alzheimer’s

Changes to the brain are natural as we age, which often makes it difficult to spot more aberrant signs of cognitive decline in older adults. Neurodegenerative diseases like Alzheimer’s and Parkinson’s, as well as other common disorders that can affect the mind, often first arise as clusters of symptoms that qualify as mild cognitive impairment, or MCI. In many cases, catching disease at this stage can massively increase the success of treatments—which is why researchers at the University of Southern California are so concerned by their recent analysis suggesting that over 90% of Americans with MCI remain undiagnosed. What’s more, of the more than 200,000 primary care physicians surveyed, all of whom see patients 65 and older, 99% are underdiagnosing MCI.

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“We expected it to be bad, but we didn't really expect it to be that bad,” says Soeren Mattke, director of the Brain Health Observatory at USC Dornsife’s Center for Economic and Social Research and a lead author on the team’s most recent paper. There’s a clear reason to address this oversight now. The first Alzheimer’s drug to be approved by the U.S. Food and Drug Administration, which became available this summer, can slow down the disease’s progress, but only if used in the early stages of the condition. About one-third of people diagnosed with MCI will develop dementia due to Alzheimer’s within five years. Mattke says that urgent need motivated the research, published Oct. 24 in the The Journal of Prevention of Alzheimer’s Disease. “We have to find these patients early and get them into treatment,” he says.

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Getting an MCI diagnosis currently requires a lot of unlikely pieces to fall into place, explains Mattke. First, someone has to notice cognitive changes, which is difficult, given that MCI presents itself with inconsistent symptoms. In some people, it could manifest as unusual memory lapses, in others issues with orientation, and in others still as struggles with information processing or decision making. For physicians, this makes it hard to tell families and patients what to look out for, and for patients, it makes symptoms easier to hide. Neurological decline can be a major source of shame for older adults, who may go out of their way to compensate for symptoms in order to avoid detection by family members and clinical evaluation. This is even more true for people with MCI, whose mental changes fall outside the standard expected for their age group. Because MCI is, by definition, mild, it’s also unlikely to be noticed by someone who doesn’t know the patient well or doesn’t spend much time with them, including their primary care physician. 

Good tests for MCI do exist, and if a patient arrives with concerns about mental impairment, a physician might administer the simplest one, which takes about 15 minutes to conduct and score. While 15 minutes might not seem like a lot, it’s just a few shy of the average 19 minutes that primary care physicians spend with their patients. A test is a great option if it’s what a patient came in for, says Mattke, but it’s impossible for the large number of patients who come in for a check-up or other concern and only mention a family member’s worries about their cognition offhandedly at the end of a visit—a common experience for doctors treating older populations. “Then of course, that's tough for the primary care doctor, because if you start that conversation that takes about half an hour and that upsets your entire day,” he says.

Shorter tests, or tests that can be administered in the waiting room, are clear goals for experts. “These tests are all very new,” says Mattke.

Mattke says he hopes to do additional research that would allow him to put together risk-scoring algorithms that physicians could use to identify people for testing, similar to those that exist to spot older adults at risk for cardiac events. This would be particularly beneficial for improving detection in socioeconomically disadvantaged groups, where risk factors like poor blood pressure and cholesterol—both associated with dementia as well as cardiovascular events—are higher.

“Brain cells don’t grow back,” says Mattke. If you feel like you or a loved one might be showing signs of MCI, “don’t let a physician brush it off.”