A MARTINEZ, HOST:
After turning 60, minor problems with memory and thinking are pretty common. And for about 15% of people, these problems are a sign of a condition called mild cognitive impairment. Yet, as NPR's Jon Hamilton reports, most Americans don't know much about the condition.
JON HAMILTON, BYLINE: Mild cognitive impairment describes a gray zone between normal aging of the brain and dementia. Maria Carrillo, chief science officer of the Alzheimer's Association, says the symptoms can be easy to miss.
MARIA CARRILLO: Mild cognitive impairment is often confused with normal aging because it is very subtle, like forgetting people's names, forgetting, perhaps, that you've said something already, forgetting a story, forgetting words.
HAMILTON: The condition, which affects about 10 million people in the U.S., can also be an early sign of Alzheimer's disease, the leading cause of dementia. Most Americans don't know that, though. A national survey released this week by the Alzheimer's Association found that 82% knew little or nothing about mild cognitive impairment. Carrillo says that's a problem because people need to see a doctor to get a diagnosis and treatment.
CARRILLO: And if more than 4 in 5 Americans know very little, they're certainly not going to do that, which means they're not opening the door to potentially understanding what the underlying cause is.
HAMILTON: Carrillo says a trip to the doctor often reveals that memory and thinking problems aren't mild cognitive impairment at all.
CARRILLO: Maybe somebody was tired. Maybe somebody is not sleeping well. Maybe somebody has depression or is taking some medications that make them a little groggy.
HAMILTON: In other cases, Carrillo says, doctors find problems that are easy to fix.
CARRILLO: There are some actually that can be reversible. If there's a vitamin B12 deficiency, it does actually mimic mild cognitive impairment or even early Alzheimer's dementia. And that can be solved with vitamin B12 injections.
HAMILTON: Even so, just 40% of people surveyed said they would see a doctor right away if they had symptoms of the condition. Carrillo says that's unfortunate because Alzheimer's treatments are most likely to work if they are started long before a patient has dementia, so getting to a specialist is key.
CARRILLO: At a specialty clinic, we absolutely can detect whether mild cognitive impairment is due to Alzheimer's or not.
HAMILTON: Dr. Pierre Tariot directs one of those specialty clinics, the Banner Alzheimer's Institute in Phoenix. The first thing he does is assess whether a patient's memory or thinking problems are interfering with their daily life. That determines whether mild cognitive impairment has become full-on dementia. Tariot says once he has a complete picture of a patient's cognitive problems, he'll order tests.
PIERRE TARIOT: We're rapidly zooming into an era where we can use imaging or blood or spinal fluid tests to establish likely causes of this picture.
HAMILTON: If the tests show sticky plaques or tangled fibers in the brain, Tariot can be pretty sure a patient is in an early stage of Alzheimer's. And he says there are a growing number of treatment options for these patients. One is Aduhelm, a controversial Alzheimer's drug approved last year by the Food and Drug Administration. But Tariot says patients can also opt for a range of clinical trials of experimental Alzheimer's drugs.
TARIOT: They're all scientifically sound, ethically sound, approved by the FDA, done under FDA oversight.
HAMILTON: And Tariot says many more experimental treatments are on the way.
TARIOT: There is a whole wave of other therapies coming forward. So we'll have many more choices than we have now, and that's great news.
HAMILTON: Projections show that the number of Americans with Alzheimer's disease will rise from 6.5 million in 2021 to more than 12 million by 2050.
Jon Hamilton, NPR News.
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