Mild Cognitive Impairment: What You Need to Know

Likewise, sleep apnea — a disorder in which breathing stops and starts as you doze, preventing your brain from getting enough oxygen — can also lead to cognitive slippage, resulting in memory loss.

“Some people [with MCI] will be in the early stages of a neurodegenerative process, such as Alzheimer’s disease,” says Munro Cullum, a clinical neuropsychologist who specializes in cognitive disorders at UT Southwestern’s O’Donnell Brain Institute. Studies assessing biomarkers for Alzheimer’s disease with PET scans have reported that about half of people who experience MCI have Alzheimer’s-related brain changes.

“Others may experience cognitive decline or memory loss due to a variety of conditions such as vascular factors, metabolic disturbances or other medical conditions that can affect the brain," says Cullum.

When to see a specialist

When a change in memory or cognition becomes noticeable to you, or to friends and family, it’s time to see your primary care physician, who may refer you to a neurologist. A neurologist will use biomarker tests, such as amyloid PET brain scan, cerebrospinal fluid test and newer blood tests, to detect signs of amyloid buildup, a precursor to Alzheimer’s, says Gandy, adding that a test for a variant of the apolipoprotein E gene (APOE-e4) isn’t required for diagnosis but can determine genetic risk. An MRI may be used to rule out other causes.

A neuropsychologist may be enlisted to administer cognitive screening tests, such as the Short Test of Mental Status or the Montreal Cognitive Assessment. Those tests assess memory and measure changes in problem-solving, comprehension, reasoning and other cognitive skills.

“What we try to do with a neuropsychological evaluation is distinguish normal aging from pathological aging,” Cullum says. “Our tests are quite sensitive to MCI and early-stage dementia.” (See Healthy Aging vs. MCI vs. Dementia.)

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Is MCI reversible?

The fast answer: It depends on the underlying cause.

If testing determines that a treatable medical condition, such as a urinary tract infection, is causing the MCI, then treatment for that condition may reverse the MCI. In fact, research suggests that 20 percent of people with MCI, on average, regain normal cognition (though they are at higher risk of progression back to MCI or dementia than those who were never diagnosed with MCI).

For example, a CPAP machine can ease sleep apnea. Depression can be treated with medication, therapy or a combination of both. Dietary changes, supplements or injections can reverse a vitamin B12 deficiency.

“I have patients who say, ‘I can’t remember a thing, I’m disoriented, I’m confused,’ and it turns out they have a vitamin B12 deficiency, a urinary tract infection and they’re depressed — all these different factors,” says Tamar Gefen, a neuropsychologist at Northwestern Memorial Hospital. “You treat the UTI, the vitamin deficiency and the depressive symptoms and [the cognitive issues] resolve.”

That MCI may be caused by something treatable and reversible “is so important,” she adds. “There are people walking around thinking they have something like Alzheimer’s disease, but it’s not.”

There is a subset of people with MCI, however, whose condition is unlikely to improve without treatment.

“Every year they’re getting worse, and eventually they progress to dementia,” Kremen says. “At the beginning, it may not be easy to tease those people apart. Obviously, the goal is to be able to figure out who those people are, as early as possible, to begin to initiate proper treatment.” Around 1 in 3 people with MCI due to Alzheimer’s pathology go on to develop Alzheimer’s within five years without intervention, Aurora says.

Although there are no medications approved by the U.S. Food and Drug Administration specifically for MCI, two therapies for early-stage Alzheimer’s disease are often prescribed. Lecanemab (Leqembi) and donanemab (Kisunla) can’t reverse cognitive decline, but they’ve shown promise in slowing the progression to Alzheimer’s. They work by removing the problematic amyloid proteins from the brain.

Is MCI preventable?

Research shows that lifestyle changes also go a long way toward preventing or slowing the progression of cognitive decline, and that applies to MCI — regardless of the underlying cause.

In a small study of people with MCI or Alzheimer’s disease, those following an intensive lifestyle intervention showed improvements in cognition.

And in a recent study published in JAMA, participants who had risk factors for cognitive decline who followed a structured regimen that included regular moderate- to high-intensity bouts of physical exercise, adherence to the MIND diet, cognitive challenge and social engagement, and cardiovascular health monitoring showed greater improvement in cognition after two years, as compared with those who followed a lower-intensity, less structured regimen.

“These strategies may enhance resilience to cognitive decline due to any cause by sustaining synaptic health,” or the health of the connections among brain cells, explains Gandy, who wasn’t involved in the study.

How can you know if MCI is progressing to dementia?

The mishaps and slipups start happening with greater frequency.

“One key difference between mild cognitive impairment and dementia involves the degree at which the cognitive impairment affects a person’s ability to complete activities of daily living, such as taking medications, driving, managing finances, dressing and bathing,” says Dr. Chad Yucus, cognitive and behavioral neurologist at Endeavor Health in the Chicago area.

“In MCI, memory difficulty may be present but does not prevent a person from being independent,” he adds. “In dementia, a person is unable to complete activities of daily living due to the severity of the memory problem, or other cognitive problems such as language, executive or visual spatial problems.”