Approximately 15 to 20 percent of people over the age of 65 have mild cognitive impairment (MCI). People with MCI, especially MCI involving memory problems, are more likely to develop Alzheimer’s disease or other dementias than people who do not have this condition. However, MCI doesn’t always lead to dementia, as many folks fear and believe.

In fact, MCI is not always permanent.

“It depends on the underlying cause,” says Dr. Joel Salinas, a neurologist at Harvard-affiliated Massachusetts General Hospital. MCI is not dementia but it’s not normal thinking either. The most common causes stem from disease or treatments for disease, including:

• degenerative brain disease, such as Alzheimer’s disease
• stroke or other vascular disease
• traumatic brain injury
• a medication side effect
• an underlying health problem such as sleep deprivation, depression or anxiety

There are two kinds of MCI, according to Harvard Health Publishing. Although the symptoms are not severe in either type, both can be upsetting and disruptive.

Amnestic MCI is memory-specific and marked by signs like forgetting conversations and misplacing items. Non-amnestic MCI involves changes in other types of brain activity regardless of whether or not you have memory loss. For example, you may lose your train of thought during a conversation or have a hard time focusing on a certain task at hand like paying your bills.

The American Academy of Neurology (AAN) recently published new guidelines for the treatment of MCI and notes that about 15% of MCI cases progress into full blown dementia. Dr. Salinas adds that when the cause is a neurodegenerative disease, the numbers of those who progress into dementia will be higher. What’s unclear is how long this progression takes.

“If the cause is Alzheimer’s disease, it may take two to five years,” he says. “But I’ve seen patients stay in the MCI stage for many years, even when we presume it was a neurodegenerative disease.”

Dr. Salinas says that MCI can often be reversed if a general health condition such as sleep deprivation is causing the decline. By treating the underlying cause, cognition dramatically improves.

Because there are no pills to slow the worsening of memory problems, treatment can be challenging. However, the AAN has found encouraging evidence linking exercise with better memory in people with MCI.

Exercising can offer both mental and social stimulation while improving blood flow to the brain. This increased blood flow may also release molecules that can repair brain cells and make connections between them and so the new guidelines recommend exercising at least twice a week. Cognitive tasks like operating a computer or playing video games can also sharpen your brain’s response time and improve attention span.

In 2015, the famous FINGER trial, a randomized controlled study, found less cognitive decline over two years in older adults who maintain a combination of habits, such as eating a healthy diet, exercising regularly and taking part in social events.

Dr. Salinas advises people with MCI to emulate the healthy habits of older adults studied in the FINGER trial along with adding mentally stimulating activities like a taking up new hobby or learning a new language and also talking to their doctors about the medications they are taking to help stave off dementia.

There are no guarantees, but the evidence does suggest that these steps may delay or even prevent progression to dementia.

“The people who spend the most time cognitively stable are often the ones who stick to healthy lifestyle recommendations,” he says.