The signs of MCI vary from person to person. You may begin to notice any of the following:

  • trouble remembering details from recent conversations
  • relying on a notebook or printed calendar to keep track of your schedule
  • difficulty remembering items you wanted while shopping
  • struggling to keep organized or stay focused
  • difficulty keeping up with bills and finances or staying on top of day-to-day tasks at home
  • uncertainty about your ability to drive to a familiar location, like a friend’s house, and resorting to your GPS

Your loved ones may even notice these things and come to you with concerns before you’ve realized anything is off.

But just because you sometimes forget your reading glasses are on top of your head or have trouble concentrating after a poor night’s sleep, it doesn’t necessarily mean you have MCI.

Sometimes, MCI represents the earliest stages of pathologic changes in the brain.

For example, in the earliest stages of Alzheimer’s, proteins build up in memory structures. In early stages of vascular disease in the brain, plaque builds up in the brain’s smallest blood vessels.

Other times, MCI may be due to reversible causes. These include:

  • endocrine changes
  • vitamin deficiencies
  • untreated sleep apnea
  • other medical conditions

Certain medications can also cause clouded thinking.

The biggest risk factor for MCI is one you can’t do much about — your age. But other important risk factors are modifiable, such as:

  • physical inactivity
  • obesity
  • tobacco use
  • high blood pressure
  • high cholesterol
  • diabetes

Specific symptoms can sometimes provide clues about the cause of your cognitive impairment.

For instance, MCI that primarily affects your ability to focus, multitask, and pay close attention may be more likely to be due to sleep problems, thyroid difficulties, sedating medications, or vascular changes.

But MCI that impacts your short-term memory may be more likely to represent the earliest stages of Alzheimer’s proteins in the brain.

A person has progressed from MCI to dementia when their symptoms affect their ability to manage their day-to-day activities independently.

For example, someone with MCI may double-check to make sure they took their morning medications or use a pill box to make it easier to keep track of them.

But if the person and their family decided it’d be better for a family member to keep track of the medications instead — maybe because they’d missed doses of important medications or accidentally taken them twice — this may be an early sign of dementia.

Our brains change in significant ways as we get older.

It’s not unusual to have a hard time calling up the name of an acquaintance you run into on the street or to find yourself standing in your basement trying to remember what you’d gone down there to get.

These kinds of changes are common in normal aging.

However, you should get evaluated for MCI if you notice a consistent pattern of difficulty with:

  • memory
  • organization
  • finding your way
  • thinking of words

If a family member raises concerns, you may also want to see a doctor.

MCI is a clinical diagnosis. Your doctor will take a careful history to learn about your concerns and ask detailed questions about any other symptoms you’re experiencing.

Bringing a family member to your visit can give your doctor an outside perspective on how you’re doing.

Your doctor may do a brief cognitive assessment to determine whether your performance is lower than expected for your age and level of education.

After an MCI diagnosis, your doctor may order blood tests to check for endocrine changes or vitamin deficiencies that may be causing your symptoms.

They may also order a brain scan to look for vascular changes or volume loss in your brain. These tests can help clarify the cause of your MCI.

If your loved one has been diagnosed with MCI, encourage them to exercise and eat well. Performing moderate-intensity cardiovascular exercise and following a heart-healthy diet, such as the Mediterranean diet, can provide significant benefits for people with MCI.

Staying cognitively and socially active is also great for brain health. This includes activities that are both enjoyable and challenging, like:

  • learning a new language
  • participating in a choir or social dance group
  • joining a book club
  • taking an active role volunteering for a cause you believe in

Even if you’re not able to leave your home, you can still find activities like this. You might download an app for language learning or find a book club with virtual meetings.

People with MCI are at a higher risk for progression to dementia. Most estimates are that someone with MCI has about a 10 to 15 percent risk of transitioning to dementia each year.

Severe dementia can make people more vulnerable to infections, which can be serious if left untreated.

It’s also important to find and treat any medical problems that may be causing or contributing to your symptoms. These can be dangerous if untreated.

For instance, if your MCI is caused by undiagnosed hyperthyroidism, that can lead to complications like:

  • heart problems
  • unintentional weight loss
  • bowel symptoms
  • eye problems

If your MCI is caused by severe untreated sleep apnea, that can put you at higher risk for:

  • stroke
  • heart attack
  • abnormal heart rhythm

It can also worsen chronic conditions like high blood pressure.

Your doctor can help you determine which treatment option is best for you.

Carolyn A. Fredericks, MD, is a Yale Medicine neurologist who specializes in diagnosing and treating patients with a variety of cognitive and behavioral conditions, including Alzheimer’s disease, frontotemporal disease, and other common causes of mild cognitive impairment and dementia. She also researches and treats less common forms of Alzheimer’s disease, such as posterior cortical atrophy and logopenic aphasia. Fredericks is an assistant professor of neurology at Yale School of Medicine in New Haven, Connecticut.