Mild cognitive impairment (MCI), sometimes known as cognitive decline, refers to a small reduction in memory and thinking skills that can occur in older age. This may cause a person to become more forgetful. However, the symptoms are not so severe that a person cannot live independently.

MCI progresses at a faster rate after ages 55–60 years. Doctors base a diagnosis on a person’s medical history, input from family members, an assessment of mental function, a neurological exam, and lab tests.

There is no standardized treatment for MCI. Preventive measures include eating a healthy diet, exercising regularly, and staying socially active.

This article discusses cognitive decline and the age it occurs. It also examines symptoms, risk factors, diagnosis, treatment, and prevention of the condition.

A person in a kitchen who may have mild cognitive impairment (MCI).Share on Pinterest
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Cognitive decline, or MCI, is a slight decrease in memory or the ability to think. Despite the decrease in memory, people with MCI can still live independently and perform their usual daily activities.

The symptoms of MCI are less severe than the symptoms of dementia. They are also less broad. For example, they do not cause personality or mood changes.

The effects of MCI on a person’s memory and thinking ability will likely be noticeable to the person and those close to them. However, the person does not lose the ability to complete most daily tasks and can continue to live on their own.

The common signs or symptoms of MCI include:

  • forgetting about appointments or social events
  • misplacing household items, such as car keys, clothing, or other objects
  • having difficulty finding the right words compared with peers of the same age
  • experiencing movement difficulties

According to the Alzheimer’s Association, other symptoms can include:

  • inability to form certain sounds
  • trouble remembering events, instructions, or conversations
  • problems completing tasks
  • issues with visual perception

However, it is worth noting that these symptoms can also stem from other conditions. Thus, a person should discuss their symptoms with a doctor.

MCI does not have a single cause. Instead, a range of factors can contribute to its development. These include:

  • older age
  • substance misuse
  • long-term alcohol use

Health conditions that may increase the risk of MCI include:

Medications that can raise the risk include:

Some conditions that may mimic or cause similar symptoms to MCI include:

  • infection
  • vitamin or thyroid deficiencies
  • changes in eyesight or hearing

MCI differs from dementia. Dementia is more severe and affects multiple brain functions in addition to memory. It can also change a person’s mood and personality, which MCI cannot.

In contrast, MCI typically only affects memory and is mild in severity. Usually, having MCI does not mean a person cannot live independently.

Does MCI lead to dementia?

According to the Alzheimer’s Association, although many people living with MCI may be in the early stages of Alzheimer’s disease, this is not always the case.

The National Institute on Aging notes that approximately 10–20% of those aged 65 years or older with MCI go on to develop dementia over a period of 1 year. However, in many cases, the symptoms of MCI remain stable or lessen with time.

There is no single test that can diagnose MCI, so a doctor will perform a variety of assessments to make a diagnosis. This may involve:

  • Medical history: This includes telling a doctor about current symptoms, previous conditions, and any history of memory or cognitive problems in the family.
  • Input from a family member or friend: This provides another perspective on how a person’s mental function has changed.
  • Assessment of independent function: This notes any changes from an individual’s typical function.
  • Assessment of mental function: This uses short tests to evaluate memory and thinking skills.
  • Assessment of mood: This can reveal the presence of depression, which is a common condition in older adults.
  • Neurological exam: This tests a person’s:
    • reflexes
    • balance
    • senses
    • coordination
  • Laboratory tests: These may include blood and imaging tests to rule out other conditions.

People living with MCI often first receive a diagnosis when either they or a loved one notices that they are having more difficulty remembering things or processing thoughts. Issues with memory loss may prompt the person to speak with a doctor.

If MCI has a treatable cause, such as a nutrient deficiency, the condition can be reversible. However, there are no approved medications or standardized treatments for MCI that has no treatable cause.

That said, a 2020 review suggests that regular aerobic or resistive exercise may increase cognitive function. The author recommends a minimum of 150 minutes per week of moderate to vigorous exercise. Further studies are necessary to confirm whether this could be a treatment for MCI.

There are several changes people can make to their daily routines to make the symptoms of MCI easier to manage. They include:

  • following a regular routine so that tasks are easier to remember
  • putting commonly used items, such as keys and wallets, in the same place every day
  • setting automatic reminders on a phone or other device
  • using to-do lists, calendars, or other tools
  • getting enough sleep — aiming for 7–8 hours per night
  • eating a nutritious, balanced diet

Keeping the mind active may also help. People can try:

  • learning a new skill
  • doing puzzles
  • volunteering in the community
  • socializing with friends and family

Here are 22 brain exercises that improve memory and cognition.

It is not always possible to prevent MCI, but people can take steps to look after their cognitive abilities more generally. The National Institute on Aging recommends that people:

Take care of physical health

This includes:

  • getting enough sleep
  • quitting smoking
  • limiting the use of alcohol
  • reducing the risk of brain injuries from falls
  • checking with a doctor about side effects from medications that might harm cognition
  • managing chronic health conditions, such as:

Eat a healthy diet

A person should try to focus on eating nutrient-dense foods, such as:

  • fruits
  • vegetables
  • whole grains
  • fish
  • poultry
  • lean meats
  • dairy products

Try to limit:

  • added sugars
  • excessive salt
  • saturated fats

Learn more about diet and brain function.

Get regular exercise

Just as regular exercise may offer a means of treating MCI, it may also provide some protection against it. Exercise helps maintain memory and other cognitive functions.

Learn more about the benefits of aerobic exercise for the brain and body.

Stay mentally and socially active

Keeping the mind active and staying connected to others may benefit the brain, including cognition as well as mental health. People can try:

  • learning new skills or hobbies
  • volunteering
  • visiting family and friends
  • joining local clubs or interest groups
  • participating in group sports or outdoor activities

Manage stress

Chronic stress can have a negative effect on memory. Stress-reducing tips include:

  • using relaxation techniques, such as deep breathing exercises
  • practicing mindfulness or meditation regularly
  • writing in a journal

Learn more about why stress happens and how to reduce it.

A person should speak with a doctor if they notice symptoms of MCI. Family members or friends who notice any signs of cognitive decline in a loved one should consider discussing this with them. Early intervention may help prevent further cognitive decline.

If a person develops MCI, they should speak with a specialist or doctor every 6–12 months. A healthcare professional can help keep track of any changes in memory and thinking skills.

The outlook for MCI in many cases is fairly positive. In situations where there is a treatable or temporary cause, a person may be able to make a full recovery.

In other cases, people with MCI may experience a long-term change in memory, but they can often continue to live life independently. This depends on them being able to complete daily tasks around the home and the condition not progressing to Alzheimer’s or another degenerative disease.

Mild cognitive impairment (MCI) is a mild loss of memory or cognitive skills. A person with MCI may notice that they have become forgetful or have more trouble coming up with words than their peers. A number of risk factors can contribute, such as older age and certain health conditions.

While the condition may start earlier, it becomes more common past ages 55–60 years. There is no treatment, but people may find that certain lifestyle changes help them manage the symptoms.