What is mild cognitive impairment (MCI)?

Mild cognitive impairment or MCI, occurs when an individual acknowledges that their memory and thinking skills have shown some signs of decline. The individual’s family and friends will most likely notice the same.

Your doctor or health care team might also use the term, “Mild Neurocognitive Disorder”. The essence of MCI is that a person’s cognitive functioning is worse than expected but not bad enough to be considered as dementia.

How common is mild cognitive impairment?

Estimates vary, but roughly 10-20% of people over age 65 have MCI, with the risk increasing as someone gets older.

People with mild cognitive impairment are at a higher risk of developing dementia, with 10-15% of people with mild cognitive impairment developing dementia each year. 

What causes MCI?

MCI can be caused by all of the same things that cause dementia, such as Alzheimer’s disease. It can often be hard to find the cause of MCI, but it’s important for the health care team to do a full assessment to try to manage any underlying causes. Some potential causes include:

• Depression is a very important and common cause of MCI.  People that have MCI as a result of their depression can show significant improvements in cognitive function when their depression is treated. (You can learn more about depression in older adults on our site.)
• Medication side effects, alcohol use, low thyroid function or vitamin B12 deficiency are other potential causes of MCI that can also be treated. 
• Toxic proteins can cause several types of dementia like Alzheimer’s disease. If toxic proteins are the most likely cause of the memory and thinking problems in mild cognitive impairment, it’s more likely that the cognitive decline would be expected to continue. 
• Blood vessel damage due to a stroke or diabetes can lead to MCI. There may be additional treatments recommended to help protect against further damage.

Who is at risk for MCI?

The risk of developing MCI increases as someone gets older. Conditions such as diabetes, depression, and stroke may also increase a person’s risk for MCI. 

Research suggests that genetic factors may play a role in who will develop MCI, as they do in Alzheimer’s and related dementias.

What are the signs and symptoms of MCI?

The cognitive changes that people with MCI show are more obvious on testing than those with normal aging. Everyday tasks or functions might take more effort for the person with MCI, or they might need to find ways to make up for their cognitive changes; like writing down reminders to make up for a worsening of their memory.

People with MCI tend to be troubled by the inability to complete tasks or function in their day-to-day lives the way they used to. People with normal age-related changes are not impacted to the same degree as those with MCI. 

In MCI, everyday functioning is less impaired than dementia. People with MCI can still function independently with all of their day-to-day functions. In contrast, people with dementia have cognitive decline to a point where it significantly interferes with their independence in everyday activities. 

MCI-related memory problems may include: 

• Losing things often
• Forgetting to go to events and appointments
• Having more trouble coming up with words than other people of the same age

Signs that it might be time to talk to a doctor include:

• Asking the same questions over and over again
• Getting lost in places a person knows well
• Having trouble following recipes or directions
• Becoming more confused about time, people, and places
• Not taking care of oneself —eating poorly, not bathing, or behaving unsafely

Many people with MCI also experience emotional symptoms such as:

• depression
• anxiety
• increased irritability/anger or
• a lack of interest (apathy).

Differences between normal aging, MCI, and dementia

Have a look at the table below to compare and contrast some of the changes that may occur with age vs. those associated with MCI or dementia.

How is MCI assessed and diagnosed?

MCI is assessed and diagnosed by a health care provider; usually a family physician or specialist physician like a geriatrician or neurologist. Most often, a person will go to their doctor with complaints of memory and thinking problems; sometimes families are the first to notice changes and may encourage their loved one to get an assessment. 

There are a few different aspects to a comprehensive assessment:

• History and physical exam – The doctor or another member of the healthcare team will typically take a detailed history of the problem from both the person and a close friend or family member, and also conduct a physical exam.

• The doctor will also ask about any medications and over-the-counter drugs that the person is taking, as well as asking about alcohol and other substance use. (This is because an important side effect of some medications can be cognitive impairment; which can also happen with chronic alcohol or drug misuse.)

• Cognitive tests – The two most common tests used to screen for cognitive problems are the Montreal Cognitive Assessment or MoCA for short, and the Mini-Mental State Examination (or MMSE). Both test memory, attention, complicated thinking, visual and spatial skills, and language. The doctor can tell if there are problems based on how people score, taking into consideration other factors such as the person’s age, English as a second language (ESL) status, or level of education.

• Other tests – To rule out other causes, the doctor will often send a person for blood work and may order pictures of the brain using either a CT Scan or an MRI to make sure there is no obvious damage to the brain. An MRI (magnetic resonance imaging) is a detailed picture of the structures of the brain. Doctors can see shrinkage in certain regions of the brain. This shrinkage, or decreasing brain volume, is called atrophy. If certain areas of the brain have a greater degree of shrinkage than others, doctors can say that there is a higher risk of progression to dementia. Imaging like CT and MRI can also help to detect if there has been blood vessel damage to the brain. While not all people with MCI will require brain imaging like a CT scan or an MRI, in some cases it may be useful. In addition to being useful to assess causes of cognitive impairment, these tests may also be useful in the future, so that if there are new cognitive changes at some point, tests can be repeated and the results compared.

Assessing previous skills 

It’s important to keep in mind each person’s background and previous cognitive strengths when assessing MCI. If somebody was previously an investment banker, and now they have difficulties completing their taxes, that’s a particularly worrisome sign given their previous skills and experience. They may only have MCI now, but they should be monitored for worsening of their cognitive problems. 

Further testing 

While not routinely requested, more detailed cognitive testing other than the MoCA and MMSE can be performed by a neuropsychologist. If these more detailed tests are abnormal, people are at a higher risk of progressing to dementia.

Levels of toxic proteins can sometimes be measured in the fluid that surrounds the brain by gaining a sample of fluid from a spinal tap (or lumbar puncture). In research studies, people have used these levels of proteins to predict progression from MCI to dementia, but these are currently not used outside of research studies in Canada at this time.

There is an evolving area of interest looking for ‘biomarkers’ (like toxic proteins), which are biological molecules found in blood, other body fluids, or tissues that could be a sign of disease. But this is still at a research stage for conditions like MCI and dementia, and not measured as a part of a typical assessment.

What else could it be if not MCI? 

Normal part of the aging process

As we age, some of our cognitive abilities gradually decline: 

• We can’t remember quite as much when learning new information.
• We don’t process things quite as fast.
• Learning more complicated tasks becomes more difficult.

Beginning stages of dementia

Does MCI lead to dementia?

People with MCI are at a greater risk of developing Alzheimer’s disease or a related dementia. Estimates vary as to how many people who have MCI will develop dementia. Roughly one to two out of 10 people age 65 or older with MCI are estimated to develop dementia over a one-year period. However, in many cases, the symptoms of MCI stay the same or even improve.

There is a chance that the severity of the cognitive impairments and problems with independent functioning will progress to dementia.

Some people with MCI will improve and regain their previous cognitive function, some people will remain the same for many years, and some people will progress to have dementia. It is estimated that people with MCI have about a 5-10% increased chance of progressing to dementia per year. Generally, the severity of memory, thinking, and function problems predicts if and how the disease will progress; but it also depends on the underlying cause of the MCI.

Have a look at the table below to compare and contrast MCI and dementia.

No one specific test is used to diagnose MCI. After doing the comprehensive assessment, including history, physical exam, cognitive screening, and investigations to rule out other potential causes of cognitive impairment, the doctor will be able to give you the diagnosis of MCI.

Typically the diagnosis is based on the presence of these criteria:

1. Problems with memory or other cognitive (thinking) functions.
2. A change from your previous cognitive function.
3. Day-to-day function, abilities, and activities have been affected, but not too much – i.e. you are still able to live your life more-or-less as usual despite the cognitive changes.
4. Formal cognitive screening tests like the MoCA or MMSE show some level of impairment, but not too much.
5. The problems aren’t severe enough to be diagnosed as dementia.

The American Psychiatric Association’s DSM-5-TR (the standardized diagnostic manual used in North America) defines Mild Neurocognitive Disorder (their new terminology for MCI) with very similar criteria:

1. Evidence of what they call ‘modest cognitive decline’ from previous in one or more cognitive functions, based on concerns from the patient, a knowledgeable informant, or the clinician; as well as evidence of impairment, preferably from one of those standardized screening tools like the MoCA or other objective testing or assessment.
2. The cognitive deficits don’t interfere with being able to independently do everyday activities, even if they might be a bit harder to do than before.
3. The changes in cognition don’t occur while the person is experiencing a delirium (an acute confusional state usually due to a serious medical condition).
4. The changes aren’t better explained by another disorder, such as major depressive disorder.

If possible, the doctor might try to determine a ‘possible’ or ‘probable’ cause for the Mild Neurocognitive Disorder/MCI.

What are the causes of MCI and their treatments?

Treatments for mild cognitive impairment depend on the underlying cause of MCI. 

• Depression or B12 deficiency – therapies can help improve cognition. Learn more about the treatment of major depressive disorder here.
• Medication side effects or alcohol – there are changes that can be made which might also help thinking and memory. 
  • Several medication classes are known to potentially affect memory and thinking, so your doctor may talk to you about some of these specific drugs if you are having the symptoms of MCI and on these types of medications:
    • Strong pain killers in the opioid family (such as morphine, codeine, or hydromorphone)
    • Some antihistamines
    • Drugs with anticholinergic side effects – there are quite a lot of medicines with anticholinergic effects, such as many types of psychiatric medications as well as drugs used to help manage bladder symptoms and over-the-counter sleep aids
    • Anti-anxiety or sedatives like benzodiazepines.
• Toxic proteins –  there is currently no targeted therapy available in Canada to reverse the underlying damage to the brain or improve cognitive impairment.  
• Blood vessel damage – there is no therapy to reverse the cognitive impairment, but maintaining blood vessel health through management of blood pressure, cholesterol and diabetes can help to prevent further decline.
• Sleep apnea – this is an important and sometimes under-recognized condition that can impact on the quality of your sleep as well as oxygen levels to your brain, which can both impact your thinking and cognitive function. There are specific treatments that can improve the cognitive symptoms.

Are there any medication treatments for MCI?

At this time, there are no specific medicines that are approved for the treatment of MCI. Medicines that are used in the management of Alzheimer’s disease known as ‘cognitive enhancers’ (cholinesterase inhibitors) aren’t usually recommended for the treatment of MCI. So far studies haven’t shown that these medicines reduce the risk of MCI progressing to dementia, and they frequently have side effects.

Tips for dealing with forgetfulness

People with some forgetfulness from MCI can use a variety of techniques that may help them stay healthy and deal with changes in their memory and mental skills. Here are some tips:

• Learn a new skill.
• Follow a daily routine.
• Plan tasks, make to-do lists, and use memory tools such as calendars and notes.
• Put your wallet or purse, keys, phone, and glasses in the same place each day.
• Stay involved in activities that can help both the mind and body.
• Volunteer in your community, at a school, or at your place of worship.
• Spend time with friends and family.
• Get enough sleep, generally seven to eight hours each night.
• Exercise and eat well.
• Prevent or control high blood pressure 
• Don’t drink a lot of alcohol.
• Get help if you feel depressed for weeks at a time.

What are some other things I can do to help manage MCI?

• Visit an occupational therapist – to help you come up with coping strategies

• Keep a journal for appointments, conversations and events
• Use smartphones for reminders or alerts 
• Use pre-filled medication tools – such as blister packs or dossettes – so you don’t forget to take medications, or accidentally take too much medication.
• Avoid stressful situations
• Try not to do too many tasks at once
• Lifestyle changes – Higher alcohol consumption and smoking have both been shown to increase the risk of developing dementia.

Learn more about things you can do to promote brain health.

What type of follow-up can I expect?

If you have MCI, visit your health care provider every six to 12 months to track changes in memory and other thinking skills over time.

When should I get better? Why might I be getting worse?

Although the cognitive problems may not improve or worsen, people with MCI can take steps to limit their impact, as outlined above under Treatment. Because there are likely a range of different causes of MCI, it’s difficult to predict who will have improvements, who’s MCI remains stable, and who will get worse. If the MCI is due to Alzheimer’s disease or one of the other progressive causes of dementia, then the MCI will eventually worsen. If you have another medical illness and that condition is not well-controlled, that may also impact your MCI. Similarly, some medication side effects or substances like alcohol could also worsen your MCI.

How can I prevent MCI? 

While it may not be possible to prevent MCI in all cases, research shows it is possible to reduce your risk of getting MCI or dementia through several key lifestyle factors. Some of the key factors include:

1. a healthy diet
2. regular physical activity and exercise
3. cognitive and social activity
4. not smoking or drinking too much alcohol
5. managing blood vessel health

General brain health may be improved with the right combination of diet, exercise, social activity, and managing blood vessel health (such as blood pressure and blood cholesterol control). Diabetes management and cognitive training may also be somewhat helpful. The more of these lifestyle behaviours that you can do, the better.

Please see the e-learning lesson on Promoting Brain Health for further information.

What should I ask my healthcare provider?

Talk with your doctor or nurse practitioner to determine whether memory and other cognitive problems, such as the ability to clearly think and learn, are normal and what may be causing them.

Be specific about the changes you’ve noticed. For example, you could say: “I’ve always been able to balance my budget without any problems, but lately I’m very confused.” Ask any family or friends who have noticed changes to provide examples that you can share. Your doctor will probably want you to have a thorough check-up to see what might be causing your symptoms.

It is often helpful to bring a written list of your questions, in order of importance. Write down your symptoms, and bring along a family member or friend to the appointment, if possible. It’s helpful to make a list of your other medical conditions and all of your medications, including any over-the-counter drugs or supplements that you take.

For cognitive changes, some questions to consider asking your provider include:

• What do you think is causing my memory/thinking problems?
• Do I need to get any special tests done?
• Should I see a specialist like a neurologist, geriatrician, psychiatrist, or psychologist?
• Are there any recommendations to help improve my symptoms?
• Are there any other resources that you would recommend to learn more about my symptoms or what to do next?

How can I help a loved one who has mild cognitive impairment?

• Try to keep a positive attitude –use resources around you such as family, friends and community resources to make sure that you are as healthy and happy as you can be.
• Be proactive and make arrangements early for: 

• Insurance 
• Wills
• Power of attorney 

Family/friend care partners of people living with cognitive impairment are at increased risk of mental health issues like depression and anxiety. It’s important that you look after your own mental and physical health if you are a care partner for someone with MCI. Learn more about caregiver wellness from our iGeriCare e-learning lesson.

Where can I get help? Where can my family get support?

In addition to talking with your health care team, the following resources may also be helpful for you.

• Alzheimer Society of Canada. The Alzheimer Society of Canada is the leading nationwide health charity supporting people living with all forms of dementia, including Alzheimer’s disease, as well as their caregivers and their families. Call toll-free: 1-800-616-8816; email: info@alzheimer.ca; or visit their website at alzheimer.ca.
• 211 is a great resource for information about government and community-based social services, as well as some non-clinical health services. It’s a free and confidential service operating in pretty much every province and territory, and serving people in more than 150 languages, by phone, chat, text, and web. Dial 2-1-1 or go to 211.ca. If you are in Ontario, you can visit 211 Ontario.
• YMCA. The YMCA is a charity that has been helping Canadians improve their lives since the first Y opened in Montreal in 1851. YMCA programs are offered at more than 1,700 locations across Canada and help more than 2.25 million people annually become healthier in spirit, mind, and body. Find a location near you and see what programs they might offer for older adults. Visit their website at ymca.ca.
• Canadian Mental Health Association. With 330 community locations, CMHA is a nationwide organization that promotes mental health and supports people recovering from mental illness. Find Canadian Mental Health Association in your area.
• If you live in Ontario:
  • If you are concerned about significant changes in behaviour due to a brain disorder then Behaviour Supports Ontario regional programs may be able to help. Learn more about behaviour change in older adults and their initiatives on their website.
  • Learn more about home and community care programs and services in the province on the government of Ontario website.
  • You can also talk to a registered nurse – day or night – for free, secure and confidential health advice with Ontario’s Health811 service. Just call 811. Learn more about how to connect to care 24/7 with Health811, find a service, or chat online with a registered nurse through the ontario.ca/health website.

Where can I find out more information? 

If you haven’t reviewed our e-learning lesson about Mild Cognitive Impairment, that’s another good educational resource.

On the McMaster Optimal Aging Portal, we have several evidence-based articles related to MCI, including the following:

• Can treatment prevent dementia in people with mild cognitive impairment?
• Computer brain games for treating cognitive impairment?
• Not as sharp as you used to be? Exercises for your brain might help keep it fit

Key points from this detailed overview 

• The changes associated with aging are subtle. Some degree of cognitive decline is normal and expected as we age. However, the changes associated with normal aging don’t impact a person’s ability to function independently.
• Mild cognitive impairment or MCI (also known as Mild Neurocognitive Impairment), is diagnosed by a physician when people, their families, or friends notice that their memory and thinking skills have shown some signs of decline. There is evidence of some cognitive decline, it’s noticeable, but it doesn’t interfere significantly with day-to-day function or activities or independence, and is not as severe as dementia.
• There is an increased risk of going on to develop dementia; but many people with MCI do not get worse, and some may even have improvement depending on the cause.
• There are many potential causes for MCI, and some may be reversible or managed. A comprehensive assessment will try to rule out any reversible causes of cognitive impairment, such as medication side effects or other medical conditions. Cognitive screening tests like the MoCA or MMSE will be done as well, and there might also be a need for blood tests or brain imaging.
• While there are no specific treatments for MCI, managing other health conditions and healthy lifestyle behaviours can help to reduce your risks of developing MCI and help to promote brain health. General brain health may be improved with the right combination of diet, exercise, social and cognitive activity, and managing blood vessel health (such as blood pressure and blood cholesterol control). Diabetes management and cognitive training may also be somewhat helpful. The more of these lifestyle behaviours that you can do, the better.

You can learn more about reducing your risk of dementia by reviewing our Promoting Brain Health topic.