Mild Cognitive Impairment (MCI) is a condition that affects people's memory and/or thinking. These difficulties are usually mild, hence the name, but are worse than what is expected of a healthy person at that age. The symptoms of MCI are not severe enough to impact a person's daily life, so they are not defined as dementia.
Understanding Mild Cognitive Impairment (MCI) is important as it helps us understand changes in our capacity to think and recall memories as we grow older. Being able to recognise MCI early on is important, as this could be a potential sign of future cognitive decline. Catching signs and symptoms of MCI early is crucial, especially as they can have negative implications for our everyday lives. Various interventions and treatments exist for MCI, which will be discussed in more detail below.
MCI has been defined as falling between the normal healthy ageing that people experience with memory, speech, and thinking and more serious cognitive decline such as dementia. By targeting MCI early on, it may be possible to delay the progression of dementia in older populations. In a study conducted in 2022, the global prevalence of MCI in populations of adults over 50 years old was 15.56%.1 So, 15.56% of the world's over-50 population suffers from some form of MCI. In the following sections, we will explore the symptoms, causes, risk factors, how it is diagnosed, and how MCI is managed and treated.
Understanding mild cognitive impairment
Definition and classification
Diagnosing MCI can be difficult. Because the condition affects everyone differently and has many different causes, it could take longer to get a definite diagnosis. The first step towards getting a diagnosis if you or a loved one are worried about your memory is to visit a qualified health professional. Getting a diagnosis can be frightening. A qualified health professional will likely need to hear about the symptoms you are experiencing and will give you a physical examination to test coordination, reflexes, and movement and check both memory and thinking skills. You may also need blood tests to see if symptoms could be due to another health condition.
If other health conditions have been ruled out, you may need a referral to a memory clinic or specialist clinic for further diagnosis. This could include brain scans, further memory and thinking tests, and a procedure called a Lumbar Puncture to test for warning signs of dementia.
Two main subtypes of MCI are classified based on the specific cognitive areas that are affected:
- Amnestic MCI is the first subtype. This is mainly related to memory problems, where people may experience issues recalling recent events, conversations, or information such as appointments. This subtype of MCI is usually associated with an increased risk of Alzheimer’s disease.
- Non-amnestic MCI is the second subtype and affects skills such as language, attention, and visuospatial skills (our visual perceptions; an example would be making a bed) and executive functions (such as the ability to organize a task). This subtype of MCI can be caused by various factors and can be associated with different types of dementia.
Cognitive deficits in MCI are considered not too severe, and while people might experience some issues with memory or difficulties with their thinking abilities, they do not usually interfere considerably with normal performance. People exhibiting MCI can still usually live independently and handle essential daily tasks such as cooking and personal hygiene. They are also able to maintain healthy relationships and engage in conversations and activities. However, they may experience some memory lapses or the odd forgotten word.
Many people diagnosed with MCI are also able to continue working, especially if their job does not heavily require memory-intensive tasks. People with MCI are often aware of the changes in their memory or thinking.
Recognizing symptoms and early signs
Common symptoms of MCI include:2
- Forgetting or struggling to find the right words during conversations
- Forgetting things more often than usual (problems with memory)
- Issues with attention span, becoming more easily distracted
- Issues with visual perception, finding it more difficult to climb stairs or judge distances
- Becoming irritable, upset, or having a low mood
It is important to be able to distinguish between normal age-related memory changes and MCI. Recognising the differences in symptoms can be essential for early diagnosis and intervention and allows people to better understand their cognitive health. By recognizing potential early signs or symptoms, an individual can proactively maintain or improve cognitive health through various risk factors. More details on this are included below.
Causes and risk factors
MCI can be caused by a variety of sources; below are some identified in research.
As we age, areas in the brain that are responsible for memory and thinking can shrink or change. These changes can cause lapses between the pathways in the brain that communicate with each other by sending messages, causing delays and issues with memory recall. Reduced blood flow and oxygen supply have also been shown to play a role in the development of MCI3
Our family history and the genes (DNA) we inherit from our parents can also impact the risk of developing MCI. If you have close relatives, such as parents or grandparents, who experience cognitive issues or dementia, your risk of developing MCI may be higher due to the DNA you share.
Smoking and increased alcohol consumption have also been associated with an increased likelihood of MCI, as these can damage blood vessels in the brain, causing a lack of blood flow. They can also affect chemicals that transmit signals in the brain (neurotransmitters) that can negatively impact cognitive health.
It is important to consider that multiple factors could be causing the symptoms of MCI, and while we cannot control all risk factors, maintaining a healthy lifestyle and being socially and mentally stimulated can help reduce the risks.
Identifying risk factors
Being able to understand the risk factors can be the first step in helping to protect our cognitive health.
Research has shown that maintaining good cardiovascular health is essential when wanting to maintain a healthy brain.4 This is because our cardiovascular health is closely linked to other conditions, such as high blood pressure and diabetes, which also have an impact on the development of MCI as they can both cause reduced blood flow to the brain.5
Other risk factors associated with MCI include:
- Age – the risk of MCI increases with age.
- Family History – having close relatives who suffer from MCI or dementia.
- Lifestyle choices—smoking, drinking excessive alcohol, eating an unhealthy diet, and being physically inactive are all associated with developing MCI.
- Mental and Social Engagement – keeping the brain mentally stimulated can lower the risk of MCI.
- Medical Conditions – Sleep apnea, vitamin deficiencies, and depression potentially all act as risk factors for MCI.
Managing these risk factors is key to ensuring good cognitive health.
Diagnosis and assessment
If you are experiencing any symptoms related to MCI, seeking advice from a healthcare professional is crucial. It is important to remember that not all memory and thinking issues are caused by MCI and that other conditions may be the source. If, however, your healthcare professional suspects MCI as the cause, an early intervention can potentially slow down any further cognitive decline and provide ways to manage symptoms.
During a review with a healthcare professional, medical history will need to be discussed, including any potential family history of cognitive disorders, to help understand any potential risk factors or genetic predispositions relating to the symptoms. Various tests may be used to evaluate memory, speech, and other thinking abilities that will provide the healthcare provider with the information they need to potentially make a diagnosis.
If necessary, brain imaging such as an MRI or CT might be used to help look at potential structural brain changes or to rule out other conditions such as a stroke, the combination of the above aids healthcare professionals in making a timely and accurate diagnosis.6
Occasionally, forgetting things is a part of getting older, but how do we know when these lapses highlight something more worrying?
Age-related changes are usually minor; however, MCI demonstrates more persistent and noticeable problems that go beyond these age-related changes. MCI does not impact daily life; dementia, on the other hand, often significantly impacts daily life and an individual's independence.
An accurate diagnosis is crucial for the proper management of MCI. It allows for early identification and timely interventions, which can slow down symptoms of cognitive decline and improve quality of life. It also helps identify possible underlying causes so that the correct treatments can be given. Ensuring an accurate diagnosis also allows individuals and their families to plan for the future and ensure the person can contribute to any important decisions.
Management and support
Evidence suggests that various lifestyle interventions can help with cognitive function. Below are some examples that reduce the risk of cognitive decline:
- Regular physical activity.
- Balanced, healthy diets rich in fruits, vegetables, whole grains, and healthy fats.
- Being socially active with friends and family.
Cognitive training and rehabilitation
Memory training exercises are made to challenge the brain. These can include memorizing lists, playing memory games, or recalling past events. Other examples can focus on problem-solving and critical thinking skills, which keep the mind active and engaged to reduce the risk of cognitive decline.
Research has shown that regular memory training exercises can improve cognitive abilities and possibly delay the onset of MCI or even dementia.
Follow-up and monitoring
MCI may be a warning sign of future cognitive decline, including dementia; however, the good news is that early detection allows for management to support cognitive functions and slow down the progression. Regular follow-ups with a healthcare professional can help track any cognitive changes, allowing for proactive management.
MCI can be an early warning sign of further cognitive decline. Recognising and understanding the symptoms, such as mild memory loss or problems with attention span, early on can help address these changes and aid in a quicker diagnosis. Maintaining a healthy lifestyle by eating a balanced diet, not smoking, and not excessively drinking alcohol can lower the risk of MCI and contribute to maintaining good cognitive function.
Multiple factors contribute to the development of MCI, and it is possible that other conditions may be the cause, so if you or a loved one notice any of the symptoms mentioned above, do not hesitate to contact a healthcare professional for advice.
- MCI is a cognitive condition that falls between normal age-related cognitive changes and more severe decline, such as dementia.
- There are various risk factors associated with MCI, including Cardiovascular conditions, lifestyle factors, brain changes, and genetics.
- Diagnosing MCI early is important to aid in delaying further cognitive decline and improving quality of life.
- Treatment of MCI involves a combination of factors. Maintaining a healthy lifestyle and keeping your brain active are important for maintaining a healthy brain.
- Bai W, Chen P, Cai H, Zhang Q, Su Z, Cheung T, et al. Worldwide prevalence of mild cognitive impairment among community dwellers aged 50 years and older: a meta-analysis and systematic review of epidemiology studies. Age Ageing. 2022 Aug 2;51(8).
- Mild Cognitive Impairment (MCI) | Symptoms & Treatments | alz.org [Internet]. [cited 2023 Jul 29]. Available from: https://www.alz.org/alzheimers-dementia/what-is-dementia/related_conditions/mild-cognitive-impairment
- Tang T, Huang L, Zhang Y, Li Z, Liang S. Aberrant pattern of regional cerebral blood flow in mild cognitive impairment: A meta-analysis of arterial spin labeling magnetic resonance imaging. Front Aging Neurosci. 2022 Sep 1;14:961344.
- Xu C, Tao X, Ma X, Zhao R, Cao Z. Cognitive Dysfunction after Heart Disease: A Manifestation of the Heart-Brain Axis. Oxid Med Cell Longev [Internet]. 2021 Aug;2021:4899688. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8387198/
- Zou Y, Zhu Q, Deng Y, Duan J, Pan L, Tu Q, et al. Vascular Risk Factors and Mild Cognitive Impairment in the Elderly Population in Southwest China. Am J Alzheimers Dis Other Demen [Internet]. 2014 May;29(3):242–7. Available from: https://doi.org/10.1177/1533317513517042
- Langa KM, Levine DA. The diagnosis and management of mild cognitive impairment: A clinical review. Vol. 312, JAMA - Journal of the American Medical Association. American Medical Association; 2014. p. 2551–61.