Mild cognitive impairment (MCI)

This page explains what mild cognitive impairment (MCI) is and tells you about some of the main symptoms.

What is mild cognitive impairment?

Mild cognitive impairment (MCI) is a condition in which someone has minor problems with cognition – their mental abilities such as memory or thinking. In MCI these difficulties are worse than would normally be expected for a healthy person of their age. However, the symptoms are not severe enough to interfere significantly with daily life, and so are not defined as dementia.

It is estimated that between 5 and 20% of people aged over 65 have MCI. It is not a type of dementia, but a person with MCI is more likely to go on to develop dementia. This page explains what MCI is, the link between MCI and dementia, and the benefits of diagnosing MCI. It then looks at treatments for MCI, ways to cope with the symptoms, and how you can reduce your risk of developing MCI and dementia. Many people who are diagnosed with MCI use this as an opportunity to change their lifestyle for the better. There is a lot that someone can do to help reduce their chances of MCI progressing to dementia.

Symptoms of mild cognitive impairment 

The term MCI describes a set of symptoms, rather than a specific disease. A person with MCI has mild problems with one or more of the following:

• memory – for example, forgetting recent events or repeating the same question

• reasoning, planning or problem-solving – for example, struggling with thinking things through

• attention – for example, being very easily distracted

• language – for example, taking much longer than usual to find the right word for something

• visual depth perception – for example, struggling to interpret an object in three dimensions, judge distances or navigate stairs.

These symptoms may have been noticed by the individual, or by those who know them. For a person with MCI, these changes may cause them to experience minor problems or need a little help with more demanding daily tasks (for example paying bills, managing medication, driving). However, MCI does not cause major problems with everyday living. If there is a significant impact on everyday activities, this may suggest dementia.

Most healthy people experience a gradual decline in mental abilities as part of ageing. In someone with MCI, however, the decline in mental abilities is greater than in normal ageing. For example, it’s common in normal ageing to have to pause to remember directions or to forget words occasionally, but it’s not normal to become lost in familiar places or to forget the names of close family members.

If the person with MCI has seen a doctor and taken tests of mental abilities, their problems will also be shown by a low test score or by falling test scores over time. This decline in mental abilities is often caused by an underlying illness.