Mild cognitive impairment (MCI) is a condition that affects a person’s thinking and memory skills, but not enough to significantly affect day-to-day life. In contrast, dementia can cause significant memory loss, confusion, personality changes, and disability.

In comparison to MCI, dementia is more serious. It interferes with daily life and is often progressive, meaning it gets worse over time.

MCI can be an early stage of dementia, but not everyone with MCI will go on to develop dementia. Many people with MCI remain stable or get better.

This article provides an overview of MCI versus dementia and addresses common questions about their differences.

An older woman washing her face in a bathroom.Share on Pinterest
Willie B. Thomas/Getty Images

MCI is a mild loss of memory or other cognitive abilities. It is more pronounced than the typical cognitive changes that come with aging but less pronounced than dementia. The condition does not prevent a person from performing most of their usual activities.

Doctors classify MCI into two types based on the symptoms: amnestic MCI and nonamnestic MCI.

Amnestic MCI affects memory, whereas nonamnestic MCI does not. Instead, people with nonamnestic MCI experience changes to other thinking skills, such as decision making, time judgment, and visual/spatial perception.

Some people with MCI get better or remain stable, while others may go on to develop dementia.

“Dementia” is a general term for a decline in cognitive abilities that interferes with the ability to perform everyday activities. This condition often affects those aged 65 or older and is usually progressive. It is not a typical part of aging — rather, it is a serious medical condition.

The symptoms of dementia can vary but may include:

  • memory loss
  • difficulty communicating
  • confusion
  • lack of judgment
  • personality changes
  • difficulty with problem solving
  • agitation or aggression

The most common type of dementia is Alzheimer’s disease, which accounts for around 70–80% of cases. Other forms of dementia are vascular dementia, Lewy body dementia, and frontotemporal dementia.

Both MCI and dementia affect cognitive abilities, but they do so to different degrees. The table below summarizes the differences:

mild effect on daily functioningsignificant effect on daily functioning
minor issues with memorysevere issues with memory
minor difficulty concentratingsevere issues with concentration
some struggles with planning and organizinginability to plan or organize
slight difficulty following conversationinability to hold meaningful conversations
no personality changespersonality changes
ability to walk and balancetrouble walking or frequent falls

People with dementia do not necessarily have all of these symptoms, nor do they have them all at once. Dementia is a progressive illness, and the symptoms can change over time.

In some cases, MCI may progress to dementia. An estimated 10–20% of people aged 65 or older with MCI develop dementia within a year.

However, many people with MCI do not develop dementia at all. In some cases, people improve, returning to their former cognitive abilities.

Doctors make a diagnosis of MCI using their best professional judgment. They will take a thorough medical history to document symptoms, other medical conditions, and any family history of dementia.

First, they will rule out other potential causes of a person’s memory difficulties, such as mental health issues, medications, or stroke.

Next, they will perform a comprehensive evaluation of the individual’s thinking and memory abilities. They may order tests to rule out Alzheimer’s disease, including imaging tests — such as brain PET scans — or spinal fluid tests.

If a person has amyloid beta protein in their spinal fluid, this indicates amyloid plaques in the brain, a sign of Alzheimer’s.

The doctor will also assess the person’s ability to function and attempt to determine whether their abilities are changing. They will test the person’s mental status, reflexes, coordination, balance, and senses.

If the person experiences substantial interference with daily life and the condition affects one or more of their cognitive abilities, a doctor may diagnose dementia rather than MCI. However, if the results are unclear, a doctor may recommend seeing a specialist for further testing.

Doctors currently have no standard treatment or medications for MCI. Instead, they may recommend strategies to help a person cope with changes in memory or other skills, such as:

  • maintaining a regular routine
  • using to-do lists and notes to remember things
  • using calendars, diaries, or apps to set reminders
  • putting important items, such as a wallet or keys, in the same place every day

A doctor may also suggest taking steps to look after a person’s health, particularly their brain health. These could include eating a balanced diet, getting regular exercise, getting enough sleep, and engaging in cognitive activities such as puzzles, reading, or classes to help maintain thinking skills.

Treatment for dementia is often more aggressive and may include medications that can slow down worsening symptoms. Cholinesterase inhibitors, which prevent the breakdown of certain brain chemicals, are one possible type of medication a doctor may prescribe. If necessary, a doctor may also recommend medications to help with depression, anxiety, and sleep issues.

People with dementia often need supportive care and may benefit from memory training and mental and social stimulation. However, there is not yet a cure for dementia.

Because MCI can be an early indication of more serious problems, people with this diagnosis should see their doctor every 6–12 months after diagnosis for re-evaluation.

MCI does not always lead to dementia. It can remain stable or even improve. However, experts are not yet sure why. As a result, there is no guaranteed way to prevent MCI from progressing to dementia.

Addressing risk factors for dementia may be helpful. A doctor may recommend taking steps to treat or prevent conditions that have links with dementia, such as:

Other strategies that may help reduce the risk include:

  • seeking support to stop smoking, if relevant
  • eating a nutritious diet
  • staying connected with friends or family
  • exercising regularly
  • making efforts to maintain a moderate weight
  • reducing to stopping alcohol consumption
  • seeking treatment for mental health conditions such as depression, if necessary
  • using hearing aids, in people with hearing impairments
  • protecting the ears from preventable hearing loss
  • avoiding air pollution, wherever possible

These measures cannot guarantee that a person will not develop dementia. However, according to a 2020 report in The Lancet, addressing risk factors may prevent or delay around 40% of dementia cases.

MCI causes subtle memory and thinking problems that do not significantly interfere with daily life. It can be an early indication of dementia but is not always.

Doctors diagnose MCI and dementia by taking a thorough medical history and performing cognitive and other tests to rule out other potential causes.

There is currently no cure for either condition, but people with MCI may be able to take steps to lower their risk of dementia. For those with dementia, medications are available to slow the progression of symptoms.