MCI and Dementia

Mild Cognitive Impairment

  • When cognitive function is impaired by some underlying disease or condition, the earliest and subtlest stages of impairment are called mild cognitive impairment (MCI). Although it is frequently mis-stated, MCI is not a diagnosis, but rather a “stage” or “severity” of the cognitive impairment due to some underlying medical conditions.

    If the cause of MCI is not treated, the condition often progresses until the individual becomes more impaired or “demented.” According to widely accepted definitions, persons with MCI have impairments limited to one category of cognitive function (e.g. memory, judgment, reasoning, executive function) and this impairment does not interfere with performing activities of daily living.

    MCI is also identified as the first clinical stage of Alzheimer’s disease (AD). The subtype of MCI associated with AD is called amnestic MCI and affects an individual's memory. Approximately 80% of people with amnestic MCI develop AD within 6 years. According to the Mayo Clinic, 15-20% of MCI patients progress to dementia each year. In comparison, the progression rate for the general population is 1-2%. Since MCI is the first symptomatic stage of AD, accurately detecting MCI enables medical professionals to then take the steps necessary to determine if a patient has early stage AD and might benefit from timely intervention.