Mild Neurocognitive Disorder / Mild Cognitive Impairment (MCI)

Mild Neurocognitive Disorder (also known as Mild Cognitive Impairment, or MCI) is a condition in which individuals demonstrate cognitive impairment with minimal impairment of instrumental activities of daily living (IADLs). Although it can be the first cognitive sign of Alzheimer's Disease (AD), it can also be secondary to other disease processes (e.g. - neurologic, other neurodegenerative disorders, systemic, infectious, or psychiatric disorders). When there is interference with independence in everyday activities, a major neurocognitive disorder needs to be considered instead.

  • Prevalence is between 10-20% in adults over 65 years.
  • This is a heterogeneous group with variable rates of conversion to dementia.
  • Anywhere between 3 to 13% of patients with mild neurocognitive disorder will progress to major neurocognitive disorder each year.[1]
  • Neuropsychiatric symptoms will be present in 35-75% of cases.
Risk Factors
Criterion A

Evidence of modest cognitive decline from a previous level of performance in 1 or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual motor, or social cognition) based on:

  1. Concern of the individual, a knowledgeable informant, or the clinician that there has been a significant decline in cognitive function; and
  2. A substantial impairment in cognitive performance, preferably documented by standardized neuropsychological testing or, in its absence, another quantified clinical assessment.
Criterion B

The cognitive deficits do not interfere with capacity for independence in everyday activities (i.e. - complex instrumental activities of daily living such as paying bills or managing medications are preserved, but greater effort, compensatory strategies, or accommodation may be required).

Criterion C

The cognitive deficits do not occur exclusively in the context of a delirium.

Criterion D

The cognitive deficits are not better explained by another mental disorder (e.g., major depressive disorder, schizophrenia).

Etiology Specifier

Behaviour Specifier


  • Without behavioural disturbance: If the cognitive disturbance is not accompanied by any clinically significant behavioral disturbance.
  • With behavioural disturbance (specify disturbance): If the cognitive disturbance is accompanied by a clinically significant behavioural disturbance (e.g. - psychotic symptoms, mood disturbance, agitation, apathy, or other behavioural symptoms).
Vitamin D

Improvements in cognition and lipid levels are seen in individuals with long-term supplementation of Vitamin D.[2]