Mild Neurocognitive Disorder in Adults

Mild neurocognitive disorder is characterized by moderate cognitive decline from a prior level of performance in one or more cognitive domains:

• Complex Attention: tasks take longer to complete than previously, work needs to be double-checked for errors, difficulty thinking and processing information when multi-tasking (i.e., talking on a cell phone and driving)
• Executive Functions: requires more effort to finish multistep projects, trouble resuming a task that was interrupted, has difficulty organizing, planning or making decisions, trouble following shifting conversations
• Learning and Memory: difficulty recalling recent events, relies on reminders and list-making
• Language: word-finding difficulty, grammatical errors in expressive language
• Perceptual-Motor: may rely more heavily on maps or notes for directions, may expend more effort on motor tasks such as typing, knitting, or assembly
• Social Cognition: minor changes in behavior or personality, less ability to read social cues such as facial expressions, decreased empathy, or decreased inhibition  

The acquired cognitive decline is noted by concern on part of the individual, a knowledgeable informant, or the clinician. The cognitive performance is also evaluated through an objective neuropsychological assessment, with performance compared with norms appropriate to the patient's age, educational attainment, and cultural background, to determine if the performance within the cognitive domains falls below the expected level. Mild neurocognitive performance deficits are typically defined as 1-2 standard deviations below average (between the 3rd and 16th percentiles).

Neurodegenerative diseases such as Alzheimer’s disease or frontotemporal lobar degeneration are associated with a slow onset and steady progression of symptoms. Environmental and genetic factors also vary by subtype and age of onset within the subtypes. Overall, the strongest risk factor for major and mild neurocognitive disorders is age due to the increased risk of neurodegenerative and cerebrovascular disease.

Individuals with neurocognitive disorders can present with a wide variety of mood disturbances including depression, apathy, anxiety, and elation. Sleep disturbance is also common and may include symptoms of insomnia, hypersomnia, or circadian rhythm disorder. Delirium commonly co-occurs with neurocognitive disorders in the older population. For younger individuals, neurodevelopmental disorders such as attention-deficit/hyperactivity disorder are a frequent comorbidity.

The following are links to treatment recommendations based on the causal diagnosis:

• Alzheimer’s Disease
• Frontotemporal lobar degeneration
• Lewy body disease
• Vascular disease
• Traumatic brain injury
• Substance/medication use
• HIV infection
• Prion disease
• Parkinson’s disease
• Huntington’s disease
• Multiple etiologies
• Unspecified