How can I differentiate between MCI and early-stage dementia during patient assessments?

To differentiate between mild cognitive impairment (MCI) and early-stage dementia during patient assessments, follow these key steps:

• Take a detailed history from the patient and, if possible, from someone who knows them well, focusing on cognitive, behavioural, and psychological symptoms and their impact on daily life. MCI typically involves cognitive decline without significant interference in daily functioning, whereas early dementia shows cognitive decline with clear functional impairment ¹.
• Use validated brief structured cognitive tests such as the 10-point cognitive screener (10-CS), 6-item cognitive impairment test (6CIT), Mini-Cog, or Test Your Memory (TYM). These help identify cognitive impairment but do not alone confirm dementia ¹.
• Supplement history with informant questionnaires like the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) or the Functional Activities Questionnaire (FAQ) to assess changes in function and cognition over time, which are more pronounced in dementia ¹.
• Conduct physical examination and appropriate blood and urine tests to exclude reversible causes of cognitive decline, which can mimic dementia ¹.
• Refer to specialist dementia diagnostic services if dementia is still suspected after initial assessment and reversible causes are excluded. Specialists can perform further cognitive testing, neuropsychological assessments, and imaging to confirm dementia diagnosis and subtype ¹.
• Recognise that MCI does not meet criteria for dementia because it lacks significant functional impairment, whereas early dementia involves cognitive decline sufficient to interfere with independence ¹.

In summary, the differentiation hinges on the presence of functional impairment alongside cognitive decline, assessed through history, informant reports, cognitive testing, and exclusion of reversible causes, with specialist referral when dementia is suspected.