Cognitive Impairment Signs and Diagnosis

Core Clinical Signs

Cognitive impairment is characterized by a decline from previous levels of functioning in one or more cognitive domains, which may range from mild deficits to severe impairment affecting daily functioning 1, 2
Repetitive questions or conversations are a common sign of memory impairment 1, 2
Difficulty learning and retaining new information is a key feature of cognitive impairment 3
Poor understanding of safety risks and inability to manage finances are indicative of executive function impairment 2
Difficulty finding common words while speaking and hesitations in speech are signs of language impairment 2
Inability to recognize faces or common objects and difficulty finding objects in direct view despite good acuity are indicative of visuospatial impairment 2
Difficulties with simple and divided attention are a common feature of attention and processing speed impairment 3

Uncharacteristic mood fluctuations or agitation, impaired motivation or initiative, and apathy or loss of drive are common behavioral changes in individuals with cognitive impairment 2
Social withdrawal, decreased interest in previous activities, and loss of empathy are also frequent behavioral changes 2

Mild Cognitive Impairment (MCI) is characterized by modest cognitive decline from previous performance, with cognitive test scores typically 1-1.5 standard deviations below age and education-matched peers 3, 5, 6
Major Neurocognitive Disorder (Dementia) is marked by significant cognitive decline from previous performance, with substantial impairment in cognitive performance and interference with independence in everyday activities 1, 2

A comprehensive clinical evaluation should include obtaining history from both patient and knowledgeable informant, conducting objective cognitive assessment, and assessing at least two cognitive domains 2, 8
Standardized cognitive assessment tools should be considered, and changes in functional abilities should be evaluated 7, 8
Common pitfalls in identifying cognitive impairment include relying solely on patient self-report, failing to obtain collateral information, and attributing cognitive changes to normal aging 6, 8

Delirium, major psychiatric disorders, and neurodegenerative disorders such as Alzheimer's disease, Lewy body disease, and frontotemporal dementia should be considered in the differential diagnosis of cognitive impairment 2, 4