The Confusion Assessment Method (CAM) and Mini-Mental State Exam (MMSE) can be used in combination to effectively differentiate delirium from dementia, respectively.
CAM relies on observations by family members, caregivers, and clinicians to assess the following four symptoms:
acute confusional onset
inattention
disorganized thinking
ltered level of consciousness
Using CAM, the diagnosis of delirium requires the presence of both the first and second features, plus one of the two other features.
CAM is 95-100% sensitive and 95% specific for diagnosing delirium in the elderly.
MMSE is not a diagnostic tool but identifies cognitive impairment suggestive of delirium by assessing orientation, short-term memory, calculation ability, and language (score 18-26 = mild dementia).
A positive CAM and an MMSE score of > 25 is predictive of delirium.