Which feature best distinguishes delirium from dementia at the bedside?

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Multiple Choice

Which feature best distinguishes delirium from dementia at the bedside?

Delirium versus dementia is defined by how cognition changes over time. Delirium shows an acute or subacute onset with fluctuations in arousal and attention—patients’ alertness and clarity can wax and wane over hours to days, and inattention is prominent. This often points to an underlying medical issue, such as infection, metabolic disturbance, or medication effect, and the cognitive impairment can appear suddenly and be reversed with treatment. Dementia, on the other hand, is a chronic, progressive decline in multiple cognitive domains with a gradual onset. Attention and alertness are not acutely fluctuating in the early to middle stages, and the course is typically steady rather than episodic. So the feature that best distinguishes delirium at the bedside is the combination of acute onset and fluctuating consciousness with inattention, setting it apart from the gradual, chronic course seen in dementia. The other descriptions misstate onset, fluctuation, or chronicity.

Delirium versus dementia is defined by how cognition changes over time. Delirium shows an acute or subacute onset with fluctuations in arousal and attention—patients’ alertness and clarity can wax and wane over hours to days, and inattention is prominent. This often points to an underlying medical issue, such as infection, metabolic disturbance, or medication effect, and the cognitive impairment can appear suddenly and be reversed with treatment.

Dementia, on the other hand, is a chronic, progressive decline in multiple cognitive domains with a gradual onset. Attention and alertness are not acutely fluctuating in the early to middle stages, and the course is typically steady rather than episodic.

So the feature that best distinguishes delirium at the bedside is the combination of acute onset and fluctuating consciousness with inattention, setting it apart from the gradual, chronic course seen in dementia. The other descriptions misstate onset, fluctuation, or chronicity.

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