How would you differentiate delirium from schizophrenia in a hospitalized patient?

• A. Delirium is acute, fluctuating consciousness with impaired attention; schizophrenia is chronic psychosis; use CAM for delirium screening
• B. Delirium is chronic; schizophrenia is acute reversible
• C. Both are identical and should be treated the same
• D. Delirium never occurs in hospitalized patients

Answer: (B)

Onset and attention distinguish delirium from schizophrenia. Delirium is an acute change in mental status that develops over hours to days, with fluctuations in alertness and markedly impaired attention. In a hospitalized patient, this points to an underlying medical or pharmacologic issue that is potentially reversible and needs prompt evaluation and treatment. Schizophrenia, by contrast, is a chronic psychiatric illness characterized by long-standing symptoms such as delusions, hallucinations, and disorganized thinking, with consciousness typically clear and the illness persisting for months or years rather than showing acute fluctuation.

Guiding this differentiation is a delirium screening approach like the Confusion Assessment Method, which looks for acute onset with fluctuating course and inattention, plus either disorganized thinking or an altered level of consciousness. When these features are present, delirium is the likely explanation and requires urgent medical workup.

This also clarifies why the other ideas aren’t correct: delirium is not a chronic condition, and it can occur in hospitalized patients; schizophrenia is not defined by acute fluctuations in consciousness, and they are not treated as identical conditions.