Which of the following is NOT listed as a delirium risk factor?

• A. Immobility
• B. Regular exercise
• C. Polypharmacy
• D. Dehydration

Answer: (B)

Delirium risk rises from factors that reduce brain resilience and precipitate acute cognitive dysfunction. Immobility contributes by promoting deconditioning, reducing sensory and environmental stimulation, and increasing vulnerability to infections and metabolic disturbances. Dehydration disrupts fluid and electrolyte balance and can impair cerebral perfusion, tipping the brain toward delirium. Polypharmacy raises the risk because many medications, especially anticholinergics and sedatives, directly affect attention and awareness. Regular exercise, in contrast, strengthens cerebral perfusion, improves sleep, reduces inflammation, and enhances overall functional reserve, making delirium less likely. Therefore, regular exercise is not listed as a delirium risk factor; it is protective.