Geriatric Psychiatry: Cognition, Function, and Polypharmacy
Geriatric questions emphasize distinguishing normal aging from pathology, differentiating delirium, dementia, and depression, and managing polypharmacy. Know that delirium is acute and fluctuating, dementia is chronic and progressive, and depression can mimic cognitive impairment (pseudodementia) but often coexists. Alzheimer disease is the most common dementia; vascular, Lewy body (visual hallucinations, parkinsonism, fluctuation), and frontotemporal (behavioral or language variants) dementias have distinct profiles. Behavioral and psychological symptoms of dementia require nonpharmacologic approaches first.
Traps
- Missing delirium superimposed on dementia.
- Using anticholinergic or sedating drugs that worsen cognition.
- Overlooking drug interactions and renal dosing in older adults.
- Assuming cognitive decline is inevitable rather than evaluating reversible causes.
Rule of thumb
For any older patient with new cognitive change, screen for delirium first, then evaluate reversible causes (medications, thyroid, B12, infection, depression). Worked example: an 82-year-old becomes confused overnight after starting a bladder antimuscarinic-suspect anticholinergic delirium, stop the drug, and reassess rather than labeling dementia.