Psychosocial, Behavioral & Cognitive · Topic 3 of 7

Dementia in the Hospitalized Older Adult

Psychosocial · older adult in the hospital

Dementia in the Hospitalized Older Adult

Any new decline is delirium until proven otherwise. Look for the physical trigger, manage behavior without drugs, and remember antipsychotics raise mortality in dementia.

Key numbers

Antipsychotics raise death risk in dementia1.6–1.7× mortality

01 · The ruleNew decline means delirium until proven otherwise

Delirium often complicates dementia: any new behavioral or cognitive deterioration — even when it looks like sundowning — is presumed delirium until proven otherwise and prompts a search for the cause.

02 · AvoidAntipsychotics raise death risk in dementia

All antipsychotics carry an FDA boxed warning: older adults with dementia-related psychosis have 1.6–1.7 times the risk of death (about 4.5% vs 2.6% over 10 weeks), mostly cardiovascular or infectious.

03 · The ruleNonpharmacologic first; antipsychotic only if dangerous

AGS Beers 2023: avoid antipsychotics for behavioral symptoms of dementia unless nonpharmacologic options have failed and the patient threatens substantial harm to self or others; if used, deprescribe toward the lowest effective dose.

Causes & risk factors

Why it happens

Look for pain, retention, constipation, infection must knowAgitation in dementia is often triggered by a physical problem the patient cannot communicate — pain, urinary retention, constipation, dyspnea or infection — so examine and treat before medicating the behavior.

Do right now

In this order

First moves

New decline means delirium until proven otherwise

→

Look for pain, retention, constipation, infection

→

Nonpharmacologic first; antipsychotic only if dangerous

Why each step

New decline means delirium until proven otherwiseDelirium often complicates dementia: any new behavioral or cognitive deterioration — even when it looks like sundowning — is presumed delirium until proven otherwise and prompts a search for the cause.

Look for pain, retention, constipation, infectionAgitation in dementia is often triggered by a physical problem the patient cannot communicate — pain, urinary retention, constipation, dyspnea or infection — so examine and treat before medicating the behavior.

Nonpharmacologic first; antipsychotic only if dangerousAGS Beers 2023: avoid antipsychotics for behavioral symptoms of dementia unless nonpharmacologic options have failed and the patient threatens substantial harm to self or others; if used, deprescribe toward the lowest effective dose.

Management

Orders

Brexpiprazole: approved for Alzheimer agitationBrexpiprazole is FDA-approved for agitation associated with Alzheimer dementia (start 0.5 mg daily, target 2 mg, max 3 mg); it is not for PRN use and still carries the boxed mortality warning.

No capacity: turn to the health care proxyIf capacity cannot be restored, decisions go to the agent named in the durable power of attorney for health care or another legally authorized surrogate; emergency care proceeds under presumed consent when none is available.

Reorient, mobilize and use sitters, not restraintsManage hospital behavior with a calm, well-lit, consistent environment, clocks and family photos, glasses and hearing aids, daytime activity and sleep at night, and sitters or family instead of physical restraints.

Treat depression in dementia with an SSRITreat depression in dementia with a non-anticholinergic antidepressant, preferably an SSRI; avoid tricyclics.

Red flags & don'ts

Avoid harm

Avoid benzodiazepines and anticholinergics in dementia avoidAvoid benzodiazepines, Z-drug hypnotics and strongly anticholinergic drugs (diphenhydramine, oxybutynin, tricyclics) in dementia — they worsen cognition and precipitate delirium (AGS Beers 2023).

Lewy body dementia: avoid haloperidol avoidDementia with Lewy bodies and Parkinson disease dementia show extreme sensitivity to antipsychotics: avoid haloperidol and other typical agents; if one is unavoidable, use quetiapine or clozapine, or pimavanserin for Parkinson disease psychosis.

Antipsychotics also cause stroke, EPS and falls complicationBeyond mortality, antipsychotics in dementia raise stroke risk and cognitive decline and cause extrapyramidal symptoms, tardive dyskinesia, sedation and falls; atypicals add weight gain and diabetes risk.

The rules

Know these

Capacity is decision-specific, not diagnosis-specificA dementia diagnosis does not by itself remove capacity: capacity is judged for each decision against its complexity, and a patient too impaired for a complex choice may still be able to name a surrogate.

Don't diagnose dementia during deliriumDementia is diagnosed only when deficits do not occur exclusively during delirium; defer formal cognitive testing (MMSE, MoCA) until the acute illness and delirium have cleared.

Delirium or dementia?

Commonly confused

Main deficit	Attention
Onset	Hours to days
Usual cause	Acute illness or drug toxicity
Reversibility	Often reversible
New behavioral decline in a known dementia	Presume this first

More detail

Reference

Show 5 reference facts

When a behavioral drug is used in dementia, reassess the need at least monthly and taper toward the lowest effective dose or stop.

Cholinesterase inhibitors (donepezil, rivastigmine, galantamine) modestly improve cognition in Alzheimer disease and Lewy body dementia; memantine helps moderate to severe disease and may be combined with them.

Check for treatable contributors to cognitive impairment — hypothyroidism, vitamin B12 deficiency, neurosyphilis and depression — and for drugs whose clearance falls with new kidney or liver failure.

In advanced dementia, palliative measures may be more appropriate than aggressive hospital care; decisions about artificial feeding are best made, with advance directives, before the need arises.

Rapidly progressive dementia evolves within 1–2 years; prion disease is the most common cause, followed by autoimmune and paraneoplastic encephalitis.

Pearl

In dementia, behavior is communication: find the pain, the full bladder or the infection before you find a drug.

Sources · Merck Manual Professional — Dementia · Merck Manual Professional — Behavioral and Psychologic Symptoms of Dementia · Merck Manual Professional — Delirium (sundowning; general measures) · Seroquel (quetiapine) prescribing information — boxed warning and §5.1 Increased Mortality in Elderly Patients with Dementia-Related Psychosis — DailyMed · Rexulti (brexpiprazole) prescribing information — indications, dosage for agitation associated with Alzheimer dementia, boxed warning — DailyMed · American Geriatrics Society 2023 Updated AGS Beers Criteria (Table 2 antipsychotics/benzodiazepines; Table 3 dementia, delirium, Parkinson disease). J Am Geriatr Soc 2023;71:2052–2081 · Merck Manual Professional — Dementia With Lewy Bodies and Parkinson Disease Dementia · Merck Manual Professional — Capacity, Competence, and Incapacity · Starter sheet built from the verified AGACNP fact map (facts reviewed 2026-10-15).