Dementia and major NCD — assessment, BPSD, and pharmacotherapy (MEQ)

(i) Formulation. Working diagnosis: major neurocognitive disorder with a probable dementia with Lewy bodies (DLB) phenotype — progressive functional decline plus core features of cognitive fluctuations, recurrent well-formed visual hallucinations, and REM sleep behaviour disorder (dream enactment). Acute problem: delirium superimposed on dementia, precipitated by UTI and hospital environment, with secondary aggression. Discriminators: not pure late-onset primary psychosis (progressive multi-domain decline and RBD); not typical amnestic-only AD as the sole explanation (early fluctuations/hallucinations/RBD). Still complete medical work-up and consider mixed pathology.[1][3]

(ii) Immediate agitation management. Treat as medical emergency of behaviour: ABCDE, treat UTI and other delirium drivers, orientation, low-stimulus environment, pain/constipation/retention check, family presence if helpful. Do not start regular olanzapine or depot. In DLB, antipsychotics risk severe neuroleptic sensitivity. If imminent danger persists after non-drug measures, any psychotropic is last-line, lowest dose, shortest time, with mortality counselling (Schneider meta-analysis increased death risk; CATIE-AD modest efficacy/high adverse effects; DART-AD withdrawal often safer long-term). Prefer specialist advice before antipsychotics in DLB.[1][2][3][7][8]

(iii) Longer-term pharmacotherapy. After delirium clears, consider a cholinesterase inhibitor. Rivastigmine has pivotal evidence in related Lewy body disease (PDD — Emre): titrate carefully (e.g. oral start around 1.5 mg twice daily with stepwise increases, or transdermal 4.6 then 9.5 mg/24 h per product information), monitor GI effects and heart rate. Donepezil 5 mg daily for 4 weeks then 10 mg is the AD backbone and may be used depending on phenotype and local pathways; DOMINO-AD supports continuation benefit in moderate–severe AD contexts. Memantine (titrate 5 mg daily by 5 mg weekly to 10 mg twice daily) is primarily moderate–severe AD evidence (Reisberg/Tariot/Cochrane) — optional if AD-mixed features. BPSD: DICE-style non-drug plan first; antipsychotics not for maintenance wandering.[4][5][3]

(iv) Capacity for discharge destination. Decision-specific assessment using Appelbaum abilities: understand options (home with package vs residential care), appreciate personal risks (night wandering, falls), reason comparatively, communicate a consistent choice. Optimise hearing, language, timing (not at peak delirium). If lacking capacity for that decision, use jurisdiction-specific substitute decision-maker / guardianship pathways — name the principle of least restriction without inventing section numbers. Document process.[6]