Delirium

•    Clinical features:

o    Acute onset (hours to days), fluctuating course.

o    Inattention (hallmark), disorganised thinking, altered consciousness.

o    Often worse in the evening (“sundowning”).

•    Common causes (PINCH ME mnemonic):

o    Pain

o    Infection (e.g., UTI, pneumonia)

o    Nutrition (malnutrition, B12)

o    Constipation

o    Hydration (dehydration, electrolyte disturbance)

o    Medications (e.g., opiates, anticholinergics, benzodiazepines)

o    Environmental change (hospitalisation)

•    Management:

o    Identify and treat cause.

o    Avoid benzodiazepines unless alcohol withdrawal.

o    Reorientation strategies, minimize sensory impairments (glasses, hearing aids).

Dementia

•    Key differences from delirium:

o    Insidious onset, progressive.

o    Usually alert consciousness in early stages.

o    No fluctuation day-to-day.

•    Types:

o    Alzheimer’s disease:

    Early episodic memory impairment, parietal/temporal atrophy on MRI.

    Risk factors: age, ApoE4 allele.

o    Vascular dementia:

    Stepwise decline, focal neurological signs.

    Imaging: multiple infarcts, white matter changes.

o    Dementia with Lewy bodies:

    Visual hallucinations, fluctuating cognition, parkinsonism.

    Severe neuroleptic sensitivity.

o    Frontotemporal dementia:

    Early personality change, disinhibition, executive dysfunction.

    May present with language variant (primary progressive aphasia).

Drug-Induced Psychiatric Symptoms

•    Corticosteroids:

o    Can cause mania, psychosis, mood lability.

•    Levodopa:

o    Visual hallucinations, confusion, psychosis.

•    Alcohol withdrawal:

o    Tremor, agitation, hallucinations (visual or tactile), seizures.

o    Delirium tremens: severe autonomic instability, hallucinations, mortality risk.

•    Other:

o    Interferon-alpha → depression.

o    Beta-blockers → depressive symptoms.

o    Anticholinergics → confusion, delirium (especially in elderly).

Medical Conditions Presenting with Psychiatric Symptoms

•    Endocrine:

o    Hypothyroidism: depression, psychosis (“myxoedema madness”).

o    Hyperthyroidism: anxiety, irritability.

o    Cushing’s syndrome: depression, mania.

•    Neurological:

o    Epilepsy: interictal psychosis.

o    Temporal lobe epilepsy: hallucinations, personality change.

o    Encephalitis (esp. HSV): psychiatric symptoms, memory deficits.

•    Autoimmune and metabolic:

o    SLE: psychosis, mood disturbance, cognitive changes.

o    Wilson’s disease: personality change, psychosis (young adults).

Capacity and Consent

•    Four-stage test (Mental Capacity Act):

o    Understand the information given.

o    Retain the information long enough to make a decision.

o    Weigh the information to reach a choice.

o    Communicate their decision (any means).

•    Key principles:

o    Presume capacity unless proven otherwise.

o    Capacity is decision- and time-specific.

o    Patients with capacity have the right to refuse treatment, even if this leads to harm.

Extra Revision Pearls

•    Delirium is associated with increased mortality and risk of long-term cognitive decline.

•    Lewy body dementia = "visual hallucinations before memory loss"; sensitive to antipsychotics (can worsen parkinsonism).

•    Always consider thyroid, B12, and syphilis serology in new-onset cognitive or psychiatric symptoms.

•    Reversible causes of dementia (“Dementia mimics”): depression (“pseudodementia”), NPH, hypothyroidism, B12 deficiency.