Neurocognitive Disorders

Overview

• Neurocognitive disorders (NCDs) include two major syndromes:
  • Delirium – acute, short-term, fluctuating disturbance of attention + cognition.
  • Dementia (Major/Mild NCD) – chronic, progressive decline in ≥ one cognitive domain that interferes with independence.

Delirium vs Dementia

• Onset: Delirium $\text{hrs–days}$; Dementia $\text{mo–yrs}$.
• Consciousness: Delirium altered; Dementia usually clear.
• Course: Delirium reversible when cause treated; Dementia gradually worsens.
• Common delirium precipitants: infection, dehydration, polypharmacy, substance intox/withdrawal, metabolic derangements.

DSM-5 Dementia Categories (key examples)

• Alzheimer’s disease (AD)
• Vascular NCD
• Lewy body disease
• Frontotemporal lobar degeneration
• TBI-related, Substance/Medication-induced, HIV, Prion, Parkinson’s, Huntington’s

Etiology Highlights

• AD: amyloid plaques; strongest risk = age; ↑ in women; risks – TBI, Down syndrome, vascular disease.
• Vascular: cerebrovascular events, hypertension → reduced cerebral blood flow; risk rises sharply > $65$ yr.
• Lewy body: abnormal α-synuclein deposits.
• Frontotemporal: ≈ $40\%$ familial; MAPT, GRN, C9ORF72 mutations.
• Other causes: TBI, HIV, Prion (contaminated meat / genetic), Huntington (autosomal dominant), Parkinson (basal ganglia loss).

Core Cognitive Domains Affected

• Executive function: planning, decision-making.
• Complex attention: sustain, divide, switch attention.
• Learning & memory: new info, short-term recall.
• Language: naming, fluency, comprehension.
• Perceptual-motor: visuospatial, navigation.
• Social cognition: recognition of social norms, empathy.

Alzheimer’s Diagnostic Criteria (DSM-5)

• Insidious onset + gradual progression.
• ≥ $2$ impaired domains (one must be memory/learning).
• No extended plateaus; no mixed etiology.
• Genetic evidence (mutation or family history) strengthens diagnosis.

Alzheimer’s Manifestations by Stage

• Mild: subtle memory lapses, misplacing items, neologisms, ↓ planning/organization.
• Moderate: disorientation to time/place, ADL assistance, confabulation, wandering, sundowning.
• Severe: profound communication & motor loss, atypical behaviors (hostility), agraphia, hyperorality, hypermetamorphosis.

Key Features of Other Dementias

• Frontotemporal: early personality/behavior change (disinhibition, apathy), or progressive aphasia.
• Lewy body: fluctuating cognition, visual/tactile hallucinations, spontaneous parkinsonism, REM sleep behavior disorder, neuroleptic sensitivity.
• Vascular: stepwise decline, slowed processing, executive dysfunction.
• TBI: LOC, post-traumatic amnesia, neuro signs; severity graded by Glasgow Coma Scale, duration of LOC & amnesia.

Safety Essentials

• Home: supervise, secure exits, remove hazards/weapons, stove/temperature controls, ID & GPS devices.
• Inpatient: ensure sensory aids, adequate lighting, minimal mirrors, hallway rails, ID bracelets; avoid restraints, use anxiolytics judiciously.

Nursing Assessment (Recognize Cues)

• Screen mood (depression, hostility, suicidality), cognition (hallucinations, confabulation), ADLs, communication (word-finding, neologisms), vitals, labs.
• Focus patterns: sundowning (AD), risky behaviors (frontotemporal), REM sleep disorder (Lewy body), stroke signs (vascular), seizures (TBI), psychomotor slowing (drug-induced).

Diagnostics

• MMSE scores: $22–26$ mild, $18–20$ moderate, $0–10$ severe.
• AD: PET for amyloid; functional staging (eight-stage scales).
• Vascular/TBI: CT or MRI.
• Frontotemporal: CT/MRI.
• Lewy body: clinical hx.
• Huntington: genetic test.

Nursing Interventions

• Person-centered planning; involve family early; connect to resources (Alzheimer’s Association, respite care, hospice).
• Communication: calm voice, reality reinforcement, short phrases, limit choices.
• Non-pharmacologic: orientation aids, music/reminiscence, safe environment, ADL support, MIND diet rich in flavanols & $\omega$-$3$.
• Complementary: massage, aromatherapy (lemon, rosemary, lavender), research on turmeric, ginkgo.

Pharmacologic Overview

• Delirium: treat cause; benzodiazepines for DTs.
• Alzheimer’s symptoms: cholinesterase inhibitors (donepezil, rivastigmine, galantamine, tacrine); disease-modifying – aducanumab.
• Lewy body: antipsychotics with caution (↑ sensitivity); treat parkinsonism.
• Vascular: antiplatelets/anticoagulants, statins, BP control.
• Parkinson’s dementia: levodopa, COMT inhibitors.
• HIV: antiretrovirals.
• Huntington’s chorea: tetrabenazine.

Evaluation

• Reassess cognition & behavior regularly.
• Monitor medication adherence/effectiveness & side effects.
• Evaluate caregiver burden; recommend respite/support services.