Dementia Clinical Overview
I. The "On-Call" Snapshot
Clinical Significance in Malaysia: Dementia is a major geriatric syndrome. With Malaysia projected to be an aged nation by 2030, you will be at the forefront of diagnosing and managing its complications. Your primary role is to identify cognitive impairment, rule out acute/reversible causes (like delirium), and initiate a safe management and discharge plan.
High-Yield Definition (Source: Malaysian CPG on Dementia, 2nd Ed.):
Dementia is a clinical syndrome characterised by a progressive global decline in cognitive abilities in clear consciousness. This decline must be severe enough to interfere with daily social or occupational functioning. It involves impairment in at least two of the following domains: memory, reasoning, orientation, language, and attention.
Clinical One-Liner: "This is a chronic, progressive brain failure, unlike delirium, which is an acute, fluctuating confusional state."
II. Etiology & Risk Factors
Etiology:
Primary (Irreversible):
Alzheimer's Disease (AD): Most common (60-70%). Caused by amyloid-beta plaques and neurofibrillary (tau) tangles.
Vascular Dementia (VaD): Second most common. Caused by cerebrovascular disease (multi-infarct or small vessel disease). Often co-exists with AD ("Mixed Dementia").
Dementia with Lewy Bodies (DLB): Caused by alpha-synuclein (Lewy body) deposits.
Frontotemporal Dementia (FTD): Caused by tau or TDP-43 proteinopathy.
Reversible/Secondary Causes (Your job is to find these):
Drugs (e.g., anticholinergics, benzodiazepines)
Emotional (Depression, "pseudodementia")
Metabolic (Thyroid, B12/Folate deficiency, uraemia, hepatic encephalopathy)
Eyes/Ears (Severe sensory impairment)
Normal Pressure Hydrocephalus (NPH)
Tumour/Trauma (Subdural haematoma, brain tumour)
Infection (Neurosyphilis, HIV, TB)
Alcohol (Wernicke-Korsakoff)
Risk Factors:
Non-Modifiable: Advancing age (strongest risk factor), family history, genetic factors (e.g., APOE e4 allele).
Modifiable (Vascular): Hypertension, diabetes mellitus, hyperlipidaemia, smoking, obesity. (Common in our local population).
Other: Lower education level, traumatic brain injury, social isolation.
III. Quick Pathophysiology
Think of it simply:
Alzheimer's: Misfolded proteins (amyloid and tau) accumulate, acting as "rubbish" that poisons neurons, particularly in the hippocampus (memory) and temporal/parietal lobes (language, navigation). This leads to synaptic loss and neurodegeneration.
Vascular: "Plumbing problem." Multiple small or large strokes damage brain tissue. The deficits are stepwise and relate to the vascular territory affected. It's about cumulative ischaemic damage.
DLB: Lewy bodies deposit in the cortex and brainstem. This disrupts cholinergic and dopaminergic pathways, causing the classic triad of cognitive fluctuation, visual hallucinations, and parkinsonism.
IV. Classification
Clinically, you must differentiate the "Big 4":
Alzheimer's Disease (AD):
Hallmark: Insidious onset, progressive memory loss (amnestic presentation) is the first and most prominent feature.
Vascular Dementia (VaD):
Hallmark: Stepwise decline, often with a clear temporal link to a stroke. Features depend on the location of infarcts (e.g., gait issues, focal weakness).
Dementia with Lewy Bodies (DLB):
Hallmark Triad:
Fluctuating cognition (patient is fine in the morning, very confused by evening).
Recurrent, well-formed visual hallucinations (e.g., "seeing small children").
Spontaneous parkinsonism (bradykinesia, rigidity).
Pearl: Extreme sensitivity to neuroleptics (antipsychotics) – can cause severe parkinsonism or NMS-like reaction.
Frontotemporal Dementia (FTD):
Hallmark: Presents young (<65). Personality and behavioural changes (disinhibition, apathy, poor hygiene) or language impairment (progressive non-fluent aphasia) are the first features. Memory is often spared early on.
V. Clinical Assessment
🚩 Red Flags & Immediate Actions:
Acute/Sudden Onset of Confusion:
Action: Full delirium screen (review in-out chart, vital signs, physical exam, sepsis/metabolic workup).
Reason: This is delirium until proven otherwise. Dementia is chronic.
Fluctuating Consciousness (GCS dropping):
Action: ABCDE assessment, check BUSE/LFT/TFT/B12, septic workup, urgent CT Brain.
Reason: Rule out life-threatening causes (e.g., intracranial bleed, hypoglycaemia, sepsis, hepatic encephalopathy).
New Focal Neurological Deficit (e.g., hemiparesis, aphasia):
Action: Activate stroke protocol. Urgent CT Brain.
Reason: This is a stroke, which could be the cause of a new vascular dementia, but the acute event must be managed first.
Aggression, Wandering, Acute Safety Risk:
Action: 1:1 nursing, review medications, consider minimal dose of short-acting antipsychotic (e.g., Haloperidol 0.5mg stat) after ruling out pain/delirium.
Reason: Patient and staff safety is paramount. This is a common Behavioural and Psychological Symptom of Dementia (BPSD).
History (From Patient and a Reliable Informant/Caregiver):
Key Diagnostic Clues:
Onset & Progression: Insidious and slow (AD) vs. Stepwise (VaD) vs. Rapid (Creutzfeldt-Jakob Disease - rare).
Dominant Symptom: Memory loss first (AD) vs. Personality/behaviour change first (FTD) vs. Gait/incontinence/cognition triad (NPH) vs. Hallucinations/fluctuation (DLB).
Symptom Breakdown (Domains):
Memory: Forgetting recent events, repeating questions.
Language: Word-finding difficulty (anomia).
Executive Function: Difficulty managing finances, planning meals, medication compliance.
Visuospatial: Getting lost in familiar places.
Behaviour: Apathy, disinhibition, agitation, paranoia.
Pertinent Negatives:
No acute onset (rules out delirium/stroke).
No recent medication changes (rules out drug-induced cognitive impairment).
No major depressive symptoms (rules out pseudodementia).
Physical Examination (OSCE Approach):
General Inspection: Look for signs of self-neglect, cachexia, or evidence of trauma (falls).
Vitals: Usually normal in dementia. Fever/tachycardia suggests infection (possible delirium).
Disease-Specific Examination (Full Neurological Exam):
Cognitive Screen (Bedside):
MOCA (Montreal Cognitive Assessment): Preferred, more sensitive for mild cognitive impairment (MCI).
MMSE (Mini-Mental State Examination): Quick and traditional.
Clock Drawing Test: Excellent quick screen for executive and visuospatial function.
Look for Focal Deficits: Pyramidal weakness, sensory loss, visual field defects suggest Vascular Dementia.
Look for Parkinsonism: Bradykinesia, lead-pipe rigidity, resting tremor. Suggests DLB or Parkinson's Disease Dementia (PDD).
Gait: "Magnetic" apraxic gait (feet stuck to floor) is classic for NPH. Broad-based/ataxic gait suggests vascular or cerebellar pathology.
Primitive Reflexes: Grasp, pout, palmomental reflexes may reappear in advanced dementia (frontal lobe release signs).
Pertinent Negatives: Normal power, tone, and reflexes (common in early AD).
Examination for Differentials:
Look for signs of hypothyroidism (goitre, dry skin), B12 deficiency (peripheral neuropathy), or liver disease (jaundice, asterixis).
Differentiating Disease Stage:
Early / Mild (CDR 1): Impaired Instrumental ADLs (IADLs) like managing money, transport, complex tasks. Socially competent.
Intermediate / Moderate (CDR 2): Impaired Basic ADLs (BADLs) like dressing, bathing, toileting. Behavioural issues (BPSD) often peak here.
Late / Severe (CDR 3): Fully dependent for all care. Often non-verbal, bed-bound.
Clinical Pearl: Always get a collateral history. The patient is by definition an unreliable historian. If the family says, "He's not himself," but the patient's MMSE is 30/30, trust the family and do a MOCA.
VI. Diagnostic Workflow
Differential Diagnosis:
Delirium:
Points For: Acute onset, fluctuating course, impaired attention, underlying illness (e.g., UTI, pneumonia).
Points Against: Chronic, progressive course.
Differentiate: History (use the CAM - Confusion Assessment Method), collateral history, and finding the underlying acute cause.
Depression ("Pseudodementia"):
Points For: Patient complains ("I have memory problems"), prominent anhedonia/low mood, "don't know" answers.
Points Against: Patient tries to hide deficits, mood is secondary to cognitive frustration.
Differentiate: Trial of antidepressants (if depressed), neuropsychological testing.
Normal Pressure Hydrocephalus (NPH):
Points For: Classic Triad: "Wet, Wobbly, Wacky" (Urinary Incontinence, Gait Apraxia, Cognitive Decline).
Points Against: Absence of the triad, prominent memory loss as a first symptom.
Differentiate: CT/MRI Brain showing ventriculomegaly. Confirmed by CSF tap test (Miller-Fisher test) showing improved gait. This is a crucial reversible cause to identify.
Investigations Plan (The "Dementia Screen"):
Bedside / Initial:
Cognitive Assessment: MOCA or MMSE.
Vitals: Rule out sepsis/hypoxia.
ECG: Check for AF (risk for VaD).
First-Line Labs (To rule out reversible causes):
Full Blood Count (FBC): Anaemia.
Renal Profile (RP) / BUSE: Uraemia, electrolyte imbalance.
Liver Function Test (LFT): Hepatic encephalopathy.
Thyroid Function Test (TFT): Hypothyroidism.
Vitamin B12 / Folate: Deficiency.
VDRL / TPHA: Neurosyphilis (less common, but treatable).
Fasting Blood Sugar / HbA1c: Assess vascular risk.
First-Line Imaging (All new dementia diagnoses):
CT Brain (non-contrast):
Why: Essential to rule out structural lesions (tumour, subdural, NPH) and extensive vascular disease.
Findings: May show generalised or focal (e.g., medial temporal lobe) atrophy.
MRI Brain: More sensitive for specific atrophy patterns, small vessel disease, and differentiating dementia subtypes, but less available and more expensive.
Confirmatory / Gold Standard:
Diagnosis is clinical. There is no single "gold standard" test.
Specialised Tests (by specialist): CSF analysis (for Aβ/tau levels), PET scans (FDG or amyloid) are research tools and not routine in Malaysian government hospitals.
VII. Staging & Severity Assessment
We use the Clinical Dementia Rating (CDR). It's a global scale based on a structured interview with the patient and informant.
CDR 0: Normal
CDR 0.5: Mild Cognitive Impairment (MCI) - Cognitive decline present, but no significant interference with daily function.
CDR 1: Mild Dementia
CDR 2: Moderate Dementia
CDR 3: Severe Dementia
Why it matters: The CDR score, along with functional assessment (IADL/BADL), dictates the level of supervision and support needed, and guides therapy.
VIII. Management Plan
A. Principle of Management:
Rule out and treat reversible causes.
Symptomatic treatment with cognitive enhancers.
Manage Behavioural and Psychological Symptoms of Dementia (BPSD).
Support the caregiver and plan for long-term safety.
B. Immediate Stabilisation (The ABCDE Plan):
This is not applicable to a chronic, stable dementia diagnosis.
If the patient presents with superimposed delirium (acute confusion), you manage that aggressively:
A/B/C: Ensure vitals are stable.
D: Stop all offending drugs (e.g., anticholinergics, benzos).
E: Expose to find the cause (e.g., check for urinary retention, faecal impaction, pressure sores, sepsis). Treat the underlying trigger.
C. Definitive Treatment (The Ward Round Plan):
(As per Malaysian CPG on Dementia)
1. Non-Pharmacological (FIRST-LINE for all stages):
Cognitive Stimulation: Puzzles, reminiscence therapy.
Environmental Modification: Clocks, calendars, good lighting, safe environment (remove rugs, install grab bars).
Caregiver Education & Support: Crucial. Manage expectations, link to support groups (e.g., Alzheimer's Disease Foundation of Malaysia - ADFM).
2. Pharmacological (For Mild-to-Moderate AD/DLB):
Cholinesterase Inhibitors (AChEIs):
Drug: T. Donepezil (start 5mg ON, max 10mg ON) OR Rivastigmine patch.
MOA: Increases acetylcholine levels. Provides modest symptomatic benefit.
S/E: GI upset (nausea, diarrhoea), bradycardia (check ECG first).
3. Pharmacological (For Moderate-to-Severe AD):
NMDA Receptor Antagonist:
Drug: T. Memantine (start 5mg OD, titrate up).
MOA: Blocks excitotoxicity from glutamate. Can be used as monotherapy or added to an AChEI.
4. Management of BPSD:
Non-pharma first: Identify and remove triggers (pain, constipation, noise). Use distraction, re-orientation.
Pharma (if risk of harm): "Start low, go slow."
T. Trazodone: Good for sundowning/agitation with insomnia.
Antipsychotics (Risperidone, Haloperidol): Use with extreme caution. Associated with increased stroke/mortality in elderly with dementia. Avoid in DLB.
D. Long-Term & Discharge Plan:
Follow-up: Regular 3-6 monthly follow-up with primary care or geriatric clinic to monitor cognition (MOCA) and function.
Medication: Ensure compliance, review for side effects.
Social: Refer to Jabatan Kebajikan Masyarakat (JKM) if social/financial issues. Discuss respite care, daycare centres.
Safety: Driving cessation, kitchen safety.
Advance Care Planning: Discuss prognosis and ceiling of care with family.
IX. Complications
BPSD: Agitation, aggression, psychosis. The main reason for institutionalisation.
Falls: Due to gait instability, weakness, and poor judgment.
Aspiration Pneumonia: Late-stage complication due to dysphagia.
Malnutrition & Dehydration: Forgetting to eat/drink.
Pressure Ulcers: Immobility in late-stage disease.
Caregiver Burnout: A major clinical and social complication. Always ask how the caregiver is coping.
X. Prognosis
Dementia is progressive and life-shortening.
Average survival from diagnosis is variable:
AD: ~8-12 years.
VaD: ~5 years (due to underlying cardiovascular comorbidity).
DLB/FTD: More rapid decline, ~6-8 years.
Prognostic Factors: Earlier onset, male sex, and presence of BPSD or parkinsonism generally predict a more rapid decline.
XI. How to Present to Your Senior
(Example SBAR for a new referral from clinic)
"Dr. [Senior's Name], I am calling about a new admission from the clinic, Mdm. [Name], a 75-year-old female from bed [Number].
S (Situation): She was referred for a 1-year history of progressive cognitive decline, now impacting her ADLs.
B (Background): She has underlying hypertension and diabetes. Her family reports she has been getting lost, repeats questions, and recently left the stove on. Her MOCA score in the clinic was 16/30. She has no acute complaints, and her vitals are stable.
A (Assessment): My initial assessment suggests a progressive dementia, likely Alzheimer's or mixed type. I have clerked her, and the physical exam is unremarkable except for the cognitive score. I've sent off the full "dementia screen" labs (TFT, B12, etc.) and ordered a plain CT Brain as per the CPG. I've also assessed for BPSD and caregiver stress, which seem manageable for now.
R (Recommendation): My plan is to await the blood and CT results to rule out reversible causes. I will start her on T. Donepezil 5mg ON after the CT and a baseline ECG are done. I also plan to refer her to the social worker for caregiver support and schedule a family conference. Is this plan agreeable?"
XII. Summary & Further Reading
Top 3 Takeaways:
Dementia is chronic; Delirium is acute. Your first job is to distinguish them.
Always perform the "Dementia Screen" (Bedside cognition, Labs, CT Brain) to find and treat reversible causes.
Management is holistic: It's not just about Donepezil. It's about non-pharma strategies, managing BPSD, and supporting the caregiver.
Key Resources:
Malaysian CPG: Clinical Practice Guidelines on Management of Dementia (Second Edition)
UpToDate: "Clinical features and diagnosis of Alzheimer disease" and "Evaluation of cognitive impairment and dementia"
Amboss: "Dementia"
