Vascular Dementia

Related Subjects: |Causes of Stroke |Ischaemic Stroke |Dementias |Abbreviated Mental Test Score (AMTS) |Alzheimer disease |Dementia with Lewy bodies |Frontotemporal dementia |Corticobasal degeneration |Creutzfeldt Jakob disease |Vascular Dementia |Small Vessel Disease |CADASIL |CARASIL |Anti Dementia Drugs |AIDS Dementia Complex |Normal Pressure Hydrocephalus |Acetylcholinesterase inhibitors |Mental Capacity Act 2005 |Behavioural and Psychological Symptoms of Dementia

🧠 About

• Vascular dementia (VaD) is the second most common cause of dementia after Alzheimer’s. It is caused by impaired cerebral blood flow leading to cumulative brain injury.
• Classically presents with a stepwise decline in cognition following strokes or transient ischaemic attacks (TIAs). ⬇️
• Often coexists with Alzheimer’s pathology (“mixed dementia”).

⚙️ Aetiology

• Strategic infarcts: Lesions in critical areas (e.g. bilateral caudate, medial thalamus, hippocampus, parietal lobe) → profound cognitive impairment.
• White matter disease: Binswanger’s disease – diffuse subcortical ischaemia causing gait and executive dysfunction.
• Genetic: CADASIL (NOTCH3 mutation) – hereditary small vessel disease presenting with migraine, strokes, and early dementia. 👨‍👩‍👧
• Pathology may include reduced CSF acetylcholine, hence occasional partial response to cholinesterase inhibitors.

⚠️ Risk Factors

• Prior stroke or TIA ⏱️
• Hypertension, diabetes, dyslipidaemia 🩸
• Atrial fibrillation, valvular disease ❤️
• Smoking 🚬, obesity, sedentary lifestyle

🩺 Clinical Features

• Stepwise decline: Periods of stability punctuated by abrupt deterioration after vascular events.
• Focal neurological signs: Hemiparesis, hemisensory loss, visual field defects.
• Pyramidal signs: Spasticity, hyperreflexia, Babinski response. 🦵
• Pseudobulbar palsy: Dysarthria, dysphagia, emotional lability (pathological crying/laughing).
• Subcortical features: Dyspraxic gait, “marche à petits pas” (tiny shuffling steps), parkinsonism, urinary incontinence.
• Frontal lobe changes: Disinhibition, poor judgment, apathy, executive dysfunction. 🤯

🔍 Investigations

• Bloods: FBC, U&E, LFTs, TFTs, B12, folate → exclude reversible causes.
• ECG + CXR: Look for AF, cardiomegaly, heart failure or pulmonary disease.
• CT/MRI brain:
  • Subcortical white matter ischaemia
  • Lacunar infarcts 🟤
  • Cortical & subcortical infarcts
  • Microbleeds (suggest hypertension or cerebral amyloid angiopathy)
• Doppler/echo: Assess carotids and cardiac embolic sources when relevant.

💊 Management

• Vascular risk reduction: Stop smoking, optimise BP, glucose and lipids. 🫀
• Antiplatelets: Aspirin or clopidogrel for secondary stroke prevention (unless contraindicated).
• Anticoagulation: For AF or valvular disease if CHA₂DS₂-VASc score high.
• Statins: For dyslipidaemia and vascular protection. 🌟
• Cholinesterase inhibitors (donepezil, rivastigmine): Limited role, considered if mixed with Alzheimer’s pathology.
• Supportive care: Physiotherapy, occupational therapy, cognitive stimulation, caregiver support.

📌 Exam Pearls

✅ Stepwise deterioration + focal neurological signs → think vascular dementia.
✅ Contrast with Alzheimer’s (gradual onset, memory-led) and Lewy body dementia (fluctuating cognition + hallucinations + parkinsonism).
✅ Always investigate and treat modifiable vascular risks (BP, AF, diabetes, cholesterol).

📖 References

• NICE CKS – Dementia (vascular)
• Alzheimer’s Society – Vascular dementia

Cases - Vascular Dementia

• Case 1 - Stepwise Decline: A 72-year-old man with a history of hypertension and atrial fibrillation develops sudden memory loss and impaired executive function after a stroke. Over the next 3 years, his cognition worsens in a stepwise fashion after further TIAs. Diagnosis: Multi-infarct vascular dementia. Management: Secondary prevention (antiplatelet, anticoagulation for AF, statin, BP control); cognitive rehabilitation; MDT support.
• Case 2 - Subcortical Ischaemic Changes: A 68-year-old woman with diabetes and long-standing hypertension presents with progressive slowness, difficulty planning, and urinary incontinence. MRI brain: extensive white matter small vessel disease. Diagnosis: Subcortical vascular dementia (Binswanger’s disease). Management: Control vascular risk factors; physiotherapy for gait; cholinesterase inhibitors sometimes trialled but less effective than in Alzheimer’s.
• Case 3 - Post-Stroke Cognitive Impairment: A 75-year-old man had a left MCA stroke 9 months ago. Since then, he struggles with problem-solving and attention, though memory recall is relatively preserved. Diagnosis: Vascular cognitive impairment following major stroke. Management: Stroke rehab; vascular risk reduction; carer support and occupational therapy.

Teaching Commentary 🧠

Vascular dementia is the second most common cause of dementia after Alzheimer’s. It results from cumulative cerebrovascular injury (multiple infarcts, small vessel disease, strategic single infarcts). Key clinical patterns: - Stepwise decline (multi-infarct). - Subcortical small vessel disease: executive dysfunction, gait problems, incontinence. - Post-stroke cognitive impairment. Risk factors mirror stroke: hypertension, diabetes, smoking, AF. Management is vascular risk reduction + supportive cognitive/functional therapy. Unlike Alzheimer’s, cholinesterase inhibitors have limited evidence, but may be used in mixed dementia.