Vascular dementia

Definition
Vascular dementia is a progressive cognitive decline caused by reduced blood flow to the brain, leading to neuronal damage. It is the second most common cause of dementia after Alzheimer’s disease and results from one or more cerebrovascular events or chronic small vessel disease.

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Causes and Pathophysiology

• Large vessel disease – multiple cortical infarcts from major stroke(s)

• Small vessel disease – lacunar infarcts and chronic ischemia from arteriolosclerosis

• Hypoperfusion – due to cardiac arrest, severe hypotension

• Mixed dementia – vascular dementia with Alzheimer’s pathology

• Underlying risk factors:

  • Hypertension

  • Diabetes mellitus

  • Atrial fibrillation

  • Hyperlipidaemia

  • Smoking

  • Carotid artery disease

  • Previous stroke or transient ischaemic attacks (TIAs)

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Types

1. Multi-infarct dementia – stepwise decline after multiple strokes

2. Subcortical vascular dementia – gradual decline due to small vessel disease (e.g., Binswanger’s disease)

3. Strategic single-infarct dementia – due to a single stroke in a critical cognitive area (e.g., thalamus, hippocampus)

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Clinical Features

• Cognitive symptoms:

  • Problems with attention, concentration, and executive function (planning, organising)

  • Slowed thinking and processing

  • Memory impairment (less prominent early than in Alzheimer’s)

• Behavioural and mood changes:

  • Depression, apathy, emotional lability

• Neurological signs (depend on stroke location):

  • Weakness or numbness

  • Gait disturbance

  • Urinary incontinence

  • Pseudobulbar palsy

• Course:

  • Stepwise deterioration in multi-infarct dementia

  • Gradual decline in small vessel disease

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Diagnosis

• History and examination – link onset/progression to cerebrovascular events

• Cognitive assessment: MMSE, MoCA

• Neuroimaging:

  • MRI – most sensitive for small vessel disease, infarcts, white matter hyperintensities

  • CT – useful to detect infarcts or haemorrhage

• Vascular assessment: carotid Doppler, ECG, echocardiogram

• Blood tests: screen for vascular risk factors (lipid profile, glucose, HbA1c), rule out reversible causes of cognitive impairment

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Treatment

1. Address underlying vascular causes and prevent further damage

• Control blood pressure, blood sugar, and cholesterol

• Antiplatelet agents (e.g., aspirin, clopidogrel) unless contraindicated

• Anticoagulation in atrial fibrillation (e.g., warfarin, DOACs)

• Smoking cessation, weight management, physical activity, healthy diet

2. Cognitive and symptomatic management

• Cholinesterase inhibitors (donepezil, rivastigmine) and memantine are not routinely recommended for pure vascular dementia but may be used in mixed dementia cases

• Treat depression, anxiety, and sleep disorders

• Occupational therapy, physiotherapy, and speech therapy for functional improvement

3. Supportive care

• Education for patient and caregivers

• Home safety adaptations to prevent falls

• Social services support and respite care

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Prognosis

• Progressive condition with variable rate of decline depending on stroke recurrence and comorbidities

• Life expectancy is often reduced due to underlying cardiovascular disease

• Early diagnosis and aggressive vascular risk factor control can slow progression