Vascular Dementia: Causes, Diagnosis & Treatment

In vascular dementia, there is cognitive decline due to ischemic, hemorrhagic, or oligemic injury to the brain caused by vascular or cardiovascular disease.

History of Vascular Dementia

Kraeplin first described arteriosclerotic dementia in 1896.

Hachinski described multi-infarct dementia.

• He also gave a Hachinski ischemic score, which is used to evaluate the extent of vascular injury. The higher the value, the higher the damage.

Epidemiology of Vascular Dementia

• It is the third most common cause of dementia.
• Out of all the dementia cases, 10–20% of the cases are of pure vascular cause.
• Mixed etiology may have a higher prevalence.
• The highest risk factor for vascular dementia is age and evidence of vascular disease. There are also other vascular risk factors like diabetes, hypertension, congestive heart failure, atrial fibrillation, etc.
• It is more common in men.

Also read: Understanding Frontotemporal Dementia: Symptoms, Genetics, and Prognosis

Etiology of Vascular Dementia

1. Stroke

One of the leading causes of vascular dementia is stroke. Three subtypes of stroke include cortical, subcortical, and strategic infarct.

2. Hemorrhage

Another cause of vascular dementia is hemorrhage. Hemorrhagic stroke, subdural hematoma, epidural hematoma, and intraparenchymal hemorrhage/trauma can lead to cognitive impairment causing vascular dementia.

3. Chronic hypoperfusion
4. Cerebral amyloid angiopathy

It is found that many times, vascular dementia and Alzheimer's disease may occur together. They may have overlapping etiology and risk factors. Important etiology that helps us understand why this occurs includes: It is found that about 1/3 of patients with vascular neurocognitive dementia may have Alzheimer's disease neuropathology, and about 1/3 of patients with Alzheimer's disease have significant cerebrovascular disease.

• In vascular dementia, if the cause is stroke, it would lead to brain damage, subsequently leading to amyloidogenesis (soluble amyloid deposits, increased CSF with synaptophysin increase), which is similar to what can be observed in Alzheimer's disease.
• One of the factors leading to the high occurrence of the two is APOE4. This is due to the increased risk of dementia due to stroke and APOE4 being associated with high levels of LDL.
• Cerebrovascular diseases also cause cholinergic deficits, which is an important cause of Alzheimer's disease.
• They have common risk factors like diabetes, hypertension, hyperlipidemia, peripheral artery disease, and smoking.
• In the nun studies, in Alzheimer's disease, the brain infarct is a better predictor of dementia severity than the density of plaques and tangles.

Diagnosis of Vascular Dementia

• In DSM-5, there is major and minor neurocognitive dementia.
• Criteria A: Criteria met for major or minor neurocognitive dementia.
• Criteria B: Clinical features are consistent with vascular etiology, suggested by 1 or 2.
  • The onset of cognitive deficits is temporarily related to 1 or more cerebrovascular events
  • Evidence of decline is prominent in complex attention and frontal execution functions.

• Criteria C: Evidence of cerebrovascular disease. This includes history, physical examination, and/or neuroimaging sufficient to account for neurocognitive deficit.
• Criteria D: It should not be better explained by another brain disease or systemic disease.
• Probable vascular neurocognitive disorder may be seen if 1 of the following is present:
  • If there are clinical criteria and neuroimaging evidence present,
  • It is temporarily related to 1 or more documented cerebrovascular events.
  • Both clinical and genetic evidence of cerebrovascular events is present.

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Ninds-Airen Criteria

This criteria is commonly used for research purposes.

1. Clinical diagnosis of probable vascular dementia.
2. Deficits in memory and at least 2 other cognitive domains should be present.
   • Presence of focal neurological signs and symptoms and neuroimaging evidence of cerebrovascular disease.
   • The relationship between the two
3. Clinical features are consistent with vascular disease diagnosis. Includes early GAIT disturbance, falls, urinary symptoms, pseudobulbar palsy, personality and mood changes, and subcortical deficits like executive dysfunctions.

Laboratory Examination 

Structural neuroimaging showing vascular damage (depending upon etiology). They usually correspond to cognitive deficits

Course and Prognosis

Depending upon etiology, there may be large or strategic vascular events leading to a sudden onset, or there may be subcortical or small vessel changes leading to insidious onset and slow progression. There may be a static course, and sometimes it is progressive, often with fluctuating stepwise decline.

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Treatment of Vascular Dementia

There are two parts to treatment: primary prevention and symptomatic treatment.

Primary 

Includes controlling risk factors, including prevention from hypertension, avoiding hypotension in patients with stroke, controlling diabetes, and controlling hyperlipidemia. Patients with atrial fibrillation may be given anticoagulants. Patients with severe carotid stenosis may be treated with an endarterectomy or angioplasty. Patients with sleep apnea may be given positive pressure. Healthy life changes can be suggested, including a diet with less salt intake, avoiding stress and weight loss management, and smoking cessation.

Secondary

There are no FDA-approved drugs for vascular dementia. Cholinesterase inhibitors like donepezil, rivastigmine, and galantamine have shown improvement in patient's health in studies. Memantine is another less studied drug but has proven to have an important effect on cognitive functions.

Also read : How Do Different Patterns Of Injury Influence Psychiatric Disorders? 

FAQ’S

Q. What can be the prognosis for vascular dementia? 

Ans. Prognosis varies person to person; early diagnosis & early treatment can be the ideal way for better prognosis.

Q. How to prevent vascular dementia?

Ans. It can be prevented by maintaining a healthy lifestyle and maintaining BP and BMI with regular physical activity.

Hope you found this blog helpful for your Psychiatry residency Neurology and General Medicine preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs.