What is Vascular Dementia?
The term vascular dementia stems from 'vascular' referring to the body's blood circulation system, and 'dementia', a broad term encompassing neurodegenerative diseases associated with cognitive decline. Therefore, vascular dementia is dementia as a result of changes to the brain's blood and oxygen supply.
What Causes Vascular Dementia?
Changes to the brain's vasculature can occur because of one of the following causes:
Cerebrovascular disease
Cerebrovascular causes of vascular dementia can include stroke, small vessel disease, or multi-infarct dementia, also known as Binswanger's disease. Binswanger disease is dementia caused by multiple consequent strokes to deep brain areas, accumulating damage to brain tissue. [1, 2]
Hypertension
Also known as high blood pressure, which increases the strain on blood vessels throughout the body. The small diameter of the capillaries in the brain makes them particularly vulnerable to damage by high blood pressure [1]. Despite this well-known association, recent Randomised Control Trials found a link between cognitive decline and low blood pressure, bringing into question what the ideal blood pressure is in older people [3].
Atherosclerosis
Atherosclerosis refers to narrowing the blood vessel walls by forming a sclerotic plaque. When this plaque is disrupted by increased blood pressure, it attracts clotting factors, increasing the change of clot formation. Atherosclerosis can consequently stop blood flow at the site of the plaque or in a narrower blood vessel if the plaque breaks off. Furthermore, atherosclerosis produces neuroinflammation and microRNA changes, which can further increase cognitive decline [4].
Diabetes
Diabetes is a dysfunction of glucose uptake into cells, which leaves high glucose levels in the bloodstream. This can lead to any of the conditions mentioned above, as excess glucose in the blood is toxic to the blood vessel walls [5].
Cerebral Amyloid Angiopathy
In cerebral amyloid Angiopathy, amyloid protein plaques deposit in the blood vessel walls of vascular supply to the basal ganglia, damaging their integrity. This can lead to progressive leaking of blood into the brain, which in severe cases may resemble a stroke [6].
What are the Symptoms of Vascular Dementia?
The symptoms of vascular dementia are very similar to other dementias. The difference between vascular dementia and Alzheimer's Disease is that symptom onset is very gradual in Alzheimer's disease, but symptoms of vascular dementia usually increase in steps. These steps relate to progressive damage to the oxygen supply in affected brain areas.
The symptoms include: [1]
- Difficulty performing daily tasks, such as driving, shopping, or navigation
- Motor difficulties
- Memory problems
- Misplacing items
- Changes to sleep patterns and sleep quality
- Personality changes
- Loss of interest in things and activities one used to enjoy (e.g. reading, cooking, socialising)
How is Vascular Dementia Diagnosed?
ICD-10 Criteria for Vascular Dementia
Vascular dementia can be diagnosed according to the ICD-10 criteria, where the ICD-10 code for vascular dementia is F01 [7]. Vascular dementia ICD-10 criteria include vascular damage to a considerable section of the patient's brain. Symptoms can onset rapidly or gradually; therefore, it is essential to keep a lookout for the above-mentioned vascular dementia symptoms, particularly in high-risk groups. Patients' most common symptoms are reduced cognitive abilities, such as thinking, decision-making, or planning activities.
The first step in diagnosing vascular dementia is an MRI or CT brain scan.
Although vascular dementia itself cannot be identified from a brain scan, the vascular dementia MRI scan will be able to pick up vascular changes, damaged microregions, or previous silent strokes (strokes that affected a small part of the brain in which the patient did not have any symptoms). Therefore, structural damage due to cerebrovascular factors is a critical discriminator in diagnosing Vascular dementia as opposed to frontotemporal dementia, Alzheimer's disease, or mild cognitive impairment. Changes to blood vessels can also be measured using magnetic resonance angiography. [7]
A patient can have more than one type of dementia, in which case they will receive a diagnosis of "Mixed Dementia".
What are the Treatments for Vascular Dementia?
Primary Prevention of Vascular dementia
At the moment, there are few approved treatments to treat Vascular Dementia. By reducing the risk factors, primary prevention is the first-line recommended strategy to tackle vascular dementia [1]. This includes:
- Reduction in fat intake
- Reducing blood pressure or blood thinning medication
- Increase in physical activity, where possible
- Reducing alcohol intake
In fact, it has been shown that smoking, diabetes, hypertension, and physical inactivity sum to 10% of vascular dementia risk, with additional lifestyle factor modifications accounting for a further 30% risk reduction. This is very high in a multifactorial disease such as vascular dementia. [8]
Vascular Dementia Treatments
Secondary management and cognitive rehabilitation can help restore some cognitive ability [8].
Acetylcholine esterase inhibitors, for example, can be used to increase the amount of acetylcholine in the synapse, increase blood flow in the brain and thereby increase neural function in damaged areas [9]. Although these drugs are primarily approved for Alzheimer's Disease, some studies have found significant cognitive improvements in vascular dementia patients as well.
Memantine, a type of glutamatergic-activating drug, has also been associated with increased cognitive function across several subscales in vascular dementia [10].
New treatments for vascular dementia can also include supplementation of folic acid, vitamin B12 or calcium blockers. Ongoing studies are looking at their specific efficacy and functional improvements [11].
Alongside pharmacological therapies, rehabilitation strategies, such as Attention Training, have some efficacy for improving cognitive function. In specific patients, these exercises strengthened brain connections and improved specific aspects of brain function, such as attention and language [11].
Summary: Recognising Symptoms of Vascular Dementia and Getting Treatment for Vascular Dementia
Understanding vascular dementia requires a comprehensive overview of its intricate causes, symptoms, and potential treatments. While primary prevention through lifestyle modifications offers a significant risk reduction, the limited approved vascular dementia treatments underscore the urgency for continued research. Empowering individuals and caregivers with information about vascular dementia symptoms and vascular dementia diagnosis is critical to facing the challenges posed by vascular dementia. Stay informed, embrace a heart-healthy lifestyle, and advocate for ongoing research to show new pathways towards improving outcomes in vascular dementia.