Overview
Figure 1. Summary of vascular dementia
Vascular dementia affects the brain’s ability to retain and access memories. It is the second most common form of dementia following Alzheimer’s disease. Arteriosclerosis causes vascular dementia by hardening arteries throughout the body – when arteries harden in the brain, it affects the organ’s ability to stay healthy [1]. At the time when Dr. Alois Alzheimer published his first report on Alzheimer’s dementia in 1906, arteriosclerosis was considered to be an entirely separate disease [2]. Since a series of small strokes in the brain can cause vascular dementia, it was originally called multi-infarct dementia [3].
It wasn’t until the mid-1970’s that vascular dementia was recognized as a unique disease caused by hypertension and poor vascular health. It’s the second-most common form of dementia following Alzheimer’s disease, and affects up to 1.5% of American adults. Vascular dementia is slightly more common in eastern countries such as Japan. If you’ve had a stroke in the past, you’re up to 9 times more likely to have memory loss. Likewise, people with hypertension have an 80% chance of developing it [1].
Symptoms
Vascular dementia progresses through a series of steps. Some people may improve for a time after each stroke, making the disease even more difficult to diagnose and treat. The severity of cognitive impairment differs for each individual. Acute, sudden onset of memory loss is equally common as subacute progression. Physical symptoms include weakening on one half of the body, problems retaining balance, and changes in gait or reflexes. Cognitive markers can help physicians differentiate between Alzheimer’s disease and vascular dementia. For example, those with vascular dementia tend to have an easier time with free memory recall but more problems with speech than Alzheimer’s patients [3].
Causes and risk factors
Figure 2. Blood supply to the brain
Cardiovascular health is the biggest predictor of an individual’s propensity to developing vascular cognitive impairment [3]. This means that hypertension, high cholesterol, and diabetes mellitus put individuals at a higher risk of memory loss. It is possible to have Alzheimer’s disease and develop vascular dementia as a result of it. These cases are identified by the presence of cerebral amyloid angiopathy, a condition in which the accumulation of beta amyloid plaques in arterial walls causes circulatory damage [4]. This is evidenced by the higher rate of brain bleeds and strokes in people with Alzheimer’s disease. Some neuroanatomical areas are more likely to be affected than others. One of these is the anterior cerebral artery which supplies oxygen to the frontal and upper parietal lobes of the brain. The hippocampus and thalamus may be affected, which impairs the consolidation of new memories and learning experiences.
Reduce your risk factors
– Reduce your caffeine intake: Reducing your caffeine intake will help your body retain B-complex vitamins. B-complexes such as vitamin B12 and vitamin B6 help your brain metabolize energy from food as efficiently as possible
– Supplement your diet with B vitamins: As mentioned above, B vitamin complexes are important for metabolism and energy. Homocysteine is a compound that is generated in our body during the metabolism of the amino acid methionine to cysteine. Some research suggests that elevated homocysteine levels are associated with cognitive decline. You can minimize your homocysteine levels by taking B vitamin complexes or eating food that contains them.
– Maintain physical and social activity: This is pretty self-explanatory. The more social interaction you have, the less likely you are to suffer from dementia or depression as you age.
– Increase your antioxidant intake: By eating the recommended number of servings for fruits and vegetables each day, you’ll be consuming antioxidants which help protect your cellular structures from free radicals. A free radical is a highly reactive portion of a molecule – that is to say it can create unnatural bonds with organic compounds. When these compounds fuse with a free radical, there is chemical disruption in the body. Blueberries, cranberries, blackberries, pitted fruits, and tree nuts are all good sources of antioxidants. Flavonoids and polyphenols are associated with maintained memory function. In addition to fruits and cruciferous vegetables, you can find these compounds in tea, chocolate, and red wine. Experts recommend about 6 servings of fruits and vegetables per day to optimize antioxidant intake.
Diagnosis and treatment
If you suspect that you or a loved one is at risk for developing vascular dementia, there are steps you can take to address your risk factors. The most obvious approach is to maintain your cardiovascular health using regular aerobic exercise and lowering your cholesterol intake. After addressing your risk factors, your physician and neurologist can examine several diagnostic criteria to determine whether this disease is affecting your cognition. The DSM-IV and Hachinski ischemic scores are among the most common guidelines [3]. After computing your overall change in affect and ischemic score, specific biomarkers will be measured to determine whether a nutritional deficiency is partially to blame for memory loss. Commonly used biomarkers include blood counts, liver function panels, thyroid hormone panels, syphilis serum, vitamin B12, and folate.
There are currently no medications indicated specifically for vascular dementia. Some patients elect to try memantine and cholinesterase inhibitors, which are used for Alzheimer’s disease, but result in little improvement. Being aware of your risk factors and taking steps to keep your circulatory system healthy remains the best course of action to prevent vascular dementia.
References
[1] Vascular Dementia. (2020, March 26).
[2] Alois Alzheimer (1864 – 1915), Manuel B. Graeber, University Department of Neuropathology, Imperial College London and Hammersmith Hospitals Trust, London, UK.
[3] Vascular dementia. (2020, May 29).
[4] Cerebral amyloid angiopathy. (2020, May 20).