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Originally Posted On: https://geriatricacademy.com/cerebral-small-vessel-disease/

 

Cerebral small vessel disease is a very common condition among the elderly that affects the small vessels in your brain.

The changes in your vascular system due to CSVD can cause abnormalities in your brain. Such abnormalities can be seen using neurological imaging and may include findings such as:

• Lacunar Stroke – Lacunar infarcts are strokes that happen when one or more of the brain’s small arteries become blocked. This reduces blood flow and oxygen transport to the brain.
• White matter hyperintensities (WMH), also known as white matter changes. These will be discussed later in the article but occur when a certain brain region does not receive enough blood and oxygen.
• Cerebral (brain) microbleed. This occurs when the small blood vessels in the brain bleed.
• Brain atrophy. This phenomenon refers to the loss of neurons in the brain, causing the brain to get smaller in volume. Brain atrophy is associated with cognitive decline and dementia [1].

 

CSVD contributes to 20 to 30 percent of ischemic stroke, hemorrhagic stroke, and cerebral microbleeds.

The resulting brain damage is responsible for 45 percent of dementia cases in later life.

CSVD affects almost all older adults over 90 years of age and can cause the cognitive and functional decline seen in many elderly individuals.

The brain and vascular changes seen in CSVD are also associated with neurodegenerative diseases such as mild cognitive impairment and Alzheimer’s disease [1,2,3].

 

What causes cerebral small vessel disease?

 

Experts do not fully understand the mechanisms underlying CSVD, and there are several potential causes.

The two most common causes of CSVD include atherosclerosis-associated and amyloid-associated CSVD, which causes a reduction in cerebral blood flow, and cerebrovascular disease [2].

 

Atherosclerosis

 

Atherosclerosis affects your arteries. The arteries are blood vessels that carry blood from your heart to the rest of your body.

In arteriosclerosis, the artery walls become thick because of scarring and inflammation.

Cerebral small vascular atherosclerosis refers to the thickening of very small arteries (less than 50 micrometers in diameter) in the brain. Your arteries may also twist, get stretched out, and have reduced flexibility.

 

The heart and body need to constantly be pumping blood to deliver oxygen to your brain cells and other tissues.

When blood vessels are too thick and impaired, it is harder for the body to pump blood around the body.

For example, it can affect blood flow to the brain, leading to vascular cognitive impairment.

One study found that in patients with Alzheimer’s and Binswanger’s diseases (two types of dementia), blood flow was reduced by 25 percent compared with normal patients [1].

 

Amyloid changes

 

Amyloid is an abnormal protein that can build up to form deposits in the body’s organs and tissues.

In amyloid-related CVSD, amyloid builds up in the walls of small or medium-sized arteries.

The accumulation of amyloid affects the blood-brain barrier (BBB). The BBB is a barrier that controls what moves from the blood into the brain.

Amyloid deposits compromise the integrity of the BBB, causing leakage and blood vessel abnormalities. This can cause damage to the brain.

 

Amyloid in the blood vessels is almost always present in elderly individuals with dementia, specifically Alzheimer’s disease.

Additionally, these amyloid abnormalities occur in 64 to 85 percent of elderly individuals with normal cognitive function [1,2].

Amyloid positron emission tomography, or PET scans, can identify and quantify abnormal amyloid plaque buildup in the brain (cerebral amyloid angiopathy).

What are the risk factors for cerebral small vessel disease?

 

While CSVD can occur with age, it can be worsened with conditions such as hypertension and diabetes. Likewise, risk factors for CSVD include:

• Hypertension
• Diabetes mellitus
• Heart attack
• Smoking
• Atrial fibrillation (abnormal heart rhythm)
• Age
• Obesity
• Cholesterol problems
• Chronic kidney disease
• Infection
• Blood disorders
• Certain hereditary diseases [1]

What are the symptoms of CSVD?

 

The symptoms of CSVD will vary depending on what caused the condition and the part of your brain that is affected. Some symptoms may include:

 

• Stroke – CSVD contributes to 25 percent of strokes. Additionally, having CSVD can double your chances of having another stroke.
• Decline in cognitive function and/or dementia. CSVD contributes to roughly 45 percent of dementia cases. Cognitive problems associated with CSVD can present as poor memory and attention, slower information processing, and trouble with recall.
• Walking difficulties. If you experience problems with movement due to CSVD, you may have a slower walking rate, shorter stride, and wider stance than normal. Gait issues with CSVD should not be confused with Parkinson’s disease. Both conditions have similar symptoms but are different. Movement problems with CSVD differ in that you may experience urinary problems, rigidity, falls, and dementia. CSVD symptoms will not include tremors and will have a poor response to levodopa, a Parkinson’s medication.
• Psychiatric problems. CSVD can cause you to become agitated, anxious, depressed, or irritable. You may also experience hallucinations, changes to your appetite, and trouble sleeping.
• Mood and behavior problems You may also experience changes in your emotions, such as feelings of depression or disinterest.
• Troubles with urinating. Symptoms can include difficulty urinating, frequently urinating, urinating in the middle of the night, or feeling the urge to urinate.
• Other signs. Other symptoms of CSVD may include vertigo (dizziness and/or trouble balancing), ringing in the ear, and hearing problems [1,3].

 

How do doctors diagnose CSVD?

Your doctor can diagnose CSVD using magnetic resonance imaging (MRI). Using an MRI scan, your provider can evaluate your brain for abnormalities. An important finding includes a “white matter hyperintensity” (WMH).

Your brain consists of two types of tissues: white matter and grey matter. White matter is important when it comes to CSVD.

White matter consists of the nerve fibers in the brain. White matter is very susceptible to small blood vessel changes that cause low blood flow and oxygen transport to the brain.

Your doctor can see changes in your brain’s white matter on MRI scans.

When an area of your brain does not receive enough blood and oxygen, it becomes damaged, forming a WMH.

This appears as a bright white area on an MRI. Your doctor may also be able to see other abnormalities on an MRI, such as a stroke or microbleed [3].

Another type of scan that they can order is an amyloid PET scan (see below).

That said, I do not recommend getting brain imaging simply because you suspect that you have CSVD.

This is because you will likely see some changes in your brain if you are old enough.

If your brain imaging does show changes, the main culprit may not necessarily be CSVD. Many other problems can mimic it, including dementia,

One study showed that 95% of study participants 60-90 years old showed signs of having CSVD with brain imaging [6].

Just like in the management of dementia, confirmation of the problem in brain imaging does not change the treatment options for CSVD.

The most important aspect of slowing the progression of CSVD is to carefully manage the underlying medical problems, such as high blood pressure, diabetes, high cholesterol, and other cardiovascular risk factors.

How can you treat or prevent Cerebral Small Vessel Disease?

 

How you prevent and treat CSVD will depend on your individual risk factors, medical history, MRI findings, and symptoms. Your options for management are detailed below.

 

Reduction of cardiovascular risk factors:

Lowering your blood pressure

 

Blood pressure is a critical risk factor for CSVD. Thankfully, you can effectively treat your blood pressure with medication.

One study found that individuals on antihypertensive (blood pressure lowering) medications had slower progression of WMH [3].

 

Lowering blood pressure can also reduce your risk of having a stroke.

Another study demonstrated that lowering your systolic blood pressure to less than 120 mmHg decreased stroke incidence by 41% compared with higher targets [1].

 

Since this type of damage to the brain happens over a long time, it is very important to control your blood pressure by taking your medications and testing your blood pressure at home, exactly as instructed by your doctor. Thus, preventing this type of damage is entirely within your control.

 

Antiplatelet therapy

 

 

Antiplatelet medications are medications that prevent a blood clot from forming.

Multiple trials have demonstrated that aspirin, an antiplatelet, lessens your chance of having another stroke by 30 percent.

Other options include dual therapy with aspirin and another agent, such as clopidogrel.

While effective, dual therapy may increase your risk of bleeding. Not everyone is a candidate for antiplatelet therapy.

Your doctor will determine your eligibility based on your current medical conditions and after weighing benefits against risks.

It is very important that you disclose to your doctor everything that you are taking, including supplements, herbals, and OTC agents, no matter how seemingly safe they may seem.

 

Thrombolysis

Thrombolysis is the process of dissolving a blood clot, which can increase blood flow and oxygen circulation throughout your body.

A blood clot in your brain is what causes a stroke.

Therefore, if you have a stroke, the doctor may administer what is known as recombinant tissue plasminogen activator (r-tPA). R-tPA is a thrombolytic agent that can dissolve a blood clot.

 

One study demonstrated that those that had a stroke and received r-tPA had better neurologic outcomes than those who did not. However, having WMH may increase your risk of bleeding with r-tPA.

 

Thrombolysis has other clinical considerations and, therefore, may only be indicated in certain patients. Only your doctor or neurologist is qualified to make these decisions.

 

Statins

Statins are used to lower cholesterol. In those with WMH, statin treatment has been shown to lower your risk of stroke, cognitive decline, and WMH progression.

Particularly, atorvastatin 80 mg has demonstrated efficacy in preventing stroke. Statins can also improve the function of the BBB [3].

 

Lifestyle changes

You can also reduce your risk of CSVD and other diseases through lifestyle changes.

Regular physical activity, a healthy diet, and avoiding certain behaviors can prevent certain symptoms of CSVD.

Behavioral changes such as stopping smoking, limiting alcohol intake, and limiting dietary sodium can prevent the worsening of brain abnormalities and related complications.

 

Sleep disturbances can also affect your brain health. Poor nighttime sleep has been shown to decrease brain volume, and increased daytime sleep is associated with MRI abnormalities [4].

 

Should I get tested to see if I have CSVD?

While some patients with CSVD will demonstrate symptoms such as stroke or cognitive decline, others may not have any symptoms at all.

Your doctor may incidentally find signs of CSVD when looking at neuroimaging, such as white matter hyperintensity in an MRI.

When you have CSVD but do not have symptoms, this is known as being “asymptomatic” or having “silent” CSVD.

Currently, there is no standard for identifying individuals with CSVD that are asymptomatic.

Therefore, it is unknown whether treating asymptomatic CSVD is necessary or beneficial.

Prevention is Key!

Once damage to brain tissue has happened, it cannot be reversed.

However, all of us have the ability to prevent damage by controlling the modifiable risk factors that contribute to the development of CSVD.

How do we do this? By controlling other chronic medical conditions you have that may cause or worsen CSVD.

These include managing high blood pressure, high cholesterol, and stroke risk. If you have any of these conditions, your doctor may start you on one of the therapies detailed above [4,5].

As I have mentioned above, you can control the outcome by doing your part and listening to your doctor’s advice, and taking all of your medications exactly as prescribed.

This includes taking daily blood pressure and blood sugar readings and recording them in a journal or log, to be shown to your doctor at your next follow-up visit.

Your doctor will then have a very clear idea of whether your prescribed medications are working or if the doses need to be adjusted for better control.

This therapeutic alliance between you, your doctor, and your pharmacist who dispenses your medications will ensure the best preventative medicine for you.

 

References

1. Li Q, Yang Y, Reis C, Tao T, Li W, Li X, Zhang JH. Cerebral Small Vessel Disease. Cell Transplant. 2018 Dec;27(12):1711-1722. doi: 10.1177/0963689718795148. Epub 2018 Sep 25. PMID: 30251566; PMCID: PMC6300773.
2. Litak J, Mazurek M, Kulesza B, Szmygin P, Litak J, Kamieniak P, Grochowski C. Cerebral Small Vessel Disease. Int J Mol Sci. 2020 Dec 20;21(24):9729. doi: 10.3390/ijms21249729. PMID: 33419271; PMCID: PMC7766314.
3. Cannistraro RJ, Badi M, Eidelman BH, Dickson DW, Middlebrooks EH, Meschia JF. CNS small vessel disease: A clinical review. Neurology. 2019 Jun 11;92(24):1146-1156. doi: 10.1212/WNL.0000000000007654. Epub 2019 May 29. PMID: 31142635; PMCID: PMC6598791.
4. https://journals.lww.com/cmj/Fulltext/2021/01200/Clinical_management_of_cerebral_small_vessel.1.aspx
5. Das AS, Regenhardt RW, Vernooij MW, Blacker D, Charidimou A, Viswanathan A. Asymptomatic Cerebral Small Vessel Disease: Insights from Population-Based Studies. J Stroke. 2019 May;21(2):121-138. doi: 10.5853/jos.2018.03608. Epub 2019 Apr 17. PMID: 30991799; PMCID: PMC6549070.
6. de Leeuw FE, de Groot JC, Achten E, Oudkerk M, Ramos LM, Heijboer R, Hofman A, Jolles J, van Gijn J, Breteler MM. Prevalence of cerebral white matter lesions in elderly people: a population based magnetic resonance imaging study. The Rotterdam Scan Study. J Neurol Neurosurg Psychiatry. 2001 Jan;70(1):9-14. doi: 10.1136/jnnp.70.1.9. PMID: 11118240; PMCID: PMC1763449.