Can a Stroke Cause Dementia? Understanding the Possible Links

A stroke can cause a cluster of cognitive problems known as vascular dementia, which can be devastating for both patients and caregivers.

Stroke patients with vascular dementia can experience problems with their memory, reasoning, and judgment, among other symptoms. These changes can appear immediately after a stroke or gradually become worse over time.

This article will cover the causes and symptoms of vascular dementia after stroke and discuss some treatments that are available.

Causes and Types of Vascular Dementia After Stroke

Because a stroke impairs blood flow to the brain, it can lead to vascular dementia (although not all strokes have this outcome). It most often occurs after an ischemic stroke, which happens when an artery is blocked by a blood clot.

A person’s risk of post-stroke dementia increases with the number of strokes they experience. For example, one study that followed over 5,000 stroke victims found that the rate of vascular dementia was around 9 percent in those who had only suffered one stroke. In those who had experienced more than one stroke, however, the rate jumped to nearly 25 percent.  

There are three different types of vascular dementia that can occur after a stroke. These types affect different parts of the brain and are a result of different types of damage. They include:

• Strategic-infarct dementia. This type typically happens after someone has one large ischemic stroke, which damages a single, significant portion of the brain.
• Multi-infarct dementia. This is caused by a series of ministrokes, which cause small circles of damage throughout the brain.
• Subcortical dementia. This type is most often associated with lacunar stroke, a stroke that occurs in the small arteries deep within the brain.

These types of dementia all cause similar symptoms, however, which we will look at below.

Symptoms of Post-Stroke Dementia

The symptoms caused by vascular dementia can vary, depending on where the stroke occurred. The severity of the stroke will also influence the severity of the dementia. Some of the most common symptoms of post-stroke dementia include:

• Confusion
• Difficulty with concentration and following a conversation
• Language problems, such as aphasia
• Memory loss
• Problems with planning, problem-solving, and decision-making
• Restlessness and agitation
• Disorganized thoughts and actions
• Depression
• Rapid mood swings

Vascular dementia that is still in the early stages can also cause visual and spatial awareness problems.

In severe cases of vascular dementia, the symptoms can occur suddenly. However, with multi-infarct and subcortical dementia, cognitive changes occur more gradually. This can make the initial diagnosis challenging since the cause of the symptoms might not be immediately clear.

Can You Treat Dementia After Stroke?

Vascular dementia is unfortunately a progressive disease, which means the symptoms generally worsen over time.

However, it is still possible to slow the decline and improve your quality of life. You can do this by practicing cognitive rehabilitation exercises that engage the brain’s neuroplasticity. This can allow you to recover many cognitive skills after a stroke.

In addition, increasing blood flow to the brain can sometimes help improve cognitive function. A few ways to increase cerebral blood flow include:

• Try aerobic exercise. Aerobic exercise is one of the best ways to boost blood flow, which will bring more oxygen and nutrients to your brain cells and increase cognitive function.  Examples of aerobic exercise include activities such as brisk walks, swimming, and bicycling.
• Lower your blood pressure. High blood pressure constricts your arteries, making it more difficult for blood to flow up to the brain. Lowering your blood pressure causes the blood vessels to dilate, which can then allow more blood to reach the brain. Decreasing your blood pressure also reduces your risk of a second stroke.
• Stay hydrated. Blood is largely made up of water. Therefore, when you are dehydrated, your blood will thicken and have a harder time moving through your arteries. Staying hydrated then will thin the blood, increase blood flow, and reduce your risk of blood clots.

These tactics can all help treat the underlying cause of vascular dementia after stroke and reverse at least some of the symptoms.

Medications for Post-Stroke Dementia

While there are no medications designed specifically for vascular dementia, some drugs used on Alzheimer’s disease patients have shown promise. Alzheimer’s is a form of dementia, and thus shares many characteristics with vascular dementia.

One drug that may prove useful for stroke patients is memantine. Memantine, also known as Namenda, is used to treat the effects of Alzheimer’s disease and other forms of dementia. It does not cure these disorders, but it can slow progression and improve certain cognitive skills such as memory and awareness.

Memantine belongs to a class of medications called NMDA receptor antagonists. These drugs work by decreasing abnormal activity in the brain. Specifically, memantine blocks the action of glutamate, a chemical linked to dementia symptoms.

Some of the side effects commonly associated with memantine include:

• Dizziness
• Confusion
• Fainting
• Fatigue
• Seizures

However, memantine seems to have more effect in the early stages of vascular dementia, in that it slows down the progression. Therefore, if the patient’s dementia is advanced, this drug may not be as useful. Talk to your physician for more information on the benefits and risks of memantine for post-stroke dementia.

Caring for Someone with Vascular Dementia

Caring for a patient with vascular dementia can be a challenging experience. But there are ways to make things a little easier for both you and your loved one:

• Establish a routine. A calm environment can reduce worry and agitation, which in turn helps the person cope with their dementia. Establishing a daily routine that includes comfortable activities can help create this calm environment and take some pressure off you as well.
• Find a support group. Caring for someone with post-stroke dementia can be a full-time job, and this can lead to social isolation. Support groups put you in touch with people going through the same experiences and give you a network you can rely on for help and advice.
• Take time for yourself. To avoid caregiver burnout, it’s important to take time to care for your own needs. If possible, have another family member take over your caregiving duties for the day and allow yourself time to recharge.

Following these tips can help lighten the burden a little and make the caregiving process smoother.

Understanding the Connection Between Stroke and Dementia

In the end, there is an undeniable connection between stroke and dementia. While not every stroke patient will experience dementia, loss of blood flow to the brain can increase the person’s risk of cognitive decline.

However, by practicing cognitive stimulation and making certain lifestyle changes, patients can improve their symptoms and even slow vascular dementia’s progression.

Finally, always remember that even with post-stroke dementia, it is still possible to live a happy and fulfilling life. Although the road ahead might look difficult, it’s important to maintain hope.

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