Stroke, Brain Injury, and Dementia: is there a link?
Sep 17, 2020
Brain Injury and Dementia: Is There a Link?

Experiencing a brain injury is a huge, life-altering event. But even after the rehab, the outpatient therapy, and the lifestyle modifications, there can be another fear- will having a brain injury or a stroke lead to dementia in the future?

In this article

dementia definition

What is the link between brain injury and dementia?

Dementia is an umbrella term for a collection of cognitive and communicative deficits. Memory loss, executive functioning deficits, communication impairments and challenging behavior are the hallmarks of a dementia diagnosis. This can be extremely difficult for the person and their family, who have already endured a brain injury.

The link between brain injury and dementia is clear. Dementia affects 50 million people worldwide, and studies show that people who sustain an injury to the brain are twice as likely to develop dementia post-injury.

stroke and dementia can cause brain atrophy
Both brain injury and dementia can cause brain atrophy, disrupting brain cell connections and communication.

Why might a brain injury lead to dementia?

Why certain injury to the brain can cause dementia in older age is not always clear, though there are many working theories.

Alzheimer’s disease (AD) is the most common form of dementia, estimated to affect 5.5 million people in America today. AD accounts for between 60-80% of all cases of dementia, and is caused by an abnormal buildup of proteins in the brain, which interrupt and disrupt the messages being sent within the brain itself.

Some research shows that injury to the blood-brain-barrier, a membrane that selectively filters nutrients from the bloodstream into the brain, has a strong link to subsequent development of Alzheimer’s. The blood brain barrier can be damaged by hypoxia- oxygen deprivation that may be caused by a blockage- or by a traumatic brain injury.

Vascular dementia (VD), the second most commonly experienced dementia, is a step-wise decline in function as a result of several strokes. Strokes often cause temporary or long-lasting damage to the tissues in the brain, and the amount of recovery to these tissues may vary. When multiple strokes or brain injuries occur, the brain is not be able to heal fully, in time leading to VD.

Chronic Traumatic Encephalopathy (CTE), is a brain condition associated with multiple blows to the head and sometimes experienced by football players, boxers, or those with repeated falls. CTE has been linked with early onset of dementia, likely owing to some of the reasons above- non-healing injuries, and disruption to the BBB leading to accumulations of protein tangles in the brain.

dementia Alzheimer's brain cells
From left to right: a healthy neuron (brain cell), a neuron with amyloid plaque buildup as seen in Alzheimer's disease, and a dead neuron being digested by microglia cells.

Who is at risk of developing dementia after brain injury?

The incidence of those who develop dementia after a brain injury is estimated to be about two-fold of those in the general population. The risk factors that may make someone more susceptible to dementia include:

  • a Hemorrhagic versus Ischemic stroke (a bleed versus a blockage). This may be linked to the diffuse nature of a bleed, and the possible disruption of the blood-brain-barrier.
  • a stroke or brain injury occurring at a younger age; regardless of type, people who sustain an injury at a younger age are at an increased risk of developing dementia over the course of their lifespan.

Persons are also at the highest risk of dementia one year post-injury. After the one year mark, the increased risk persists across all types of brain injury/stroke, but at lower levels than before.

Dementia and Alzheimer's Disease

What can be done to reduce the risk of developing dementia?

Decreasing the risk of developing dementia when a brain injury or stroke has occurred is all about working on brain health and recovery. Keeping the brain healthy and allowing the damaged tissues to repair to their fullest extent may delay or even arrest later development of dementia.

The gold standard of dementia risk reduction includes physical activity, healthy living, cognitive engagement, and taking control of the reasons that a brain injury may have occurred in the first place.

Physical rehabilitation post-brain injury is essential to make sure that physical and medical issues are addressed. It is so important to be able to operate at the highest level possible, to live as healthfully as possible, even after a brain injury. Regular cardiovascular exercise will increase oxygenation in the body, which is necessary to help heal and improve brain health.

Eating more healthfully and avoiding overly fatty and processed foods will also improve brain health. Some research shows supplementation with vitamins, especially Vitamin K and Omega-3s, can help reduce risk of developing dementia.

Challenging your cognition, and maintaining engagement with cognitive tasks will also help to strengthen your brain. The process of learning may increase neural connections in the brain, essential for communication, memory, and other cognitive functions.

Meditation and mindfulness has been shown to increase grey matter in the brain, unequivocally improving cognition and brain health.

Resources for those at risk

Family conflict abounds in the diagnosis of dementia- seek out support groups through the Alzheimer's Association.

Looking for cognitive solutions for someone with a brain injury or stroke? Check out Neofect Cognition and the Neofect Smart Pegboard.


The best mental health care after a brain injury - Neofect’s 5 Stars
Mental Healthiness
The best mental health care after a brain injury - Neofect’s 5 Stars
Not only do many brain injury survivors struggle with physical changes, but they also suffer emotional changes. Here is the best mind health constellation to care your mental health.
7 Actionable stroke recovery daily living tips
Daily Living
7 Actionable stroke recovery daily living tips
Has your lifestyle changed after a stroke? We’ll let you know what you should do in your daily living and 7 actionable tips for your successful stroke recovery.
How to regain hand grasp and function
How to regain hand grasp and function
The ability to do these simple tasks reduces dependency on others, improves potential for employment and enhances quality of life.
Using the Neofect Smart Glove to Maximize Constraint-Induced Movement Therapy
Constraint Induced Movement Therapy (CIMT) is used to treat people with Hemiplegia by constraining or restricting movement of the non-affected hand to force a person to use their affected hand.
Hemiplegia vs. HemiparesisHemiplegia vs. Hemiparesis
Hemiplegia and hemiparesis could seem very similar because they sometimes have the same underlying symptoms. However, they have different meanings.
What  does  a  drop  foot  brace  do?
Foot drop
What Does A Foot Drop Brace Do?
Are you contemplating to buy a drop foot brace? Here is the check list you need to consider before buying one.