By Colleen Kienbaum, RN-BSN

Brain Injury Awareness Month is here and the perfect time to learn more about how amazing yet vulnerable our brains are to impact and injury. According to the Brain Injury Association of America, one out of every 60 Americans lives with a traumatic brain injury-related disability. Let’s explore the various types of brain injuries and what researchers are saying about their possible link with increased risk for Alzheimer’s disease and dementia later in life.

What is a traumatic brain injury? 

A traumatic brain injury is any injury in which the brain sustains a level of trauma with or without loss of consciousness. Traumatic brain injuries are currently classified into three categories: mild, moderate and severe. The most common causes of traumatic brain injury are falls where the head is impacted and motor vehicle accidents. Mild brain injuries can be concussions and may involve no loss of consciousness or a loss of consciousness that lasts 30 minutes or less. A loss of consciousness anywhere from 30 minutes up to 24 hours after a brain injury is considered a moderate brain injury. A severe brain injury is one that leads to a loss of consciousness for 24 hours or longer.

Traumatic brain injury and dementia risk

Research has shown that traumatic brain injuries can increase risks for memory impairment in addition to cognitive decline. While the known occurrence of head injury is an important factor when discussing risk, how or why it can lead to increased risk for dementia and Alzheimer’s disease is not well known. New research is beginning to shed some light on the underlying science of why head injuries can have lasting impacts on brain health.

Mild cognitive impairment is considered an early-stage risk factor for Alzheimer’s disease. With Alzheimer’s disease, amyloid plaques and tau tangles are seen in the brain and ultimately lead to the clinical diagnosis of Alzheimer’s. Many studies have demonstrated that traumatic brain injury, including head injury, is a risk factor for dementia and Alzheimer’s disease in addition to other neurodegenerative conditions. Researchers for the Alzheimer’s Disease Neuroimaging Initiative found that tau levels were elevated in people with a history of head injury, especially when it accompanied a loss of consciousness. They concluded that increased tau levels resulting from a head injury could be a likely cause of cognitive decline and dementia risk later in life.

Repetitive head injuries and dementia risk

Besides traumatic brain injuries, there is also concern over repetitive head injuries and how they impact a person’s risk for cognitive decline over time. Repetitive head injuries are those often seen in professional football players or boxers. In an article published in Alzheimer’s & Dementia^®: Diagnosis, Assessment & Disease Monitoring, one study found that later-life plasma total tau levels were elevated in former NFL players. 

Elevated tau levels are also significant for increased risk of chronic traumatic encephalopathy, a neurodegenerative disease involving cognitive, behavioral and mood deficits and sometimes motor function issues. Chronic traumatic encephalopathy is uniquely diagnosed in those who have experienced repetitive and chronic head impacts over a period of time. More research is needed to confirm plasma diagnosis for chronic traumatic encephalopathy, but it is a step in the right direction to help in early identification, and therefore, earlier implementation of treatment options.

Prevention is the best protection

In order to help protect the brain, it is best to take preventative measures whenever possible. Take proven measures when applicable: buckle your seat belt when driving or riding in a vehicle, use a helmet when skateboarding or rollerblading and limit activities that involve multiple impacts to the head. Take proactive steps to love your brain, as prevention is the best option to ensure long-lasting brain health.

If you or someone you love experiences a head injury or any symptoms of a traumatic brain injury, it is important to seek medical attention. Brain injuries can vary widely in symptoms and severity, and it is always best to remain alert to changes following an impact. Trauma to the brain can occur quickly, even when it seems that symptoms are rapidly improving. If someone experiences a loss of consciousness, seizure activity or nausea and vomiting following impact to the head, it can be a sign of traumatic brain injury and being evaluated by trained medical personnel quickly is very important. Also, seek emergency medical care if a person falls from a height greater than 3 feet or sustains injury following ejection from a motor vehicle.

In conclusion, there are no definitive studies that show a single head injury will increase a person’s risk of dementia or Alzheimer’s disease diagnosis. Traumatic brain injuries, as well as repetitive impacts to the head, can be serious and have long-lasting consequences. The brain is very sensitive to injury, and while short-term effects may be nonexistent, over time they can increase a person’s risk for cognitive decline, Alzheimer’s disease and other types of dementia. Click here for more information and a list of resources related to brain injury and dementia.

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Colleen Kienbaum, RN-BSN, is passionate about writing on various health care topics from a nurse’s perspective. She has worked in several nursing specialties including emergency medicine, cardiac care and perioperative services for the past eight years. Currently, she holds CPAN and CAPA certifications and enjoys the dynamic role nurses play in today’s health care. Colleen is also a military spouse and mother who enjoys traveling and exploring new places with her family.