Study Finds Major Traumatic Brain Injuries Increase Risk For Dementia

Traumatic brain injuries (TBI) can inflict various degrees of brain damage depending on the severity of the trauma. As per the Brain Trauma Foundation, a concussion is categorized as a mild TBI, while symptoms of a moderate TBI include lethargy and limited responses to visual stimuli. In severe TBI cases, a person may be in a comatose state for several hours.

The Centers for Disease Control and Prevention (CDC) reports that over 2 million people experience a TBI each year (via Brain Trauma Foundation). Over time, a TBI can impact one's physical and mental health. Speech difficulties, memory loss, vision issues, balance problems, and reduced language abilities are among some of the various side effects that can be experienced long-term (via University of Utah).

In addition, a new population-based study published in Neurology has revealed a link between major TBIs and increased dementia risk for patients later in life. Researchers delved into data dated from 1992 to 2012 for more than 31,000 patients in Finland between the ages of 25 and 64. As reported by HealthDay, 288 individuals had been hospitalized for a period of at least three days due to a major TBI — or brain bleeding, while 406 patients were hospitalized for up to 24 hours with a minor TBI — deemed by researchers as a concussion. None of the patients had developed dementia in the year following the injury.

Factors that influence dementia risk

Participants completed health surveys every five years over an average 16-year follow-up period, according to HealthDay. Study findings revealed that over time, 976 participants were found to have dementia. Those with major TBIs had the largest prevalence rates for dementia at 9%, versus 3% of those who had never had a TBI who developed dementia, and 2% of those with minor TBIs who developed dementia. "Approximately 1 in 10 people in our study who had major TBI did develop dementia," study co-author Dr. Rahul Raj summarizes to HealthDay.

However, researchers acknowledged age, sex, smoking, drinking, and inactivity as some of the biggest influencing factors (per HealthDay). The presence of such risk factors progressively decreased the connection between major TBI and dementia. Based on these findings, researchers emphasized the importance of addressing the risk factors that can be minimized through lifestyle changes, such as smoking or lack of physical movement.

Reinforcing this in a public statement, Dr. Rahul Raj said, ​​"Traumatic brain injury has been identified as a possible risk factor for dementia, and due to increasing numbers of people living with dementia, it is imperative to identify risk factors that might be modifiable to decrease the number of people who develop dementia in the future" (via HealthDay).