Data has been released on concussion research recently which reveals that: traumatic brain injury is associated with increased risk of developing both dementia and Alzheimer’s disease; women take longer to heal from a concussion; and a blood test is in the works which could change return to play protocols.

A significant long-term study has confirmed that the risk of dementia increases with the number and severity of traumatic brain injuries (TBIs) a person sustains. Conducted by Danish and American researchers, it followed 2. 8 million people over 36 years and found that those with TBIs were 24 per cent more likely to be diagnosed with dementia than those without.

“Individuals with a history of traumatic brain injury, including those with less severe injuries have an increased risk of developing dementia, even decades after the injury,” said Jesse Fann, Professor of psychiatry and behavioural sciences at the University of Washington School of Medicine, in Seattle, USA, who led the study.

“However, it’s important to emphasize that although the relative risk of dementia is increased after traumatic brain injury, the absolute risk increase is low. Our findings do not suggest that everyone who suffers a traumatic brain injury will go on to develop dementia in later life.”

It was also discovered that the younger a person was when they sustained a TBI, the more likely it was for them to develop dementia, when taking the time since their TBI into account.

Another study, comparing male and female athletes, found significant differences between the way men and women heal, in terms of post-concussion symptom severity and length of recovery. They measured peak symptom severity following concussion among the participants and the length of time to recovery, defined as the period of time between the injury and when they were cleared to return to full play.

Women, it turns out, take longer to recover from a concussion than men do. Interestingly, researchers found that the symptoms of women who take a hormonal contraceptive are lessened compared to those who do not.

A new blood test for assessing biomarkers associated with brain injury is being studied in Sweden. It is hoped the test will be able to indicate when a person who has sustained a concussion is able to resume sporting activities safely.

In their study, researchers compared concentrations of known biomarkers for concussion in blood samples taken directly after concussion and over a period of time. They took samples from 87 people who had sustained a concussion one, 12, 36 and 144 hours after the event. A final sample was taken when each person was determined fit to return to unrestricted activity by a doctor.

They found that the levels of the protein neurofilament light (NfL) had the clearest connection to the severity of concussion. “The strength of this study is that we longitudinally followed how these biomarkers are released and cleared from the blood. What we observed was that NfL was released within an hour after the concussion, and then it increased over time in players who had prolonged symptoms,” said lead author Dr. Pashtun Shahim.