The links between concussion and minor head injury and long-term cognitive issues have again been highlighted through new research.
As well as impacts including sleep disturbances, mood disorders and headache, a study found that 13.5 per cent of people who had been diagnosed a year ago with concussion, or mild traumatic brain injury, were found to have “poor cognitive outcome.”
This included cognitive impairment, defined as performing at less than the ninth percentile in testing of areas like memory and processing speed (10.1 per cent of patients); and/or cognitive decline, demonstrated by a meaningful drop in test scores from two weeks after the injury to months later (3.4 per cent of patients).
By contrast, just 4.5 per cent of participants in the UC San Francisco study without concussions subsequently had poor cognitive outcomes.
Of this percentage, 3.3 per cent had cognitive impairment and 1.2 per cent had both cognitive impairment and cognitive decline.
Researchers tracked the outcomes of 656 patients who met the criteria for concussion after presenting at level one trauma centres.
The patients, whose average age was 40, were compared with 156 demographically matched participants who had not had concussions.
Both groups had been enrolled in the TRACK-TBI study, a brain injury research initiative headed by principal investigator Dr Geoffrey Manley, of UCSF and Zuckerberg San Francisco General Hospital.
“We found that patients who experienced good cognitive outcomes following concussion sustained less severe injury, based on the scoring system of the head CT,” said senior author Dr Raquel Gardner, of the UCSF Department of Neurology and the UCSF Weill Institute for Neurosciences.
Approximately one in three concussions was caused by being in a car during a collision. These patients were more likely to have a poor one-year cognitive outcome (43 per cent) than a good one (34 per cent).
Underlying conditions like diabetes, depression, anxiety and developmental disability were also associated with a significantly higher likelihood of having a poor one-year cognitive outcome.
The study shows that the cognitive impacts of concussion may be more common than previously thought, said Dr Gardner, adding that the results, “highlight the need to better understand the mechanisms underlying poor cognitive outcome, even after relatively mild brain injuries, to improve recovery.”
“Traumatic brain injury is highly heterogenous and the cognitive issues resulting from it are heterogenous, ranging from direct damage to parts of the brain subserving cognitive function, to secondary effects of concussion-related depression, anxiety, post-traumatic stress disorder and sleep problems,” said Dr Gardner.
“A thorough evaluation is necessary to unravel treatable contributors and refer to the best rehabilitation program to optimise recovery.”
