The effects of concussion were apparent in some individuals four years after they suffered their brain injury, a New Zealand study has found.
Auckland University of Technology researcher Alice Theadom and her colleagues set out to determine if there were long-term effects from concussion.
The study team, writing in the peer-reviewed journal PLOS ONE, noted there was increasing evidence that some people can experience persistent symptoms for up to a year after a concussion. However, there were few studies that explored longer-term impacts.
The study used 232 people aged 16 or older who had experienced a concussion four years ago. They had been identified in an earlier concussion study.
This group did not simply include those who sought medical treatment after suffering their injury. For self-reported cases, details of the accident were obtained and reviewed by a diagnostic team of neurologists, clinicians and neuropsychologists to determine study eligibility.
Those who were dazed or confused after their incident, had lost consciousness for 30 minutes or less, and/or had not been able to remember what happened during the accident were considered eligible.
The study participants underwent several tests to find any evidence of post-concussion symptoms, anxiety, depression, and sleep problems. Questions also explored their community involvement.
The results were compared to those from a control group of 232 age and sex-matched individuals.
Those who had suffered concussion experienced significantly increased self-reported cognitive symptoms four years after their injury when compared to the control group. These included forgetfulness, poor concentration and taking longer to think.
The concussion group reported significantly poorer community participation across productivity, social relations and getting out and about compared to controls.
There were no differences between the groups’ physical or emotional symptoms, indicating that any issues with these resolved over time. However, cognitive symptoms can become persistent and concussion can impact longer-term community participation, the study team said.
The results obtained in the concussion group four years after the injuries were little different to those obtained a year after, indicating their problems were chronic.
Early intervention was needed, the researchers said, to reduce the longer-term impact of cognitive symptoms, and new approaches were needed to encourage participation.
“The persistence of cognitive symptoms four years post-injury suggests that cognitive symptoms which fail to resolve in the acute phase post-injury are likely to become chronic, and impact participation without intervention,” the researchers said.
They said their work was the first study to identify that adults experienced significantly greater community participation difficulties than controls four years after their injury.
Their findings complimented previous research which highlighted the impact of concussion on work productivity four years after the injury.
“The current findings highlight that the impact of mild traumatic brain injury [concussion] extends beyond paid employment and also affects wider community participation.”
The authors said one of the strengths of the study was the inclusion of participants who attended hospital post-injury in addition to those who received medical attention in the community, or did not seek medical treatment at all.
The findings found that those seeking medical attention were at greatest risk of poorer long-term outcome, which showed it was an important point of contact where interventions could help to improve long-term outcome.
The study team comprised Theadom, Nicola Starkey, Suzanne Barker-Collo , Kelly Jones, Shanthi Ameratunga and Valery Feigin, variously affiliated with the Auckland University of Technology, the University of Waikato, and the University of Auckland.
Theadom A, Starkey N, Barker-Collo S, Jones K, Ameratunga S, Feigin V, et al. (2018) Population-based cohort study of the impacts of mild traumatic brain injury in adults four years post-injury. PLoS ONE 13(1): e0191655. https://doi.org/10.1371/journal.pone.0191655