Prior head injury linked to higher risk for cognitive change over 30 years

Key takeaways:

• Researchers examined cognition in 11,677 individuals, with 2,110 having a recorded prior head injury.
• Those who sustained a head injury were at significantly increased risk for cognitive change after 30 years.

PHILADELPHIA — Individuals who sustained at least one head injury saw an increased risk for developing cognitive issues over a 30-year period compared to those who did not, according to a poster presentation.

“It’s well-established that head injury or traumatic brain injury is associated with dementia risk,” Andrea L.C. Schneider, MD, PhD, assistant professor in the department of neurology, University of Pennsylvania Perelman School of Medicine, told Healio at the American Neurological Association annual meeting. “Knowing the patterns of cognitive change over time that get you to that dementia threshold, is important.”

Schneider and colleagues sought to examine the association between head injury and cognitive change over a 30-year period in older adults from the Atherosclerosis Risk in Communities (ARIC) study, an ongoing prospective cohort initially recruited from locations in the United States in the late 1980s.

Their analysis included 11,677 individuals (mean age 57.2 years; 58.1% female) from the ARIC study, 2,110 of whom had a head injury confirmed by self-report as well as ICD 9 and 10 diagnostic codes (mean age 59.0 years; 64.8% female), along with 9,567 individuals without prior head injury (mean age 57.4 years; 56.7% female). Cognitive testing for the entire study population was conducted at five study visits during the following intervals: 1990 to 1992; 1996 to 1998; 2011 to 2013; 2016 to 2017; and 2018 to 2019, with scores taken from each visit combined into a factor score of global cognition.

Researchers employed linear mixed effects models with random intercept, time slope and unstructured covariance matrix to estimate associations of head injury with changes in cognition per decade, while adjusting for age at baseline, sex, race, education, veteran status and various health factors.

According to results, a significant change was found per decade in those with head injury (-0.045; 95% CI, -0.082 to -0.007) compared with those without head injury (-0.105; 95% CI, -0.163 to -0.048), a difference of 136.9% after 3 decades. Additionally, the percentage of difference between the groups reached as high as 149.7% for those whose head injuries were mild and 154.1% for those who sustained at least two head injuries compared with those who did not.

“Traumatic brain injury-related pathology persists after the acute phase, interacts with normal aging and causes cognitive decline that happens at an accelerated rate,” Schneider told Healio.