Magnetic resonance imaging (MRI) has shown that even mild traumatic brain injuries (TBI) have far-reaching effects on brain health, researchers report.

The results could lead to better patient care, wrote a team led by Dr. Audrey Low of the University of Cambridge in the UK. They were published on August 15 in JAMA network opened.

“(Our study found that) detectable changes in brain imaging and clinical features were associated with advanced, even mild, TBIs in the general population,” the group noted. “The potential contribution of vascular injury to TBI-related neurodegeneration offers promising opportunities for identifying potential targets. The findings underscore the need to reduce TBIs through early intervention and prevention in both clinical care and policymaking.”

TBIs are a risk factor for dementia, Low’s group explained. However, although vascular changes have been documented in the clinical literature in people who have suffered a TBI – particularly in contact sport athletes – the association between TBI-related brain imaging changes and clinical outcomes in a general, cognitively healthy population has not been fully understood.

The researchers investigated possible associations between neuroimaging changes in midlife traumatic brain injury and clinical features in 617 healthy adults aged 40 to 59 years using a study that included data from the PREVENT dementia program between 2014 and 2020. The team analyzed data between January 2023 and April 2024 and determined lifetime history of traumatic brain injury using the Brain Injury Screening Questionnaire (BISQ).

All study participants underwent a 3-Tesla MRI scan. Researchers identified any cerebral microbleeds or other symptoms of cerebral microangiopathy (such as white matter hyperintensities, lacunae, or perivascular spaces) and assessed brain health by tracking participants’ cognitive abilities, sleep, depression, gait, and cardiovascular disease risk using the following tools: Computerized Assessment of Information Processing (COGNITO), Pittsburgh Sleep Quality Index, the Center for Epidemiologic Studies Depression Scale, clinical interviews, and the Framingham Risk Score (the latter based on age, systolic blood pressure, use of antihypertensive medications, current smoking, diabetes, and cholesterol).

Overall, the team found:

• One third of the study participants reported at least one traumatic brain injury resulting in loss of consciousness.
• Patients with a previous TBI were more likely to be current smokers (odds ratio 2.48).
• Cerebral microbleeds were detected in one of six participants. TBI was associated with a higher number of microbleeds (β = 0.10, p = 0.03), but not with other indicators of small vessel disease, including increased white matter hyperintensities.
• In the case of memory deficits, TBI was found to have a greater influence on the development of memory disorders than cardiovascular diseases such as diabetes or high blood pressure. However, it was not the main cause of attention deficits.

According to the authors, the study results underscore the need to further investigate the effects of traumatic brain injury on brain health.

“(We report that) a history of TBI, even mild TBI, was associated with detectable clinical and neuroimaging changes as early as midlife,” they concluded. “These findings highlight the potential consequences of TBI on brain health and provide a possible pathological mechanism driving TBI-related neurodegeneration… (Our research highlights) potential intervention targets for dementia prevention in patients with TBI and opportunities for future research.”

You can find the complete study here.