Plasma Biomarkers, Brain Volume, and Cognitive Performance in Service Members and Veterans With mTBI: A LIMBIC-CENC...

Area of Science:

• Neuroscience
• Traumatic Brain Injury Research
• Biomarker Discovery

Background:

• Repetitive mild traumatic brain injury (mTBI) can lead to long-term cognitive deficits.
• Plasma biomarkers like GFAP, NfL, t-tau, and UCH-L1 are elevated acutely after mTBI.
• Few studies have examined these biomarkers in the chronic phase of mTBI.

Purpose of the Study:

• To investigate the association between plasma biomarkers, brain volume, and cognitive function in US service members and veterans with a history of mTBI.
• To determine if these associations differ based on the number of mTBIs sustained.

Main Methods:

• Cross-sectional analysis of data from the LIMBIC-CENC study (N=1160).
• Assessed plasma biomarkers (GFAP, NfL, t-tau, UCH-L1) using Quanterix SIMOA.
• Measured regional brain volume via MRI and cognitive performance using neuropsychological tests.
• Used regression models to examine biomarker associations with brain volume and cognition, moderated by mTBI history.

Main Results:

• Associations between biomarker levels, brain volume, and cognition varied by the number of mTBIs.
• In participants with 2 mTBIs, higher UCH-L1 correlated with smaller anterior cingulate volume.
• Higher t-tau, GFAP, and NfL were associated with poorer visual memory and executive function in those with 2 blast-related mTBIs.
• No significant biomarker-cognition associations were found in individuals with no history of mTBI.

Conclusions:

• Plasma biomarkers of neuronal injury and astrogliosis are associated with brain volume and cognitive performance in service members and veterans with mTBI.
• These associations appear to be dependent on the number of mTBIs sustained.
• Findings suggest potential utility of biomarkers in understanding chronic mTBI sequelae, though further research is needed.