Objective: To compare differences using a metabolomics approach in older adults (≥55) with mild traumatic brain injury (mTBI) to control adults and to identify a signature profile related to functional outcome 3–6 months post-injury. Methods: We performed metabolomics analysis using LC-MS of untargeted aqueous metabolites on plasma samples taken from a parent prospective cohort study. Older adults with mTBI (n = 14) were purposively sampled to include participants with worsening (decrease in GOS-E of at least 1 level) and improved (increase in GOS-E of at least 1 level) outcomes from 3 to 6 months. The data were analyzed using PLS-DA with VIP scores, Random Forest, and spline fit between the different groups as a function of time for exposure on outcome. Results: Separation of comparisons were seen at 24 hours (negative ionization) and 6 months (positive ionization), revealing two metabolites of interest, phosphatidylcholine and phosphatidylethanolamine. Phosphatidylcholine levels were higher in those with mTBI compared to controls ( p < 0.05), while lower concentration of phosphatidylethanolamine was seen in those with mTBI compared to controls ( p < 0.05). Phosphatidylinositol-3,4,5-trisphosphate was significant in those with mTBI compared to controls (n = 10) based on improved (n = 6) versus worsened (n = 8) outcomes from 3 to 6 months. Conclusion: We identified plasma metabolites related to phospholipid metabolism in older adults following mTBI and associated with long-term functional outcome. These findings may underly pathological mechanisms of outcome differences in older adults who experience mTBI.
Impact of mild traumatic brain injury in the older adults on memory performance according to attentional load at encoding: Preliminary data
