Predictive Blood Biomarkers of Targeted Intervention for Chronic Mental Health Symptoms following Traumatic Brain Injury

The purpose of this study was to assess the performance of predictive blood biomarkers for responsiveness to targeted treatments for chronic psychological issues years after traumatic brain injury (TBI). Targeted Evaluation Action and Monitoring of TBI was a prospective 6-month interventional trial of participants with chronic TBI sequelae (<i>n</i> = 95). Plasma biomarkers were analyzed pre-intervention: glial fibrillary acidic protein (GFAP), tau, hyperphosphorylated tau Thr231 (p-Tau), von Willebrand factor (vWF), brain lipid-binding protein (BLBP), ubiquitin C-terminal hydrolase-L1 (UCH-L1), vascular endothelial growth factor-a (VEGFa), and claudin-5 (CLDN5). Clinical outcomes included the Post-Traumatic Stress Disorder (PTSD) Checklist for DSM-5 (PCL-5) and Brief Symptom Inventory-18 (BSI-18). Regression models were built for change in PCL5/BSI-18. Biomarkers and covariates were included. Two models were built to identify responders (improved beyond the minimum clinically important difference). The model to predict change in PCL5 (<i>R</i>²=0.64; <i>p</i> < 0.001) included vWF (<i>p</i> = 0.032), BLBP (<i>p</i> = 0.001), tau (<i>p</i> = 0.002), VEGFa (<i>p</i> = 0.015), female sex (<i>p</i> = 0.06), and military status (<i>p</i> = 0.014). The model to predict change in BSI-18 (<i>R</i>²=0.42; <i>p</i> = 0.003) included vWF (<i>p</i> = 0.042), VEGFa (<i>p</i> = 0.09), BLBP (<i>p</i> = 0.01), CLDN5 (<i>p</i> < 0.001), female sex (<i>p</i> = 0.012), and military status (<i>p</i> = 0.004) as predictors. The model to differentiate participants who improved for PCL5 (<i>R</i>²=0.68; <i>p</i> < 0.001; AUC = 0.93) included vWF (<i>p</i> = 0.02), VEGFa (<i>p</i> = 0.008), and BLBP (<i>p</i> = 0.006). The model to differentiate participants who improved for BSI-18 (<i>R</i>²=0.25; <i>p</i> = 0.04; AUC = 0.75) included UCH-L1 (<i>p</i> = 0.03), GFAP (<i>p</i> = 0.06), and vWF (<i>p</i> = 0.03). Combinations of pre-intervention blood biomarkers were able to differentiate responders from nonresponders in both post-traumatic stress and overall psychological health domains.