White Matter Hyperintensity in Patients with Mild Traumatic Brain Injury Correlates with Higher Coated-Platelet Levels (P3.323)

Objective: To examine if increased coated-platelet synthesis is associated with the presence of white matter hyperintensity (WMH) in patients with mild traumatic brain injury (mTBI). Background: Coated-platelets are highly procoagulant platelets observed upon dual-agonist stimulation with collagen and thrombin. In normal controls, coated-platelet levels represent 30[percnt] of the entire platelet population. In previously published studies, prompted by data showing an increased risk for ischemic stroke following TBI, we found that coated-platelet levels are persistently elevated in mTBI patients several years post injury compared to controls, and higher levels correlate with an increased number of injuries. We now investigate if the presence of WMH in these patients is related to coated-platelet measurements. Methods: Coated-platelet levels were determined in 103 veterans with combat-related mTBI that underwent brain MRI. The presence of WMH was determined by a neuroradiologist blinded to the study protocol. Correlations were calculated between the presence of WMH and coated-platelet levels, age, gender, race/ethnicity, smoking, hypertension, diabetes, number of injuries, and medications that may influence coated-platelet levels (antiplatelets, statins and SSRIs). Significance was set at 0.05. Results : Mean coated-platelet levels were 43.1±14.7 (mean±SD), the time elapsed since the last injury was 6.0±2.6 years and mean age was 37.2±8.5 years. WNH was present in 20 patients (19.4[percnt]). Significant correlations were found between WMH and age (P=0.019), coated-platelet levels (P=0.006), and use of statins (P=0.05). Logistic regression analysis showed that only age (P=0.03) and coated-platelet levels (P=0.004) were associated with the presence of WMH. No significant change in coated-platelet levels was noted at 6-12 months from initial measurements (P=0.9). Conclusions: These preliminary results suggest that increased platelet procoagulant potential and age are significant predictors for the presence of WMH in mTBI, many years after the injury. Additional studies aimed at determining the long-term impact of these findings is warranted. Disclosure: Dr. Prodan has received research support from the Veterans Affairs Office. Dr. Vincent has nothing to disclose. Dr. Guthery has nothing to disclose. Dr. Mathews has nothing to disclose. Dr. Sadler has nothing to disclose. Dr. Dale has nothing to disclose.