Yue, John K.

Abstract Older adults have the highest incidence of traumatic brain injury globally. Accurate blood-based biomarkers are needed to assist with diagnosis of patients across the spectrum of age and time post-injury. Several reports have suggested lower accuracy for blood-based biomarkers in older adults, and there is a paucity of data beyond day-1 post-injury. Our aims were to investigate age-related differences in diagnostic accuracy and 2-week evolution of four leading candidate blood-based traumatic brain injury biomarkers—plasma glial fibrillary acidic protein, ubiquitin carboxy-terminal hydrolase L1, S100 calcium binding protein B and neuron-specific enolase—among participants in the 18-site prospective cohort study Transforming Research And Clinical Knowledge in Traumatic Brain Injury. Day-1 biomarker data were available for 2602 participants including 2151 patients with traumatic brain injury, 242 orthopedic trauma controls and 209 healthy controls. Participants were stratified into 3 age categories (young: 17–39 years, middle-aged: 40–64 years, older: 65–90 years). We investigated age-stratified biomarker levels and biomarker discriminative abilities across three diagnostic groups: head CT-positive/negative; traumatic brain injury/orthopedic controls; and traumatic brain injury/healthy controls. The difference in day-1 glial fibrillary acidic protein, ubiquitin carboxy-terminal hydrolase L1 and neuron-specific enolase levels across most diagnostic groups was significantly smaller for older versus younger adults, resulting in a narrower range within which a traumatic brain injury diagnosis may be discriminated in older adults. Despite this, day-1 glial fibrillary acidic protein had good to excellent performance across all age-categories for discriminating all three diagnostic groups (area under the curve 0.84–0.96; lower limit of 95% confidence intervals all >0.78). Day-1 S100 calcium-binding protein B and ubiquitin carboxy-terminal hydrolase L1 showed good discrimination of CT-positive versus negative only among adults under age 40 years within 6 hours of injury. Longitudinal blood-based biomarker data were available for 522 hospitalized patients with traumatic brain injury and 24 hospitalized orthopaedic controls. Glial fibrillary acidic protein levels maintained good to excellent discrimination across diagnostic groups until day 3 post-injury irrespective of age, until day 5 post-injury among middle-aged or younger patients and until week 2 post-injury among young patients only. In conclusion, the blood-based glial fibrillary acidic protein assay tested here has good to excellent performance across all age-categories for discriminating key traumatic brain injury diagnostic groups to at least 3 days post-injury in this trauma centre cohort. The addition of a blood-based diagnostic to the evaluation of traumatic brain injury, including geriatric traumatic brain injury, has potential to streamline diagnosis.

Glial fibrillary acidic protein (GFAP) is cleared by the Food and Drug Administration (FDA) to determine need for head computed tomography (CT) within 12 h after mild traumatic brain injury (TBI) (Glasgow Coma Score [GCS] 13–15); S100 calcium-binding protein B (S100B) serves this function in Europe. This phase 1 biomarker cohort analysis of the multi-center, observational Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study compares GFAP's diagnostic performance, measured on a rapid point-of-care platform, against protein S100B to predict intracranial abnormalities on CT within 24 h post-injury across the spectrum of TBI (GCS 3–15). Head CT scan performed in TBI subjects and blood was collected for all consenting subjects presenting to 18 United States level 1 trauma centers. Plasma was analyzed on a point-of-care device prototype assay for GFAP and serum was analyzed for S100B. In 1359 patients with TBI (GCS 3–15), mean (standard deviation [SD]) age = 40.1 (17.0) years; 68% were male. Plasma GFAP levels were significantly higher in CT+ TBI subjects (median = 1358 pg/mL, interquartile range [IQR]: 472–3803) than in CT- TBI subjects (median = 116 pg/mL, IQR: 26–397) or orthopedic trauma controls ( n = 122; median = 13 pg/mL, IQR: 7–20), p < 0.001. Serum S100B levels were likewise higher in CT+ TBI subjects (median = 0.17 μg/L, IQR: 0.09–0.38) than in CT- TBI subjects (median = 0.10 μg/L, IQR: 0.06–0.18), p < 0.001. Receiver operating characteristic curves were generated for prediction of intracranial injury on admission CT scan; area under the curve (AUC) for GFAP was significantly higher than for S100B in the same cohort (GFAP AUC – 0.85, 95% confidence interval [CI] 0.83–0.87; S100B AUC – 0.67, 95% CI 0.64-0.70; p < 0.001). GFAP, measured on a point-of-care platform prototype assay, has high discriminative ability to predict intracranial abnormalities on CT scan in patients with TBI across the full injury spectrum of GCS 3–15 through 24 h post-injury. GFAP substantially outperforms S100B.

Abstract INTRODUCTION Glioblastoma has a poor prognosis, further complicated by postoperative seizures. We analyzed various factors associated with postoperative seizures in glioblastoma. METHODS Retrospective chart review of 932 patients who underwent craniotomy for glioblastoma (777=83.4% newly diagnosed; 155=16.6% recurrent) at our institution (2002–2014). Postoperative seizures were defined as those occurring within 14 days of surgery. RESULTS Our cohort consisted of 49.9% (n=465) males with mean age of 55.8 (range 9–91) years. In total, 69 (7.4%) had postoperative seizures with mean time from surgery to seizure of 3.1 days (IQR=1–4). Of 536 patients (57.5%) receiving seizure prophylaxis, those treated with Keppra were more likely to have postoperative seizures compared to those on Dilantin (10.9% vs 5.0%; p=0.022). Primary tumor patients were less likely to seize postoperatively compared to recurrent tumor patients (9.7% vs 19%; p=0.016). Patients presenting with seizure as chief complaint (12.1% vs 5.1%; p=0.025) and those with >20% of Chromosome 10 deletion were more likely to have seizures postoperatively (12.4% vs 6.1%; p=0.0029). Risk factors for postop seizures for newly-diagnosed patients included subtotal resection versus gross total resection (28.0% vs 7.1%; p=0.022). Risk factors for postop seizures for recurrent patients were >5% EGFR amplification (23.5% vs 5.8%; p=0.0021) and hyponatremia within mean 2.5 days (IQR 0–1) after surgery (20.8% vs 7.1%; p=0.035). CONCLUSION We identified several risk factors for postoperative seizures in glioblastoma patients, most of which were clinical (seizure as chief complaint, the antiepileptic chosen for prophylaxis, and extent of resection), while some were molecular and linked to genes whose products have demonstrated links to epileptogeneicity (Chromosome 10, EGFR). These findings may assist physicians in detecting glioblastoma patients that are at higher risk for postoperative seizures and in providing prophylaxis to reduce morbidity.

OBJECTIVEFollowing traumatic brain injury (TBI), midline shift of the brain at the level of the septum pellucidum is often caused by unilateral space-occupying lesions and is associated with increased intracranial pressure and worsened morbidity and mortality. While outcome has been studied in this population, the recovery trajectory has not been reported in a large cohort of patients with TBI. The authors sought to utilize the Citicoline Brain Injury Treatment (COBRIT) trial to analyze patient recovery over time depending on degree of midline shift at presentation.METHODSPatient data from the COBRIT trial were stratified into 4 groups of midline shift, and outcome measures were analyzed at 30, 90, and 180 days postinjury. A recovery trajectory analysis was performed identifying patients with outcome measures at all 3 time points to analyze the degree of recovery based on midline shift at presentation.RESULTSThere were 892, 1169, and 895 patients with adequate outcome data at 30, 90, and 180 days, respectively. Rates of favorable outcome (Glasgow Outcome Scale–Extended [GOS-E] scores 4–8) at 6 months postinjury were 87% for patients with no midline shift, 79% for patients with 1–5 mm of shift, 64% for patients with 6–10 mm of shift, and 47% for patients with > 10 mm of shift. The mean improvement from unfavorable outcome (GOS-E scores 2 and 3) to favorable outcome (GOS-E scores 4–8) from 1 month to 6 months in all groups was 20% (range 4%–29%). The mean GOS-E score for patients in the 6- to 10-mm group crossed from unfavorable outcome (GOS-E scores 2 and 3) into favorable outcome (GOS-E scores 4–8) at 90 days, and the mean GOS-E of patients in the > 10-mm group nearly reached the threshold of favorable outcome by 180 days postinjury.CONCLUSIONSIn this secondary analysis of the Phase 3 COBRIT trial, TBI patients with less than 10 mm of midline shift on admission head CT had significantly improved functional outcomes through 180 days after injury compared with those with greater than 10 mm of midline shift. Of note, nearly 50% of patients with > 10 mm of midline shift achieved a favorable outcome (GOS-E score 4–8) by 6 months postinjury.