Point-of-Care Platform Blood Biomarker Testing of Glial Fibrillary Acidic Protein versus S100 Calcium-Binding Protein B for Prediction of Traumatic Brain Injuries: A Transforming Research and Clinical Knowledge in Traumatic Brain Injury Study
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.
Characteristics of Biostatistics, Epidemiology, and Research Design Programs in Institutions With Clinical and Translational Science Awards
Purpose To learn the size, composition, and scholarly output of biostatistics, epidemiology, and research design (BERD) units in U.S. academic health centers (AHCs). Method Each year for four years, the authors surveyed all BERD units in U.S. AHCs that were members of the Clinical and Translational Science Award (CTSA) Consortium. In 2010, 46 BERD units were surveyed; in 2011, 55; in 2012, 60; and in 2013, 61. Results Response rates to the 2010, 2011, 2012, and 2013 surveys were 93.5%, 98.2%, 98.3%, and 86.9%, respectively. Overall, the size of BERD units ranged from 3 to 86 individuals. The median FTE in BERD units remained similar and ranged from 3.0 to 3.5 FTEs over the years. BERD units reported more availability of doctoral-level biostatisticians than doctoral-level epidemiologists. In 2011, 2012, and 2013, more than a third of BERD units provided consulting support on 101 to 200 projects. A majority of BERD units reported that between 25% and 75% (in 2011) and 31% to 70% (in 2012) of their consulting was to junior investigators. More than two-thirds of BERD units reported their contributions to the submission of 20 or more non-BERD grant or contract applications annually. Nearly half of BERD units reported 1 to 10 manuscripts submitted annually with a BERD practitioner as the first or corresponding author. Conclusions The findings regarding BERD units provide a benchmark against which to compare BERD resources and may be particularly useful for institutions planning to develop new units to support programs such as the CTSA.
Assessing Statistical Competencies in Clinical and Translational Science Education: One Size Does Not Fit All
Background and Purpose— Early hematoma expansion in spontaneous intracerebral hemorrhage (ICH) is associated with worse clinical outcome. We hypothesized that hemodynamic parameters are associated with the increase in hematoma volume owing to their relationship to blood vessel wall stresses. Methods— We performed a post hoc analysis of clinical and computed tomography (CT) data from patients enrolled in a prospective observational study of ICH patients presenting within 3 hours from symptom onset. Hematoma volumes were measured at hospital arrival and at 1 and 20 hours from presentation. Blood pressure and heart rate, recorded at 19 time points between presentation and 20 hours, were used to derive hemodynamic variables. Multivariable logistic-regression models were constructed to assess the relation between hemodynamic parameters and hematoma growth, adjusted for clinical covariates. Results— From the original study, 98 patients underwent baseline and 1-hour CT scans; of these, 65 had 20-hour CT scans. Substantial hematoma growth was observed in 28% within the first hour. Of the 65 patients not undergoing surgery within 20 hours, 37% experienced hematoma growth by 20 hours. Neither baseline or peak hemodynamic parameters nor changes in hemodynamic parameters were significantly associated with hematoma growth at either 1 or 20 hours. Conclusions— We found no blood pressure or heart rate parameters, individually or in combination, that were associated with hematoma growth. Our data suggest the influence of hemodynamic parameters on vessel wall stress to be an unlikely target for intervention in reducing the risk of early hematoma growth in ICH.