Abstract
Objective: To compare the incremental prognostic value of pupillary reactivity as captured in the GCS-Pupils score (GCS-P) or added as separate variable to the Glasgow Coma Scale (GCS) in traumatic brain injury (TBI).Methods: We analyzed patients enrolled between 2014 and 2018 in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI, n=3521) and the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI, n=1439) cohorts. We used logistic regression to quantify the prognostic performances of GCS-P versus GCS according to Nagelkerke R2. Endpoints were mortality and unfavorable outcome (Glasgow Outcome Scale-Extended score 1-4) at 6 months after injury. We estimated 95% confidence intervals with bootstrap resampling to summarize the improvement in prognostic capability. Results: GCS as a linear score had a R2 of 24% (95% confidence interval [CI] 17-30) and 30% (95%CI 17-43) for mortality and 29% (95%CI 25-34) and 38% (95%CI 29-47) for unfavorable outcome in CENTER-TBI and TRACK-TBI respectively. In the meta-analysis, pupillary reactivity as a separate variable improved the R2 by an absolute value of 6% and 2% for mortality and unfavorable outcome (95%CI 4.0-7.7 and 1.2-3.0, respectively), with half the improvement captured in the GCS-P score (3%, 95%CI 2.1-3.3 and 1%, 95%CI 1-1.7, respectively). Conclusions: GCS-P has a stronger association with outcome after TBI than the GCS alone. However, for prognostic models, inclusion of GCS and pupillary reactivity as separate scores is preferable.
Competing Interest Statement
The authors have declared no competing interest.
Funding Statement
CENTER-TBI was supported by the European Union7th Framework Programme for Research (grant no. 602150; A.I.R.M.), Hannelore Kohl Stiftung (Germany), and OneMind (United States). Net-QuRe was supported by the Hersenstichting Nederland (Dutch Brain Foundation, grant no. ps2014.06). Dr. Korhonen reported research grants from the Finnish Cultural Foundation, Finnish Medical Foundation, and Orion Research Foundation outside the submitted work. Dr. Yue reported grants from the Neurosurgery Research and Education Foundationand Bagan Family Foundation Research Fellowship (award no. A139203, to the University of California, San Francisco) outside the submitted work. Dr. Maas reported grants from the European Union 7th Framework Programme for Research during the conduct of the study. Dr. Peul reported grants from European Committee Grant CENTER-TBI and grants from the Netherlands Brain Foundation during the conduct of the study. Dr. Posti reported funding from the Academy of Finland (grant no. 17379) and the Maire Taponen Foundation. Dr. van Essen reportedgrants from the European Union 7th Framework Programme for Research or CENTER-TBI and Hersenstichting Nederland (Dutch Brain Foundation) for Net-QuRe and the Niels Stensen Fellowship during the conduct of the study. Dr. Hutchinson is supported by the National Institute for Health and Care Research (Cambridge BRC, Brain Injury Medtech Co-operative, Global Health Research Group on Acquired Brain and Spine Injury, Senior Investigator Award) and the Royal College of Surgeons of England. The funders of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report.
Author Declarations
I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.
Yes
The details of the IRB/oversight body that provided approval or exemption for the research described are given below:
The CENTER-TBI study (EC grant 602150) has been conducted in accordance with all relevant laws of the EU if directly applicable or of direct effect and all relevant laws of the country where the Recruiting sites were located, including but not limited to, the relevant privacy and data protection laws and regulations (the Privacy Law), the relevant laws and regulations on the use of human materials, and all relevant guidance relating to clinical studies from time to time in force including, but not limited to, the ICH Harmonised Tripartite Guideline for Good Clinical Practice (CPMP/ICH/135/95) (ICH GCP) and the World Medical Association Declaration of Helsinki entitled Ethical Principles for Medical Research Involving Human Subjects Informed Consent by the patients and/or the legal representative/next of kin was obtained, accordingly to the local legislations, for all patients recruited in the Core Dataset of CENTER-TBI and documented in the e-CRF.Ethical approval was obtained for each recruiting sites. The list of sites, Ethical Committees, approval numbers and approval dates can be found on the CENTER-TBI and TRACK-TBI websites.
I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.
Yes
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I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.
Yes
Data Availability
All data produced in the present study are available upon reasonable request to the authors.
