Review article
Systematic Review of the Prognosis After Mild Traumatic Brain Injury in Adults: Cognitive, Psychiatric, and Mortality Outcomes: Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis

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Abstract

Objective

To synthesize the best available evidence on objective outcomes after adult mild traumatic brain injury (MTBI).

Data Sources

MEDLINE and other databases were searched (2001–2012) for studies related to MTBI. Inclusion criteria included published, peer-reviewed articles in English and other languages. References were also identified from the bibliographies of eligible articles.

Study Selection

Randomized controlled trials and cohort and case-control studies were selected according to predefined criteria. Studies had to have a minimum of 30 MTBI cases and assess objective outcomes in adults.

Data Extraction

Eligible studies were critically appraised using a modification of the Scottish Intercollegiate Guidelines Network (SIGN) criteria. Two reviewers independently reviewed each study and extracted data from accepted articles into evidence tables.

Data Synthesis

Evidence was synthesized qualitatively according to modified SIGN criteria, and studies were categorized as exploratory or confirmatory based on the strength of their design and evidence. After 77,914 records were screened, 299 were found to be relevant and critically reviewed, and 101 were deemed scientifically admissible. Of these, 21 studies that were related to the objective outcomes form the basis of this review. Most evidence indicates the presence of cognitive deficits in the first 2 weeks post-MTBI, and some evidence suggests that complete recovery may take 6 months or a year. A small number of studies indicate that MTBI increases the risk of psychiatric illnesses and suicide.

Conclusions

Early cognitive deficits are common, and complete recovery may be prolonged. Conclusions about mortality post-MTBI are limited. This review has implications for expected recovery after MTBI and MTBI-related health sequelae. Well-designed confirmatory studies are needed to understand the medium- to long-term consequences of MTBI and to further evaluate the effect of prior MTBI and injury severity on recovery.

Section snippets

Methods

The protocol registration, case definition, literature search, critical review strategy, and data synthesis are outlined in detail elsewhere7 and in this issue.8 Briefly, the electronic databases MEDLINE, PsycINFO, Embase, CINAHL, and SPORTDiscus were systematically searched from 2001 to 2012. Reference lists of all systematic reviews and meta-analyses related to MTBI and all articles meeting the eligibility criteria were checked to ensure that relevant studies were not missed.

Articles were

Results

Out of 77,914 records screened for our entire review, 2170 full-text articles were assessed for eligibility, 299 were critically reviewed, and 101 (ie, 34%) were deemed scientifically admissible (fig 1). This article presents the 21 accepted studies (all were published in English) reporting findings on course and prognostic factors associated with neuropsychological findings, psychiatric disorders, suicide subsequent to MTBI, mortality outcomes, and other objective outcomes. These studies form

Discussion

This review update of the course of recovery and prognostic factors expands on the WHO Collaborating Centre Task Force 2004 review and best evidence synthesis of MTBI.4 Overall, the evidence from both the current review and the 2004 review is consistent in suggesting the presence of initial cognitive deficits in adults after MTBI, although the nature of these deficits varies across studies, and there are no confirmatory (phase III) studies. This conclusion is consistent with the systematic

Conclusions

There is a substantial body of evidence suggesting that MTBI-related neuropsychological deficits are present during the first 2 weeks after an MTBI. However, there is less agreement in the literature on when these deficits resolve, and there is evidence from studies conducted over the last decade that some objectively measured cognitive deficits can last upward of 6 months. The certainty of this conclusion is limited by the small number of good quality studies examining this issue. There is

Acknowledgments

We thank the other members of the International Collaboration on MTBI Prognosis (ICoMP): Jean-Luc af Geijerstam, MD, PhD, Eleanor Boyle, PhD, Victor G. Coronado, MD, MPH, James Donovan, DC, Alison K. Godbolt, MBChB, MD, Ryan Hung, MD, MSc, Michelle Keightley, PhD, Alvin Li, BHSc, Connie Marras, MD, PhD, Peter Rumney, MD, and Britt-Marie Stålnacke, MD, PhD. We also thank Panos Lambiris, MSc, Information Scientist, University Health Network, for assisting in developing, testing, and updating the

References (35)

  • L.J. Carroll et al.

    Prognosis for mild traumatic brain injury: results of the WHO Collaborating Centre Task Force on Mild Traumatic Brain Injury

    J Rehabil Med

    (2004)
  • L.J. Carroll et al.

    WHO Collaborating Centre Task Force on Mild Traumatic Brain Injury. Methodological issues and research recommendations for mild traumatic brain injury: the WHO Collaborating Centre Task Force on Mild Traumatic Brain Injury

    J Rehabil Med

    (2004)
  • Iverson GL, Gaetz M. Practical considerations for interpreting change following brain injury. In: Lovell MR, Echemendia...
  • C. Cancelliere et al.

    Protocol for a systematic review of prognosis after mild traumatic brain injury: an update of the WHO Collaborating Centre Task Force findings

    Syst Rev

    (2012)

  • Report to Congress on mild traumatic brain injury in the United States: steps to prevent a serious public health problem

    (2003)
  • Healthcare Improvement Scotland. SIGN 1993-2013. Available at: http://www.sign.ac.uk/. Accessed November...
  • P. Côté et al.

    A systematic review of the prognosis of acute whiplash and a new conceptual framework to synthesize the literature

    Spine

    (2001)

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    Supported by the Ontario Neurotrauma Foundation (grant no. 2010-ABI-MTBIWHO-871).

    The funder was not involved in the design or preparation of the study protocol, or in the management of the project, analysis or interpretation of data, or the preparation of the final article.

    No commercial party having a direct financial interest in the results of the research supporting this article has conferred or will confer a benefit on the authors or on any organization with which the authors are associated.

    The findings and conclusions in this research are those of the authors alone and do not necessarily represent the official views or policies of the Centers for Disease Control and Prevention or any agency of the United States government. Inclusion of individuals, programs, or organizations in this article does not constitute endorsement by the United States government.

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