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Chronic traumatic encephalopathy — confusion and controversies

Nature Reviews Neurology volume 15, pages 179–183 (2019)Cite this article

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Abstract

The term chronic traumatic encephalopathy (CTE) has recently entered public consciousness via media reports and even a Hollywood movie. However, in contrast to general impressions, the incidence of CTE is unknown, the clinical diagnostic criteria have not been agreed upon and the current neuropathological characterization of CTE is acknowledged as preliminary. Additionally, few studies have compared the pathologies of CTE with those of other neurodegenerative disorders or of age-matched controls. Consequently, disagreement continues about the neuropathological aspects that make CTE unique. Furthermore, CTE is widely considered to be a consequence of exposure to repeated head blows, but evidence suggests that a single moderate or severe traumatic brain injury can also induce progressive neuropathological changes. These unresolved aspects of CTE underlie disparate claims about its clinical and pathological features, leading to confusion among the public and health-care professionals alike.

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Fig. 1: Historical timeline of developments and the cumulative number of published cases of dementia pugilistica and CTE.
Fig. 2: Neuropathologies identified as being associated with neurodegeneration after TBI.

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Acknowledgements

The authors’ work is supported by funding from the US National Institute of Neurological Disorders and Stroke of the NIH under award numbers R01NS092398, R01NS094003 and R01NS038104.

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Authors and Affiliations

  1. Department of Neurosurgery, Penn Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA

    Douglas H. Smith & Victoria E. Johnson

  2. Department of Pathology and Laboratory Medicine, Institute on Aging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA

    John Q. Trojanowski

  3. Institute on Aging, University of Pennsylvania, Philadelphia, PA, USA

    John Q. Trojanowski

  4. Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA

    John Q. Trojanowski

  5. Department of Neuropathology, Queen Elizabeth University Hospital, Glasgow, UK

    William Stewart

  6. Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, UK

    William Stewart

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Correspondence to Douglas H. Smith.

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Smith, D.H., Johnson, V.E., Trojanowski, J.Q. et al. Chronic traumatic encephalopathy — confusion and controversies. Nat Rev Neurol 15, 179–183 (2019). https://doi.org/10.1038/s41582-018-0114-8

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