Neurofilament Light as a Biomarker in Traumatic Brain Injury

In the article “Neurofilament Light as a Biomarker in Traumatic Brain Injury,” by P. Shahim et al.,¹ some of the data regarding the cohort of Swedish athletes that are available in the paper's Supplementary Appendix should have been expanded upon and placed in the text of the main paper. As cited in the Supplementary Appendix, 45 of the cases reported in figures 2, B and C were previously included in the 2018 P. Shahim et al.² article “Neurofilament light and tau as blood biomarkers for sports-related concussion,” published in Neurology. These cases include all the preseason patients (n = 28), and 17 of the 45 individuals in acute concussion (AC) cohort. While some of the cases are the same, with the exception of the 17 individuals in the AC cohort, the data reported in the figures is novel and represents the results of separate lab analyses, using an updated in-house assay in 2019. Readers interested in knowing more about our Swedish cohort may refer to the 4 papers cited in the manuscript and Supplementary Appendix, as well as:

• Shahim P, Tegner Y, Marklund N, et al. Astroglial activation and amyloid metabolism in human repetitive concussion. Neurology 2017 Mar 10. doi: 10.1212/WNL.0000000000003816.

• Siman R, Shahim P, Tegner Y, Blennow K, Zetterberg H, Smith DH. Serum SNTF Increases in Concussed Professional Ice Hockey Players and Relates to the Severity of Postconcussion Symptoms. J Neurotrauma Sep 1 2015;32(17):1294–1300.

• Shahim P, Linemann T, Inekci D, et al. Serum tau fragments predict return to play in concussed professional ice hockey players. J Neurotrauma Jan 26 2015.

• Shahim P, Tegner Y, Wilson DH, et al. Blood biomarkers for brain injury in concussed professional ice hockey players. JAMA Neurology Jun 2014;71(6):684–692.