October 3, 2023

J Neurotrauma. 2023 Sep 12. doi: 10.1089/neu.2023.0207. Online ahead of print.


Neurofilament light (NF-L) is an axonal protein that has shown promise as a traumatic brain injury (TBI) biomarker. Serum NF-L shows a rather slow rise after injury, peaking after 1-2 weeks, although some studies suggest that it may remain elevated for months after TBI. The aim of this study was to examine if plasma NF-L levels several months after the injury correlate with functional outcome in patients who have sustained TBIs of variable initial severity. In this prospective study on 178 patients with TBI and 40 orthopaedic injury controls, we measured plasma NF-L levels in blood samples taken at the follow-up appointment on average nine months after injury. Patients with TBI were divided into two groups [mild (mTBI) vs. moderate to severe (mo/sTBI)] according to the severity of injury assessed with the Glasgow Coma Scale upon admission. Recovery and functional outcome were assessed using the Extended Glasgow Outcome Scale (GOSE). Higher levels of NF-L at the follow-up correlated with worse outcome in patients with moderate to severe TBI (Spearman’s rho = -0.18; p < 0.001). In addition, in CT-positive mTBI group, the levels of NF-L were significantly lower in patients with GOSE 7-8 (median 18.14; IQR 9.82, 32.15) when compared with patients with GOSE <7 (median 73.87; IQR 32.17, 110.54; p = 0.002). In patients with mTBI, late NF-L levels do not seem to provide clinical benefit for late-stage assessment, but in patients with initially mo/sTBI, persistently elevated NF-L levels are associated with worse outcome after TBI and may reflect ongoing brain injury. Keywords: traumatic brain injury, outcome, biomarker, Neurofilament light, NF-L.

PMID:37698882 | DOI:10.1089/neu.2023.0207