Science News: Prediagnostic Neurofilament Light Chain Levels in Amyotrophic Lateral Sclerosis

Submitted by: Niranjan N. Singh, MD, DM
Edited by: Sarah Chen, MD

Bjornevik K, O'Reilly EJ, Molsberry S, et al. Prediagnostic neurofilament light chain levels in amyotrophic lateral sclerosis. Neurology. 2021 Aug 11;97(15):e1466–74. doi: 10.1212/WNL.0000000000012632
 
Summary: This study focused on pre-diagnostic biomarkers in amyotrophic lateral sclerosis (ALS). This matched case-control study included 84 individuals who developed ALS during follow-up and had available plasma samples prior to disease diagnosis. For each ALS case, a randomly matched control was selected. Neurofilament (NfL) in these pre-diagnostic plasma samples were measured and adjusted for body mass index, smoking physical activity, etc. Higher NfL levels were found to be associated with a high ALS risk within 5 years of ALS diagnosis. There were 21 Nfl-associated metabolites collected and measured, but none of them showed any significant correlation.
 
Comments: Over last decade, multiple studies looking for biomarkers in ALS have evaluated NfL levels in both CSF and blood. Most widely studied neurofilaments are light chain and phosphorylated heavy chain. NfL levels reflect neuronal injury and has potential value in ALS and other neurological disorders.
This article provided Class II evidence that plasma NfL levels are elevated in pre-diagnostic ALS patients within 5 years of diagnosis and thus may be a useful biomarker in the earliest stage of ALS.
 
Articles of similar interest: Poesen K, Van Damme P. Diagnostic and prognostic performance of neurofilaments in ALS. Front Neurol. 2019;9:1167. doi: 10.3389/fneur.2018.01167
 
Poesen K, De Schaepdryver M, Stubendorff B, et al. Neurofilament markers for ALS correlate with extent of upper and lower motor neuron disease. Neurology. 2017 Jun;88(24):2302-2309. doi: 10.1212/WNL.0000000000004029