Serum neurofilament light chain in myasthenia gravis subgroups: An exploratory cohort and case-Control study.

Background

This study aimed to evaluate the association of neurofilament light chain (Nfl) with neuromuscular destruction and disease severity in the serum of patients with myasthenia gravis (MG).

Materials and methods

Sera from 134 patients with MG with varying degrees of disease severity and autoantibody (Abs) status were analyzed and compared to controls in a cross-sectional design. Prospectively, we additionally measured serum NfL (sNfl) levels in patients with MG longitudinally for up to 3 years. Based on linear regression, differences between patients and controls were assessed. With correlation coefficients and mixed linear regression, the association among sNfl levels, socio-demographics, disease activity (Quantitative Myasthenia Gravis (QMG) score and Myasthenia Gravis Activities of Daily Living (MG-ADL) scale), Abs-status (acetylcholine receptor antibody (AChR-Abs), muscle-specific receptor tyrosine kinase antibody (MuSK-Abs), lipoprotein-related protein 4 (LRP4), and seronegative), Abs titer, treatment regime (pyridostigmine, steroids, and immunosuppressive therapies), and thymectomy were investigated.

Results

sNfl levels were higher in patients with MG compared to controls (median: 11.2 vs. 7.88), where sNfl levels were highest in anti-AChR-Abs positive patients (median 12.6), followed by anti-MuSK-Abs positive, anti-LRP4-Abs positive, and seronegative patients. Adjusting for age and sex, sNfl levels of patients with MG were on average 35% higher compared to controls (35.1, 95% CI: 8.4;68.3) and highest for patients with seronegative MG (44.35; 95% CI 16.47; 78.90). We found no relevant relationship between individual changes in sNfl and changes in QMG and MG-ADL scores.

Conclusion

sNfl levels are higher in patients with MG than in controls but were not consistently associated with clinical severity. Thus, sNfl is not a suitable biomarker to monitor individual disease progression in patients with MG.

Informations de copyright

Copyright © 2023 Stascheit, Aigner, Mergenthaler, Hotter, Hoffmann, Lehnerer, Meisel and Meisel.

Déclaration de conflit d'intérêts

CM was employed by Charité Vivantes GmbH. FS received speaking honoria and honoria for attendance at advisory boards from Alexion Pharmaceuticals. PM receives funding from the Einstein Foundation Berlin, and is supported by grants from the Bundesministerium für Bildung und Forschung, the Volkswagen Foundation, and the Else Kröner Fresenius Stiftung, and is on the board of HealthNextGen Inc. and has equity interest in the company. BH received financial research support by argnx. SH received speaker honoraria and honoria for attendance at advisory boards from Alexion Pharmaceuticals and argnx. SL reports speaker honoraria and honoraria for attendance at advisory boards from Alexion Pharmaceuticals. AM received speaker honoraria from Alexion, GRIFOLS and Hormosan. He received honoraria from Alexion, MorphoSys and Vitaccess for consulting services and financial research support from Octapharma and Alexion and is chairman of the medical advisory board of the German Myasthenia Gravis Society. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.