CSF Neurofilament Light Chain Elevation Predicts ALS Severity and Progression

Area of Science:

• Neuroscience
• Biochemistry
• Neurology

Background:

• Neurofilament light chain (NFL) is a biomarker for neuroaxonal damage.
• Elevated NFL levels in cerebrospinal fluid (CSF) have been observed in various neurological disorders.

Purpose of the Study:

• To compare CSF NFL levels in patients with sporadic amyotrophic lateral sclerosis (sALS) against other neurological diseases and healthy controls.
• To assess the correlation between CSF NFL levels and clinical indicators of sALS, including disease severity and progression rate.

Main Methods:

• CSF samples were collected from patients with sALS, other central nervous system diseases (OCNSDs), immune-mediated peripheral neuropathy (IMPN), non-immune-mediated peripheral neuropathy (NIMPN), and healthy controls (HCs).
• Enzyme-linked immunosorbent assays (ELISAs) were utilized to quantify NFL concentrations in CSF.
• Clinical data, including ALS Functional Rating Scale-Revised (ALSFRS-R) scores and disease progression rates, were collected for sALS patients.

Main Results:

• Median CSF NFL levels were highest in sALS (6510 pg/mL), followed by OCNSD (5372 pg/mL), IMPN (4320 pg/mL), NIMPN (1477 pg/mL), and HCs (756 pg/mL).
• CSF NFL levels did not significantly differ between sALS, IMPN, and OCNSD groups but were significantly higher than in NIMPN and HC groups.
• A negative correlation was found between CSF NFL levels and ALSFRS-R scores, while a positive correlation existed with disease progression rate in sALS patients.

Conclusions:

• CSF NFL levels alone may not be sufficient to differentiate sALS from other central nervous system diseases or peripheral neuropathies.
• CSF NFL levels serve as a valuable predictor of disease severity and progression in patients with sALS.