Cerebrospinal fluid neurofilament light levels mark grey matter volume in clinically isolated syndrome suggestive of multiple sclerosis

BACKGROUND: Brain atrophy is a known marker of irreversible tissue damage in multiple sclerosis (MS). Cerebrospinal fluid (CSF) osteopontin (OPN) and neurofilament light chain (NF-L) have been proposed as candidate surrogate markers of inflammatory and neurodegenerative processes in MS. OBJECTIVE: To evaluate the relationship between CSF NF-L and OPN levels and brain grey and white matter volumes in patients with clinically isolated syndrome (CIS) suggestive of MS. METHODS: A total of 41 CIS patients and 30 neurological controls (NCs) were included. CSF NF-L and OPN were measured by commercial ELISA. Measures of brain volume (normalized brain volume (NBV), normalized grey matter volume (NGV), peripheral grey matter volume (PGV), normalized white matter volume (WMV), and ventricular volume) were obtained by SIENAX. Corpus callosum index (CCI) was calculated. Brain volumes were categorized into 'high' and 'low' according to the median value. RESULTS: CSF NF-L and OPN levels were higher in CIS patients in comparison with NCs. CIS patients with 'low' TGV, PGV, and TBV showed higher CSF NF-L levels than CIS patients with 'high' brain volumes. TGV and PGV correlated inversely with NF-L levels, whereas CCI was inversely related to OPN levels. CSF NF-L was the only independent predictor of TGV and PGV. CONCLUSION: CSF NF-L tracks mainly grey matter damage in patients with CIS suggestive of MS.