Association of gray and white matter volumes, clinical features, neurofilament light chain, and glial fibrillary acidic protein in relapsing-remitting multiple sclerosis.

Background: Numerous studies have examined the prognosis of patients with relapsing-remitting multiple sclerosis (RRMS).

Purpose: To seek a relationship between the gray matter/white matter (GM/WM) volume ratio, clinical features, neurofilament light chain (NfL), and glial fibrillary acidic protein (GFAP) in RRMS.

Material and methods: A total of 61 patients aged 18-70 years with RRMS and 20 controls were included. Neurological examinations were noted at the first attack and last visit. Blood samples were taken in remission.

Results: Patients' WM volume was lower and the GM/WM volume ratio was larger than in the controls (P < 0.001). Patients' WM correlated with GM volume (P < 0.001, r = 0.608). WM correlated with GM/WM volume ratio (P < 0.001, r = -0.632). For NfL and GFAP, no difference was found between patients and controls. Patients' NfL correlated with GFAP (P < 0.001, r = 0.452). Age and disease duration were correlated with Gfap (P < 0.001, r = 0.434; P < 0.002, r = 0.381). No correlation was found between NfL/GFAP levels and all volumetric measurements of patients. Higher Expanded Disability Status Scale (EDSS), lower GM and WM volumes, and greater GM/WM volume ratio were detected in patients with the first pyramidal findings (P < 0.001).

Conclusion: Patients' NfL and GFAP levels were lower than in controls and did not correlate with all volumes. GFAP is more informative, particularly in patients of advanced age and those with longstanding diseases. Higher EDSS and decreased GM and WM volumes were seen in patients with pyramidal symptoms at the first attack.