Serum GFAP in multiple sclerosis: correlation with disease type and MRI markers of disease severity

Abstract

Neurofilament light chain (NfL) has been demonstrated to correlate with multiple sclerosis disease severity as well as treatment response. Nevertheless, additional serum biomarkers are still needed to better differentiate disease activity from disease progression. The aim of our study was to assess serum glial fibrillary acid protein (s-GFAP) and neurofilament light chain (s-NfL) in a cohort of 129 multiple sclerosis (MS) patients. Eighteen primary progressive multiple sclerosis (PPMS) and 111 relapsing remitting MS (RRMS) were included. We showed that these 2 biomarkers were significantly correlated with each other (R = 0.72, p < 0.001). Moreover, both biomarkers were higher in PPMS than in RRMS even if multivariate analysis only confirmed this difference for s-GFAP (130.3 ± 72.8 pg/ml vs 83.4 ± 41.1 pg/ml, p = 0.008). Finally, s-GFAP was correlated with white matter lesion load and inversely correlated with WM and GM volume. Our results seem to confirm the added value of s-GFAP in the context of multiple sclerosis.

Figure 1

(A) S-GFAP and s-NfL levels are correlated in MS patients (r = 0.66, p = 1e−06). Serum and CSF GFAP (B) and NfL (C) were correlated (r = 0.58, p = 1e−04 and r = 0.48, p = 0.0012). s-GFAP (D) and s-NfL (E) levels are higher in PPMS than in RRMS (respectively 130.3 ± 72.8 vs 83.4 ± 41.1 pg/ml and 13.63 pg/ml 6.60 vs. 9.33 pg/ml 4.52 pg/ml). S-GFAP is correlated with white matter lesions volume (F, r = 0.39, p = 0.0093) and is negatively correlated with white matter (G, r = − 0.4, p = 0.063), grey matter (H, r =  − 0.38, p = 0.0093) and cortical grey matter (I, r = − 0.37, p = 0.0115) volumes.