In MS, serum glial fibrillary acidic protein (sGFAP) represents a prognostic biomarker of disability progression independent of relapse activity (PIRA), according to findings published in JAMA Neurology. Jens Kuhle, MD, PhD, and colleagues examined patients with either stable or worsening disability and similar baseline Expanded Disability Status Scale scores with no relapses during follow-up (cohort 1; N=103) and patients on B-cell-depleting therapy (cohort 2; N=252). In cohort 1, patients with worsening progressive MS showed 50.9% higher sGFAP levels compared with those with stable MS after additional serum neurofilament light chain (sNfL) adjustment. Higher sGFAP at baseline was associated with accelerated gray matter brain volume loss (P<0.001) but not white matter loss. In cohort 2, median sGFAP z scores were higher in patients developing future confirmed disability worsening compared with those with stable disability (P=0.002); this was not significant for sNfL. Combined z score elevation of both biomarkers resulted in a four- to five-fold increased risk for confirmed disability worsening (HR, 4.09) and PIRA (HR, 4.71).
