Peripheral Inflammation as a Biomarker of Disease Activity in Relapsing-Remitting MS

Relapsing-remitting multiple sclerosis (RRMS) is a chronic autoimmune disorder of the central nervous system, marked by unexpected episodes of neurological impairment and inflammation. Peripheral inflammatory indicators are becoming recognized as noninvasive predictors of disease activity, progression, and subsequent assessment, complementing traditional clinical and radiographic evaluations. To examine the correlations between disease activity and peripheral inflammatory biomarkers-interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), high-sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and serum neurofilament light chain (sNfL)-in patients with relapsing-remitting multiple sclerosis (RRMS).

Prospective observational research encompassed 250 RRMS patients from January 2024 to May 2025, who attended Tikrit Teaching Hospital and private neurology clinics. Patients received baseline and 12-month MRI scans, together with a clinical evaluation utilizing the Expanded Disability Status Scale (EDSS). Inflammatory markers and sNfL were assessed in peripheral blood samples. Investigations were conducted on the correlations among biomarkers, clinical impairment, and MRI lesion burden.

The average age of the population studied was 34.6 ± 8.7 years, and 64% of patients were women. Elevation of IL-6 (4.8 ± 2.0 pg/mL), TNF-α (6.1 ± 2.3 pg/mL), and hs-CRP and ESR sNfL (18.5 ± 6.4 pg/mL) with a positive correlation to EDSS score and MRI lesional load (p < 0.05) was observed. MRI showed a reduction in inflammatory lesions, whereas the number of black T1 holes increased over 12 months (indicating ongoing neurodegeneration).

Soluble NfL, IL-6, and TNF-α are convenient markers of inflammation to reflect signal relay disease activity in RRMS. Their association with the clinical and radiographic findings may assist in personalizing the therapeutic approach.