{
  "abstract": "Background and objectives Disability in aquaporin-4 antibody-positive neuromyelitis optica spectrum disease (AQP4-IgG NMOSD) is considered relapse-driven although subclinical injury has been suggested by neuroimaging and visual pathway assessments. We investigated longitudinal changes in serum glial fibrillar acidic protein (sGFAP) and neurofilament light chain (sNfL) during relapse-free periods.Methods We conducted a retrospective longitudinal study (2008–2025) at a UK national referral centre for NMOSD. Patients with ≥3 serum samples collected over ≥3 years were included; samples within 3 months of relapses were excluded. Longitudinal changes in sGFAP and sNfL were assessed using linear mixed-effects models with random intercepts and generalised estimating equations, adjusting for age, sex and time.Results 40 patients (87.5% females; 162 samples; median onset age 40.1 years) and 28 matched controls were included. Over the course of four measurements and a median sampling over 9 years, stability was observed in sGFAP levels (99.2 pg/mL at 0–2.5 years (95% CI 84.2 to 117.0) to 90.3 pg/mL at 7.5–10 years (95% CI 74.7 to 109.0), p=0.65) and sNfL levels (12.0 pg/mL at 0–2.5 years (95% CI 10.8 to 13.3) to 10.4 pg/mL (9.1 to 11.8) at 7.5–10 years, p=0.12) after adjustment for covariates.Discussion In this longitudinal study, mean sGFAP and sNfL levels remained stable over 9 years of sequential measurements during relapse-free periods, supporting the relapse-driven nature of NMOSD pathology.",
  "authors": [
    {
      "affiliations": [
        "Department of Neuroscience, School of Translational Medicine, Monash University, Melbourne, Victoria, Australia",
        "Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia",
        "Neurology, The Walton Centre, Liverpool, UK"
      ],
      "name": "Pakeeran Siriratnam"
    },
    {
      "affiliations": [
        "NIHR Health Protection Research Unit for Emerging and Zoonotic Infection, Liverpool, UK",
        "Liverpool Interdisciplinary Neuroscience Centre (LINC), University of Liverpool, Liverpool, UK",
        "Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Science, University of Liverpool, Liverpool, UK"
      ],
      "name": "Cordelia Dunai"
    },
    {
      "affiliations": [
        "NIHR Health Protection Research Unit for Emerging and Zoonotic Infection, Liverpool, UK",
        "Liverpool Interdisciplinary Neuroscience Centre (LINC), University of Liverpool, Liverpool, UK"
      ],
      "name": "Nkongho Egbe Franklyn"
    },
    {
      "affiliations": [
        "Neurology, The Walton Centre, Liverpool, UK"
      ],
      "name": "Samantha Linaker"
    },
    {
      "affiliations": [
        "Department of Neuroscience, School of Translational Medicine, Monash University, Melbourne, Victoria, Australia",
        "Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia"
      ],
      "name": "Robb Wesselingh"
    },
    {
      "affiliations": [
        "Neurology, The Walton Centre, Liverpool, UK",
        "Department of Neurology, Cleveland Clinic Abu Dhabi, Abu Dhabi, UAE"
      ],
      "name": "Anu Jacob"
    },
    {
      "affiliations": [
        "Neurology, The Walton Centre, Liverpool, UK"
      ],
      "name": "Edward Joseph Jackson"
    },
    {
      "affiliations": [
        "Department of Neuroscience, School of Translational Medicine, Monash University, Melbourne, Victoria, Australia",
        "Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia"
      ],
      "name": "Anneke van der Walt"
    },
    {
      "affiliations": [
        "Department of Neuroscience, School of Translational Medicine, Monash University, Melbourne, Victoria, Australia",
        "Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia"
      ],
      "name": "Vilija Jokubaitis"
    },
    {
      "affiliations": [
        "Department of Neuroscience, School of Translational Medicine, Monash University, Melbourne, Victoria, Australia",
        "Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia"
      ],
      "name": "Helmut Butzkueven"
    },
    {
      "affiliations": [
        "Department of Neuroscience, School of Translational Medicine, Monash University, Melbourne, Victoria, Australia",
        "Department of Neurology, Alfred Hospital, Melbourne, Victoria, Australia"
      ],
      "name": "Mastura Monif"
    },
    {
      "affiliations": [
        "Neurology, The Walton Centre, Liverpool, UK",
        "NIHR Health Protection Research Unit for Emerging and Zoonotic Infection, Liverpool, UK",
        "Liverpool Interdisciplinary Neuroscience Centre (LINC), University of Liverpool, Liverpool, UK",
        "Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Science, University of Liverpool, Liverpool, UK"
      ],
      "name": "Benedict D Michael"
    },
    {
      "affiliations": [
        "Liverpool Interdisciplinary Neuroscience Centre (LINC), University of Liverpool, Liverpool, UK",
        "Neurology, The Walton Centre NHS Foundation Trust, Liverpool, UK",
        "Department of Pharmacology and Therapeutics, University of Liverpool, Liverpool, UK"
      ],
      "name": "Saif Huda"
    }
  ],
  "title": "Inter-attack serum GFAP and NfL remain stable over 9 years in AQP4 IgG NMOSD",
  "uid": "360ec1d0-7547-573f-bd12-f9cbd025e216"
}