Cerebrospinal Fluid Oligoclonal Immunoglobulin Gamma Bands and Long-term Disability Progression in Multiple Sclerosis: a Retrospective Cohort Study

Abstract

\n Multiple sclerosis (MS) patients with and without the oligoclonal band (OCB) distribution of immunoglobulin gamma (IgG) in the cerebrospinal fluid (CSF) has a different genetic background and brain MRI features. In this study we have aimed to determine whether CSF-OCB status is associated with long-term disability outcomes. We used Swedish MS register data on clinically definite MS patients with known OCB status. Date of birth, MS onset and date at sustained Expanded Disability Status Scale (EDSS) score milestones 3, 4, 6, date at conversion to secondary progressive (SP) MS, sex, and immunomodulatory treatment (IMTs) duration were collected. Multivariate Cox regression models were used to investigate the association between OCB status and risk of reaching each milestone. The OCB-positive group reached disability milestones at earlier time and at younger age. OCB-positivity significantly increased the risk of reaching EDSS score 3.0 (HR=1.29, 95%CI: 1.12 to 1.48, P<0.001) and 4.0 (HR= 1.38, 95%CI: 1.17 to 1.63, P<0.001). The OCB-positive group had a 20 % higher risk to convert to SPMS. CSF-OCBs presence is associated with higher risk to reach EDSS milestones and to convert to SPMS. Our findings suggest higher disease modifying effect of OCB presence in the early inflammatory stages of MS.