Factors associated with fatigue in CNS inflammatory diseases with AQP4 and MOG antibodies

Abstract

Objective: Fatigue is a common and disabling symptom amongst people withmultiple sclerosis, however it has not been compared across the central nervoussystem (CNS) inflammatory diseases associated with aquaporin-4 (AQP4) andmyelin oligodendrocyte glycoprotein (MOG) antibodies (Ab). We explored thefactors associated with fatigue within and across the two diseases, and comparedfatigue levels between them.Methods: We performed a cross-sectional study of90 AQP4-Ab and 44 MOG-Ab patients. Fatigue was assessed using the ModifiedFatigue Impact Scale (MFIS). Clinical, demographic, and psychometric (anxiety,depression, pain) data were used as independent variables. Multivariable linearregression was used to identify significant independent variables associated withfatigue within and across the two diseases.Results: Within AQP4-Ab patients,age (P= 0.002), disease duration (P= 0.004), number of clinical attacks(P= 0.001), disability (P= 0.007), pain interference (P< 0.001), anxiety(P= 0.026), and depression (P< 0.001) were significant independent variables.Interestingly, disease duration had a negative association with fatigue(P= 0.004). Within MOG-Ab patients, pain interference score (P< 0.001) andanxiety (P= 0.001) were significant independent variables. Although fatigue wasworse in AQP4-Ab patients compared to MOG-Ab patients (P= 0.008) in allpatients as well as in those who ever had transverse myelitis (P= 0.023), this wasdriven by the differences in age, disability and pain interference rather than anti-body subtype itself.Interpretation: Multiple factors, but not the antibody speci-ficity, appear to contribute to fatigue in antibody positive CNS inflammatorydiseases. A multifaceted treatment approach is needed to better manage the phys-ical, cognitive, and psychosocial aspects of fatigue in these patients