Cognitive Impairment and Quality of Life in AQP4-IgG Seropositive Neuromyelitis Optica Spectrum Disorder: A Cross-Sectional Study in Iranian Patients

Abstract

Background: Cognitive impairment (CI) has been reported with wide variability in neuromyelitis optica spectrum disorder (NMOSD), but its impact on patients' quality of life (QoL) is not well understood. The aim of this study was to describe the cognitive characteristics and various aspects of QoL of NMOSD patients. Methods: This cross-sectional study included 49 NMOSD patients (30 seropositive for AQP4-IgG) and 43 healthy controls (HCs). A set of questionnaires, including information of demographic and clinical characteristics, Multiple Sclerosis Quality of Life-54 (MSQOL-54), Beck Depression Inventory (BDI), and Hospital Anxiety and Depression Scale (HADS), was completed. Cognitive assessment was performed using the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) by a trained individual. Results: Based on CI criteria, 24 patients (48.98) were classified as cognitively impaired, of whom 20 (83.33) were AQP4-IgG seropositive. There was a strong positive correlation between CI and AQP4-IgG seropositivity (p < 0.05). Seropositive patients performed worse on the PASAT (p < 0.05) and D-KEFS (p < 0.001) tests of MACFIMS. None of the MSQOL-54 subscale scores were significantly affected by AQP4-IgG seropositivity, and there was no significant relationship between the physical or mental health composite score of the MSQOL-54 and CI. Conclusion: Our findings suggest that cognitive impairment is a relevant yet underrecognized feature of NMOSD, particularly among AQP4-IgG seropositive patients. The lack of association between CI and QoL highlights the need for more sensitive, disease-specific assessment tools. Further longitudinal and multicenter research is warranted to clarify the mechanisms and clinical impact of these impairments.