Factors associated with cognitive impairment in patients with neuromyelitis optica spectrum disorders from Mexico

Background: Patients with neuromyelitis optica spectrum disorders (NMOSD) often experience significant functional limitation, high rates of disability, and cognitive impairment (CI). The objective of this study was evaluating the factors associated with CI in patients diagnosed with NMOSD in Mexico. Methods: The study was cross-sectional in design. We included 65 NMOSD patients (34 NMOSD with CI and 31 NMOSD without CI). We utilized the Brief International Cognitive Assessment for Multiple Sclerosis to identify CI in NMOSD patients. Logistic regression was applied to identify the factors associated with CI. Results: Factors associated with CI in the crude analysis were education level (⩽6 years of schooling; odds ratio (OR) 4.37, 95% confidence interval (CI) 1.41-13.52, p = 0.010), disease duration (⩾60 months; OR 8.22, 95% CI 2.68-25.20, p < 0.001), time from onset to diagnosis (⩾12 months; OR 3.70, 95% CI 1.21-11.31, p = 0.022), brain lesion (on magnetic resonance imaging before azathioprine or rituximab; OR 3.46, 95% CI 1.20-10.00, p = 0.022), and relapses by NMOSD diagnosis (⩾4; OR 4.48, 95% CI 1.57-12.76, p = 0.005). Factors associated with CI in the adjusted analyses were education (⩽6 years; OR 5.92, 95% CI 1.57-22.23, p = 0.008), disease duration (⩾60 months; OR 5.73, 95% CI 1.69-19.40, p = 0.005), and relapses by NMOSD diagnosis (⩾4; OR 5.79, 95% CI 1.70-19.72, p = 0.005). Conclusion: One of the biggest factors associated with CI was relapse by NMOSD, specifically those with lower education levels and those with longer disease duration.