Risk Factors and Outcomes of COVID-19 in Thai Patients with Neuromyelitis Optica Spectrum Disorder: A Single Center Study

Background: Long-term immunotherapy use in patients with neuromyelitis optica spectrum disorder (NMOSD) raised concerns about the increased risk and severity of infection during the coronavirus disease 2019 (COVID-19) pandemic. Real-world data exploring the risks and outcomes of COVID-19 in NMOSD patients are warranted. Materials and Methods: A retrospective medical chart review of NMOSD patients at a tertiary care center in Thailand during the COVID-19 pandemic was performed. Patients with and without COVID-19 were compared using descriptive statistics. Among infected patients, those with asymptomatic-to-mild infection and severe-to-critical infection were compared. Univariate and multivariate logistic regression analyses for risk factors of infection were performed. Results: Of the 175 NMOSD, 24 (13.7%) patients had COVID-19. The risk factors for COVID-19 were type 2 diabetes mellitus (T2DM) (OR 14.72, 95% CI 3.17 to 68.43), rituximab use (OR 3.45, 95% CI 1.29 to 9.19), and younger age during the pandemic (OR 0.95, 95% CI 0.91 to 0.99). Four patients (16.7%) had a severe-to-critical disease, leading to one death. The more severe patients more commonly had comorbid T2DM, hypertension, and lymphopenia. Conclusion: NMOSD patients in Thailand had a higher infection rate than the general Thai population. In addition to the general risk factors of COVID-19, such as T2DM, NMOSD patients had an increased risk of infection from rituximab use.