Short-term safety of inactivated SARS-Cov-2 vaccines in Chinese patients with central nervous system inflammatory demyelinating diseases

OBJECTIVE: This study aims to evaluate the short-term safety of inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in Chinese patients with central nervous system inflammatory demyelinating diseases (CNS IDDs). METHODS: A web-based survey was conducted among patients with CNS IDDs from April 15 to 19, 2022 in China. In total, 645 patients with CNS IDDs were identified, including 425 patients with multiple sclerosis (MS), 194 with neuromyelitis optica spectrum disorder (NMOSD), and 26 with other CNS IDDs. The questionnaire consisted of demographic data, clinical records, history of SARS-CoV-2 vaccination, and vaccination-related symptoms within one month after vaccination. The demographic data, clinical information, and relapse rates between vaccinated and non-vaccinated patients were compared. RESULTS: Among 645 patients with CNS IDDs, 78 were vaccinated and 567 were non-vaccinated with the vaccination rate of 12.1 %. Compared to non-vaccinated group, a lower percentage of patients on DMDs therapy (41.0 % vs. 71.8 %, P < 0.001) and an increased proportion of patients with other vaccination in past 3 years (17.9 % vs. 4.8 %, P < 0.001) were observed in vaccinated group. Six patients experienced a relapse within 30 days of a vaccination. Additionally, vaccine-associated relapse rates in vaccinated patients did not significantly differ from these in non-vaccinated patients among 2020, 2021, and from January 1 to October 1, 2022. CONCLUSIONS: No increased risk of vaccination-associated relapses among Chinese patients with CNS IDDs indicated that inactivated SARS-CoV-2 vaccines appear to be safe for this population.