Effects of COVID-19 and Influenza Vaccination on Rheumatic Diseases: Results From a Survey of Patient-Reported Outcomes After Vaccination

BACKGROUND: This study aimed to compare the occurrence of adverse events (AEs) and disease flares after vaccination against coronavirus disease 2019 (COVID-19) and influenza in patients with autoimmune rheumatic diseases (ARDs). METHODS: Between November 2021 and March 2022, a survey was conducted among patients with ARD who received COVID-19 and influenza vaccinations. The questionnaire included 11 mandatory and closed-ended questions, and the following items were collected: medical history, immunization history, type of vaccine, patient-reported AEs, flare-up of the underlying disease after vaccination, and a confirmed diagnosis of COVID-19 or influenza. We compared the occurrence of vaccine-related adverse reactions to the COVID-19 and influenza vaccines based on the survey results. Multivariate logistic regression analysis was used to identify the factors affecting AEs or disease flares and to compare the post-vaccine response to mixed and matched vaccines. RESULTS: We analyzed 601 adults with ARD who received the COVID-19 vaccine, with a mean age of 49.6 years (80.5% female). A total of 255 participants (42.4%) received a complete course of primary vaccination, 342 (56.9%) completed the booster dose, and 132 (38.6%) received a mixed vaccine. The frequencies of AEs (188 [52.2%] vs. 21 [5.8%]; P < 0.001) and disease flares (58 [16.2%] vs. 5 [1.4%]; P < 0.001) after COVID-19 vaccination were significantly higher than those after influenza vaccination. In the risk factor analysis, previous allergic reaction to other vaccines (odds ratio, 1.95; confidence interval, 1.07–3.70; P = 0.034) was the only factor associated with the occurrence of AEs. There was no difference in the post-vaccine responses between the mixed and matched vaccines. CONCLUSION: The results of the survey of patients with ARD revealed that patient-reported AEs and underlying disease flares after receiving the COVID-19 vaccine were significantly higher than those after the influenza vaccine.