ABSTRACT
Background: Clinical trials of COVID-19 vaccination provide evidence of side effects in the placebo group, consistent with some side effects reporting being a nocebo effect (Amanzio M, et al. Lancet Reg Health Eur 2022;12:100253) Aim: To investigate whether side effects of COVID-19 vaccination are associated with negative beliefs about vaccination. Method(s): European patients with severe asthma (SHARP network) completed a questionnaire (May-June 2021) about their vaccination status, the Vaccination Attitudes EXamination (VAX) Scale, a measure of vaccination hesitancy related to four different types of belief, and if vaccinated whether they experienced side effects (none, mild, severe). Result(s): 660 patients from 12 European countries participated, of whom 497 had at least a first vaccination and also completed the VAX questions and side effects. Of these patients, those reporting severe side effects (5.7%) compared to those with mild (48.2%) or no side effects (43.8%) had significantly (p = 0.001, ANOVA) more mistrust of vaccine efficacy, more concerns about future effects and more concerns about profiteering but not significantly more preference for natural immunity (Fig 1). Conclusion(s): People with severe asthma who have negative beliefs about vaccination are more likely to report severe side effects to COVID-19 vaccination. Consistent with the nocebo effect, negative beliefs create negative expectations and side effects. (Figure Presented).