Nocebo-Prone Behavior Contributes to SARS-CoV-2 Vaccine Hesitancy in Healthcare Workers

Background: (298 w)Vaccine hesitancy among healthcare workers (HCWs) represents a major challenge in the global fight against COVID19. A skeptical approach to vaccination could be linked to a higher susceptibility to nocebo effects, i.e. adverse events (AEs) experienced after medical treatments due to negative expectations. However, the association of nocebo-prone behavior with SARS-COV-2 vaccination hesitancy and tolerability has not been studied. Methods: A cross-sectional, multicenter, face-to-face survey was performed with a self-completed questionnaire that was delivered to a representative sample of HCWs of five tertiary hospitals in Athens four months after the SARS-COV2 vaccination rollout for HCWs. The questionnaire was designed to capture the reasons for vaccination hesitancy, vaccination-related AEs, and nocebo prone behavior, by a validated tool (Q-No) for the identification of nocebo-prone individuals.  Findings: A total of 1,309 HCWs (67·2%women; 43·4% physicians; 28·4% nurses; 11·5% administrative staff; 16·6% other personnel) completed the questionnaires (90·7% participation rate), among whom 237 (18·1%) had declined vaccination. Q-No scores were ≥15 in 325 participants (24·8%, mean age±SD=43·2±11·3), suggesting nocebo-prone behavior. Odds of vaccination were 57% lower in participants with Q-No score ≥15, than in those with a score <15 (OR=0.43, 95% CI:0.30-0.60), and 42% lower in females than men (OR=0.58, 95% CI:0.30-0.60), while physicians had higher odds of vaccination (OR=4.73, 95% CI:3·1-7·3) as compared to other HCWs. At least one AE was reported by 67·5% of vaccinees, mostly local pain and flu-like symptoms. Females and physicians had a higher probability to report AEs, which was not affected by the Q-No score.  Interpretation: Nocebo-prone behavior in HCWs as captured by the Q-No tool is associated with SARS-CoV-2 vaccination hesitancy. These findings point to a role of nocebo-related mechanisms in the development of vaccination hesitancy, and a potential benefit of a campaign focused on the nocebo effect with regard to improved vaccination rates. Funding: None to declare. Declaration of Interest: None to declare. Ethical Approval: This study was approved by the Ethic Committees of all five Hospitals.