Exploring the Association Between COVID-19 Vaccination and Mental Disorder Risks: A Retrospective Cohort Study

Introduction COVID-19 vaccines significantly reduce mortality and severe complications, but potential side effects warrant careful investigation. This study analyzed a large real-world dataset to examine the risk of psychiatric disorders following COVID-19 vaccination. Methods This retrospective cohort study was conducted using data from the TriNetX Research Network United States Collaboration. Patients were divided into vaccinated and nonvaccinated cohorts and matched at a 1:1 ratio using propensity scores based on age, sex, demographics, and underlying health conditions. The primary outcome was the incidence of newly diagnosed mental, behavioral, and neurodevelopmental disorders within 6 months after COVID-19 vaccination. Results The vaccinated cohort demonstrated a higher risk of mental, behavioral, and neurodevelopmental disorders (hazard ratio [HR]: 1.11, 95% confidence interval [CI]: 1.08–1.14). Specifically, increased risks were observed for mood disorders (HR: 1.31, 95% CI: 1.25–1.38), anxiety disorders (HR: 1.23, 95% CI: 1.18–1.28), and major depressive disorder (HR: 1.35, 95% CI: 1.28–1.42). Conversely, this group showed a lower risk of schizophrenia and related disorders (HR: 0.72, 95% CI: 0.59–0.88). Subgroup analyses revealed that these effects were more pronounced in younger individuals and female patients. Conclusion While COVID-19 vaccination remains essential for pandemic control and should be encouraged among all eligible individuals, our findings highlight the need for targeted mental health monitoring, particularly in younger individuals and women who may be more susceptible to psychological distress following vaccination.