Work

Risk of Juvenile Idiopathic Arthritis Following HPV9 Vaccination: A Retrospective Cohort Study Before and During the COVID-19 Pandemic

Year: 2025

Type: article

Abstract: Objective To evaluate whether 9-valent human papillomavirus (HPV9) vaccination is associated with an increased risk of juvenile idiopathic arthritis (JIA), particularly during the coronavirus disease-2019 (COVID-19) pandemic. Patients and Methods We conducted a retrospective cohort study using TriNetX U.S. Collaborative Network data from January 1, 2016, to December 31, 2023. Girls aged 9-13 years who received their first HPV9 dose in either the prepandemic (2016-2019) or pandemic (2020-2023) period were matched with unvaccinated controls. Exclusion criteria included previous JIA diagnosis, antirheumatic drug use, or positive rheumatoid factor. Incidence of new-onset JIA was tracked over 8 days to 36 months. Cox regression and Kaplan-Meier survival analysis were used to evaluate hazard ratios (HRs) and JIA-free survival. Results Among 99,243 vaccinated and 1.1 million control individuals, HPV9 recipients had a significantly reduced risk of JIA at 36 months in both periods (HR 2016-2019, 0.207, P <.001; HR 2020-2023, 0.287, P <.001). No increased risk was observed during the early postvaccination period. The estimated cumulative probability of JIA did not differ significantly between vaccinated groups across the 2 periods ( P =.9), nor among unvaccinated controls ( P =.238), indicating no modifying effect from COVID-19. Conclusion The HPV9 vaccination was associated with a lower risk of JIA, and this effect can last at least for 3 years. The COVID-19 pandemic did not alter this relationship. These findings reinforce the immunological safety of HPV9 and provide reassurance for adolescent vaccination programs, even in pandemic contexts.

Source: Mayo Clinic Proceedings Innovations Quality & Outcomes

DOI: 10.1016/j.mayocpiqo.2025.100647

Authors: Ming-Chin Tsai, Hsin-Hua Chen, Wen-Yu Wu, Yung-Chieh Huang, Chiann-Yi Hsu, Lin-Shien Fu

Institutions: Taichung Veterans General Hospital, National Chung Hsing University

Language: English

Topic: Cervical Cancer and HPV Research

Subfield: Epidemiology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,000