Human papillomavirus vaccination and the risk of autoimmune disorders: A systematic review and meta-analysis.

ABSTRACT

INTRODUCTION: Human papillomavirus (HPV) vaccination has been proven to effectively protect against HPV infection and infection-associated cancer. However, there are concerns about the relationship between HPV vaccination and the risk of autoimmune disorders (ADs). Therefore, we performed a systematic review and meta-analysis to comprehensively evaluate the relationship between HPV vaccination and ADs risk. METHODS: To identify relevant studies, we conducted a systematic search in EMBASE and PubMed databases of scientific articles published through June 2018. Fixed or random effects models were adopted to estimate overall relative risk. RESULTS: In total, 20 studies (12 cohort studies, 6 case-control studies, and 2 randomized controlled trials) involving more than 169,000 AD events were included in our meta-analysis. Our results show that HPV vaccination was not associated with an increased risk of subsequent ADs (odds ratio [OR] = 1.003, 95% confidence interval (CI) 0.95-1.06), particularly among those with a prior ADs (OR = 0.82, 95% CI 0.7-0.96). Most of the subgroup analysis results based on the location or type of ADs were consistent with the overall results. CONCLUSION: No evidence of an association between HPV vaccination and ADs was found. Given the low number of estimates for individual AD, additional and larger observational studies are needed to verify our findings.