Effectiveness of the Human Papillomavirus Vaccine in Extended Age Groups: A Real-World Analysis Based on the Korean HPV Cohort Study.

BACKGROUND/OBJECTIVES: This study evaluated the real-world effectiveness of prophylactic Human Papillomavirus (HPV) vaccination in Korean women aged over 26 years, focusing on its impact on persistent HPV infection and disease progression.

METHODS

This multicenter prospective study analyzed data from the Korea HPV Cohort (2010-2021). After applying exclusion criteria, the final analytical cohort included 1,231 women aged ≥ 27 years with cytologic findings of atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesions and HPV infection. Propensity score matching was used to compare vaccinated ( = 340) and unvaccinated ( = 891) participants. After matching, 273 vaccinated and 273 unvaccinated individuals were included in the final analysis. The primary outcomes were persistent HPV infection and progression to biopsy-confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Logistic and Cox regression models were employed, with additional age-stratified analyses.

RESULTS

Among women aged 27-39 years, vaccination was significantly associated with a 54% reduction in the odds of persistent HPV infection (odds ratio = 0.46; 95% CI: 0.22-0.96; = 0.040). In the full cohort, vaccinated participants had a 62% lower risk of progression to CIN2+ compared with unvaccinated participants (hazard ratio = 0.38; 95% CI: 0.18-0.81; = 0.011). Body mass index had a notable impact on HPV persistence in HPV 16/18 genotype groups.

CONCLUSIONS

HPV vaccination effectively reduced persistent infection and progression to CIN2+ in Korean women, particularly those vaccinated before age 40. These findings support the age-extended HPV vaccination policies in South Korea.