Real-world effectiveness of Human Papillomavirus vaccination against vulvovaginal high-grade precancerous lesions and cancers

Menée à partir de données de registres portant sur 514 537 jeunes femmes vivant au Danemark entre 2006 et 2019 (âge : 17-26 ans ; durée médiane de suivi : 6,9 ans), cette étude évalue l'effet du vaccin anti-papillomavirus humain sur l'incidence des lésions vulvo-vaginales de haut grade

Résumé en anglais

Vaccination against human papillomavirus (HPV) has proven to be effective against severe cervical lesions and genital warts, whereas no previous study has provided real-world data on the HPV vaccine effectiveness against high-grade vulvovaginal lesions.A cohort of all women aged 17–26 years, living in Denmark during 2006–2019 was followed in nationwide registers for individual-level information about HPV vaccination and first diagnoses of vulvar and vaginal high-grade intraepithelial lesions or worse (HSIL+). The cumulative incidence of vulvar and vaginal HSIL+, respectively, was estimated with the Aalen-Johansen estimator and Cox proportional hazards regression was used to estimate hazard ratios (HRs) for vulvar and vaginal lesions separately comparing women vaccinated at age <16 years and at age 17–26 years with unvaccinated women.The cohort consisted of 514,537 women, of which 50.6% were vaccinated at baseline (<16 years), 31.8% were vaccinated during follow-up (17–26 years) and 17.6% remained unvaccinated. The cumulative incidence was less than 0.6‰ for vulvar HSIL+ and less than 0.2‰ for vaginal HSIL+. Adjusted analyses showed reduced hazard rates for both vulvar (HR = 0.22, 95% CI = 0.13 to 0.38) and vaginal HSIL + (HR = 0.16, 95% CI = 0.04 to 0.55) for women vaccinated at age ≤16 years compared to unvaccinated women. For women vaccinated at 17–26 years, the reductions in hazard rates were smaller for vaginal HSIL+ and close to zero for vulvar HSIL+.HPV vaccination before 17 years of age reduces the risk of vulvar and vaginal HSIL+ based on real-world data.