Del Mistro A, Battagello J, Weis L, Bressan V, Selle V, Ramigni M, Dal Zotto A, Maggiolo A, Gori S, Frayle H, Zappa M, Zorzi M, The Consensus Study Veneto Working Group.
Viruses. 2021 Mar 16;13(3):486. doi: 10.3390/v13030486.
Abstract
Background: Efficacy for cervical cancer prevention of opportunistic HPV vaccination in post-pubertal girls is lower than in 11-year-olds.
Methods: Women born between 1986 and 1992 vaccinated at 15-25 years of age (at least one dose of 4-valent HPV vaccine) and screened at 24-27 years of age were included. Frequency of opportunistic vaccination, overall and by birth cohort, was calculated; screening outcomes were compared between vaccinated and unvaccinated women.
Results: Overall, 4718 (4.9%) HPV-vaccinated, and 91,512 unvaccinated, women were studied. The frequency of vaccination increased by birth cohort, ranging between 1.8% and 9.8%; age at vaccination decreased progressively by birth cohort (p < 0.0001). Participation in screening was 60.8% among vaccinated, and 56.6% among unvaccinated, women (p < 0.0001). Detection rates (DR) for high-grade lesions were lower in vaccinated women (2.11‰ vs. 3.85‰ in unvaccinated, for CIN3+, p = 0.24; 0.0‰ vs. 0.22‰ for cancer). The DR of CIN3+ increased with age at vaccination, scoring respectively 0.0‰, 0.83‰, and 4.68‰ for women vaccinated when they were 15-16, 17-20, and 21-25 years old (p = 0.17).
Conclusions: In comparison to unvaccinated women, higher compliance with cervical cancer screening invitation and lower CIN3+ DR among vaccinated women was observed. Age at vaccination was inversely correlated to vaccination efficacy.