Impact of HPV Vaccination on the Incidence of High-Grade Cervical Intraepithelial Neoplasia (CIN2+) in Women Aged 20-25 in the Northern Part of Norway: A 15-Year Study

This study aimed to assess the impact of HPV vaccination on the incidence of high-grade cervical precursors (CIN2+) among women aged 20-25 in Troms and Finnmark over a 15-year period.MATERIALS AND METHODS: In this time series study, we analyzed cervical screening data from 15,328 women aged 20-25 in Troms and Finnmark, collected between 2008 and 2022. Statistical methods, including linear and logistic regression, were employed to evaluate changes in cervical intraepithelial neoplasia grade 2 and worse (CIN2+) incidence and compare risks between vaccine-offered cohorts and pre-vaccine cohorts.RESULTS: The incidence of CIN2+ initially increased from 31 cases per year in 2008 to 110 cases in 2018, then significantly decreased to 44 cases per year by 2022 (p < 0.01). Women in pre-vaccine cohorts had a substantially higher risk of CIN2+ (OR 9.02, 95% CI 5.9-13.8) and CIN3+ (OR 19.6, 95% CI 7.3-52.6). Notably, no vaccinated women with CIN2+ tested positive for HPV types 16 or 18. Furthermore, none of the 13 cervical cancer cases recorded during the study were from the vaccinated cohorts.INTERPRETATION: The findings suggest a significant reduction in the incidence of high-grade cervical precursors following the introduction of the HPV vaccine in Norway's national immunization program, highlighting its effectiveness in cervical cancer prevention among young women in Northern Norway.PMID:38675803 | DOI:10.3390/vaccines12040421
Source: Cancer Control - Category: Cancer & Oncology Authors: Source Type: research