Cancer Epidemiol Biomarkers Prev. 2021 Oct 18:cebp.0625.2021. doi: 10.1158/1055-9965.EPI-21-0625. Online ahead of print.
ABSTRACT
BACKGROUND: Human papillomavirus (HPV) vaccine effectiveness (VE) evaluations provide important information for vaccination programs. We established a linkage between statewide central registries in Michigan to estimate HPV VE against in situ and invasive cervical lesions (CIN3+).
METHODS: We linked females in Michigan’s immunization and cancer registries using birth records to establish a cohort of 773,193 women with known vaccination history, of whom 3,838 were diagnosed with CIN3+. Residential address histories from a stratified random sample were used to establish a subcohort of 1,374 women without CIN3+ and 2,900 with CIN3+ among continuous Michigan residents. VE and 95% confidence intervals (CI) were estimated using cohort and case-cohort methods for up-to-date (UTD) vaccination and incomplete vaccination with 1 and 2 doses, and stratified by age at vaccination.
RESULTS: Both analytic approaches demonstrated lower CIN3+ risk with UTD and non-UTD vaccination vs. no vaccination. The cohort analysis yielded VE estimates of 66% (95% CI 60-71%) for UTD, 33% (95% CI 18-46%) for 2 doses-not UTD, and 40% (95% CI 27-50%) for 1 dose. The case-cohort analysis yielded VE estimates of 72% (95% CI 64-79%) for UTD, 39% (95% CI 10-58%) for 2 doses-not UTD, and 48% (95% CI 25-63%) for 1 dose. VE was higher for vaccination at age <20 than {greater than or equal to}20 years.
CONCLUSIONS: The statewide registry linkage found significant VE against CIN3+ with incomplete HPV vaccination, and an even higher VE with UTD vaccination.
IMPACT: Future VE evaluations by number of doses for women vaccinated at younger ages may further clarify dose-related effectiveness.
PMID:34663615 | DOI:10.1158/1055-9965.EPI-21-0625
