The effects of the national HPV vaccination programme in England, UK, on cervical cancer and grade 3 cervical intraepithelial neoplasia incidence: a register-based observational study
- Study type
- Observational study
- Design
- Population register-based observational study using an age-period-cohort Poisson model, comparing vaccinated cohorts with earlier cohorts that had not been eligible for the vaccine
- Sample size
- 13.7 million person-years of follow-up in women aged 20 to under 30 years
- Source
- The Lancet · 2021
In plain words
In England, the HPV vaccine has been offered to teenage girls since 2008. This study showed that after this programme, cervical cancer and advanced precancerous changes of the cervix (CIN3) became much less common in young women. The biggest drop was seen in girls who had received the vaccine at age 12 to 13. These findings show the importance of vaccinating at a young age.
Key results
Treatment arms and regimens
The bivalent HPV vaccine (Cervarix), introduced in England on 1 September 2008: routine vaccination for girls aged 12 to 13 years and a catch-up programme for those aged 14 to 18 years in 2008 to 2010. The three vaccinated cohorts were defined by age when the vaccine was offered: 16 to 18 years (school years 12 to 13), 14 to 16 years (school years 10 to 11) and 12 to 13 years (school year 8). The number of vaccine doses is not given in the abstract (observational study of a national programme).
Earlier cohorts that were not eligible for the HPV vaccine.
Source of the regimen details: Abstract of the paper (observational study of a national vaccination programme; no drug regimen with doses)
Doses are given for the information of specialists, as in this study’s protocol, and are not a prescription. Every drug must be prescribed by the treating physician for the individual patient.
Study population
Women aged 20 to 64 years resident in England who were assessed in the population cancer registry for diagnoses of cervical cancer and CIN3 between 1 January 2006 and 30 June 2019. The main results were reported from 13.7 million person-years of follow-up in women aged 20 to under 30 years.
Endpoints
Estimated relative risk of cervical cancer and carcinoma in situ (grade 3 cervical intraepithelial neoplasia, CIN3) in three vaccinated cohorts compared with unvaccinated cohorts. Adjustment for confounders used information on changes in cervical screening policy and historical events affecting cervical cancer incidence.
Safety and side effects
This study focused on the effectiveness of the vaccination programme on the incidence of cervical cancer and CIN3, and no safety data are reported in the abstract.
Clinical significance and place in guidelines
This study provides real-world, population-level evidence of the effect of the national HPV vaccination programme in reducing cervical cancer and CIN3, and shows that vaccination at age 12 to 13 years brought the greatest risk reduction. The abstract gives no information on direct changes to guidelines or drug approvals; the status of guideline recommendations should be checked separately.
Limitations
This study is observational and not randomised; the comparison is based on vaccinated and unvaccinated cohorts and statistical modelling, and adjustment for confounders (such as changes in screening policy) was made with the information available. The abstract does not address other limitations; details are in the full text of the paper.
This summary was prepared by the editorial team from the published paper; the original paper is the final reference. Read the original abstract on PubMed.