The changing nature of HPV associated with high grade cervical lesions in vaccinated populations, a retrospective study of over 1700 cases in Scotland.

BACKGROUND

Understanding the pattern and dominance of HPV types in high grade cervical disease within increasingly vaccinated populations will help inform the development of appropriate screening and management protocols.

METHODS

Over 1700 cases of cervical intraepithelial neoplasia (CIN) diagnosed between 2011 and 2017 in women younger than 25 were genotyped for HPV. Logistic regression was used to assess the association between HPV 16/18 positivity with biopsy-collection year, birth year, deprivation and vaccination status. Regression analysis was repeated for cross-protective types (31, 33 and 45). Type specific detail of non-vaccine types by vaccination status was presented descriptively.

RESULTS

Detection of HPV 16/18 or 16/18/31/33 and 45 was lower in CIN2 associated with full vaccination vs no vaccination (OR 0.3; 95% CI 0.2-0.5 & 0.4; 95% CI 0.3-0.6 respectively) Similar observations were made for CIN3. The relative contribution of non-established high-risk types including those considered low risk was greater among vaccinated women with CIN2+ vs unvaccinated women with CIN2+.

CONCLUSIONS

The change in HPV distribution in CIN2+ in vaccinated populations is a further marker of vaccine impact. Additionally, the progression rate of CIN2+ in vaccinated populations may be lower given the shift in type distribution. The definition of high grade disease in vaccinated populations may warrant reassessment.