Oral human papillomavirus infection in England and associated risk factors: a case-control study

OBJECTIVES: This study was conducted to determine the prevalence of and associated risk factors for infection with oral high-risk human papillomavirus (HR-HPV) in adult participants within England, and to explore any association with oral mucosal buccal epithelial cell and whole blood folate concentration. DESIGN: This was an observational study to determine oral HR-HPV prevalence in the study population. A case-control study was performed to explore the association between infection and folate status. SETTING: This study was conducted in Sheffield, UK, between April 2013 and August 2014. PARTICIPANTS: Seven hundred participants, aged 18-60 years, were recruited from university students (n=179), university and hospital staff (n=163), dental hospital patients (n=13), Sexual Health Sheffield patients (n=122) and the general public (n=223). INTERVENTIONS: Participants completed a lifestyle and sexual behaviour questionnaire, provided an oral rinse and gargle sample for the detection of oral HR-HPV and an oral mucosal buccal epithelial cell sample for the measurement of oral mucosal buccal epithelial cell folate. A blood sample was collected for measurement of whole blood folate concentration. OUTCOME MEASURES: The prevalence of oral HR-HPV infection in the study population was the primary outcome measure. Secondary outcome measures included associations between risk factors, folate status and infection. RESULTS: The prevalence of oral HR-HPV infection in this cohort was 2.2% (15/680) with 0.7% (5/680) positive for HPV16 or HPV18. Twenty samples were excluded due to insufficient material for HPV detection. Participants with oral HR-HPV infection were more likely to be a former smoker, and have a greater number of sexual and oral sexual partners. Folate status was not linked to likelihood of HPV infection. CONCLUSIONS: The prevalence of oral infection with HR-HPV in adult men and women in Sheffield in the North of England was low. Smoking and sexual behaviour were associated with HR-HPV positivity. TRIAL REGISTRATION NUMBER: ID14106