Factors associated with persistence and clearance of high-risk oral HPV among participants in the HPV Infection in Men (HIM) study.

BACKGROUND HPV attributable oropharyngeal cancer (HPV-OPC) incidence is increasing in many high-income countries among men. Factors associated with oral HPV persistence, the precursor of HPV-OPC, is unknown. Data from the HPV Infection in Men (HIM) study which followed participants >7 years were utilized to examine rates of persistence and associated factors. METHODS Oral gargle samples from 3095 HIM study participants were HPV genotyped using SPF10 PCR-DEIA-LiPA25 assay. Oral HPV persistence for individual and grouped high-risk HPV types among 184 men positive for any high-risk HPV at their oral baseline visit was assessed at 6-month intervals. Factors associated with grouped high-risk HPV and HPV16 persistence were examined using logistic regression. Kaplan-Meier curves were constructed to examine median time to HPV clearance overall, and by selected risk factors. RESULTS Among the 7 HPV vaccine types, HPV33 had the longest median duration (7.6 months) followed by HPV16 and HPV45 (6.4 months). 10-30% of oral high-risk HPV infections persisted >24 months. Six months persistence of oral high-risk HPV infections was positively associated with age and gingivitis and negatively associated with lifetime number of sexual partners, while twelve months persistence was only inversely associated with lifetime number of sexual partners. Oral HPV16 persistence was positively associated with baseline HPV16 L1 antibody status. CONCLUSIONS 18% of HPV16 infections persisted beyond 24 months potentially conferring higher risk of HPV-OPC among these men. Older age appears to be an important and consistently reported factor associated with oral high-risk HPV persistence. More studies among healthy men are required to understand the progression of oral HPV infection to HPV-OPC.