Smoking increases oral HPV persistence among men: 7-year follow-up study.

Persistent high-risk human papillomavirus (HR-HPV) infection is the key event in the progression of HPV lesions, and more data are urgently needed on asymptomatic oral HPV infections in men. Asymptomatic fathers-to-be (n = 131, mean age 28.9 years) were enrolled in the cohort, sampled by serial oral scrapings at baseline and at 2-month, 6-month, 12-month, 24-month, 36-month, and 7-year follow-up visits to accomplish persistent and cleared HPV infections. HPV genotyping was performed using nested PCR and Multimetrix® assay. Covariates of persistent and cleared oral HPV infections were analysed using generalised estimating equation (GEE) and Poisson regression. Altogether, 17 HPV genotypes were detected in male oral mucosa point prevalence, varying from 15.1 % to 31.1 %. Genotype-specific HPV persistence was detected in 18/129 men the mean persistence time ranging from 6.0 to 30.7 months. History of genital warts decreased (p = 0.0001; OR = 0.41, 95 % CI 0.33-0.51) and smoking increased (p = 0.033, OR = 1.92, 95 % CI 1.05-3.50) the risk of persistent species 7/9 HPV infections. Of the 74 HPV-positive men, 71.6 % cleared their infection actuarial and crude clearance times, varying between 1.4 and 79.6 months. No independent predictors were identified for species 7/9 clearance. At the last follow-up-visit, 50.1 % of the fathers had oral mucosal changes, correlating only with smoking (p = 0.046). To conclude, most of the persisting oral infections in males were caused by HPV16. Smoking increased while previous genital warts decreased oral HR-HPV persistence. No predictors of HR-HPV clearance were disclosed.