title: Factors associated with acquisition and clearance of human papillomavirus infection in a cohort of US men: a prospective study.
abstract: BACKGROUND
  Our understanding of factors associated with acquisition and clearance of human papillomavirus (HPV) in men has been limited. This study sought to determine factors associated with those aspects of HPV infection in a cohort of US men.
  
  
  METHODS
  A total of 285 men aged 18-44 years were monitored every 6 months for approximately 18 months. Risk-factor information was obtained at each visit by use of a self-administered questionnaire. A continuous-time 2-state Markov model was applied.
  
  
  RESULTS
  Lifetime number of sex partners reported at enrollment was the most significant risk factor for acquisition of all types of HPV. Men reporting >16 lifetime sex partners were at significantly elevated risk of any HPV infection (adjusted hazard ratio [AHR], 2.8 [95% confidence interval {CI}, 1.1-7.1]), oncogenic HPV infection (AHR, 9.6 [95% CI, 2.4-37.8]), and nononcogenic HPV infection (AHR, 3.6 [95% CI, 1.3-9.9]), compared with those reporting 0-4 partners. Circumcised men were 3 and 6 times more likely to clear infection with any and oncogenic HPV types, respectively. In addition, having had >16 lifetime sex partners was associated with greater likelihood of clearance of oncogenic HPV infection (AHR, 4.9 [95% CI, 1.2-19.8]).
  
  
  CONCLUSIONS
  The key factor associated with acquisition of HPV was lifetime number of sex partners, whereas circumcision was the most significant determinant for clearance of any HPV infection and oncogenic HPV infection.
authors.affiliation: H. Lee Moffitt Cancer Center and Research Institute, Department of Epidemiology and Biostatistics, College of Public Health, University of South Florida, Tampa, FL 33612-9416, USA.
authors.forename: Beibei
authors.initials: B
authors.lastname: Lu
authors.forename: Yougui
authors.initials: Y
authors.lastname: Wu
authors.forename: Carrie M
authors.initials: CM
authors.lastname: Nielson
authors.forename: Roberto
authors.initials: R
authors.lastname: Flores
authors.forename: Martha
authors.initials: M
authors.lastname: Abrahamsen
authors.forename: Mary
authors.initials: M
authors.lastname: Papenfuss
authors.forename: Robin B
authors.initials: RB
authors.lastname: Harris
authors.forename: Anna R
authors.initials: AR
authors.lastname: Giuliano
mesh_terms: D000293:Adolescent; D000328:Adult; D052685:Alphapapillomavirus / Q000145:classification* / Q000302:isolation & purification; D001130:Arizona / Q000453:epidemiology; D015331:Cohort Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008390:Markov Chains; D015999:Multivariate Analysis; D030361:Papillomavirus Infections / Q000453:epidemiology*; D011446:Prospective Studies; D012307:Risk Factors; D012725:Sexual Behavior; D012747:Sexual Partners; D055815:Young Adult