title: Host and viral factors in relation to clearance of human papillomavirus infection: a cohort study in Taiwan.
abstract: Human papillomavirus (HPV) persistence is essential for cervical cancer development. We accrued nested-cohort subjects from a population-based study to investigate the host and viral factors related to outcome of HPV infection. Women (age > or = 30 years old) with HPV-positive but normal cytology and negative colposcopy were invited to participate. After signing informed consent, every participant completed a structured questionnaire and had 6-monthly follow-ups of Pap smear, HPV testing and colposcopy. Total and type-specific HPV clearance rates as well as host and viral factors associated with clearance in 3-year longitudinal follow-up were analyzed. Adjusted hazard ratios (HRs) of progression to > or = cervical intraepithelial neoplasia (CIN) 2 according to baseline HPV of the women with normal cytology were calculated from national registry database. Among the 626 eligible women, 526 (median age 47, 29-75) were enrolled and 412 returned for follow-up at least once. The median follow-up of enrolled subjects was 23 months (range 6.8-39). The 3-year cumulative total HPV clearance rate was 49.0% (95% confidence interval [CI]: 43.3-54.7%). The median 3-year cumulative type-specific HPV clearance rate was 50.0% (range 0-100.0%) with a median time to clearance of 12.4 months (6.4-24.5). Older age was associated with significantly decreased total HPV clearance and decreased type-specific clearance in HPV-18 and -53, while high viral load was associated with decreased total and type-specific clearance. After adjusting confounding variables, the HR of developing > or =CIN2 in baseline HPV-positive women was 34.0-fold (95% CI: 15.5-74.7) as compared to HPV-negative women.
authors.affiliation: Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, Taiwan. sh46erry@ms6.hinet.net
authors.forename: Chyong-Huey
authors.initials: CH
authors.lastname: Lai
authors.forename: Angel
authors.initials: A
authors.lastname: Chao
authors.forename: Chee-Jen
authors.initials: CJ
authors.lastname: Chang
authors.forename: Fang-Yu
authors.initials: FY
authors.lastname: Chao
authors.forename: Huei-Jean
authors.initials: HJ
authors.lastname: Huang
authors.forename: Swei
authors.initials: S
authors.lastname: Hsueh
authors.forename: Cheng-Tao
authors.initials: CT
authors.lastname: Lin
authors.forename: Hui-Hsin
authors.initials: HH
authors.lastname: Cheng
authors.forename: Chu-Chun
authors.initials: CC
authors.lastname: Huang
authors.forename: Jung-Erh
authors.initials: JE
authors.lastname: Yang
authors.forename: Tzu-I
authors.initials: TI
authors.lastname: Wu
authors.forename: Hung-Hsueh
authors.initials: HH
authors.lastname: Chou
authors.forename: Ting-Chang
authors.initials: TC
authors.lastname: Chang
mesh_terms: D000328:Adult; D000368:Aged; D052685:Alphapapillomavirus / Q000302:isolation & purification / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D030361:Papillomavirus Infections / Q000503:physiopathology* / Q000821:virology*; D016133:Polymerase Chain Reaction; D011795:Surveys and Questionnaires; D013624:Taiwan; D002583:Uterine Cervical Neoplasms / Q000821:virology*; D019562:Viral Load