Effects of polycyclic aromatic hydrocarbons exposure on prognosis of high risk human papillomavirus infection: a prospective cohort study

Abstract

Objective: To investigate the effects of polycyclic aromatic hydrocarbons (PAHs) exposure on the prognosis of high risk human papillomavirus (HR-HPV) infection. Methods: In this prospective study, 564 patients with low-grade cervical intraepithelial neoplasia confirmed by pathology were selected from the natural cohort population established by our research group in Shanxi province in 2014. Based on the baseline data of demographic characteristics and factors related to HPV infection, the concentrations of 1-hydroxypyrene in urine samples of the patients were determined by high performance liquid chromatography to define the exposure level of PAHs. At baseline survey and follow-up after 24 months, flow-through hybridization was used to detect HPV infection types, and to evaluate the prognosis of HR-HPV (persistent infection, negative conversion, positive conversion and persistent negative status). Results: Of the 564 subjects, 483 completed the follow-up, with a follow-up rate of 85.6% (483/564). Among them, the persistent infection rate was 52.4% (75/143), the persistent homotype infection rate was 35.7% (51/143), the negative conversion rate was 47.6% (68/143), the positive conversion rate was 19.7% (67/340), and the persistent negative rate was 80.3% (273/340). The follow-up results showed that the persistent infection rate (aRR=3.22, 95%CI: 1.85-5.62) and positive conversion rate (aRR=2.84, 95%CI: 1.64-4.94) of HR-HPV in high PAHs exposure group were higher than those in low PAHs exposure group, while the persistent negative rate (aRR=0.55, 95% CI: 0.43-0.70) of HR-HPV in high PAHs exposure group were lower than those in low PAHs exposure group. Based on restrictive cubic spline analysis, the results showed that the effects of PAHs exposure on persistent HR-HPV infection and persistent homotype infection showed an ascending linear dose-response relationship, while on HR-HPV positive conversion and persistent negative status showed an ascending and declining nonlinear dose-response relationship respectively (P<0.01). Conclusions: High PAHs exposure could promote persistent HR-HPV infection and persistent homotypic infection. Reducing PAHs exposure might conducive to HR-HPV continuous negative maintenance. Active prevention and control of PAHs exposure is of great significance to prevent HR-HPV infection and persistent infection.