Role of active and passive smoking in high-risk human papillomavirus infection and cervical intraepithelial neoplasia grade 2 or worse

Abstract

Objective: We performed a pooled analysis to examine cigarette smoking and household passive smoke exposure in relation to the risk of human papillomavirus (HPV) infection and cervical intraepithelial neoplasia grade 2+ (CIN2+).

Methods: Data were pooled from 12 cross-sectional studies for cervical cancer screenings from 10 provinces of China in 1999-2007. A total of 16,422 women were analyzed, along with 2,392 high-risk-HPV (hr-HPV) positive women and 381 CIN2+ cases. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression models controlling for sexual and non-sexual confounding factors.

Results: There was an excess risk between active smoking and hr-HPV infection and CIN2+. Adjusted OR for ever smokers vs. never smokers was 1.45 (95% CI=1.10-1.91), for hr-HPV infection and 1.89 (95% CI=1.03-3.44), for CIN2+. Passive smoking had a slightly increased risk on the hr-HPV infection with adjusted OR 1.11 (1.00-1.24), but no statistical association was observed between passive smoke exposure and CIN2+. Compared with the neither active nor passive smokers, both active and passive smokers had a 1.57-fold (95% CI=1.14-2.15) increased risk of HPV infection and a 1.99-fold (95% CI=1.02-3.88) risk of CIN2+.

Conclusion: Our large multi-center cross-sectional study found active smoking could increase the risk of overall hr-HPV infection and CIN2+ adjusted by passive smoking and other factors. Passive smoking mildly increased the risk of HPV infection but not the CIN2+. An interaction existed between passive tobacco exposure and active smoking for hr-HPV infection and the CIN2+.

Keywords: Cervical Intraepithelial Neoplasia; Chinese; Infection; Papillomaviridae; Smoking; Tobacco Smoke Pollution; Women.

Fig. 1

Adjusted ORs and 95% CIs for the relationships between active smoking and risk of HPV infection (A) and CIN2+ (B) in the individual and pooled studies. (A) Logistic models were adjusted by age, area, education, age at menarche, age at sexual debut, sexual partners, menopause, parity, intrauterine device, oral contraceptives, condoms, sterilization, husband's affair, active, and passive smoking mutually; (B) Logistic-models were additionally adjusted for HPV infection. CI, confidence interval; CIN2+, cervical intraepithelial neoplasia grade 2 or worse; HPV, human papillomavirus; IARC, International Agency for Research on Cancer; OR, odds ratio; SPOCCS, Shanxi Province Cervical Cancer Screening Study; START, Screening Technologies to Advance Rapid Testing.

Fig. 2

Adjusted ORs and 95% CIs for the relationships between passive smoking and risk of HPV infection (A) and CIN2+ (B) in the individual and pooled studies. (A) Logistic models were adjusted by age, area, education, age at menarche, age at sexual debut, sexual partners, menopause, parity, intrauterine device, oral contraceptives, condoms, sterilization, husband's affair, active, and passive smoking mutually; (B) Logistic-models were additionally adjusted for HPV infection. CI, confidence interval; CIN2+, cervical intraepithelial neoplasia grade 2 or worse; HPV, human papillomavirus; IARC, International Agency for Research on Cancer; OR, odds ratio; SPOCCS, Shanxi Province Cervical Cancer Screening Study; START, Screening Technologies to Advance Rapid Testing.