Hormonal contraceptive use and smoking as risk factors for high-grade cervical intraepithelial neoplasia in unvaccinated women aged 30–44 years: A case-control study in New South Wales, Australia. (August 2018)

• Record Type: Journal Article
• Authors: Xu, Huilan; Egger, Sam; Velentzis, Louiza S.; O'Connell, Dianne L.; Banks, Emily; Darlington-Brown, Jessica; Canfell, Karen; Sitas, Freddy
• Is Part Of: Cancer epidemiology. Volume 55(2018:Aug.)
• Page Start: 162
• Page End: 169
• Publication Date: 2018-08
• Subjects: CIN cervical intraepithelial neoplasia -- HPV human papillomavirus -- IARC International Agency for Research on Cancer -- IUD intra-uterine device -- LSIL low grade squamous intraepithelial lesion -- NSW New South Wales -- PTR Pap Test Register; Cervical intraepithelial neoplasia -- Human papillomavirus -- Hormonal contraceptives -- Smoking -- High grade -- Pre-cancer; Cancer -- Epidemiology -- Periodicals; Cancer -- Prevention -- Periodicals; Cancer -- Diagnosis -- Periodicals; Carcinogenesis -- Periodicals; 616.994005
• DOI: 10.1016/j.canep.2018.05.013
• Languages: English
• ISSNs: 1877-7821

Abstract

Highlights: The majority of adult women around the world have not been vaccinated against HPV. Understanding cofactors for the development of high grade cervical lesions is important. We found current users of hormonal contraceptives to be at increased risk of high grade lesions. The risk increases with increasing duration of hormonal contraceptive use. Current smokers of ≥5 cigarettes/day had at increased risk of developing CIN 2/3. The risk of CIN2/3 decreases in ex-smokers with increasing time since quitting. Abstract: Background: Human papillomavirus (HPV) vaccines protect against HPV types 16/18, but do not eliminate the need to detect pre-cancerous lesions. Australian women vaccinated as teenage girls are now entering their mid-thirties. Since other oncogenic HPV types have been shown to be more prevalent in women ≥30 years old, understanding high grade cervical lesions in older women is still important. Hormonal contraceptives (HC) and smoking are recognised cofactors for the development of pre-malignant lesions. Methods: 886 cases with cervical intraepithelial neoplasia (CIN) 2/3 and 3636 controls with normal cytology were recruited from the Pap Test Register of NSW, Australia. All women were aged 30–44 years. Conditional logistic regression was used to quantify the relationship of HC and smoking to CIN 2/3 adjusted for various factors. Results: Current-users of HC were at higher risk for CIN 2/3 than never-users [odds ratio (OR) = 1.50, 95%CI = 1.03–2.17] and risk increased with increasing duration of use [ORs:1.13 (0.73–1.75), 1.51 (1.00–2.72), 1.82 (1.22–2.72) for <10, 10–14, ≥15 years of use; p-trend = 0.04]. Ex-users had risks similar to never-users (OR 1.08, 95%CI = 0.75–1.57) regardless of duration of use. Current smoking was significantly associated with CIN 2/3 (OR = 1.43, 95%CI = 1.14–1.80) and risk increased with increasing number of cigarettes/day (p-trend = 0.02). Among ex-smokers, the risk of CIN 2/3 decreased with increasing time since quitting (p-trend = 0.04). Conclusions: In this benchmark study, current, long term users of HC and current smokers of ≥5 cigarettes/day were each at increased risk of developing CIN 2/3. Findings support smoking cessation in relation to decreasing the risk of pre-cancerous lesions and reinforce the continuing need for cervical screening for cancer prevention in vaccinated and unvaccinated populations.