HPV co-factors related to the development of cervical cancer: results from a population-based study in Costa Rica
Hildesheim, A.; Herrero, R.; Castle, P.E.; Wacholder, S.; Bratti, M.C.; Sherman, M.E.; Lorincz, A.T.; Burk, R.D.; Morales, J.; Rodriguez, A.C.; Helgesen, K.; Alfaro, M.; Hutchinson, M.; Balmaceda, I.; Greenberg, M.; Schiffman, M.
British Journal of Cancer 84(9): 1219-1226
2001
ISSN/ISBN: 0007-0920 PMID: 11336474 DOI: 10.1054/bjoc.2001.1779Document Number: 261343
We examined factors associated with high-grade squamous intraepithelial lesions (HSIL) and cervical cancer among human papillomavirus (HPV)-infected women in a prevalent case-control study conducted within a population-based cohort of 10 077 women in Costa Rica. We compared 146 women with HPV-positive HSIL or cancer (HSIL/CA) against 843 HPV-positive women without evidence of HSIL/CA. Subjects completed a risk factor questionnaire. We evaluated the associations between exposures and HSIL/CA among women positive for any HPV and restricted to those positive for high-risk HPV types. Risk of HSIL/CA increased with increasing number of live births (P(trend)= 0.04). Women who smoked 6+ cigarettes/day had a RR for HSIL/CA of 2.7 (95% CI = 1.1-6.7) compared to non-smokers. Current use of barrier contraceptives was associated with a reduction in risk of HSIL/CA (RR = 0.39; 95% CI = 0.16-0.96). Sexual behaviour and a self-reported history of sexually transmitted diseases (STDs) other than HPV were not associated with HSIL/CA. Oral contraceptive use was associated with HSIL/CA among women with <3 pregnancies. Effects were similar in analysis restricted to women positive for high-risk HPV types. Among women positive for high-risk HPV types, 44% of HSIL/CA could be attributed to multiparity (>/=3 pregnancies) and/or smoking. Among HPV-positive women, multiparity and smoking are risk factors for HSIL/CA. Oral contraceptive use may be associated with HSIL/CA in subgroups of women.