Risk factors for human papillomavirus and cervical precancerous lesions, and the role of concurrent HIV-1 infection

Objectives: To identify risk factors for human papillomavirus (HPV) infecti on and squamous intraepithelial lesions (SIL) of the cervix, and to measure the impact of concurrent HIV-1 infection. Methods: Women were studied at a family planning clinic in Nairobi, Kenya. Demographic and historical infor mation was obtained using a semi-structured questionnaire and specimens wer e collected for sexually transmitted diseases (STDs), HPV, cervical cytolog y, and HIV-1 testing. Results: HPV was detected in 87 of 513 women (17%), i ncluding 81 (93%) oncogenic types (16, 18, 31, 33 and others) and six (7%) non-oncogenic types (6 and 11). HIV-1 prevalence was 10%. HPV detection was associated with HIV-1 infection [adjusted odds ratio (aOR) 3.9, 95% confid ence interval (CI), 2.0-7.7], sexual behavior indicators including the numb er of sex partners and inflammatory STDs, as well as the number of pregnanc ies (0 or 1 vs. greater than or equal to 3, aOR 0.4; 95% CI, 0.2-0.9). SIL was detected in 61 women (11.9%), including 28 (46%) with low-grade lesions (LSIL) and 33 (54%) with high-grade lesions (HSIL). HPV infection was stro ngly associated with HSIL (OR 14.9; 95% CI, 6.8-32.8). In a multivariate mo del predictors of HSIL included HIV-1 serpositivity (aOR 4.8; 95% CI, 1.8-1 2.4), the number of lifetime sex partners (0-1 vs. greater than or equal to 4; aOR 3.8; 95% CI, 1.1-13.5), and older age (< 26 vs. > 30; OR 3.9; 95% C I, 1.1-13.6). An analysis stratified by HIV-1 showed a stronger association between HPV and HSIL in HIV-1 negative women (OR 17.0; 95% CI, 6.4-46.3) t hen in HIV-1 positive women (OR 4.5; 95% CI, 0.8-27.4). Conclusions: Our re sults indicate that HSIL and even invasive cancer are highly prevalent in t his setting of women on reproductive age considered to be at low risk for S TDs, suggesting that routine Pap smear screening may save lives. (C) 1999 I nternational Federation of Gynecology and Obstetrics.