The impact of HIV infection and immunodeficiency on human papillomavirus type 6 or 11 infection and on genital warts.

Background: HIV infection and associated immunodeficiency are known to alter the course of human papillomavirus (HPV) infections and of associated diseases.

Goal: This study investigated the association between HIV and HPV and genital warts.

Study Design: HPV testing and physical examinations were performed in two large prospective studies: the Women's Interagency HIV Study (WIHS) and the HIV Epidemiology Research Study (HERS). Statistical methods incorporating dependencies of longitudinal data were used to examine the relationship between HIV and HPV and genital warts.

Results: A total of 1008 HIV-seronegative and 2930 HIV-seropositive women were enrolled in the two studies. The prevalence of HPV 6 or 11 was 5.6 times higher in HIV-seropositive women in the WIHS and 3.6 times higher in the HERS. Genital wart prevalence increased by a factor of 3.2 in the WIHS and 2.7 in the HERS in HIV-seropositive women. In the WIHS, infection with HPV type 6 or 11, in comparison with no HPV infection, was associated with odds of genital wart prevalence of 5.1 (95% CI: 2.9-8.8), 8.8 (95% CI: 6.1-12.8), and 12.8 (95% CI: 8.8-18.8) in HIV-seronegative women, HIV-seropositive women with > or =201 CD4 cells/microl, and HIV-seropositive women with < or =200 CD4 cells/microl, respectively. In the HERS, infection with HPV type 6 or 11 was associated with odds of 2.7 (95% CI: 1.6-4.6), 4.9 (95% CI: 3.2-7.7), and 5.3 (95% CI: 3.3-8.5) in these same groups. Other HPV types showed a similar dose-response relation, but of substantially lower magnitude and statistical significance.

Conclusions: HIV infection and immunodeficiency synergistically modified the relation between HPV 6 or 11 infection and genital wart prevalence.