Objectives: To study anal intraepithelial neoplasia and its associations with anal and cervical human papillomavirus (HPV), cervical neoplasia, host immune status, and demographic and behavioral risk factors in women with and at risk for HIV infection.
Design: Point-prevalence analysis nested within a prospective study of women seen at three clinical centers of the Women's Interagency HIV Study.
Methods: In 2001-2003 participants were interviewed, received a gynecological examination, anal and cervical cytology testing and, if abnormal, colposcopy-guided or anoscopy-guided biopsy of visible lesions. Exfoliated cervical and anal specimens were assessed for HPV using PCR and type-specific HPV probing. Logistic regression analyses were performed, and odds ratios (ORs) estimated risks for anal intraepithelial neoplasia.
Results: Four hundred and seventy HIV-infected and 185 HIV-uninfected women were enrolled. Low-grade anal intraepithelial neoplasia was present in 12% of HIV-infected and 5% of HIV-uninfected women. High-grade anal intraepithelial neoplasia was present in 9% of HIV-infected and 1% of HIV-uninfected women. In adjusted analyses among HIV-infected women, the risk factors for low-grade anal intraepithelial neoplasia were younger age [OR = 0.59, 95% confidence interval (CI) = 0.36-0.97], history of receptive anal intercourse (OR = 3.2, 95% CI = 1.5-6.8), anal HPV (oncogenic types only OR = 11, 95% CI = 1.2-103; oncogenic and nononcogenic types OR = 11, 95% CI = 1.3-96), and cervical HPV (oncogenic and nononcogenic types OR = 3.5, 95% CI = 1.1-11). In multivariable analyses among HIV-infected women, the only significant risk factor for high-grade anal intraepithelial neoplasia was anal HPV infection (oncogenic and nononcogenic types OR = 7.6, 95% CI = 1.5-38).
Conclusion: Even in the era of highly active antiviral therapy, the prevalence of anal intraepithelial neoplasia was 16% in HIV-infected women. After controlling for potential confounders, several risk factors for low-grade anal intraepithelial neoplasia differed from risk factors for high-grade anal intraepithelial neoplasia.