Prevalence and risk factors for anal squamous intraepithelial lesions in women

Abstract

Background: Anal cancers are thought to arise from squamous intraepithelial lesions in the anal canal, and women infected with human immunodeficiency virus-1 (HIV) may be at higher risk of anal cancer. Our aim was to determine the prevalence of human papillomavirus (HPV)-related abnormalities of the anal canal in women and to characterize risk factors for these lesions. Methods: We evaluated HPV-related abnormalities in 251 HIV-positive and in 68 HIV-negative women. We completed physical examinations and obtained questionnaire data on medical history and relevant sexual practices. Univariate and adjusted relative risks (RRs) and 95% confidence intervals (CIs) were computed using the Mantel-Haenszel procedure and regression techniques. All statistical tests were two-sided. Results: Abnormal anal cytology, including atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesions, or high-grade squamous intraepithelial lesions (HSILs), was diagnosed in 26% of HIV-positive and in 8% of HIV-negative women. HSILs were detected by histology or cytology in 6% of HIV-positive and in 2% of HIV-negative women. HIV-positive women showed increased risk of anal disease as the CD4 count decreased (P