Incidence of Cervical Squamous Intraepithelial Lesions Associated With HIV Serostatus, CD4 Cell Counts, and Human Papillomavirus Test Results

Abstract

Recent cervical cancer screening guidelines state that the interval between screenings can be safely extended to 3 years in healthy women 30 years or older who have normal cytology results and have negative test results for oncogenic human papillomavirus (HPV) DNA. To determine the incidence of squamous intraepithelial lesions (SILs) in HIV-seropositive women with normal cytology results, by baseline HPV DNA results. Participants were HIV-seropositive (n = 855; mean age, 36 years) and HIV-seronegative (n = 343; mean age, 34 years) US women with normal baseline cervical cytology who were enrolled in the Women's Interagency HIV Study (WIHS), a large, multi-institutional prospective cohort study. Since their recruitment during 1994-1995, WIHS participants have been followed up semi-annually with repeated Pap smears for a median of 7 years. The cumulative incidence of any SIL and high-grade SIL or cancer (HSIL+) was estimated according to baseline HPV DNA results, stratified by HIV serostatus and CD4 T-cell count. Development of any SIL in women with negative HPV results (both oncogenic and nononcogenic) at 2 years was as follows: in HIV-seropositive women with CD4 counts less than 200/microL, 9% (95% CI, 1%-18%); with CD4 counts between 200/muL and 500/microL, 9% (95% CI, 4%-13%); and with CD4 counts greater than 500/microL, 4% (95% CI, 1%-7%). The CIs for these estimates overlapped with those for HIV-seronegative women with normal baseline cytology who were HPV-negative (3%; 95% CI, 1%-5%), indicating that at 2 years, there were no large absolute differences in the cumulative incidence of any SIL between groups. Furthermore, no HPV-negative participants in any group developed HSIL+ lesions within 3 years. Multivariate Cox models showed that on a relative scale, the incidence of any SIL among HIV-seropositive women with CD4 counts greater than 500/microL (hazard ratio [HR], 1.2; 95% CI, 0.5-3.0), but not those with CD4 counts less than or equal to 500/microL (HR, 2.9; 95% CI, 1.2-7.1), was similar to that in HIV-seronegative women. The similar low cumulative incidence of any SIL among HIV-seronegative and HIV-seropositive women with CD4 counts greater than 500/microL and who had normal cervical cytology and HPV-negative test results suggests that similar cervical cancer screening practices may be applicable to both groups, although this strategy warrants evaluation in an appropriate clinical trial.