Effect of human immunodeficiency virus infection on the prevalence and incidence of vaginal intraepithelial neoplasia.

OBJECTIVE

To estimate the prevalence, incidence, and clearance of abnormal vaginal cytology and vaginal intraepithelial neoplasia (VAIN) in human immunodeficiency virus (HIV)-seropositive women.

METHODS

Pap tests were done semiannually for 335 HIV-seropositive and 75 HIV-seronegative women with prior hysterectomy in the prospective Women's Interagency HIV Study cohort. End points included abnormal Pap test results after hysterectomy and VAIN regardless of hysterectomy.

RESULTS

Over a median of 5.6 years of follow-up, vaginal Pap test results were abnormal at 1,076 (29%; 95% confidence interval [CI] 25-33%) of 3,700 visits among HIV-seropositive compared with 31 (4%; 95% CI 2-8%) of 763 visits among HIV-seronegative women (P<.001). Abnormal Pap test results included 641 atypical squamous cells of undetermined significance, 425 low-grade squamous intraepithelial lesions, and 10 high-grade squamous intraepithelial lesions in HIV-seropositive women and 28 atypical squamous cells of undetermined significance and three low-grade squamous intraepithelial lesions in HIV-seronegative women. The incidence of abnormal Pap test results after hysterectomy was 14 per 100 person-years among HIV-seropositive and two per 100 person-years among HIV-seronegative women (P<.001) and remained stable across time. The 5-year clearance rate of abnormal Pap test results was 34 per 100 person-years for HIV-seropositive and 116 per 100 person-years for HIV-seronegative women (P<.001). In multivariate regression models, women with lower CD4 counts were more likely to have and less likely to clear abnormal cytology when it occurred. The incidence of VAIN 2 or worse was 0.2 and 0.01 per 100 person-years for HIV-seropositive and HIV-seronegative women (P=.001). Two HIV-seropositive women developed stage II cancers with remission after radiotherapy.

CONCLUSION

Vaginal Pap test results are often abnormal in HIV-seropositive women. Although more common than in HIV-seronegative women, VAIN 2 or worse and especially vaginal cancers are infrequent.