Effect of antiretroviral therapy on the incidence of cervical neoplasia among HIV-infected women: a population-based cohort study in Taiwan

Objective: Cervical cancer has been recognized as one of the AIDS-defining cancers since 1993. Receipt of HAART has been shown to reduce the risk of opportunistic infection and AIDS-defining malignancies. However, findings concerning the effect of HAART on cervical neoplasia have been inconsistent. Design: A population-based cohort design was used, in which 1360 HIV-infected women were compared to the general population (HIV-negative women). The comparison population included 358 141 HIV-negative women randomly selected from among all insured persons in Taiwan in 2000. Data from HIV-infected and uninfected women were analyzed through 2008. Methods: The age and calendar year-standardized incidence ratio was calculated to estimate the relative risk of cervical neoplasia, and Cox proportional hazards models were used to assess the effect of HAART on the incidence of cervical neoplasia. Results: The incidence of cervical neoplasia was four times higher in the HIV-infected women than in the general population [standardized incidence ratio 4.0, 95% confidence interval (CI) 2.16-6.95]. The most increased risk was noted in HIV-infected women aged 40-59 years. Receipt of HAART was associated with a significantly reduced risk of cervical neoplasia (0.20, 0.05-0.77). The most evident protective effect was noted in adherent to HAART at least 85%, and those treated with HAART for more than 3 years (0.01, 0.00-0.47). Conclusions: HIV-infected women have a substantially increased risk of cervical neoplasia. Adherent to HAART and prolonged HAART for more than 3 years may contribute to a reduction risk of cervical neoplasia.