Assessing cervical intraepithelial neoplasia as an indicator disease for HIV in a low endemic setting: a population-based register study

Abstract

Objectives: To analyse whether the prevalence of undiagnosed HIV among (1) all women in Sweden and (2) migrant women, diagnosed with cervical intraepithelial neoplasia grade 2 or worse CIN2+ reaches the threshold of 0.1%, which has been suggested to be cost-effective for HIV testing. Design: Population-based register study. Setting: Counties of Stockholm and Gothenburg, Sweden, 1990–2014. Population: All women, born between 1940 and 1990, with at least one cervical cytology or histology registered in the Swedish National Cervical Screening Register (NKCx). Methods: Data were collected from the NKCx and the Swedish National HIV register. The proportion of women with undiagnosed HIV among women with CIN2+ compared with women with a normal/mildly abnormal cytology/histology was assessed. Main outcome measures: Proportion of women with undiagnosed HIV. Results: The proportion of undiagnosed HIV was higher among all women with CIN2+ than among those without CIN2+: 0.06% (95% CI 0.04–0.08) versus 0.04% (95% CI 0.04–0.04); P = 0.017). Among migrant women, the proportion of undiagnosed HIV was higher among those with CIN2+ than among those without [0.30% (95% CI 0.20–0.43) versus 0.08% (95% CI 0.07–0.10); P < 0.001] and exceeded 0.1%, suggesting the cost-effectiveness of HIV testing. Women with undiagnosed HIV at the time of CIN2+ had a significantly lower nadir CD4+ T-cell count, as a measure of immunosuppression, compared with women without CIN2+ before HIV diagnosis (median nadir CD4, 95 cells/mm3 versus 210 cells/mm3; P < 0.01). Conclusions: HIV testing should be performed in migrant women with unknown HIV status diagnosed with CIN2+. Tweetable abstract: HIV testing should be performed in migrant women with unknown HIV status diagnosed with CIN2+.