High incidence of high grade cervical neoplasia among women with HIV in Sweden

Christina Carlander1,2, Anders Sönnerborg1, Veronica Svedhem-Johansson1, Katarina Westling1, Kristina Elfgren3, Pär Sparen4
Affiliates: 1Department of Medicine, Huddinge, Karolinska Institutet, 2Centre for Clinical Research, County of Västmanland Hospital, Västerås, 3Department of Obstetrics and Gynecology, Karolinska Hospital, 4Department of Medical Epidemiology and Biostatistics, Karolinska Institutet

Objectives
To assess the incidence of high-grade cervical intraepithelial neoplasia and invasive cervical cancer (CIN 2+), in a cohort of HIV-infected women, compared to HIV-negative women.

Methods
Our cohort consisted of HIV-infected women (n= 1154) identified from the Swedish national HIV register InfCare HIV and HIV-negative women (n= 257 743) identified from the Swedish Population Register, frequency matched on region of birth (as categorized by UNAIDS) and age. Data was collected between 1993 and 2011 by linking our cohort with the Swedish National Quality Register of Cervical Cancer Prevention (NQRCP), collecting all cytological and histological results. Participants were followed from study entry until whichever came first of CIN 2+, emigration, death or 31 December 2011. The cumulative incidence (CuI) and hazard ratio (HR) of CIN 2+ was assessed.

Results
The CuI of CIN 2+ after 10 years of follow up was 15,5 % for HIV-infected women and 2 % for HIV-negative women. After five years of follow up HIV-infected women born in Eastern Europe and Asia, Sub-Saharan Africa and Sweden had a CuI of 15 %, 9 % and 7 % respectively. After adjusting for age and region of birth, HIV-infected women had a 5 times higher risk of CIN2+ (HR=5; 95% CI 4-7) compared with HIV-negative women. The highest risk was seen among HIV infected immigrants. Those born in Sub-Saharan Africa had an additional risk of 2,5 (HR 2,5; 95 % CI 1,6-4,0), and those born in Eastern Europe or Asia had an additional risk of 2,4 (HR 2,4; 95 % CI 1,4-4,1). The risk of CIN2+ increased significantly with immunosuppression (CD4<200 at inclusion, p=0,0062).

Conclusion
Our results confirm the high incidence of CIN 2+ among HIV-infected women. Early HIV-diagnosis and attendance to cervical screening, with special focus on immigrants, is of crucial importance to minimize the incidence of CIN 2+.