Cervical cancer screening uptake among HIV-positive women in Ontario, Canada: a population-based retrospective cohort study

Cervical cancer caused by oncogenic types of the human papillomavirus (HPV) is of concern among HIV-positive women due to impairment of immune responses required to control HPV infection. Our objectives were to describe patterns of cervical cancer screening using Pap cytology testing among HIV-positive women in Ontario, Canada from 2008 to 2013 and to identify factors associated with adequate screening. We conducted a retrospective, population-based cohort study among screen-eligible HIV-positive women using provincial administrative health data. We estimated annual proportions tested and reported these with 95% confidence intervals (CI). Next, using person-years as the unit of analysis, we identified factors associated with annual Pap testing using log-binomial regression. A total of 2271 women were followed over 10,697 person-years. In 2008, 34.0% (95%CI 31.1-37.0%) had a Pap test. By 2013, the proportion of HIV-positive women tested was 25.9% (95%CI 23.6-28.2%). Women who were most likely to undergo testing were younger, were immigrants from countries with generalized HIV epidemics, lived in the highest income neighbourhoods, had a female primary care physician, had two or more encounters per year with an infectious disease or internal medicine specialist, and had greater comorbidity. Nearly three in four HIV-positive women were under-screened despite all having universal insurance for medically-necessary services. Annual Pap testing decreased following the 2011-2013 release of new guidelines for a lengthened screen interval for average risk women and a billing disincentive. Clinic-based intervention such as physician alerts or reminders may be needed to improve screening coverage among HIV-positive women.