UC San Diego

The study aim is to compare anal intraepithelial neoplasia (AIN) progression and regression rates in a cytology inception cohort to estimates based on the subcohort referred for ≥1 high-resolution anoscopies (HRAs).A cytology-based retrospective cohort was assembled including the anal cytology histories and invasive anal cancer (IAC) outcomes of all HIV-infected adults under care between 2001 and 2012. A 3-state Markov model (400, and to have HSIL at baseline and thereafter. They also had more anal cytology examinations (median 6 vs 3) and longer follow-up (median 5.5 vs 3.6 years). State transition rates were overestimated in the HRA subcohort relative to inception cohort, but the degree of discordance varied by transition: for