Background: Anal cancer rates are higher for human immunodeficiency virus (HIV)-infected adults than for uninfected adults. Limited published data exist characterizing the incidence of precursor lesions detected by anal cytology.
Methods: The Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy was a prospective cohort of 700 HIV-infected participants in 4 US cities. At baseline and annually thereafter, each participant completed a behavioral questionnaire, and healthcare professionals collected anorectal swabs for cytologic examination and human papillomavirus (HPV) detection and genotyping.
Results: Among 243 participants with negative baseline results of anal cytology, 37% developed abnormal cytology findings (incidence rate, 13.9 cases/100 person-years of follow-up; 95% confidence interval [CI], 11.3-16.9) over a median follow-up duration of 2.1 years. Rates among men having sex with men, among women, and among men having sex with women were 17.9 cases/person-years of follow-up (95% CI, 13.9-22.7), 9.4 cases/person-years of follow-up (95% CI, 5.6-14.9), and 8.9 cases/person-years of follow-up (95% CI, 4.8-15.6), respectively. In multivariable analysis, the number of persistent high-risk HPV types (adjusted hazard ratio [aHR], 1.17; 95% CI, 1.01-1.36), persistent high-risk HPV types except 16 or 18 (aHR, 2.46; 95% CI, 1.31-4.60), and persistent types 16 or 18 (aHR, 3.90; 95% CI, 1.78-8.54) remained associated with incident abnormalities.
Conclusions: The incidence of abnormal anal cytology findings was high and more likely to develop among persons with persistent high-risk HPV.
Keywords: HIV; HPV; abnormal anal cytology; incidence; persistence.
Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.