Higher Rates of Anal Vs Oral HPV Infection in HIV+ Baltimore Group

Anal human papillomavirus (HPV) prevalence, incidence, and persistence were significantly greater than oral HPV prevalence, incidence, and persistence in a study of 404 HIV-positive people in Baltimore, Maryland. People with HIV infection run a greater risk of HPV infection than people without HIV. Prevalence of anal versus oral HPV is greater in people with HIV, but the reasons for this difference are poorly understood.

To address this question, researchers collected oral rinse and anal swab samples twice a year from 404 HIV-positive adults in Baltimore. They tested the samples for 37 HPV types and used adjusted models to explore risk factors for HPV persistence.

Anal versus oral HPV rates were significantly greater for prevalence (84% versus 28%), incidence (145 versus 31 per 1000 person-months), and 12-month persistence (54% versus 29%) (P < 0.001 for each comparison). Heterosexual men had a lower anal HPV incidence than men who have sex with men or women, but heterosexual men had a higher incidence of oral HPV than the other groups (P < 0.001 for interaction).

Statistical analysis identified two independent predictors for HPV persistence at the following adjusted hazard ratios (aHR) (and 95% confidence intervals):

• Prevalent versus incident HPV: aHR 4.0 (3.5 to 4.8)

• Anal versus oral HPV: aHR 1.5 (1.2 to 1.9)

The researchers propose that "the higher incidence and persistence of anal vs oral HPV infections likely contributes to the higher burden of anal as compared to oral HPV-associated cancers in HIV-infected individuals."

Source: Daniel C. Beachler, Gypsyamber D'Souza, Elizabeth A. Sugar, Wiehong Xiao, Maura L. Gillison. Natural history of anal vs oral HPV infection in HIV-infected men and women. Journal of Infectious Diseases. 2013; 208: 330-399.

Written by Mark Mascolini on behalf of the International AIDS Society