Abstract 551: Human papillomavirus (HPV) infection characteristics in a cohort of men who have sex with men (MSM) during long-term follow-up

Abstract

Abstract Purpose: To describe sociodemographic, HIV and HPV infection characteristics in MACS men. Background: HPV-associated invasive anal cancer (IAC) is a health crisis for gay, bisexual, transgender and other MSM. MSM show 20-40 fold higher risk for IAC, especially within the context of HIV and since the introduction of combined antiretroviral therapy (CART) (1-4). Experts classify high-risk HPVs as having sufficient (Group 1) or limited (Group 2) evidence of causality for cervical cancer. The prevalence of these HPVs in MSM may inform risk for cancer. Methods: For 1262 MACS men evaluated at visits 56-58, Dacron swab specimens were tested for HPV using the Linear Array assay (Roche Diagnostic Laboratories, Pleasanton, CA). HPVs were classified as high-risk Groups 1 (HPV16/18/31/33/35/39/45/51/52/56/58/59) and 2 (HPV26/30/34/53/66/67/68/69/70/73/82), and low-risk HPVs (HPV6/11/40/42/54/56/61/62/64/70/71/72/82/83/84/IS39/CP6108). Descriptive and tabular analyses were used to explore the data. Poisson regression with robust error variance analyses were used to estimate prevalence ratios (PR, (95% confidence intervals)) comparing HPV groupings in both univariate and multivariate models using the SAS 9.2 GENMOD procedure (SAS Institute, Cary, North Carolina, USA). Final models included age and race, period-specific self-reported number of sexual partnerships, HIV-infection status, and CD4+ count (cell/mm3) among HIV-infected participants. Results: Participants are best described as older (µ=55 (9.4), M=55.6), and although Whites comprised >50% of both groups, HIV-infected men were >2 times as likely as uninfected men to report being Black, 25% vs. 10%. On average, the prevalence of all HPVs was 1.35-1.91 fold higher among HIV-infected than -uninfected men. Trend analyses showed CD4+ cell count was inversely associated with HPV Group 2 prevalence alone (p<0.0001). Only the number of receptive anal sex partners reported in the 24 months preceding the HPV test visit consistently predicted higher prevalence of Group 1 and 2 HPVs. However, for low-risk HPVs, the lifetime number of male sex partners reported at MACS visit 1, partners reported between visit 1 and the visit 24 months before HPV testing, and those recorded during the last 24 months were all significantly and positively associated with higher prevalence of low-risk HPVs (p=<0.05), e.g., 30+ vs. <30 lifetime male partners at visit 1, PR=1.20 (1.06, 1.37); receptive anal intercourse partners during the last 24 mo prior to HPV testing, 1-3 and >4 vs. 0: PR=1.13 (1.01, 1.26) and 1.16 (1.05, 1.30), respectively. Conclusions: HIV-infected MSM demonstrated a higher prevalence of all HPV groups evaluated and while number of sex partners were important for predicting the prevalence of low-risk HPVs, only the most recent receptive anal intercourse partnerships predicted prevalence of Group 1 and 2 HPVs. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 551. doi:1538-7445.AM2012-551