Anal human papillomavirus infection among HIV-infected and uninfected men who have sex with men in Beijing, China.

BACKGROUND: In light of China's unique ethnic and sociocultural context, and a marked rise in HIV prevalence among MSM, it is important to determine prevalence, genotypes and predictors of anal human papillomavirus (HPV) among HIV-infected and uninfected men who have sex with men (MSM) in Beijing, China.

METHODS: In 2010-2011, we recruited MSM (age range 18-61; median 28 years) through peer volunteers, and collected demographic/behavioral information via interviewer-administrated questionnaires. Trained health workers collected anal swabs for HPV genotyping by PCR and blood samples for HIV/syphilis serologies.

RESULTS: We obtained anal specimens from 212 HIV-infected and 459 HIV-uninfected participants. Among HIV-infected MSM, 82.1% were HPV-infected vs. 57.5% in HIV-uninfected (p<0.01). HIV-infected men had the greatest likelihood of multiple types: 17.9% uninfected; 36.3% with one type; 36.8% with 2-3; 9.0% with ≥4. Oncogenic HPV prevalence was higher among HIV- infected (61.3%) than uninfected participants (39.7%; p<0.01). HIV-uninfected MSM reporting always using condoms during insertive anal intercourse (past 6 months) were less likely to be HPV-infected (OR=0.49, 95%CI: 0.31-0.77). Among HIV-uninfected MSM, HPV infection was associated with unprotected receptive anal intercourse (past 6 months; OR=1.92, 95%CI: 1.19-3.11) and being forced to have sex (previous year; OR=3.32, 95%CI: 1.10-10.0). Multivariable logistic analysis among HIV infected MSM suggested that unprotected oral intercourse (past 6 months) was associated with HPV (adjusted OR=2.12, 95%CI: 1.00-4.48). Syphilis occurred in 55.8% of HIV-infected/HPV-infected, 50.0% of HIV-infected/HPV-uninfected, 19.6% of HIV-uninfected/HPV-infected, and 13.0% of HIV-uninfected/HPV-uninfected MSM.

CONCLUSIONS: HPV anal infections were more common among HIV-infected than uninfected MSM in China, including oncogenic and multiple types. Unprotected oral and receptive anal sex were was independently associated with HPV infection. Promotion of safer sex and HPV vaccination is strongly recommended among MSM.