Prevalence of and Risk Factors for Anal Human Papillomavirus in Heterosexual Men
AuthorNyitray, Alan Gaspar
AdvisorHarris, Robin B.
Committee ChairHarris, Robin B.
MetadataShow full item record
PublisherThe University of Arizona.
RightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
AbstractIntroduction: The incidence of anal cancer, whose primary cause is human papillomavirus (HPV) infection, has increased in United States (US) men almost three-fold in three decades; however, little is known about the epidemiology of anal HPV, especially in heterosexual men. Furthermore, advancements in knowledge about the epidemiology of anal HPV may be hampered by measurement error in the collection of sexual behavior data. Methods: From two US cities, behavioral data and anal biological specimens were collected from 253 men who acknowledged sexual intercourse with a woman in the previous year. PCR and genotyping were used to assess the presence of HPV DNA. In addition, two HPV questionnaires were assessed for test-retest reliability: the first was a self-administered questionnaire associated with the collection of the biological specimens while the second was a computer-assisted self-interview (CASI) with 1069 men in Brazil, Mexico, and the US. Results: Based on DNA analysis, overall anal HPV prevalence was 24.8% in 222 men who acknowledged no prior sexual intercourse with men. Risk factors independently associated with anal HPV were lifetime number of female sexual partners and frequency of sex with females in the past month. Based on kappa and intraclass correlation coefficients (ICC), both HPV questionnaires were found to be highly reliable with low refusal rates; however, three discrete measures in the multi-national interview asking for the number of sexual partners had lower reliability. The ICC of these questions increased to greater than or equal to 0.79 when a small number of extreme outliers (less than or equal to 3) were removed. Predictors of unreliable reporting were age and lifetime number of female sexual partners while years of education was inversely associated with unreliable reporting. Discussion: These results suggest anal HPV is common in heterosexual men. Risk factors associated with anal HPV did not explain how HPV was transmitted to the anal region. Both instruments used to collect sexual behavior data were highly reliable including the CASI instrument used in three culturally and linguistically distinct countries; however, caution is warranted with discrete measures that ask participants to report the number of sexual partners.