Participating men had a median age of 31 years (interquartile range: 23-40) and were recruited from Brazil (35%), Mexico (33%), and the United States (32%). Overall, 2,650 (67%) men were positive for any HPV, 1,183 (30%) positive for oncogenic HPV, 898 (23%) positive for non-oncogenic HPV only, and 1,146 (29%) positive for multiple HPV infections.
Population characteristics are presented by CT infection and HSV-2 serostatus in . In total, 64 (1.6%) men were infected with CT at baseline. CT infection was most common (2.4% CT-infected) in the youngest age group (18-30 years) (P<0.001). CT prevalence was highest in men recruited from Brazil (2.3%) followed by Mexico (1.3%) and the United States (1.2%) (P=0.038). A higher number of recent female sexual partners during the past three to six months (P=0.026), and having a partner diagnosed with genital warts during the past six months (P=0.028) were significantly associated with CT infection.
Baseline characteristics and sexual history of the study population (recruited July 2005-September 2009) by Chlamydia trachomatis infection and herpes simplex virus type 2 serostatus.
In total, 811 (20.4%) men had antibodies against HSV-2. HSV-2 seroprevalence increased with age (P<0.001), with men from Brazil having the highest HSV-2 seroprevalence (38.4%). HSV-2 seroprevalence was associated with marital status (P<0.001), education (P<0.001), smoking (P=0.045), and circumcision (P<0.001). HSV-2 seroprevalence was highest in men who reported ≥20 lifetime female sexual partners (P<0.001) and increased with lifetime number of male anal sexual partners (P<0.001). All other sexual behavior variables were associated with HSV-2 serostatus, except condom use during vaginal or anal sex during the past 3-6 months and number of recent female sexual partners.
shows the prevalence of HPV infection by CT infection status and HSV-2 serostatus. HPV prevalence was higher in CT-infected men compared to CT-negative men for the following HPV outcomes: any HPV; oncogenic HPV; ≥1 HPV genotype; multiple HPV genotypes; HPV vaccine types; HPV 11, and HPV 18 (P≤0.05). HPV prevalence was higher in HSV-2 seropositive men than in HSV-2 seronegative men for the following HPV outcomes: any HPV; oncogenic HPV; non-oncogenic HPV only; ≥1 HPV genotype; and multiple HPV genotypes (P≤0.05).
Prevalence of human papillomavirus infection in the HIM study population by Chlamydia trachomatis infection and herpes simplex virus type 2 serostatus
Bivariable and multivariable analyses (approach 1) examining associations between the four HPV outcomes and the two main exposures (CT infection and HSV-2 serostatus) are presented in . In bivariable and multivariable analyses, CT infection was independently associated with any HPV (aOR 2.19, 95%CI: 1.13-4.24), oncogenic HPV (aOR 3.10, 95%CI: 1.53-6.28), and multiple HPV infections (aOR 3.43, 95%CI: 1.69-6.95). In the case of non-oncogenic HPV only, the association was marginally significant in the bivariable analysis (crude OR 2.16, 95%CI: 1.00-4.68, P=0.050) and was not significant in the multivariable analysis (aOR 1.95, 95%CI: 0.88-4.32, P=0.101). HSV-2 seropositivity was significantly associated with any HPV (aOR 1.25, 95%CI: 1.02-1.52), non-oncogenic HPV only (aOR 1.38, 95%CI: 1.08-1.75), and multiple HPV infections (aOR 1.33, 95%CI: 1.06-1.68). However, in the case of oncogenic HPV, HSV-2 serostatus was significantly associated in the bivariable analysis (crude OR 1.52, 95%CI: 1.24-1.85) and marginally significant in multivariable analyses (aOR 1.26, 95%CI: 1.00-1.59, P=0.051).
Association between HPV infection and Chlamydia trachomatis infection and, HPV infection and herpes simplex virus type 2 serostatus: bivariable and multivariable analyses
Multivariable logistic regression analyses were performed in two additional ways (see methods). In approach 2, addition of the covariates mentioned above did not improve the model based on the likelihood ratio test, and did not significantly alter the association between either CT infection and HSV-2 serostatus with the four HPV outcomes by >5%. Using approach 3, the association between multiple HPV infections and HSV-2 seropositivity was not significant (aOR 1.25; 95%CI 0.99-1.57; P=0.056); all other results were comparable.
Stratified analyses for the association between CT infection and the four HPV outcomes are presented in . A significant association for all outcomes was found in the group that reported ≥2 RSP, except for the association between CT infection and non-oncogenic HPV only (aOR 3.22, 95%CI: 0.86 - 12.06). Stratified analyses by LSP for the association between HSV-2 serostatus and the four HPV outcomes are shown in . HSV-2 serostatus was significantly associated with the four HPV outcomes among men reporting 0-5 LSP, but this association was weaker among men reporting 6-14 LSP, and absent among men reporting ≥15 LSP. The same trend was observed for the three other HPV outcomes.
a: Association between HPV infection and CT infection stratified by recent number sexual partners during the pas 3-6 months
In additional stratified analyses by country CT was positively associated with HPV in each country; however, the strength of these associations was highest in the US, followed by Mexico, and weakest in Brazil. HSV-2 was positively associated with HPV in each country (data not shown).