Men with penile HPV infection have an increased risk of acquiring HIV

Men with penile human papillomavirus (HPV) infection have an increased risk of acquiring HIV, investigators report in the online edition of AIDS. This increase in risk was irrespective of circumcision status.

“Our results indicate that HPV infection is an important risk factor for HIV acquisition in men that needs to be explored further and accounted for in HIV-prevention studies,” comment the authors.

It has already been shown that cervical HPV is associated with increased HIV risk for women. Investigators wished to see if penile HPV infection similarly increased the risk of HIV acquisition for men, and if this risk was modified by circumcision status. They therefore designed a prospective cohort study involving approximately 2500 men in Kisumu, Kenya, who were enrolled in the randomised-controlled trial designed to evaluate the impact of circumcision status on HIV risk.

All the men were HIV negative at baseline and aged between 19 and 24 years. Every six months, the study participants had penile swabs to check for HPV infection and they were also screened for HIV.

Over a median of 30 months of follow-up, 61 men (2.4%) acquired HIV. Men randomised to be circumcised were significantly less likely to acquire HIV than men who remained uncircumcised.

Penile HPV infection was present in 61% of the men who seroconverted for HIV and 46% were infected with HPV types associated with a high risk of ano-genital cancers.

The authors’ first analysis showed that men infected with any HPV type had over twice the risk of acquiring HIV compared to HPV-uninfected men (HR = 2.55; 95% CI, 1.51-4.32). Men infected with high-risk HPV types (HR = 2.74; 95% CI, 1.66-4.79) were also over twice as likely to become infected with HIV compared to men who were HPV negative.

Circumcision status did not significantly alter these findings.

After controlling for potential confounders, there was an association just short of significance between penile infection with any HPV type (aHR = 1.72; 95% CI, 0.94-3.15) and penile infection with high-risk HPV types (aHR = 1.92; 95% CI, 0.96-3.87) and acquisition of HIV.

The more HPV types detected on the penis of an individual, the higher his risk of acquiring HIV. Each additional type increased the risk of HIV acquisition by over a quarter (aHR = 1.27; 95% CI, 1.09-1.48). Men with three or more HPV types had over three times the HIV risk compared to HPV-uninfected individuals.

Men infected with HPV types 16/18 only (both of which are covered by two licensed HPV vaccines) had the highest risk of acquiring HIV. However, the authors were unsure if this finding was of significance to HPV vaccination strategies. They explain: “Men with only HPV-16/18 were twice as likely to acquire HIV infection compared to men who were HIV-negative. But these men represent a minority of our population. Most HIV seroconverters had only non-16/18 genotype infections or had HPV-16/18 in addition to other HPV types.”

An increased risk of HIV was observed in men who had cleared all HPV infections, had persistent HPV infections, or who had both cleared and persistent infections.

“Incidence of HIV was highest among men with persistent and/or recently cleared HPV infections,” conclude the authors. “We found no clear evidence that circumcision modifies the association between penile HPV infection and the risk of HIV acquisition.”