Research has shown that highly active antiretroviral therapy (HAART) can decrease the risk of acquiring hepatitis B virus (HBV), regardless of a patient’s HIV infection status. Other studies have shown that men who have sex with men (MSM) are at increased risk for HBV infection. However, data on the effects of HAART on incident HBV infection in MSM who are infected and not infected with HIV are limited. “Little is known about how the rates of incident HBV infection changed from the era prior to HAART availability through the present day,” says Chloe Thio, MD.

A Closer Look

For a study published in Annals of Internal Medicine, Dr. Thio and colleagues sought to determine predictors of incident HBV infection in nearly 2,400 MSM in the Multicenter AIDS Cohort Study. Participants were not infected with HBV at baseline but had HIV or were at risk for contracting the virus. “The study was designed to understand more about how HAART affected new hepatitis B infection,” adds Dr. Thio. “Enrollment began in 1984, 12 years before HAART became available.”

During more than 25,000 person-years of follow-up, 244 incident HBV infections occurred. Overall, unadjusted incidence rates of HBV infection were higher in HIV-infected participants than in those without HIV; rates were significantly lower during the HAART era than during the pre-HARRT era among those with and without HIV. “Most importantly, effective HAART that reduced HIV RNA levels to less than 400 copies/mL was protective against incident HBV infection independent of whether an anti-HBV drug was part of the HAART regimen,” says Dr Thio.

During a median follow-up of 9.5 years, MSM with HIV who received effective HAART were 80% less likely to become infected with HBV than cohorts who did not receive HAART or had detectable HIV virus while on HAART. HAART that did not achieve HIV RNA levels of 400 copies/mL or lower was not protective against HBV infection. The following were independently associated with higher HBV infection incidence:

  • Age younger than 40.
  • More than one recent sexual partner.
  • HIV infection.

The researchers also found that the percent of MSM with HIV who had received more than one of the three HBV vaccine doses increased throughout the study period, rising from 41% to 67% among men with HIV and increasing from 28% to 58% among men without HIV. “Overall, only about 60% of men in the study had received the HBV vaccine by 2013,” Dr. Thio says. “We need to do a better job vaccinating MSM against HBV because the vaccine is highly effective.”

Important Implications

Dr. Thio notes that HBV vaccination rates may be low due to the level of patient engagement required to complete the three-dose series. “Our study only asked patients if they had received at least one dose,” she explains. “The rate of MSM with HIV who have received all three doses is likely lower. Physicians should increase awareness among all their patients, especially MSM, of HBV and the fact that it can become a chronic infection. Clinicians should ask their MSM patients if they have been vaccinated against HBV or have been infected with it in the past. If neither has occurred, these patients should be vaccinated. Because sex with multiple partners is a risk factor for contracting HBV infection, MSM should also be counseled on the important of using protection during sex.”


Chloe Thio, MD, has indicated to Physician’s Weekly that he has no financial interests to disclose.