Hepatitis C virus (HCV) acquisition among HIV-positive European men who have sex with men (MSM) has steadily increased during the past 25 years, although trends vary by region, with evidence of a recent leveling-off effect in Western Europe, aidsmap reports. Researchers analyzed data from almost 6,000 MSM in 16 of the 29 CASCADE cohorts of individuals with well-established dates of when they contracted HIV. Findings were presented at the 15th European AIDS Conference in Barcelona.

Previous research has identified an emerging epidemic of sexually transmitted hep C among HIV-positive gay men in Europe, Australia and the United States. Potential risk factors include condomless anal intercourse, fisting, group sex and non-injection drug use.

The researchers used two means of analyzing their data, with the first tending to underestimate hep C incidence and the second tending to overestimate it. Method 1 looked at data on 5,953 MSM who were followed from the point when the researchers categorized them as at-risk for hep C, which was either the time they entered the study, the time the particular cohort to which they belonged instituted routine hep C testing, or when they contracted HIV. Method 2 analyzed data on 4,326 MSM who were followed after their first negative HCV test after being categorized as at-risk, as per the criteria in Method 1.

During a median four-year follow-up period, 337 people contracted hep C in the Method 1 group and 279 did so in the Method 2 group.

The rate of hep C acquisition increased steadily: according to Method 1, from 0.07 percent per year in 1990 to 1.8 percent per year in 2014; and according to Method 2, from 0.3 percent to 2.1 percent per year in the same time period.

The upward hep C incidence trend appears to be continuing in Southern and Northern Europe, while stabilizing in Western Europe.

After adjusting the data for various factors, the researchers found that men with a higher viral load were more likely to contract HIV. Other studies have found a correlation between hep C risk and CD4 count, but this one did not.

To read the aidsmap article, click here.