Investigators in the US have found a high
incidence of hepatitis C virus (HCV) infection among HIV-positive gay men. Annual
incidence was 1.6% – the highest ever seen
in research involving HIV-positive gay men in the United States – among
patients receiving care at the Fenway Institute in Boston. The study is
published in the online edition of Clinical
“This is the highest HCV incidence reported
in the United States among HIV-infected MSM [men who have sex with men] to date
and suggests that incident HCV is common in this population,” comment the
authors. The study’s findings also showed that infections were most likely due
to sexual risk behaviour or non-injecting drug use.
Hepatitis C is a blood-borne infection and
injecting drug use is a major risk factor for infection.
However, there is accumulating evidence of
hepatitis C transmissions not linked to injecting drug use among HIV-positive
gay men. These infections appear to be due to traumatic sexual practices such
as fisting and non-injecting drug use, especially in the context of group sex.
Much of this evidence comes from Europe. However,
hepatitis C infections in the absence of injecting drug use have also been
reported among HIV-positive gay men in New York and other US cities. But low
rates of baseline screening have made it difficult to accurately assess
incidence of hepatitis C among HIV-infected gay men in the US.
The Fenway Institute in Boston provides
care to a large number of HIV-positive gay men. The prevalence of self-reported
injecting drug use among these patients is low at below 3%. Researchers at the
Institute therefore believed their patients offered “a unique opportunity to
explore the epidemiology of HCV among a population of patients previously
perceived to be at low risk”.
Doctors from the Institute designed a
retrospective study involving all HIV-infected men who had at least two
appointments at the clinic between June 2008 and June 2009. The authors extracted
data from patient records to determine prevalence and incidence of hepatitis C
infection between 1997 and 2009. They also examined the factors associated with
both prevalent and incident infections.
A total of 1160 HIV-positive gay men were
included in the study, and 1059 (91%) had at least one hepatitis C antibody
test. Men who reported sex with men as their only risk factor for infection
with HIV were more likely to be screened for hepatitis C than men who reported
both sex with another man and injecting drug use (p < 0.01). Men with a
detectable viral load were also more likely to have a hepatitis C antibody test
than patients with an undetectable viral load (p = 0.01).
Initial screening showed that 64 (6%) of
men were co-infected with hepatitis C virus.
Of the 995 men who were initially negative
for hepatitis C, 616 (62%) did not have a repeat test. Participants were more
likely to have a follow-up screen for the infection if their viral load was
detectable (p < 0.01).
“This low rate of repeat…testing may in
part be due to healthcare provider perceptions that their patients are at low
risk for HCV,” suggest the authors.
The 379 men who had a repeat test
contributed 1408 person-years of follow-up. In all, 6% became infected with
hepatitis C, providing an incidence of 1.6 per 100 person-years.
Injecting drug use was reported by a third
of those with prevalent and incident hepatitis C. Non-injecting drug use was
reported by 46% of men, and 16% of individuals denied any substance use. Cocaine
was the most widely used non-injected drug. The majority of co-infected patients
had a history of at least one sexually transmitted infection.
Compared to participants with hepatitis C at
baseline, men with incident infections were younger (37 vs 44 years, p <
0.01) and were more likely to have a history of sexually transmitted infections
(87 vs 64%, p = 0.04).
“Our findings support the growing body of
evidence that the epidemiology of HCV infection may be changing among
HIV-infected MSN in the United States,” comment the authors. “In the absence of
IDU [injecting drug use], high risk sexual behaviors and non-injecting drug use appear to play an
important role in transmission.”
A liver biopsy was performed on 26 co-infected
patients. The results showed that 50% had no or very mild fibrosis and 31% had
more advanced liver damage or cirrhosis.
Seven men with incident infections
underwent hepatitis C therapy and six achieved a sustained virological
response. A successful treatment outcome was also achieved by seven of the 15
men with prevalent infection who underwent therapy.
The authors conclude that HIV-positive gay
men should be tested annually for hepatitis C. They also recommend that
“HIV-infected MSM who use recreational drugs and/or engage in unprotected sex
should receive education and services related to sexual risk
reduction…preventative interventions are crucial to stemming the ongoing spread