When hepatitis C (HCV) is acquired in patients with HIV infection, CD4 T-cell counts temporarily decline after HCV seroconversion, regardless of the duration of HIV or whether the patient is on combination antiretroviral therapy (cART), according to study findings published in AIDS.
Co-infection with HCV in men who have HIV and have sex with men (MSM) has increased in prevalence. In this demographic, HIV infection often precedes HCV infection, which is different from what has been demonstrated in early studies of HIV/HCV co-infection in individuals who inject drugs. Most studies on HCV/HIV co-infection have not accounted for the order and duration of the 2 infections, and in this study the researchers assessed the effect of incident HCV infection and its timing relative to HIV seroconversion and the effect on subsequent CD4 counts in MSM, as well as HIV-RNA viral load trajectories.
Study participants were drawn from 17 cohorts within the CASCADE Collaboration and all had well-estimated dates of HIV seroconversion. HCV co-infected MSM were matched to MSM who only had HIV by HIV infection duration and cART use. A total of 214 ART-naïve co-infected MSM men, 147 of whom were on cART, were matched to 5384 and 3954 matched controls, respectively. The timing of HCV seroconversion relative to HIV seroconversion appeared to have no obvious effect on viral load or CD4 trajectory. During the initial 2- to 3-year period following HCV seroconversion, CD4 counts were lower in the co-infected cohort but transitioned after that and became comparable to HIV mono-infection in MSM. In the ART-naïve population, viral load levels were lower during the first 2 years following HCV seroconversion and lower or comparable to the viral load in patients who were HIV mono-infected but were higher afterwards. HCV had no significant effect on a detectable viral load in patients on cART.
“Continued HCV prevention, testing and treatment are warranted in this group,” wrote the researchers. “The short- and long-term clinical implications of our findings still need to be further elucidated.”
van Santen DK, van der Helm JJ, Touloumi G, et al. Effect of incident hepatitis C infection on CD4 count and HIV RNA trajectories based on a multinational HIV seroconversion cohort [published online October 15, 2018]. AIDS. doi:10.1097/QAD.0000000000002040