Hepatitis C does not raise risk of heart disease or cancers in people with HIV

Hepatitis C coinfection does not increase the risk of cardiovascular disease or non-AIDS cancers in people with HIV, an analysis of the large Eurosida cohort published in Clinical Infectious Diseases has found.

Although the long-term impact of hepatitis C virus (HCV) infection on the risk of end-stage liver disease in people with HIV is well established, the long-term impact of HCV coinfection on risks of cardiovascular disease or non-AIDS-defining cancers is unclear. The risks of cardiovascular disease or cancers such as non-Hodgkin lymphoma, pancreatic cancer or cholangiocarcinoma are elevated in people with HCV mono-infection but the effect of HCV infection on these risks in people with HIV is unknown.

Furthermore, studies which have identified increased risks of some conditions in people with HCV have been carried out in varying populations with relatively small sample sizes. The Eurosida cohort is a large cohort that collects comprehensive information on people in HIV care in Europe and Argentina.

The analysis looked at the risk of cardiovascular disease, non-AIDS malignancies and end-stage liver disease in people with HIV and HCV antibodies, compared to people with HIV alone.

The analysis distinguished between four groups of people with HCV antibodies: people who had cleared HCV spontaneously, people with untreated chronic HCV infection, people cured of HCV by any treatment and people with chronic HCV who had not been cured by treatment.

The analysis included all patients with known HCV antibody and RNA status followed in participating cohorts from January 2001, a total of 16,818 people. Sixty-two percent were HCV antibody-negative, 5.5% had cleared HCV spontaneously, 22.3% were chronically infected with HCV but untreated, 4.9% had been cured of HCV infection and 5.2% had experienced failure of HCV treatment.

Approximately three-quarters (74%) were male, 85% were white and 83% had some exposure to antiretroviral therapy, 67.8% having an HIV viral load below 500 copies/ml (undetectable) at the beginning of the follow-up period.

People who inject drugs made up 25.7% of the entire cohort but formed the majority in all HCV antibody-positive groups.

Among those with chronic HCV infection, advanced liver fibrosis (stages 3 or 4) was most common in those who had experienced previous treatment failure (18.2%) or those cured of HCV infection (19%).

Participants were followed for a median of 8.3 years. During the follow-up period the most common clinical events were non-AIDS defining cancers (902 cases, most commonly anal cancer, comprising 15.9% of all malignancies, and lung cancer, comprising 10.6%) and cardiovascular events (887 cases, most frequently invasive cardiovascular procedure (39.6%) or stroke (28.1%)).

The incidence rate of cardiovascular disease was 6.4 cases per 1,000 person-years of follow-up and incidence of CVD was slightly higher in HCV-negative people and in people who had cleared hepatitis C spontaneously.

The incidence rate of non-AIDS-defining cancers was 6.5 per 1,000 person-years of follow-up with no significant difference between the groups in incidence rate.

The incidence rate of end-stage liver disease was 3.1 per 1,000 person-years of follow-up. The highest rates of end-stage liver disease occurred in untreated (9.6 per 1000 p.y.) and treatment failure groups (9.9 per 1000 p.y.) (both p< 0.0001).

People cured of hepatitis C by treatment did not have significantly lower rates of cardiovascular disease, or of heart attack or stroke when the results were broken down by CVD event. The same was true for non-AIDS-defining malignancies, and the investigators also found that the type of HCV treatment that people had received did not affect these outcomes, regardless of whether treatment resulted in a cure or not.