Curing hepatitis C virus (HCV) in those coinfected with HIV is most likely to reduce the risk of death among those who have advanced fibrosis. Consequently, researchers stress the importance of treating HCV among this population.

Looking to identify modifiable risk factors associated with a reduced risk of death among HIV/HCV-coinfected individuals, researchers analyzed data from the Canadian Coinfection Cohort, which includes 1,695 people with both viruses receiving medical care at 18 clinics across

Canada. This represents about a quarter of all coinfected Canadians.

Findings were presented at the 9th International AIDS Society Conference on HIV Science in Paris (IAS 2017).

The investigators looked at two periods, April 2003 through December 2008 and January 2009 through July 2016, as well as two age brackets, 20- to 49-year-olds and those 50 and older. Ultimately, the analysis included 1,477 individuals for whom birth dates and follow-up dates were recorded. The median follow-up time was 4.1 years.

Eighty percent of the group in the final analysis reported a history of injection drug use, 49 percent reported alcohol use and more than 90 percent reported current smoking upon entering the study group. Eighty-one percent had not been treated for hep C upon entering the cohort. About one in five had moderate to severe fibrosis of the liver. Eighty-four percent were on antiretroviral (ARV) treatment for HIV, and 64 percent had a fully suppressed virus.

During the first time period, 2003 to 2008, 6 percent of those in the younger age bracket and 3 percent of those in the older age bracket were cured of hep C. During the 2009 to 2016 period, a respective 22 percent and 23 percent of the age brackets were cured of the virus.

Fourteen percent (203) of the cohort members died during the study’s follow-up, for a death rate of 3.05 percent per year. The median age at death was 47. Twenty-one percent of the deaths were a result of end-stage liver disease (ESLD), 17 percent were driven by smoking, 16 percent were related to a drug overdose, 22 resulted from other causes, including infections, cancer, suicide, trauma or AIDS and 25 percent were a result of unknown causes. Deaths resulting from ESLD appeared to decline over time only among those 50 to 80 years old.

After adjusting the data for various factors, the researchers found that compared with those in the 2003 to 2008 period, those in the 2009 to 2016 period had a 59 percent lower risk of death from smoking, a 69 percent lower risk of death from a drug overdose and a 35 percent lower risk of death from ESLD. However, the drop in ESLD-related death risk was not statistically significant, meaning the difference could have been driven by chance.

During the study, cohort members were about five times more likely to die of ESLD if they had moderate to severe fibrosis and three times more likely to die of the condition if they had a CD4 count below 350.