HCV-Associated Mortality Continues Decline in US, but Gaps Remain

Although the overall mortality rate for hepatitis C virus (HCV) has declined, clinicians and public health specialists will have to focus on individuated factors to address populations with lingering barriers to treatment.

A study comparing national trends with various subpopulations in the United States has identified disproportionately higher HCV-associated mortality in the southern and western regions and Washington DC, along with non-Hispanic American Indians/Alaska Natives, non-Hispanic blacks, and Baby Boomers.

The research, published in Clinical Infectious Diseases, found that although HCV-associated mortality has declined on a national scale, there are still disparities regionally and demographically in outcomes. Led by investigators from the US Centers for Disease Control and Prevention, the study sought to analyze HCV-associated morality rates and counts across 10 regions, 50 states, and Washington DC. The investigators also sought to describe the epidemiology of deaths through demographic traits, and to see whether the mortality rate decline seen from 2015 to 2016 continued through 2017.

Kathleen Ly, epidemiologist in CDC's Division of Viral Hepatitis and a study author, told Contagion that "in 2017, more than 17,000 people in the U.S. died from a disease that has an effective cure. Each death from this disease is a preventable tragedy."

To identify HCV-associated deaths in the targeted areas, the authors calculated age-adjusted HCV-associated death rates. Then, the study team compared death rate ratios for the target regions and states with the national rate to describe changes between 2016 and 2017. Death rates were calculated by dividing HCV-associated deaths by the census population and adjusting to the age distribution of the 2000 US standard population using the direct method.

The study results indicated that in 2017, there were 17,253 HCV-associated deaths. This represents a 6.56% decline from 2016; however, rates remained high among the previously mentioned subpopulations. It was also identified that the number of HCV infections is growing among young adults, linked to an increase in injection drug use related to the opioid crisis. The opioid crisis has precipitated a general rise in infectious disease, with HCV incidence closely linked to increases in injection drug use and accounting for more deaths than all other reportable infections in the US combined.

Study investigators explained that “with changing HCV-associated death rate trends, it is imperative to examine the distribution of mortality at a finer geographic level” in order to “mitigate that burden particularly in jurisdictions with greater or increasing HCV-associated death rates.”

When analyzed in terms of race/ethnicity, HCV-associated death rates were highest for non-Hispanic American Indians/Alaska Natives (AIANs) at 10.24%, followed by non-Hispanic blacks at 7.03%, and Hispanics at 5.29%. Rates for whites in Washington DC, the Dallas region, and the San Francisco region were significantly higher than the non-Hispanic white national average.

The higher HCV-associated death rate in AIANs was speculated to be tied to comorbidities with alcohol-related conditions and general challenges accessing testing, treatment, and care in rural or economically neglected areas.

Ly pointed out a limitation of death certificate data used to collect information on HCV-associated morality, noting that "death certificate data do not include information on indicators such as income and health insurance status, so we were unable to measure associations between these socio-economic status factors."

National HCV infection prevalence was 2.4 times higher in whites than blacks, but the HCV-associated death rate for blacks was higher. This disparity was in part explained by reference to the fact that African Americans have a less favorable immune response to the pre-direct acting antiviral (DAA) regimen interferon and ribavirin. Additionally, previous studies have found an association between DAA non-initiation and black race/ethnicity compared to white race/ethnicity.

Study investigators linked challenges facing the Baby Boomer population to restrictive reimbursement policies set forth by insurance plans and payers. For example, authors noted that “Medicaid required moderate-to-severe liver damage before qualifying for treatment in all twelve jurisdictions that were identified…as having the highest death rates with the exception of Texas.”

In 2016, the World Health Organization outlined a timeline to achieve global elimination of HCV by 2030. While experts have argued this ambitious goal is, in fact, achievable, this study demonstrates that special care will need to be taken in addressing complex barriers to treatment among subpopulations with disproportionate rates of HCV-associated mortality.