Spotlight on mortality trends in liver disease

One study looked at 10-year U.S. mortality trends related to chronic liver diseases, while another assessed mortality from cirrhosis and liver cancer in the U.S. from 1999 to 2016.

Two recent studies focused on shifting trends in mortality from various liver diseases.

In the first study, researchers assessed 10-year mortality trends related to chronic liver diseases in U.S. adults ages 20 years and older. They used U.S. Census Bureau population estimates and National Center for Health Statistics mortality records to identify individuals with hepatitis C virus (HCV) infection, alcoholic liver disease, nonalcoholic fatty liver disease (NAFLD), and hepatitis B virus (HBV) infection.

Results were published online on July 15 by Gastroenterology.

HCV-related mortality increased 2.0% per year from 2007 through 2014 and decreased 6.4% per year from 2014 through 2016, when direct-acting antiviral therapies were introduced. During the same time period, age-standardized mortality increased for both alcoholic liver disease (annual percentage change, 2.3% from 2007 through 2013 and 5.5% from 2013 through 2016) and NAFLD (annual percentage change, 6.1% from 2007 through 2013 and 11.3% from 2013 through 2016). In contrast, HBV-related mortality decreased steadily from 2007 through 2016, with an average annual percentage change of −2.1% (95% CI, −3.0% to −1.2%). Minority populations had a disproportionately higher burden of mortality from chronic liver disease than whites.

The authors noted limitations of the study, such as potential misclassification of the underlying cause of mortality on death certificates and a lack of individual data. They added that the age-standardized mortality rates may not represent actual mortality rates and that documentation of NAFLD grossly underestimates the disease's true prevalence.

“It is clear that the introduction of oral, highly efficacious and well-tolerated antiviral agents has improved outcomes in patients with viral hepatitis,” they wrote. “However, future challenges with [alcoholic liver disease] and NAFLD will pose a different set of problems and will necessitate a multidisciplinary approach with a dedicated focus on minorities.”

In the second study, researchers used death certificate data from the Vital Statistics Cooperative and population data compiled from the census by the CDC's Wide-ranging Online Data for Epidemiologic Research to assess liver disease-related mortality in the U.S. from 1999 to 2016 by age group, sex, race, cause of liver disease, and geographic region. The main outcome measure was death from cirrhosis and hepatocellular carcinoma.

Results were published online on July 18 by BMJ.

From 1999 to 2016, annual deaths from cirrhosis increased by 65% to 34,174 while annual deaths from hepatocellular carcinoma doubled to 11,073. Deaths from cirrhosis began increasing from 2009 through 2016 by 3.4% per year (95% CI, 3.1% to 3.8%; P<0.001), while the age-adjusted death rate from hepatocellular carcinoma increased by 2.1% per year (95% CI, 1.9% to 2.3%; P<0.001) during the study period.

From 2009 to 2016, people ages 25 to 34 years had the highest average annual increase in cirrhosis-related mortality (10.5% [95% CI, 8.9% to 12.2%]; P<0.001), which was driven entirely by alcohol-related liver disease. During this time period, mortality due to peritonitis and sepsis in the setting of cirrhosis increased, respectively, by 6.1% per year (95% CI, 3.9% to 8.2%) and 7.1% per year (95% CI, 6.1% to 8.4%). Maryland was the only state with improvements in mortality (−1.2% per year; 95% CI, −1.7% to −0.7%), and Native Americans had the most pronounced annual increases in cirrhosis-related mortality (4.0% [95% CI, 2.2% to 5.7%]; P=0.002).

For hepatocellular carcinoma, women experienced a consistent increase in related mortality while death rates among men slowed after 2011. No state showed improvements in hepatocellular carcinoma-related mortality, and Asians and Pacific Islanders were the only subgroup who had an improvement in related mortality, with the mortality rate decreasing by 2.7% per year (95% CI, 2.2% to 3.3%; P<0.001).

The authors noted limitations of the study, including potential inaccuracies in death certificate data and the fact that they did not validate disease coding with chart review.