There has been a rapid rise in deaths due to liver disease in the US since 2009, especially in young people, driven predominantly by alcohol use, say researchers in The BMJ today.
They also point out that the worsening trends began after 2008, a year marked by the global financial crisis and a subsequent economic recession in the US, which may explain some of the results.
Cirrhosis is scarring of the liver caused by long-term damage, which can lead to fatal conditions such as liver cancer and liver failure. The most common causes are drinking too much alcohol over many years, being infected with hepatitis C, or having a build-up of excess fat in the liver (known as non-alcoholic fatty liver disease).
Cirrhosis and liver cancer carry personal and financial burdens for patients, their families, and society, so prevention and early treatment is cost-effective. However, data to guide allocation of resources and preventive efforts are limited, particularly in different groups or regions of the country.
So Elliot Tapper and Neehar Parikh at University of Michigan and VA Ann Arbor Healthcare System set out to investigate deaths relating to liver disease among US adults.
They examined death certificate data for nearly 600,000 adults from the Vital Statistics Cooperative and population data from the US Census Bureau between 1999 and 2016.
They looked at trends in deaths related to cirrhosis and liver cancer based on age group, sex, race and place of residence. They also looked at trends due to specific complications of cirrhosis, causes other than cirrhosis, and alcohol use disorder.
After taking account of several factors that could have influenced the results, the researchers found that deaths due to cirrhosis increased by 65% (from 20,661 in 1999 to 34,174 in 2016) and deaths due to liver cancer doubled (from 5,112 in 1999 to 11,073 in 2016).
Men had twice as many cirrhosis related deaths and four times as many liver cancer related deaths than women.
During 2009-16, people aged 25-34 experienced the highest average annual increase in cirrhosis deaths (10.5%), driven predominantly by alcohol related liver disease. In contrast, liver cancer deaths decreased in younger people (under 55 years) and continued to increase in those over 55 years old.
Over the same period, white Americans, Native Americans, and Hispanic Americans experienced the greatest increase in deaths from cirrhosis.
States in the Western and Southern US experienced the fastest rise in cirrhosis and liver cancer related deaths: Kentucky 6.8%, New Mexico 6% and Arkansas 5.7%. Only one state in the north east region, Maryland, experienced a significant annual decrease in cirrhosis related deaths (-1.2%).
The authors suggest that the 2008 global financial crisis and the subsequent economic recession in the US may have played a part in their findings. For example, unemployment is linked with alcohol abuse in young men, but not women, which may explain why death rates were highest for young men.
This is an observational study, so no firm conclusions can be drawn about cause and effect, and the researchers outline some study limitations. For example, death certificate data may be inaccurate.
Nevertheless, they say their study shows that specific demographic groups and states are disproportionately affected by trends in cirrhosis and liver cancer related deaths and more detailed data are required.
"These data underscore gaps in care and opportunities for prevention" they conclude.