Aspirin and some over the counter pain relievers significantly reduce the risk of liver cancer and chronic liver disease, according to a large new study by the National Cancer Institute.
Researchers surveyed over 300,000 men and women, aged 50 to 71, who reported on their use of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs). Aspirin has long been known to reduce the risk of heart attack and stroke, but this was the first large scale study to look at its impact on liver disease and liver cancer. It is being published in the Journal of the National Cancer Institute.
Aspirin users were 41% less likely to develop hepatocellular carcinoma (liver cancer) and 45% less likely to die from chronic liver disease than non-users.
People who used non-aspirin NSAID’s were 26% less likely to die from chronic liver disease (CLD), but did not have a lower incidence of liver cancer (HCC).
“Aspirin, in particular, when used exclusively or with other non-aspirin NSAIDs showed a consistent protective effect related to both HCC incidence and CLD mortality, regardless of the frequency or exclusivity of use,” wrote lead author Vikrant Sahasrabuddhe, of the Division of Cancer Epidemiology and Genetics at the National Cancer Institute.
“These associations are prominent with the use of aspirin, and if confirmed, might open new vistas for chemoprevention of hepatocellular carcinoma and chronic liver disease.”
Enthusiasm for the study was tempered in an accompanying editorial published in the same journal.
“The hype is building,” wrote Drs. Isra Levy and Carolyn Pim from the Department of Epidemiology and Community Medicine at the University of Ottawa, who called the findings a “promising observation” but cautioned that there was not enough evidence to justify the regular use of aspirin, even for prevention of cardiovascular disease.
“NSAIDs, including aspirin, are well known to increase the risk of bleeding, especially gastrointestinal bleeding and it behooves those making individual clinical or population-level policy recommendations to carefully consider any potential benefit in light of the concomitant potential for inadvertent harm,” they wrote.
Levy and Pim cited a 1999 study that estimated there were 16,500 deaths each year from aspirin and NSAID-related bleeding. However, the author of that study no longer considers the results valid.
“That’s an old number. That’s history,” Gurkirpal Singh, MD, an adjunct clinical professor of medicine at Stanford University told MedPage Today and the Milwaukee Journal Sentinal.
The Centers for Disease Control and Prevention says only about 3,400 people died from gastrointestinal bleeding in 2008. That number includes all gastrointestinal bleeding deaths, not just those caused by aspirin and other NSAIDs.
The 300,000 participants in the National Cancer Institute study were followed for ten to 12 years. During that time, 250 people developed hepatocellular carcinoma and 428 died from liver disease. It is not known how many died from gastrointestinal bleeding.
While the study found an association between aspirin use and a lower risk for liver problems, it did not prove cause-and-effect. Previous studies have suggested that aspirin lowers the risk of some cancers by reducing inflammation.