November 6, 2008 (San Francisco, California) — Increased coffee consumption may slow the progression of liver damage caused by hepatitis C virus infection, researchers reported in a poster here at The Liver Meeting 2008: 59th Annual Meeting of the American Association for the Study of Liver Diseases (AASLD). Patients who self-reported drinking 3 or more cups of coffee per day were less likely to have liver disease progression than those who drank less coffee daily.
“In population studies, coffee intake has been inversely associated with cirrhosis, chronic liver disease, and hepatocellular carcinoma. But, no studies have examined the relationship between coffee consumption and progression of advanced liver disease,” wrote Neal D. Freedman, MD, of the National Cancer Institute at the National Institutes of Health, Department of Health and Human Services, in Rockville, Maryland, and colleagues.
To study this relationship, Freedman analyzed patient questionnaire data about food frequency, including coffee and tea consumption, from the 3.5-year HALT-C randomized trial of 1050 hepatitis C patients at Ishak stage 3 or higher who were unresponsive to standard drug therapies. Some patients in the HALT-C trial received no treatment, and others received 90 µg/week of pegylated interferon alfa-2a.
Of the 808 patients who responded to the questionnaire at baseline, 711 drank zero to 2 cups of coffee a day, and 97 drank 3 or more cups of coffee daily. Those who drank the most coffee also consumed the most alcohol and cigarettes. These coffee drinkers, however, had healthier livers than the other participants, with less steatosis (evaluated by biopsy) and lower bilirubin levels, α-fetoprotein levels, and aspartate aminotransferase/alanine aminotransferase ratios (P < .05).
Liver disease had progressed in 208 patients at the 13-month follow-up, but outcome rates decreased from 10.4/100 person-years (no coffee daily) to 6.0/100 person-years (3 or more cups of coffee daily; P = 0.002). The hazard ratio for coffee consumption ranged from 1.21 (0.81 – 1.79) for no coffee daily to 0.53 (0.29 – 0.95) for 3 or more cups daily (95% confidence intervals; P = .0005). The results show that “coffee consumption may slow the progression of fibrotic liver disease,” Freedman wrote in the abstract.
“This is an observational study,” Freedman told Medscape Gastroenterology, “so it may be that coffee is a marker for some other activity,” he said. “It may be that people who are feeling sicker don’t drink as much coffee.” He looked at tea drinkers as well but did not find an association between tea consumption and liver disease, he said.
The questionnaire did not ask about the strength of the coffee, what people put in their coffee, or whether people drank caffeinated or decaffeinated coffee, Freedman said. About 85% of coffee consumed nationally is caffeinated. Freedman said that hypotheses about what part of coffee is beneficial to the liver are “pretty speculative” although “maybe the best data is for caffeine.” Of the 1000-plus compounds in coffee, several of them may be influencing liver disease, he said.
One advantage of the study was its focus on “the natural history of clinically significant disease progression, which other studies have not been able to do,” said Freedman’s colleague James Everhart, MD, of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, in Bethesda, Maryland. The study also benefited from a homogenous population. “They all started off with liver disease, so we knew they had liver disease and were able to then look at progression of liver disease from that point on,” he told Medscape Gastroenterology.
Actual coffee consumption can be difficult to measure. Samir Rouabhia, MD, from the University Hospital Center Touhami Benflis, Department of Internal Medicine, in Batna, Algeria, said that people tend to drink coffee unevenly. “One day you take one cup and one day you take three cups,” he told Medscape Gastroenterology, which makes it difficult to measure coffee’s effect on the liver. He also pointed out that it’s unclear how the coffee was prepared and how strong it was.
Drs. Freedman, Everhart, and Rouabhia have disclosed no relevant financial relationships. The study received no commercial support.
The Liver Meeting 2008: 59th Annual Meeting of the American Association for the Study of Liver Diseases: Abstract 1778. Presented November 4, 2008.
Pearls for Practice
- Although patients with hepatitis C virus infection who drank the most coffee (3 or more cups daily) also consumed the most alcohol and cigarettes, they had slower progression of fibrotic liver disease. Hazard ratio for progression of liver disease was 1.21 for no coffee daily to 0.53 for 3 or more cups daily (95% confidence intervals; P = .0005).
- Those who consumed 3 or more cups of coffee daily had less evidence of liver damage than did other participants with hepatitis C virus infection, with less steatosis on biopsy, and significantly lower bilirubin levels, α-fetoprotein levels, and aspartate aminotransferase/alanine aminotransferase ratios.