The effect of caffeine and alcohol consumption on liver fibrosis-a study of 1045 Asian hepatitis B patients using transient elastography

Background: Role of caffeine consumption in chronic hepatitis B virus (HBV)-infected patients and the interaction with alcohol consumption is unclear. Aim: This study aimed to investigate the relationship between caffeine and alcohol consumption and liver stiffness in chronic HBV-infected patients. Methods: Chronic HBV-infected patients who underwent transient elastography examination in 2006-2008 were studied. Advanced fibrosis was defined as liver stiffness > 9 kPa for patients with normal alanine aminotransferase (ALT) or > 12 kPa for those with elevated ALT according to previous validation study. Caffeine and alcohol consumption was recorded using a standardized questionnaire. Excessive alcohol intake was defined as 30 g/day in men and 20 g/day in women. Results: The liver stiffness of 1045 patients who completed the questionnaire was 8.3 +/- 6.2 kPa. Two hundred and sixteen (20.7%) patients had advanced fibrosis. Ninety-five (19.0%) patients who drank >= 1 cup of coffee had advanced fibrosis, compared with 121 (22.2%) patients who drank <1 cup (P = 0.21). The amount of caffeine intake had positive correlation with the amount of alcohol intake (r(s) = 0.167, P < 0.001). Although 231 (22.1%) patients reported alcohol consumption, only 11 (1%) had excessive alcohol intake. The prevalence of advanced fibrosis among patients with mild to moderate alcohol intake (26, 18.8%) was comparable to that among non-drinkers (190, 21.0%) (P = 0.57). Conclusion: Caffeine intake does not affect liver stiffness in chronic HBV-infected patients. Patients who drink coffee regularly tend to drink alcohol. Most chronic HBV-infected patients do not have excessive alcohol consumption. The prevalence of advanced fibrosis among mild to moderate alcohol drinkers was low in this population.