The Effect of Caffeine and Alcohol Consumption on Liver Fibrosis

A Study of 1045 Asian Hepatitis B Patients Using Transient Elastography

Arlinking Ong; Vincent Wai-SunWong; Grace Lai-Hung Wong; Henry Lik-Yuen Chan


Liver International. 2011;31(7):1047-1053. 

In This Article


Study Population

We prospectively recruited chronic HBV-infected patients regardless of the disease activity for transient elastography. We received referrals from all primary care and hospital clinics in Hong Kong from July 2006 to February 2008.[12] Chronic HBV infection was diagnosed by positive serology tests for serum HBsAg for at least 6 months. We excluded patients with evidence of other chronic liver disease by screening with antibody against hepatitis C virus, antinuclear antibody, antismooth muscle antibody, antimitochondrial antibody, serum ceruloplasmin, transferrin saturation and ferritin.

From April to May 2008, patients from the original cohort were phone-interviewed with a verbal consent for this study. Questions concerning their alcohol and caffeine consumption (days per week of consumption and amount per day) in the previous year were asked from a standardized questionnaire. Patients who refused to give verbal consent for the phone-interview were not included in this study.

Clinical Evaluation

All patients received comprehensive clinical and laboratory assessment at the time of transient elastography. Serum HBV DNA levels were measured by the TaqMan real-time polymerase chain reaction assay with a range of detection from 100 to 109 copies/ml.[13] Anthropometric parameters including body weight, body height, hip circumference and waist circumference were measured. Body mass index (BMI) was calculated as weight (kg) divided by height (m) squared. Overweight was defined as BMI≥23 kg/m2, and obesity as BMI≥25 kg/m2 according to the Asian and Chinese criteria.[14] We defined moderate and severe obesity as BMI≥28 kg/m2 M and ≥30 kg/m2 respectively. Excessive alcohol intake was defined as >30 g/day in men and >20 g/day in women.[15]

Liver Stiffness Measurement by Transient Elastography

Transient elastography (FibroScan®, Echosens, Paris, France) is one of the new noninvasive modality to evaluate liver fibrosis by measuring liver stiffness. It uses an ultrasound-based technique to measure the speed of propagation of the shear wave through the liver. It can assess approximately 1/500 of the liver's total mass thus reducing the sampling error. Transient elastography has been shown to accurately predict histological advanced fibrosis in different liver diseases.[16–21]

Liver stiffness measurement (LSM) was performed using transient elastography according to the instructions of the manufacturer. Details of the technical background and examination procedure was described previously.[22] Officially trained operators who had performed at least 50 measurements prior this study were responsible to perform the LSM for the patients who had kept fast for at least 8 h. The LSM was considered reliable only if 10 successful acquisitions were obtained, an interquartile range (IQR)/LSM of ≤30% and the success rate was ≥60%. Liver stiffness was expressed in kPa. We defined advanced fibrosis as liver stiffness >9 kPa for those with normal ALT or >12 kPa for those with elevated ALT (F3 fibrosis on histology).[23,24]

Hui's Index

Hui's index was a non-invasive model comprising of BMI, platelet count, serum albumin and total bilirubin [predictive probabilities=exp(3.148+0.167 × BMI+0.088 × bilirubin [μM]−0.151 × albumin [g/L]−0.019 × platelet [109/L])/(1+exp(3.148+0.167 × BMI+0.088 × bilirubin [μM]−0.151 × albumin [g/L]−0.019 × platelet [109/L]))] to predict significant fibrosis (F2 fibrosis on histology).[25] Among 235 chronic hepatitis B patients with liver biopsy, at a cutoff value of 0.15, the sensitivity, specificity, positive and negative predictive values for significant fibrosis were 93, 49, 41 and 95% respectively.

Phone-interview and Questionnaire

A structured questionnaire interview was conducted over the phone to collect data on alcohol and caffeine intake. Participants were specifically asked about the average quantity and frequency of beer, wine, or liquor consumption to estimate the amount of alcohol consumption. The average quantity and frequency of consumption of coffee (regular, instant, ground and decaffeinated), tea (any kind), cola-type soda (regular or decaffeinated) and chocolate (including chocolate milk) was also enquired to estimate the amount of caffeine consumption. Effect of alcohol and caffeine consumption was analyzed with respect to the severity of liver fibrosis as assessed by transient elastography, Hui's Index and other clinical and biochemical parameters

Statistical Analyses

Total caffeine consumption (mg/day) was estimated by summing caffeine from regular coffee (137 mg per cup), regular tea (47 mg per cup), regular and diet cola-type soda (46 mg per bottle or can) and chocolate (7 mg per serving).[26] As for the coffee cup equivalent, the total caffeine consumption per day was divided by 137 (Table 1). Continuous variables were expressed in mean ± standard deviation or median (IQR) as appropriate. Qualitative and quantitative differences between subgroups were analyzed using χ2 or Fisher's exact test for categorical parameters as appropriate, and Student's t-test or Mann–Whitney test for continuous parameters as appropriate. Logistic regression analyses were performed to determine if caffeine and alcohol consumption was associated with liver fibrosis. The multivariate adjusted logistic regression model included covariates that were included in univariate analysis. Spearman's rank correlation was used to correlate caffeine and alcohol intake. All statistical tests were two-sided. Statistical significance was taken as P<0.05. Statistical analysis was performed by Statistical Package for Social Science (SPSS version 17.0, Chicago, IL, USA).


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.