Effect of alcohol consumption on liver stiffness measured by transient elastography.

AIM To determine the evolution of transient elastography (TE) in patients with alcoholic liver disease according to alcohol cessation or continuation. METHODS We retrospectively selected in our local database all patients who had two TE between June 2005 and November 2010 with chronic alcohol excessive consumption and excluded those with associated cause of liver disease. TE was performed at least one week apart by senior operator. TE examinations with less than ten successful measures or with an interquartile range above 30% were excluded. We retrospectively reviewed file of all patients to include only patient followed up by trained addictologist and for which definite information on alcohol consumption was available. Concomitant biological parameters [aspartate amino transferase (AST), alanine amino transferase and gamma-glutamyl transpeptidase (GGT)] within 4 wk of initial and final TE were recorded. Putative fibrosis score according to initial and final TE were determined with available cut-off for alcoholic liver disease and hepatitis C. Initial and final putative fibrosis score were compared according to alcohol consumption during follow-up. RESULTS During the study period 572 patients had TE examination for alcoholic liver disease and 79 of them had at least two examinations. Thirty-seven patients met our criteria with a median follow-up of 32.5 wk. At the end of the study, 13 (35%) were abstinent, and 24 (65%) relapsers. Eight patients had liver biopsy during follow-up. TE decreased significantly during follow-up in 85% of abstinent patients [median (range): -4.9 (-6.1,-1.9)], leading to a modification of the putative fibrosis stage in 28%-71% of patient according to different cut-off value. In relapsers TE increased in 45% and decreased in 54% of patient. There was no statistical difference between initial and final TE in relapsers. In the overall population, using 22.6 kPa as cut-off for cirrhosis, 4 patients had cirrhosis at initial TE and 3 patients had cirrhosis at final TE. Using 19.5 kPa as cut-off for cirrhosis, 7 patients had cirrhosis at initial TE and 5 patients had cirrhosis at final TE. Using 12.5 kPa as cut-off for cirrhosis, 16 patients had cirrhosis at initial TE and 15 patients had cirrhosis at final TE. Evolution of biological data was in accordance with the relapse or abstinent status: abstinence ratio (duration of abstinence/duration follow-up) was correlated with AST ratio (r = -0.465, P = 0.007) and GGT ratio (r = -0.662, P < 0.0001). GGT was correlated with initial (r = 0.488, P = 0.002) and final TE (r = 0.49, P < 0.005). Final TE was correlated with AST (r = 0.362, P < 0.05). Correlation between TE ratio and AST ratio (r = 0.44, P = 0.01) revealed that TE varied proportionally to AST for all patients irrespective of their alcohol status. The same relationship was observed between TE ratio and GGT ratio (r = 0.65, P < 0.0001). Evolution of TE was significantly correlated with the ratio of time of abstinence to observation time (r = -0.387, P = 0.016) and the evolution of liver enzymes. CONCLUSION TE significantly decreased with abstinence. Results of TE in alcoholic liver disease cannot be interpreted without taking into account alcohol consumption and liver enzymes.