Biomarkers of liver status in heavy drinkers, moderate drinkers and abstainers

Although a wide variety of biomarkers reflecting liver status are known to be influenced by excessive ethanol consumption, the dose-response relationships between ethanol intake and marker changes have remained less understood.

Serum gamma-glutamyltransferase (GGT), aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities, and ferritin and albumin protein concentrations were compared in a large population of heavy drinkers (105 men, 28 women), moderate drinkers (781 men, 723 women) and abstainers (252 men, 433 women), who were devoid of apparent liver disease.

In heavy drinkers, serum GGT, AST, ALT, ferritin and albumin were all significantly higher than in moderate drinkers or abstainers (P < 0.001 for all comparisons). The highest incidences of elevated values were found for GGT (62%) followed by AST (53%), ALT (39%), ferritin (34%) and albumin (20%). Serum GGT (P < 0.001), ALT (P < 0.01) and ferritin (P < 0.05) in moderate drinkers were also higher than the levels observed in abstainers. When the study population was further divided into subgroups according to gender, significant differences between moderate drinkers and abstainers in GGT and ALT were noted in men whereas not in women.

The data demonstrate that biomarkers of alcohol abuse and liver function may respond to even rather low levels of ethanol intake in a gender-dependent manner, which should be implicated in studies on the early-phase interactions of ethanol and the liver and in the definition of normal ranges for such biomarkers.