Alcohol consumption and liver phenotype of individuals with alpha-1 antitrypsin deficiency.

BACKGROUND AND AIMS

Alpha-1 antitrypsin deficiency is an inherited disorder caused by alpha-1 antitrypsin (AAT) mutations. We analysed the association between alcohol intake and liver-related parameters in individuals with the heterozygous/homozygous PiZ AAT variant (PiMZ/Pi*ZZ genotype) found in the United Kingdom Biobank and the European Alpha1 liver consortium.

METHODS

Reported alcohol consumption was evaluated in two cohorts: (i) the community-based United Kingdom Biobank (17 145 PiMZ, 141 PiZZ subjects, and 425 002 non-carriers [PiMM]); and (ii) the European Alpha1 liver consortium (561 PiZZ individuals). Cohort (ii) included measurements of carbohydrate-deficient transferrin (CDT).

RESULTS

In both cohorts, no/low alcohol intake was reported by >80% of individuals, while harmful consumption was rare (~1%). Among PiMM and PiMZ individuals from cohort (i), moderate alcohol consumption resulted in a <30% increased rate of elevated transaminases and ~50% increase in elevated gamma-glutamyl transferase values, while harmful alcohol intake led to an at least twofold increase in the abnormal levels. In PiZZ individuals from both cohorts, moderate alcohol consumption had no marked impact on serum transaminase levels. Among PiZZ subjects from cohort (ii) who reported no/low alcohol consumption, those with increased CDT levels more often had signs of advanced liver disease.

CONCLUSIONS

PiMZ/PiZZ genotype does not seem to markedly aggravate the hepatic toxicity of moderate alcohol consumption. CDT values might be helpful to detect alcohol consumption in those with advanced fibrosis. More data are needed to evaluate the impact of harmful alcohol consumption.