Effect of lifetime alcohol consumption on the histological severity of non-alcoholic fatty liver disease

Abstract

Background & aims: Non-alcoholic fatty liver disease (NAFLD) is defined based on recent alcohol consumption; however, remote or lifetime alcohol consumption is not taken into account. It is not known whether lifetime alcohol consumption contributes to the severity of disease in patients with NAFLD. To determine the effect of lifetime alcohol consumption on the histological severity in patients with NAFLD.

Patients & methods: Adults >18 years of age with presumed NAFLD and alcohol consumption <40 g/week were enrolled. Lifetime alcohol consumption was determined using a questionnaire. Patients with a history of long-term alcohol abuse or dependence were excluded. A liver biopsy was reviewed by a single pathologist in a blinded fashion. Demographic, clinical and histological findings were compared in those who had regular alcohol consumption and those who did not.

Results: A total of 77 patients had fatty liver on biopsy. Fifty-two patients had a history of regular alcohol consumption. The median lifetime cumulative alcohol intake was 24 gram-years. On multivariable analysis, increasing age (OR 1.07, 95% CI 1.01-1.14) was associated with severe liver disease, whereas alcohol consumption of ≥24 gram-years was associated with less severe disease (OR 0.26, 95% CI 0.07-0.97, P = 0.04). Patients who continued to consume alcohol or had been abstinent for ≤1 year had less severe disease.

Conclusion: Some degree of regular alcohol consumption over the course of a lifetime compared to minimal intake appears to have a protective effect on the histological severity of liver disease among patients with strictly defined NAFLD.

Keywords: lifetime alcohol; non-alcoholic fatty liver disease; non-alcoholic steatohepatitis.