Background and aim: Moderate alcohol consumption has been associated with a lower risk of disease severity in non-alcoholic fatty liver disease (NAFLD). It is unclear if this reflects current or lifetime drinking, or can be attributed to confounders such as diet and exercise. We evaluated the impact of lifetime alcohol consumption on fibrosis severity in NAFLD.

Methods: We prospectively enrolled 120 subjects with biopsy-proven NAFLD and through detailed questionnaires examined lifetime alcohol consumption, diet and physical activity. Main outcome measures were odds ratios (OR) for fibrosis stage, calculated through ordinal regression after adjustment for body mass index, diabetes mellitus type 2, smoking and age at biopsy. A biomarker for recent alcohol consumption, phosphatidyl ethanol (PEth) was sampled.

Results: An increase in median weekly alcohol consumption to a maximum of 13 drinks per week was associated with lower fibrosis stage (adjusted OR for each incremental unit, 0.86; 95% CI, 0.76–0.97; p = .017). The lowest risk for fibrosis was found with the lowes`t odds seen in the top quartile of alcohol consumption (aOR 0.23; 95% CI 0.08–0.66; p = .006). Adding soft drink and coffee consumptions, and physical activity to the model did not change the estimates. Subjects with PEth ≥0.3 μmol/L had higher ORs for a higher fibrosis stage (aOR 2.77; 95% CI 1.01–7.59; p = .047).

Conclusion: Lifetime alcohol consumption with up to 13 units per week is associated with lower fibrosis stage in NAFLD. Elevated PEth is associated with higher stages of fibrosis.