Alcohol Consumption and Its Effect on Liver Function Test—A Systematic Review and Meta-analysis

Abstract

Around 2.3 billion people globally consume alcohol, with Europe leading at 9.8 litres per capita. This high level of alcohol consumption significantly contributes to liver diseases, including alcoholic hepatitis, cirrhosis, and liver cancer. This review explores alcohol consumption's impact on liver function, focusing on alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) levels to understand liver health, disease progression, and influencing factors. The study used multiple databases and manual searches, with eligibility criteria including original research articles from diverse demographics and regions. Two independent reviewers conducted the screening process, minimizing bias and enhancing reliability. The Joanna Briggs Institute's critical appraisal checklist assessed the quality and risk of bias in the studies. Meta-Mar v3.5.1 was used for data analysis, with descriptive statistical tests and a random-effects model to synthesize findings across studies. Subgroup analyses were conducted to explore regional variations. The meta-analysis, incorporating data from 27 datasets across 13 studies, demonstrated a significant overall risk of alcohol consumption impacting liver function tests (LFTs). The pooled relative risk (RR) was 1.33 (95% CI: 0.97–1.82), as determined using a random-effects model (z/t = 1.86, p = 0.007). Higgins' I² statistic was extremely high at 99.4% (95% CI: 99.4%–99.5%), with an H value of 13.23 (95% CI: 12.49–14.01), confirming substantial heterogeneity (Q = 4550.29, df = 26, p = 0). The findings revealed that alcohol consumption increases the relative risk of elevated liver enzyme levels: ALT had a RR of 1.2625 (95% CI: 0.8459–1.8842), AST had an RR of 1.1783 (95% CI: 0.4851–2.8621), and GGT had a RR of 1.7645 (95% CI: 0.8241–3.7782). The observed outcomes regarding the effects of alcohol consumption on ALT, AST, and GGT were not significantly influenced by publication bias, as confirmed by Egger's regression analysis with no significant publication bias (t = 0.06, df = 25, p = 0.9558). Alcohol consumption negatively impacts LFTs, leading to elevated levels of key enzymes like ALT, AST, and GGT. This risk is consistent across geographical areas, suggesting the need for consideration in assessing alcohol's impact on liver health.