Circulating Adipokines in Alcohol-Related Liver Disease and MetALD: A Systematic Review and Structured Narrative Synthesis.

Alcohol-related liver disease (ALD) and metabolic dysfunction and alcohol-related liver disease (MetALD) are increasingly recognised as biologically heterogeneous conditions, but circulating novel adipokines have not been systematically synthesised in this setting. We searched PubMed/MEDLINE, Embase, Web of Science, Scopus and Cochrane CENTRAL from inception to 31 December 2025 for studies measuring chemerin, visfatin/nicotinamide phosphoribosyltransferase (NAMPT), vaspin, omentin-1 or retinol-binding protein 4 (RBP-4) in adults with ALD or MetALD; data were synthesised narratively using Synthesis Without Meta-Analysis (SWiM). Grey literature and non-English databases were not searched, which may have led to incomplete retrieval of small single-centre studies. Five studies were included. Direct ALD evidence came mainly from three cross-sectional alcoholic cirrhosis cohorts, while one population cohort linked baseline RBP-4 to incident MetALD/ALD. RBP-4 showed a phase-dependent pattern, increasing before incident MetALD/ALD but decreasing in established cirrhosis with impaired synthetic function. Chemerin was reduced, omentin-1 was markedly elevated, vaspin was nonspecific and historical visfatin/NAMPT assays were difficult to interpret. Current evidence supports a hypothesis-generating three-axis framework: hepatic source failure, impaired hepatic clearance/portal-systemic shunting and alcohol-driven adipose-liver inflammation. The available evidence chiefly reflects chronic alcohol-related cirrhosis together with limited incident MetALD/ALD risk data, rather than the full ALD/MetALD spectrum. Prospective MetALD-stratified cohorts with isoform-specific assays and objective alcohol biomarkers are required.