Metabolically associated fatty liver disease (MAFLD) is a prevalent liver disorder strongly linked to metabolic dysfunction. Rheumatoid arthritis (RA), a chronic autoimmune disease, is increasingly recognized for its association with metabolic disturbances and hepatic involvement.
Objective: This review explores the pathophysiological interactions between MAFLD and RA, emphasizing shared inflammatory and metabolic mechanisms.
Methods: A narrative literature review was conducted using recent clinical and experimental studies to elucidate common pathways, particularly the role of fibroblast growth factor 21 (FGF21).
Results: Both diseases share key mechanisms including insulin resistance, chronic inflammation, and cytokine-mediated tissue damage. FGF21 emerges as a potential integrative biomarker and therapeutic target due to its dual involvement in metabolic regulation and inflammation.
Conclusion: Recognizing and addressing the bidirectional relationship between MAFLD and RA is essential for effective disease management. Monitoring FGF21 levels may improve risk stratification and guide individualized therapy.

Metabolically associated fatty liver disease (MAFLD), rheumatoid arthritis (RA), chronic inflammation, fibroblast growth factor 21 (FGF21), insulin resistance, steatohepatitis, diagnosis, liver fibrosis, anti-inflammatory therapy.

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