Lipid Immunometabolism in Autoimmune Rheumatic Diseases: Mechanistic Links Between Chronic Inflammation, Lipoprotein...

Patients with autoimmune rheumatic diseases, particularly rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), experience excess cardiovascular risk that is not fully captured by conventional lipid measurements. In active RA, lower cholesterol may coexist with higher vascular risk, a pattern known as the lipid paradox. We propose that systemic inflammation can uncouple lipid concentration from lipoprotein function and organize the evidence along five mechanistic axes. Inflammatory cytokines, mainly interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), IL-1β, IL-17/IL-23 and type I interferons, remodel lipoprotein metabolism. High-density lipoproteins (HDL) lose protective functions and may become pro-inflammatory. Apolipoprotein-B particles are oxidized or otherwise modified, linking lipid metabolism to autoimmunity. Macrophage cholesterol imbalance and cholesterol crystals activate inflammasome pathways in experimental atherosclerosis, while immune-cell metabolic rewiring may amplify cytokine output; these mechanisms are treated as extrapolated when direct rheumatic-disease evidence is limited. The pathways converge on endothelial dysfunction and thrombo-inflammation. RA and SLE are the mechanistic anchors, whereas psoriatic disease, axial spondyloarthritis, systemic sclerosis, vasculitides and antiphospholipid syndrome are weighted by evidence category. Standard lipid panels may therefore underestimate risk in selected contexts, especially during active inflammatory disease.