Atherosclerotic cardiovascular disease and inflammatory bowel disease: epidemiology, pathogenesis and risk assessment

Inflammatory bowel diseases (IBD) are systemic inflammatory conditions increasingly recognized to confer excess risk of atherosclerotic cardiovascular disease (ASCVD), particularly in younger patients and during periods of active disease. We here synthesize evidence across epidemiology, mechanisms, risk stratification, and management at the IBD-ASCVD interface. Across population cohorts and meta-analyses, IBD associates with modest but consistent increases in ischemic heart disease, cerebrovascular events, and peripheral arterial disease, with higher relative risks for mesenteric ischaemia and for premature events; risk escalates with inflammatory burden and flares, while traditional factors alone partially explain the association. Prolonged corticosteroid exposure correlates with adverse vascular outcomes, whereas effective control of intestinal inflammation, particularly with anti-TNF biologics, appears protective; the absolute cardiovascular risk with Janus kinase inhibitors seems largely determined by baseline risk profile and is low in appropriately selected patients. Proposed drivers include dysbiosis and microbially derived metabolites (e.g., trimethylamine-N-oxide, imidazole propionate), intestinal barrier failure with low-grade endotoxemia and Toll-like receptor-4 activation, neutrophil- and platelet-mediated thromboinflammation, and inflammasome pathways that accelerate atherothrombosis. For risk stratification, non-invasive vascular measures (arterial stiffness, carotid intima-media thickness, coronary artery calcium) and general calculators (SCORE2/ASCVD) are informative, though underestimation in younger patients is possible; expert guidance emphasizes mitigation of inflammatory activity, smoking cessation, prudent steroid use, and lipid monitoring with small-molecule therapy. In conclusion, IBD confers clinically relevant ASCVD risk through immune-microbiome-barrier interactions superimposed on traditional factors. Routine cardiovascular assessment, aggressive control of intestinal inflammation, lifestyle optimization, and judicious therapy selection should be embedded in IBD care, while prospective studies refine prediction tools and test targeted preventive strategies across phenotypes and ages.