Joint and interaction association of red cell distribution width and uric acid with major adverse cardiovascular events in patients undergoing PCI

Abstract Elevated red cell distribution width (RDW) and hyperuricemia (HUA) have been individually associated with poor prognosis in coronary artery disease (CAD), yet their joint and interactive effects in patients undergoing percutaneous coronary intervention (PCI) remain unclear. In this retrospective study of 5,926 patients with CAD who underwent PCI, patients were classified into four groups according to RDW and UA levels, and major adverse cardiovascular events (MACE) were the outcome. Cox regression, interaction, and mediation analyses were performed. During a median follow-up of 729 days, 631 patients (11.9%) experienced MACE. Versus the low-RDW/non-HUA reference, the high-RDW/HUA (HR 1.621, P < 0.001) and high-RDW/non-HUA (HR 1.233, P = 0.039) groups had significantly higher MACE risk, with no significant increase in the low-RDW/HUA group (HR 1.082, P = 0.559). No significant multiplicative or additive interaction was observed (RERI 0.306; multiplicative HR 1.215). RDW partially mediated the association between UA and MACE, with a mediation proportion of 15.4%. Combined UA and RDW improved risk discrimination modestly over either marker alone (AUC: 0.572 vs. 0.554 vs. 0.541). Elevated RDW and HUA exert joint effects on MACE, with RDW partially mediating UA-related risk. Combined assessment may refine risk stratification in PCI patients.