Association between the C-reactive protein-triglyceride-glucose index and the presence and prognosis of coronary microvascular dysfunction in patients with chronic coronary syndrome

Background Metabolic disturbances in lipid and glucose metabolism underlie coronary microvascular dysfunction (CMD) in chronic coronary syndromes (CCS), yet a practical biomarker integrating this metabolic risk is lacking. Methods In this single-center retrospective cohort, 421 CCS patients undergoing coronary angiography were included. CMD was defined by caIMR ≥ 25 U. C-reactive protein-triglyceride-glucose index (CTI), triglyceride-glucose index (TyG), and C-reactive protein (CRP) were measured. Associations with CTI and major adverse cardiovascular events (MACE) in CMD patients were analyzed using Cox regression, mediation, and ROC analyses. Results CTI was independently associated with CMD after full adjustment (Q4 vs. Q1: OR: 2.28, 95% CI: 1.16–4.49, p = 0.017), outperforming TyG and CRP. Over a median 35-month follow-up, higher CTI predicted increased MACE risk (fully adjusted HR for Q4: 2.62, 95% CI: 1.25–5.51, p = 0.011), especially in CMD patients (fully adjusted HR: 2.84, 95% CI: 1.06–7.62, p = 0.039). CTI demonstrated a superior predictive accuracy for CMD-related MACE compared with TyG (DeLong test p = 0.020). Conclusion CTI is a robust and independent predictor of both CMD and MACE in patients with CCS, supporting its use for early risk stratification and personalized management in patients with suspected or confirmed microvascular dysfunction.