Abstract
BACKGROUND: The triglyceride-glucose (TyG) index is a reliable marker of insulin resistance, and the atherogenic index of plasma (AIP) reflects atherosclerosis. However, the relationship between these biomarkers-particularly AIP-and coronary microvascular dysfunction (CMD) in hypertensive patients has not been systematically studied. This study investigates the association between TyG, AIP, and CMD in hypertensive individuals. METHODS: We included 155 hypertensive patients with coronary anatomy confirmed by coronary angiography (CAG) or computed tomography angiography (CTA) within six months of SPECT imaging. CMD was diagnosed with a summed stress score (SSS) ≥4 and a summed difference score (SDS) ≥2. Patients were stratified into tertiles by TyG index and AIP. Logistic regression, adjusted for traditional cardiovascular risk factors, was used to explore the relationship with CMD. The predictive value of TyG and AIP was assessed using receiver operating characteristic (ROC) curves, and decision curve analysis (DCA) evaluated their clinical benefit. RESULTS: Logistic regression revealed that both TyG and AIP were independently associated with coronary artery disease (CAD) (P<0.05 for both). The area under the ROC curve (AUC) for TyG, AIP, and their combined predictive capacity for CMD was 0.744, 0.707, and 0.748, respectively (P<0.001 for all). The optimal cutoff values for TyG and AIP were 7.012 and 0.5175, respectively. Combining both biomarkers enhanced clinical decision-making and patient benefit. CONCLUSION: Higher levels of TyG and AIP are significantly associated with an increased risk of CMD in hypertensive patients. Both biomarkers exhibit strong predictive value, with AIP showing greater specificity and TyG higher sensitivity. Their combined use can improve clinical decision-making and patient outcomes.