Atherogenic Index of Plasma as a Risk Stratification Tool in Chronic Coronary Syndrome Patients Post‐PCI: A Retrospective Cohort Study

Background The atherogenic index of plasma (AIP) is a reliable indicator of lipid complexity. This study aimed to examine the link between AIP and the risk of percutaneous coronary intervention (PCI)–related adverse cardiovascular events in patients with chronic coronary syndromes (CCS). Methods This retrospective cohort study analyzed 2274 CCS patients stratified by AIP tertiles. The main composite endpoint was identified as either repeated revascularization or in‐stent restenosis. The study utilized Kaplan–Meier survival estimates and multivariable Cox proportional hazards models for statistical analysis of risk associations. Restricted cubic splines were used to model dose–response patterns, and receiver operating characteristic analysis determined the optimal prognostic threshold. Results Over a median surveillance period of 60.45 months, the primary endpoint was recorded in 1054 (46.4%) participants. A notable trend indicated that adverse event incidence rose alongside elevated AIP levels ( p = 0.001). After adjusting for potential confounders, AIP was identified as an independent predictor of the composite outcome (adjusted HR 1.087, 95% CI 1.023–1.154, p = 0.007). Patients in the highest AIP tertile had an 18.10% increased risk relative to those in the lowest tertile (adjusted HR: 1.181; 95% CI: 1.018–1.371; p = 0.028). A linear dose–response relationship was observed ( p nonlinear = 0.874), identifying an optimal cutoff value of 0.147. A significant interaction was observed between AIP and prior PCI history ( p = 0.045), with a pronounced association in patients without a history of PCI. Conclusions Higher AIP levels were independently associated with an increased risk of PCI‐related adverse cardiovascular events in patients with CCS, with a more pronounced association observed in those without prior PCI history. With a cutoff of 0.147, AIP may serve as an easily obtainable and complementary marker for risk stratification. Trial Registration This trial is registered with ChiCTR1800017128.