Residual Cholesterol and Residual Inflammation Risk Associated with In-Stent Restenosis

Background: Remnant cholesterol (remnant-C) and inflammation are considered risk factors for in-stent restenosis (ISR). We evaluate the combined impact of remnant-C and high-sensitivity C-reactive protein (hsCRP) on ISR. Methods A total of 1,503 patients were consecutively enrolled in this study. Baseline and follow-up remnant-C and hsCRP concentrations were obtained. The individual and combined effects of remnant-C and hsCRP on ISR were examined. Results The median (interquartile range) follow-up for all patients was 2.0 (0.9, 3.9) years, and 244 patients (16.2%) were diagnosed with ISR. Multivariate Cox analysis showed that the risk of ISR was higher in patients at the highest quartile of remnant-C (Q4 vs. Q1: adjusted hazard ratio HR 1.482, 95% confidence interval CI 1.013–2.168, p  = 0.042, p for trend 0.020) and hsCRP (Q4 vs. Q1: adjusted HR 1.620, 95% CI 1.121–2.339, p  = 0.010, p for trend 0.006). Moreover, the combination of high remnant-C and hsCRP produced a higher predictive value (adjusted HR: 1.904; 95% CI: 1.328–2.729; p  < 0.001) than low remnant-C and hsCRP. In a subgroup analysis, significant associations were observed between elevated remnant-C and hsCRP concentrations and the risk of ISR (HR 3.071, 95% CI 1.415–6.663, p  = 0.005) in patients with LDL-C levels ≤ 1.8 mmol/L. Conclusions Our results show that elevated remnant-C or hsCRP is associated with a high risk of ISR. The combined analysis of remnant-C and hsCRP could improve risk identification since high levels significantly increase the risk of ISR.