The ApoB/ApoA-I ratio and the risk of in-stent restenosis following drug-eluting stent implantation in patients with coronary heart disease: a retrospective cohort study.

OBJECTIVE: The Apolipoprotein B/Apolipoprotein A-I (ApoB/ApoA-I) ratio has been strongly associated with the risk of cardiovascular disease. However, its association with in-stent restenosis (ISR) after drug-eluting stent (DES) implantation in patients with coronary heart disease (CHD) remains unclear. METHODS: This retrospective study enrolled CHD patients who underwent follow-up coronary angiography 6-24 months after successful DES-based percutaneous coronary intervention (PCI). The ApoB/ApoA-I ratio was calculated, and participants were grouped by quartiles of the ratio. Multivariable logistic regression and restricted spline cubic (RCS) models assessed the association between the ApoB/ApoA-I ratio and ISR risk. Subgroup and sensitivity analyses were also conducted. RESULTS: A total of 1,004 CHD patients (mean age 67.32 ± 10.63 years, 63.65% male) were included. 176 (17.5%) patients developed ISR over a median 12-month follow-up. The prevalence of ISR rose stepwise with increasing quartiles of the ApoB/ApoA-I ratio (5.6% vs. 11.2% vs. 20.3% vs. 32.6%, P < 0.001), and the ratio was higher in the ISR group than in the non-ISR group (0.86 ± 0.28 vs. 0.67 ± 0.21, P < 0.001). After full adjustment for confounders, the ApoB/ApoA-I ratio remained positively associated with ISR risk [per 1-SD increase: odds ratios (OR) = 2.39, 95% CI: 1.81-3.15, P < 0.001]. Using the first quartile as reference, the OR for the third and fourth quartiles were 3.48 (95% CI: 1.67-7.22, P = 0.001) and 6.09 (95% CI: 2.66-13.93, P < 0.001), respectively. Sensitivity analyses supported these findings. RCS analysis indicated a linear dose-response relationship between the ApoB/ApoA-I ratio and ISR risk (P for overall <0.001, P for nonlinear = 0.332). Subgroup analyses confirmed the consistent association across all subgroups (all P for interaction >0.05). Moreover, adding ApoB/ApoA-I ratio to the predictive model for ISR could contribute to an increase in C-statistics (0.732 vs. 0.768, P = 0.001), categorical net reclassifcation improvement (0.128, P = 0.001), and integrated discrimination improvement (0.053, P < 0.001). CONCLUSIONS: An elevated ApoB/ApoA-I ratio was significantly associated with an increased risk for ISR after DES-based PCI in CHD patients. Our findings suggested that the ApoB/ApoA-I ratio might serve as a useful predictor for ISR risk in this population.