Serum apolipoprotein E levels predict residual cardiovascular risk in patients with chronic coronary syndrome undergoing first percutaneous coronary intervention and on-statin treatment.

Background And Aims: Little is known about the long-term impact of apolipoprotein E (apoE) on residual cardiovascular risk in patients with chronic coronary syndrome (CCS) receiving statin treatment.

Methods: A total of 1109 consecutive patients (mean age, 67 ± 10 years; 83% men) with CCS who underwent their first intervention between 2000 and 2016 were included in this study. All patients had achieved low-density lipoprotein cholesterol (LDL-C) <100 mg/dL on statin treatment and were divided into two groups based on median serum apoE values. We evaluated the incidence of major adverse cardiovascular events (MACEs), including cardiovascular death, non-fatal acute coronary syndrome, and target vessel revascularization.

Results: A total of 552 and 557 patients were categorized to the higher and lower apoE groups, respectively. There were significant relationships between apoE levels and total cholesterol levels, triglyceride levels, high-density lipoprotein cholesterol levels, and estimated remnant cholesterol, except for LDL-C levels. During the median follow-up period of 5.1 years, 195 patients (17.6%) developed MACEs. Kaplan-Meier analysis revealed that the cumulative incidence of MACEs in the higher apoE group was significantly higher than in the lower apoE group (29.5% vs.23.8% log-rank test, p = 0.019). Using multivariable Cox hazard analysis, serum apoE level (1-mg/dL increase) (hazard ratio 1.15; 95% confidence interval 1.03-1.29, p = 0.013) was the strongest independent predictor of MACEs.

Conclusions: Serum apoE level could be a strong predictor of residual cardiovascular risk in patients with CCS long-term, even if LDL-C levels are controlled with statin treatment.