Nomograms Based on Non-High-Density Lipoprotein to Predict Outcomes in Patients with Prior Coronary Artery Bypass Grafting with Acute Coronary Syndrome: A Single-Center Retrospective Study

Abstract

Introduction

Non-high-density-lipoprotein cholesterol (non-HDL-C) is a secondary therapeutic target in cardiovascular diseases and is used for residual risk assessment in patients with coronary artery syndrome (ACS). This study was designed to determine the association between non-HDL-C in patients with prior coronary artery bypass graft (CABG) with ACS and clinical outcomes.

Methods

We retrospectively analyzed 468 patients with prior CABG with ACS and categorized them into two groups based on the median non-HDL-C level. The primary endpoints were major adverse cardiovascular events (MACEs), including cardiovascular death and recurrent myocardial infarction. Kaplan–Meier curves, Cox proportional-hazard regressions, and restricted cubic splines were used to determine the association between non-HDL-C and MACEs. The discrimination and reclassification of the nomogram based on non-HDL-C were assessed using time-dependent receiver operating characteristic (ROC) curves and net reclassification improvement (NRI).

Results

During the average follow-up time of 744.5 days, non-HDL-C was independently associated with the occurrence of MACEs (hazard ratio [HR] = 5.01, 95% confidence interval [CI] = 1.65–15.24; p = 0.005) after adjusting for other lipid parameters. The spline curves indicated a linear relationship between non-HDL-C and MACEs (p-nonlinear: 0.863). The time-dependent areas under the ROC curves of prior-CABG-ACS nomograms containing non-HDL regarding MACEs in two consecutive years were 91.7 (95% CI: 85.5–97.9) and 91.5 (95% CI: 87.3–95.7), respectively. The NRI analysis indicated that the prior-CABG-ACS model improved the reclassification ability for 1- and 2-year MACEs (22.4% and 7%, p < 0.05, respectively).

Discussion

Non-HDL is independently associated with the risk of MACEs in patients with prior CABG with ACS. The prior-CABG-ACS nomogram based on non-HDL-C and five convenient variables generates valid and stable predictions of MACE occurrence.

Keywords:

• non-HDL cholesterol
• major adverse cardiovascular events
• prior coronary artery bypass grafting
• GRACE score

Abbreviations

ACS, acute coronary syndrome; MACE, major adverse cardiovascular events; CAD, coronary artery disease; PCI, percutaneous coronary intervention; GRACE, Global Registry of Acute Coronary Events; MI, myocardial infarction; CABG, coronary artery bypass grafting; TC, total cholesterol; LDL-C, low-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol; TG, triglyceride; CCr, creatinine clearance rate; ESR, erythrocyte sedimentation rate; hs-CRP, high-sensitivity C-reactive protein; CTNI, cardiac troponin I; CKMB, creatine kinase–myocardial band; BMI, body mass index; LVEF, left ventricular ejection fraction; ROC, receiver operating characteristic; AUC, area under ROC; NRI, net reclassification improvement.

Data Sharing Statement

The datasets generated and analyzed are not publicly available because of the policies of the Beijing Chaoyang Hospital regarding individual confidentiality; however, they are available from the corresponding author upon reasonable request.

Ethics and Consent to Participate

This study was approved by the Ethics Committee of the Beijing Chaoyang Hospital with Capital Medical University. All procedures in this study were performed according to the ethical standards of the Beijing Chaoyang Hospital with Capital Medical University Research Committee and the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Acknowledgments

Chuang Li and Kuizheng He are co-first authors for this study. Xiaorong Xu and Weiming Li are co-correspondence authors for this study.

Disclosure

All authors declare no conflicts of interest in this work.

Additional information

Funding

There is no funding to report.