Predictive value of serum TBA for 2-year MACEs in ACS patients undergoing PCI: a prospective cohort study

Abstract

Bile acids play important roles in lipid metabolism and glucose homeostasis. Limited research exist on the association between serum total bile acid (TBA) levels and major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS), particularly those with comorbid type 2 diabetes mellitus (T2DM). This study was conducted to examine the relationship between baseline serum TBA level and T2DM status in patients with ACS after percutaneous coronary intervention (PCI) and to identify the predictive value of TBA levels for a 2-year risk of MACEs. 425 ACS patients underwent PCI were recruited and divided into three groups based on baseline serum TBA concentration. An analysis of the association between the T2DM status and baseline serum TBA levels was conducted using univariate linear regression and multivariate linear regression. The predictive relevance of serum TBA levels was evaluated using the receiver operating characteristic (ROC) curve and Cox regression. Kaplan-Meier curves were employed to analyze the differences among groups in predicting MACEs over a 2-year follow-up period. Baseline serum TBA levels were higher in ACS patients who were diagnosed with T2DM (the median 3.6 µmol/L) than those without T2DM (the median 3.0 µmol/L). T2DM status in ACS patients was positively correlated with baseline serum TBA concentrations (β: 1.7, 95% confidence interval [CI] 0.3-3.0), particularly in the male (β: 2.0, 95% CI 0.3-3.6) and 50-69-year-old (β: 2.5, 95% CI 0.6-4.4) populations. The areas under the ROC curve of baseline serum TBA levels predicted MACEs in ACS and ACS-T2DM patients following PCI were 0.649 (95% CI 0.595-0.703) and 0.783 (95% CI 0.685-0.881), respectively. Furthermore, Cox regression analysis showed that baseline serum TBA level was associated with the occurrence of MACEs in patients with ACS after PCI over a 2-year follow-up period, especially in those diagnosed with T2DM, whose baseline TBA concentration was lower than 10.0 µmol/L. ACS Patients with T2DM had higher serum TBA levels. TBA level at baseline was an independent predictor of MACEs in ACS patients who underwent PCI, especially with comorbid T2DM.

Figure 1

The ROC curves of TBA as a marker to predict MACEs in the whole patients (A), patients with T2DM (B), and without T2DM (C), following PCI (all P < 0.05). ROC Receiver operating characteristic; TBA Total bile acids; MACEs Major adverse cardiovascular events; DM Diabetes mellitus; PCI Percutaneous coronary intervention; AUC Area under ROC curves.

Figure 2

Kaplan–Meier survival curves. The prediction of MACEs over a 2-year follow-up in low-level (≤ 3.1 µmol/L), medium-level (> 3.1 µmol/L, ≤ 10 µmol/L) and high-level (> 10 µmol/L) TBA groups in ACS patients after PCI.