Edited by: Stefan Zoltán Lutz, Bad Sebastiansweiler, Germany
Reviewed by: Norbert Stefan, University of Tübingen, Germany; Muath Alanbaei, Kuwait University, Kuwait
*Correspondence: Yi-Da Tang,
This article was submitted to Clinical Diabetes, a section of the journal Frontiers in Endocrinology
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
The triglyceride-glucose index (TyG index) is a valuable marker for predicting adverse cardiovascular events in diabetic patients. However, for nondiabetic patients, whether the TyG index is independently related to poor prognosis remains unclear. This cohort study assessed the association of the TyG index with future cardiovascular risk in nondiabetic subjects who received percutaneous coronary intervention (PCI).
We consecutively enrolled 5,489 nondiabetic patients who underwent PCI. All experimental subjects were divided into three groups based on their TyG index, which was determined by the equation ln (fasting triglyceride (mg/dl) × fasting blood glucose (mg/dl)/2). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), including all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, and target vessel revascularization (TVR).
A total of 386 MACCE were documented during a median 29-month follow-up. The Kaplan–Meier survival results indicated that among the three groups, there was no obvious difference in any endpoints. Further Cox regression analyses suggested that the TyG index was not independently related to adverse cardiovascular outcomes for nondiabetic patients who underwent PCI (HR: 0.77, 95% CI 0.56–1.16,
The TyG index is not an effective predictive factor for adverse cardiovascular prognosis in nondiabetic patients who underwent PCI. However, in subjects with LDL-C lower than 1.8mmol/L, it may predict future cardiovascular risk.
Cardiovascular and cerebrovascular diseases, particularly coronary artery disease (CAD), are the main cause of death (
The direct measure of IR is the hyperinsulinemic euglycemic glucose clamp. However, as a result of its complexity and invasiveness, it is rarely applied in clinical work. Homeostasis model assessment of IR (HOMA-IR) is commonly used clinically to assess IR, and some recent research has indicated that the TyG index is also a credible indicator of IR (
This research is a prospective observational cohort study that conformed to the Declaration of Helsinki and was authorized by the Fuwai Hospital’s Ethics Review Committee. All participants signed informed consent before PCI.
We consecutively enrolled 10,724 patients with CAD who had received PCI in Fuwai Hospital, Chinese National Center for Cardiovascular Diseases, from January 2013 to December 2013. According to the exclusion criteria, 3,257 patients were excluded for previous or new diagnosis DM or using (current or previous) oral hypoglycemic drugs, liraglutide or insulin; 1,610 patients were excluded for hemoglobin A1c (HbA1c) ≥6.5% or fasting blood glucose (FBG) ≥7.0 mmol/L; and 296 participants were excluded for not measuring HbA1c, FBG, or triglyceride (TG). Patients with very old age (age > 80 years), cardiogenic shock, severe renal insufficiency with endogenous creatinine clearance rate <30 ml/min/m2, extreme obesity [baseline body mass index (BMI) > 45 kg/m2], or lack of 2-year follow-up data were also excluded, and the detailed population screening process is shown in
Flowchart of the study population enrollment. PCI, percuntaneous coronary intervention; DM, diabetes mellitus; FBG, fasting blood glucose; HbA1c, Hemoglobin A1c; TG, triglycerides, TyG index, triglyceride-glucose index.
We collected baseline data consisting of age, sex, BMI, smoking history, types of CAD, previous history of hypertension, hyperlipemia, myocardial infarction (MI), hemorrhagic or ischemic stroke, PCI, and coronary artery bypass graft (CABG). Imaging and laboratory examinations, including left ventricle ejection fraction (LVEF), lipid parameters [total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and TG], glycemic parameters (HbA1c and FBG), high-sensitivity C-reactive protein (hs-CRP), and creatinine, were also measured by standardized methods, and laboratory tests were performed after an overnight fast. FBG, TG, TC, HDL-C, LDL-C, hs-CRP, and creatinine were assayed using a LABOSPECT 008 system (Hitachi, Tokyo, Japan), and the HbA1c value was determined by high-performance liquid chromatography (G8, TOSOH, Tokyo, Japan).
After coronary angiography and PCI were completed, characteristics of coronary stenosis [number of narrow coronary vessels, special types of CAD, and Synergy between PCI with TAXUS™ and cardiac surgery (SYNTAX) score] and the diameter and number of stents were evaluated by two coronary intervention experts who did not know the baseline data of the subjects before the evaluation (
We followed up with the patients at 1, 6, 12, and 24 months by telephone, letter, and clinic visits. All of the follow-up personnel were trained strictly and did not know the baseline data of patients. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), including all-cause mortality, nonfatal MI, nonfatal stroke, and target vessel revascularization (TVR). The secondary outcomes included MACE (a composite of cardiac death, nonfatal MI, and TVR), all-cause death, nonfatal MI, nonfatal stroke, and TVR. All-cause mortality was defined as any reason of death. We defined cardiac death as death from sudden death, heart failure, myocardial infarction, fatal arrhythmia, or any other fatal cardiovascular disease. Stroke and MI were defined as mentioned above. Target vessel revascularization was defined as ischemia-driven or clinically driven targeted vessel interventional therapy or surgery. We continued to follow the patients for up to 2 years to achieve the primary endpoint unless the patients died or were lost.
All statistical analyses and figures were treated by SPSS (version 23, Chicago, IL, USA) and R language version 4.0.3. If the continuous variables conformed to a normal distribution, they were described by the mean plus or minus the standard deviation, while other variables that were not in accordance with a normal distribution were shown as the median (interquartile range). Categorical variables are represented as quantities and percentages. We used ANOVA to compare the differences in measurement data among the three groups. For continuous variables that did not coincide with a normal distribution, the rank-sum test was applied to assess the differences between the three groups. We used the chi-square test to compare the categorical variables. Log-rank tests and K-M survival analyses were used to explore differences in long-term survival under different endpoint definitions. We performed collinearity analysis to explore variables that were significantly associated with the TyG index. Independent predictive factors for adverse cardiovascular events were determined by the Cox regression method. In the multivariate regression analysis, we included both traditional cardiovascular risk factors and variables that were intimate relative to prognosis in the univariate regression process. Variables that were significantly collinear with the TyG index were excluded. In addition, we further explored the effect of the TyG index on future cardiovascular events in different subgroups, including obesity, abnormal glucose metabolism, old age, and AMI. A two-sided
A total of 5,489 nondiabetic subjects were selected for the present study. Their average age was 57.20 ± 10.22 years old, 4,358 (79.4%) patients were male, overweight or obese patients accounted for 22.3%, 3,324 (60.6%) patients had a hypertension history, 3,482 (63.4%) patients were diagnosed with hyperlipemia, 3,221 (58.7%) subjects were current smokers, and 1,354 (24.7%) subjects had previously undergone PCI or CABG. All enrolled subjects were separated into three groups according to baseline TyG level [tertile 1 (
Baseline demographic and clinical data of the three groups.
Variable | Tertile 1 ( |
Tertile 2 ( |
Tertile 3 ( |
|
---|---|---|---|---|
TyG index | 8.24 ± 0.21 | 8.72 ± 0.11 | 9.26 ± 0.30 | <0.001 |
Age, years | 59.14 ± 10.20 | 57.07 ± 10.30 | 55.10 ± 9.82 | <0.001 |
Male, |
1,467 (80.2) | 1,449 (79.2) | 1,442 (78.8) | 0.341 |
BMI, kg/m2 | 24.84 ± 3.32 | 25.73 ± 3.02 | 26.39 ± 3.01 | <0.001 |
Hypertension, |
1,087 (59.4) | 1,100 (60.1) | 1,137 (62.2) | 0.084 |
Hyperlipemia, |
1,038 (56.7) | 1,166 (63.7) | 1,278 (70.4) | <0.001 |
Current smoker, |
1,038 (56.7) | 1,052 (57.5) | 1,131 (61.8) | 0.003 |
Previous stroke, |
171 (9.3) | 194 (10.6) | 125 (6.8) | 0.007 |
Previous MI, |
500 (27.3) | 544 (29.7) | 519 (28.4) | 0.489 |
Previous PCI, |
413 (22.6) | 362 (19.8) | 378 (20.9) | 0.147 |
Previous CABG, |
71 (3.9) | 68 (3.7) | 62 (3.4) | 0.446 |
Types of CAD | ||||
CCS, |
498 (27.2) | 564 (30.8) | 522 (28.5) | |
UA, |
1,418 (59.3) | 1,365 (54.0) | 1,337 (54.1) | 0.036 |
AMI, |
246 (13.4) | 277 (15.1) | 318 (17.4) | |
LM disease, |
102 (5.6) | 107 (5.8) | 91 (5.0) | 0.468 |
Multivessel disease, |
1,286 (70.3) | 1,309 (71.5) | 1,331 (72.7) | 0.098 |
Diffuse disease, |
1,030 (56.3) | 1,076 (58.8) | 1,129 (61.7) | 0.001 |
CTO disease, |
140 (7.7) | 144 (7.9) | 175 (9.6) | 0.034 |
ISR disease, |
124 (6.8) | 127 (6.9) | 113 (6.2) | 0.498 |
SYNTAX score | 9 (6, 16)* | 10 (6, 16)* | 10 (6, 16)* | 0.276 |
Diameter of stent | 2.75 (2.5, 3.0)* | 2.75 (2.5, 3.0)* | 2.75 (2.5, 3.0)* | 0.614 |
Numbers of stent | 2 (1, 2)* | 2 (1, 2)* | 2 (1, 2)* | 0.126 |
LVEF, (%) | 63.87 ± 6.74 | 63.09 ± 7.15 | 63.15 ± 7.21 | 0.005 |
FBG, mmol/L | 4.96 ± 0.53 | 5.16 ± 0.56 | 5.34 ± 0.61 | <0.001 |
HbA1c (%) | 5.85 ± 0.34 | 5.88 ± 0.33 | 5.91 ± 0.33 | <0.001 |
TG, mmol/L | 0.99 ± 0.20 | 1.51 ± 0.23 | 2.63 ± 1.23 | <0.001 |
TC, mmol/L | 3.78 ± 0.93 | 4.19 ± 1.00 | 4.67 ± 1.07 | <0.001 |
HDL-C, mmol/L | 1.13 ± 0.30 | 1.05 ± 0.28 | 0.97 ± 0.24 | <0.001 |
LDL-C, mmol/L | 2.24 ± 0.81 | 2.52 ± 0.89 | 2.76 ± 0.95 | <0.001 |
hs-CRP, mg/L | 1.11 (0.53, 2.62)* | 1.46 (0.76, 3.21)* | 1.75 (0.97, 3.71)* | <0.001 |
Creatinine, mmol/L | 73.94 ± 13.54 | 75.28 ± 14.44 | 75.89 ± 14.65 | 0.001 |
Data are represented as mean ± SD, medians with interquartile ranges* or n (%).
TyG index, triglyceride-glucose index; BMI, body mass index; MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass graft; CAD, coronary artery disease; CCS, chronic coronary syndrome; UA, unstable angina; LM, left main; CTO, chronic total occlusion; ISR, in-stent restenosis; SYNTAX, Synergy between PCI with TAXUS™ and cardiac surgery; LVEF, left ventricle ejection fraction; FBG, fasting blood glucose; HbA1c, Hemoglobin A1c; TG, triglycerides; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; hs-CRP, high-sensitivity C-reactive protein.
Collinearity analysis of baseline data with TyG index.
Unstandardized coefficients | Standardized coefficients |
|
Sig. | Collinearity statistics | |||
---|---|---|---|---|---|---|---|
|
Std. error | Beta | Tolerance | VIF | |||
(Constant) | 6.683 | 0.101 | 66.228 | 0.000 | |||
Age | −0.001 | 0.000 | −0.015 | −1.695 | 0.090 | 0.768 | 1.303 |
Sex | 0.055 | 0.013 | 0.045 | 4.328 | 0.000 | 0.569 | 1.758 |
BMI | 0.003 | 0.001 | 0.023 | 2.649 | 0.008 | 0.861 | 1.162 |
Hypertension | −0.003 | 0.008 | −0.003 | −0.342 | 0.733 | 0.904 | 1.106 |
Hyperlipemia | 0.023 | 0.008 | 0.023 | 2.844 | 0.005 | 0.937 | 1.067 |
Previous stroke | −0.013 | 0.013 | −0.008 | −0.980 | 0.327 | 0.952 | 1.050 |
Current smoker | 0.008 | 0.009 | 0.009 | 0.929 | 0.353 | 0.746 | 1.340 |
Previous MI | 0.024 | 0.009 | 0.023 | 2.844 | 0.005 | 0.937 | 1.067 |
Previous PCI | −0.014 | 0.012 | −0.011 | −1.100 | 0.271 | 0.664 | 1.507 |
Previous CABG | 0.015 | 0.029 | 0.005 | 0.530 | 0.596 | 0.871 | 1.148 |
AMI | −0.009 | 0.010 | −0.007 | −0.832 | 0.406 | 0.940 | 1.064 |
LM disease | 0.001 | 0.012 | 0.000 | 0.072 | 0.942 | 0.877 | 1.140 |
Multivessel disease | −0.001 | 0.010 | −0.001 | −0.146 | 0.884 | 0.895 | 1.118 |
Diffuse disease | 0.008 | 0.011 | 0.006 | 0.679 | 0.497 | 0.887 | 1.128 |
CTO disease | 0.007 | 0.012 | 0.005 | 0.598 | 0.550 | 0.908 | 1.101 |
ISR disease | 0.030 | 0.020 | 0.014 | 1.482 | 0.139 | 0.745 | 1.342 |
SYNTAX score | 0.000 | 0.001 | −0.003 | −0.352 | 0.725 | 0.747 | 1.338 |
Diameter of stent | −0.001 | 0.009 | −0.001 | −0.122 | 0.903 | 0.924 | 1.083 |
Number of stent | 0.001 | 0.006 | 0.001 | 0.113 | 0.910 | 0.918 | 1.089 |
LVEF | 0.001 | 0.001 | 0.010 | 1.128 | 0.259 | 0.814 | 1.229 |
FBG | 0.198 | 0.007 | 0.239 | 28.836 | 0.000 | 0.913 | 1.095 |
HbA1c | 0.026 | 0.012 | 0.018 | 2.193 | 0.028 | 0.899 | 1.113 |
TG | 0.482 | 0.009 | 0.956 | 54.579 | 0.000 | 0.204 | 4.893 |
TC | −0.184 | 0.024 | −0.413 | −7.714 | 0.000 | 0.022 | 45.680 |
HDL-C | 0.014 | 0.026 | 0.008 | 0.529 | 0.597 | 0.290 | 3.448 |
LDL-C | 0.232 | 0.025 | 0.444 | 9.399 | 0.000 | 0.028 | 35.563 |
hs-CRP | 0.000 | 0.001 | −0.003 | −0.351 | 0.725 | 0.860 | 1.113 |
Creatinine | 0.001 | 0.000 | 0.023 | 2.599 | 0.009 | 0.776 | 1.289 |
BMI, body mass index; MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass graft; AMI, acute myocardial infarction; LM, left main; CTO, chronic total occlusion; ISR, in-stent restenosis; SYNTAX, Synergy between PCI with TAXUS™ and cardiac surgery; LVEF, left ventricle ejection fraction; FBG, fasting blood glucose; HbA1c, hemoglobin A1c; TG, triglycerides; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; hs-CRP, high-sensitivity C-reactive protein.
A total of 5,489 patients completed 2 years of follow-up, and the mean value was 29.0 months. A total of 386 MACCE; 296 MACE; 55 all-cause deaths, 25 of which were cardiac deaths; 40 nonfatal MIs; 81 nonfatal strokes; and 248 TVRs were documented. The Kaplan–Meier survival analyses indicated that there was no statistical discrepancy among the three groups regarding all endpoints (
Kaplan-Meier analyses for different endpoints among the three groups:
Univariate and multivariate Cox regression analyses for predicting the occurrence of MACCE.
Variable | Univariate analysis | Multivariate analysis | ||||
---|---|---|---|---|---|---|
HR | 95% CI |
|
HR | 95% CI |
|
|
TyG index | 1.16 | 0.95–1.44 | 0.148 | 0.77 | 0.52–1.16 | 0.210 |
Age, years | 1.01 | 1.00–1.02 | 0.006 | 1.00 | 0.98–1.02 | 0.997 |
Male | 1.03 | 0.81–1.32 | 0.815 | 0.93 | 0.58–1.48 | 0.925 |
BMI, kg/m2 | 1.01 | 0.98–1.04 | 0.537 | |||
Hypertension | 1.08 | 0.88–1.33 | 0.462 | |||
Hyperlipemia | 1.20 | 0.97–1.49 | 0.088 | 1.24 | 0.85–1.80 | 0.262 |
Current smoker | 0.95 | 0.78–1.16 | 0.623 | |||
Previous stroke | 1.58 | 1.18–2.12 | 0.002 | 2.07 | 1.30–3.29 | 0.002 |
Previous MI | 1.21 | 0.98–1.50 | 0.081 | 0.89 | 0.60–1.34 | 0.588 |
Previous PCI | 1.46 | 1.17–1.82 | 0.001 | 1.31 | 0.79–2.18 | 0.291 |
Previous CABG | 1.48 | 0.94–2.32 | 0.087 | 0.66 | 0.16–2.82 | 0.575 |
AMI | 1.12 | 0.86–1.46 | 0.401 | |||
LM disease | 1.00 | 0.64–1.55 | 0.995 | |||
Multivessel disease | 1.44 | 1.13–1.84 | 0.003 | 1.50 | 0.90–2.50 | 0.122 |
CTO disease | 2.00 | 1.51–2.65 | <0.001 | 0.92 | 0.55–1.54 | 0.742 |
ISR disease | 1.68 | 1.21–2.32 | 0.002 | 1.30 | 0.60–2.81 | 0.503 |
SYNTAX score | 1.40 | 1.09–1.61 | 0.017 | 1.37 | 1.01–1.59 | 0.043 |
Diameter of stent | 0.97 | 0.87–1.08 | 0.585 | |||
Number of stents | 1.03 | 1.02–1.04 | <0.001 | 1.02 | 1.00–1.04 | 0.057 |
LVEF, (%) | 0.97 | 0.96–0.99 | <0.001 | 0.97 | 0.95–0.99 | 0.012 |
FBG, mmol/L | 1.24 | 1.05–1.46 | 0.012 | 1.11 | 0.82–1.52 | 0.498 |
HbA1c (%) | 1.51 | 1.10–2.06 | 0.010 | 1.62 | 0.91–2.89 | 0.102 |
TG, mmol/L | 1.08 | 0.98–1.19 | 0.103 | |||
TC, mmol/L | 1.03 | 0.94–1.13 | 0.533 | |||
HDL-C, mmol/L | 0.83 | 0.58–1.19 | 0.312 | |||
LDL-C, mmol/L | 1.03 | 0.92–1.14 | 0.649 | |||
hs-CRP, mg/L | 1.03 | 1.01–1.06 | 0.009 | 1.01 | 0.97–1.06 | 0.210 |
Creatinine, mmol/L | 1.00 | 1.00–1.01 | 0.346 |
TyG index, triglyceride-glucose index; BMI, body mass index; MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass graft; CAD, coronary artery disease; AMI, acute myocardial infarction; LM, left main; CTO, chronic total occlusion; ISR, in-stent restenosis; SYNTAX, Synergy between PCI with TAXUS™ and cardiac surgery; LVEF, left ventricle ejection fraction; FBG, fasting blood glucose; HbA1c, hemoglobin A1c; TG, triglycerides; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; hs-CRP, high-sensitivity C-reactive protein.
Univariate and multivariate Cox regression analyses for predicting the occurrence of MACE.
Variable | Univariate analysis | Multivariate analysis | ||||
---|---|---|---|---|---|---|
HR | 95% CI |
|
HR | 95% CI |
|
|
TyG index | 1.32 | 1.04–1.67 | 0.021 | 0.79 | 0.29–2.15 | 0.650 |
Age, years | 1.00 | 0.99–1.01 | 0.838 | 0.99 | 0.97–1.01 | 0.184 |
Male | 0.93 | 0.70–1.24 | 0.600 | 1.11 | 0.67–1.83 | 0.694 |
BMI, kg/m2 | 1.02 | 0.98–1.05 | 0.333 | |||
Hypertension | 1.01 | 0.80–1.27 | 0.939 | |||
Hyperlipemia | 1.17 | 0.91–1.48 | 0.217 | |||
Current smoker | 0.96 | 0.76–1.21 | 0.724 | |||
Previous stroke | 1.29 | 0.90–1.85 | 0.169 | |||
Previous MI | 1.12 | 0.87–1.43 | 0.375 | |||
Previous PCI | 1.56 | 1.21–2.00 | 0.001 | 1.65 | 0.97–2.80 | 0.063 |
Previous CABG | 1.54 | 0.93–2.55 | 0.093 | 0.63 | 0.15–2.70 | 0.529 |
AMI | 1.15 | 0.85–1.56 | 0.359 | |||
LM disease | 1.06 | 0.65–1.74 | 0.803 | |||
Multivessel disease | 1.61 | 1.21–2.14 | 0.001 | 1.55 | 0.87–2.76 | 0.134 |
CTO disease | 2.33 | 1.72–3.16 | <0.001 | 0.81 | 0.45–1.45 | 0.479 |
ISR disease | 1.81 | 1.26–2.60 | 0.001 | 1.43 | 0.66–3.10 | 0.370 |
SYNTAX score | 1.04 | 1.02–1.05 | <0.001 | 1.03 | 1.01–1.05 | 0.023 |
Diameter of stent | 0.56 | 0.35–0.89 | 0.015 | 0.58 | 0.35–0.94 | 0.028 |
Number of stents | 0.98 | 0.86–1.11 | 0.719 | |||
LVEF, (%) | 0.97 | 0.96–0.99 | <0.001 | 0.98 | 0.96–1.01 | 0.177 |
FBG, mmol/L | 1.17 | 0.97–1.41 | 0.105 | |||
HbA1c (%) | 1.66 | 1.15–2.38 | 0.006 | 1.41 | 0.76–2.62 | 0.276 |
TG, mmol/L | 1.14 | 1.04–1.26 | 0.005 | 0.98 | 0.57–1.69 | 0.953 |
TC, mmol/L | 1.05 | 0.94–1.16 | 0.377 | |||
HDL-C, mmol/L | 0.74 | 0.48–1.12 | 0.149 | |||
LDL-C, mmol/L | 1.03 | 0.91–1.16 | 0.670 | |||
hs-CRP, mg/L | 1.03 | 1.00–1.06 | 0.079 | 1.02 | 0.97–1.08 | 0.401 |
Creatinine, mmol/L | 1.00 | 0.99–1.01 | 0.821 |
TyG index, triglyceride-glucose index; BMI, body mass index; MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass graft; CAD, coronary artery disease; AMI, acute myocardial infarction; LM, left main; CTO, chronic total occlusion; ISR, in-stent restenosis; SYNTAX, Synergy between PCI with TAXUS™ and cardiac surgery; LVEF, left ventricle ejection fraction; FBG, fasting blood glucose; HbA1c, hemoglobin A1c; TG, triglycerides; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; hs-CRP, high-sensitivity C-reactive protein.
Subgroup analysis for the effect of the TyG index on the risk of the primary endpoint. The analysis was performed by adjusting for Model (age, gender, dyslipidemia, previous history of stroke, MI, PCI, and CABG, Multivessel disease, CTO disease, ISR disease, SYNTAX score, numbers of stent, LVEF, FBG, HbA1c and hs-CRP). BMI, body mass index; AMI, acute myocardial infarction; FBG, fasting blood glucose; HbA1c, glycosylated hemoglobin A1c; TG, triglyceride; LDL-C, low-density lipoprotein cholesterol; HR, hazard ratio; CI, confidence interval.
The present study explored the predictive value of the TyG index in adverse cardiovascular outcomes for nondiabetic subjects who underwent PCI, and the results included the following two findings: 1) the TyG index was not related to cardiovascular adverse events, including MACCE, MACE, all-cause death, cardiac mortality, nonfatal MI, nonfatal stroke, or TVR, independently after adjusting for other cardiovascular risk factors. 2) In the LDL-C lower than 1.8 mmol/L subgroup, this index may be an independent predictive factor for MACCE.
Insulin resistance refers to the dysfunction of insulin in facilitating glucose assimilation and utilization for various reasons, leading to excessive compensatory secretion of insulin to maintain the stability of blood glucose. IR can accelerate the progression of atherosclerosis in several ways, including hyperinsulinemia and hyperglycemia, dyslipidemia (hypertriglyceridemia, low HDL-C level, and the emergence of small dense LDL), hypertension, and endothelial dysfunction (
Many studies have shown that this indicator is associated with exacerbation and poor prognosis in CAD patients, especially those with concurrent diabetes mellitus. Wang et al. consecutively enrolled 2,531 diabetic patients who were diagnosed with ACS with a median follow-up of 36 months. They found that this index was closely related to the primary outcome, including all-cause death, nonfatal myocardial infarction, and nonfatal stroke, which can be used as a predictor (
The results of this study are different from those of Zhao et al. for the following possible reasons. First, we selected different subjects. All patients included in the study of Zhao et al. were ACS patients, while the present study enrolled some patients diagnosed with CCS. ACS patients are prone to stress hyperglycemia and are associated with poor prognosis, which may obscure the true effect of the TyG index on prognosis (
This is the first study focused on the role of the TyG index in nondiabetic subjects who underwent PCI. In this research, the follow-up period was relatively long, and the corresponding sample size was sufficiently large. Fuwai Hospital is the medical center with the largest number of coronary interventional therapies in China, and the level of interventional therapy is relatively high, so the samples are representative to some extent. Of course, this study also has some limitations. For example, it was a single-center study, and the enrolled patients were all Chinese. In addition, the study did not record abdominal circumference, hip circumference, or NAFLD, which are important and independent risk factors for CVD (
The TyG index was not independently relevant to adverse cardiovascular events in nondiabetic patients who underwent PCI. However, in subjects with LDL-C lower than 1.8 mmol/L, it may predict adverse cardiovascular prognosis. More large-scale prospective research should be carried out in the future to explore the predictive effect of this index in nondiabetic patients who receive PCI, especially patients with well-controlled LDL-C.
The datasets presented in this article are not readily available because the raw data are stored in the hospital’s computer system and are restricted from copying. Requests to access the datasets should be directed to Y-DT (
The studies involving human participants were reviewed and approved by Fuwai Hospital’s Ethics Review Committee. The patients/participants provided their written informed consent to participate in this study.
JY, CS, and Y-DT participated in the study design. YZ, CL, QZ, JG, and XM participated in data collection. JY, KZ, and WW performed the statistical analysis. JY drafted the article. All authors contributed to the article and approved the submitted version.
This work was supported by National Key R&D Program of China (2020YFC2004700) and the Beijing Nova Program (Z201100006820002) from Beijing Municipal Science & Technology Commission.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
We thank all the investigators and subjects who participated in this project.