Impact of insulin resistance on post-procedural myocardial injury and clinical outcomes in patients who underwent elective coronary interventions with drug-eluting stents

The association between triglyceride glucose-body mass index and all-cause and cardiovascular mortality in diabetes patients: a retrospective study from NHANES database

The triglyceride glucose body mass index (TyG-BMI) is a potential indicator for insulin resistance, but its association with mortality in diabetic patients is unclear. This study investigates the relationship between TyG-BMI and all-cause and cardiovascular mortality in diabetics. The study included 3109 diabetic patients from the National Health and Nutrition Examination Survey (2001-2018). Mortality data were obtained from National Death Index records until 31 December 2019. Multivariate Cox models analyzed the association between TyG-BMI and mortality. Non-linear correlations were assessed using restricted cubic splines, and a two-piecewise Cox model evaluated the relationship on both sides of the inflection point. Over a median 7.25-year follow-up, 795 total and 238 cardiovascular deaths occurred. A U-shaped link was found between initial TyG-BMI and mortality in diabetic patients. Low TyG-BMI (< 279.67 for all-cause, < 270.19 for CVD) reduced death risks (all-cause: HR 0.77, 95% CI 0.69-0.86; CVD: HR 0.64, 95% CI 0.48-0.86). High TyG-BMI (> 279.67 for all-cause, > 270.19 for CVD) increased these risks (all-cause: HR 1.26, 95% CI 1.10-1.44; CVD: HR 1.33, 95% CI 1.06-1.68). In the NHANES study population, a U-shaped association was observed between the baseline TyG-BMI index and all-cause mortality or CVD in diabetic patients.

Triglyceride-glucose index is associated with myocardial ischemia and poor prognosis in patients with ischemia and no obstructive coronary artery disease

BACKGROUND

Ischemia and no obstructive coronary artery disease (INOCA) is increasingly recognized and associated with poor outcomes. The triglyceride-glucose (TyG) index is a reliable alternative measure of insulin resistance significantly linked to cardiovascular disease and adverse prognosis. We investigated the association between the TyG index and myocardial ischemia and the prognosis in INOCA patients.

METHODS

INOCA patients who underwent both coronary angiography and myocardial perfusion imaging (MPI) were included consecutively. All participants were divided into three groups according to TyG tertiles (T1, T2, and T3). Abnormal MPI for myocardial ischemia in individual coronary territories was defined as summed stress score (SSS) ≥ 4 and summed difference score (SDS) ≥ 2. SSS refers to the sum of all defects in the stress images, and SDS is the difference of the sum of all defects between the rest images and stress images. All patients were followed up for major adverse cardiac events (MACE).

RESULTS

Among 332 INOCA patients, 113 (34.0%) had abnormal MPI. Patients with higher TyG index had a higher rate of abnormal MPI (25.5% vs. 32.4% vs. 44.1%; p = 0.012). Multivariate logistic analysis showed that a high TyG index was significantly correlated with abnormal MPI in INOCA patients (OR, 1.901; 95% CI, 1.045-3.458; P = 0.035). During the median 35 months of follow-up, 83 (25%) MACE were recorded, and a higher incidence of MACE was observed in the T3 group (T3 vs. T2 vs. T1: 36.9% vs. 21.6% vs. 16.4%, respectively; p = 0.001). In multivariate Cox regression analysis, the T3 group was significantly associated with the risk of MACE compared to the T1 group (HR, 2.338; 95% CI 1.253-4.364, P = 0.008).

CONCLUSION

This study indicates for the first time that the TyG index is significantly associated with myocardial ischemia and poor prognosis among INOCA patients.

Predictive value of triglyceride/glucose index for cardiac outcomes in non-diabetic renal transplant recipients

OBJECTIVES

Insulin resistance (IR) is associated with an increased risk of adverse cardiovascular outcomes. The triglyceride-glucose index (TyG index) is a reliable marker of IR. No study has examined the impact of the TyG index on major adverse cardiac and cerebrovascular events (MACCEs) in RTRs. Therefore, this study aimed to investigate the predictive value of the TyG index for MACCEs in RTRs.

MATERIALS AND METHODS

Non-diabetic patients undergoing renal transplantation were retrospectively enrolled. The patients were divided into two groups according to MACCE development. The cut-off value of the TyG index for MACCE was conducted.

RESULTS

The mean age of 522 patients was 41 (31-51) years, and 349 (66.9%) were male. During the 5.4-year follow-up, 84 (16%) MACCE were recorded. TyG index was significantly higher in the group that developed MACCE (p < 0,001). Cox regression analysis revealed that TyG index [HR: 3.297 (1.228-8.855), p = 0.018], left ventricle ejection fraction [HR: 0.934 (0.900-0.968), p < 0.001], cadaveric transplantation [HR: 8.886 (4.764-16.576), p < 0.001], graft survey [HR: 0.608 (0.542-0.682), p < 0.001)], and smoking [HR: 1.965 (1.117-3.456), p = 0.019] were independent predictors of MACCEs in nondiabetic RTRs.

CONCLUSION

TyG index is an independent predictor of MACCEs in non-diabetic RTRs. The widespread use of the TyG index may positively affect long-term treatment costs and survival.

Interaction between triglyceride-glucose index and thyroid hormones on coronary artery disease risk in patient with euthyroid

Background

Triglyceride-glucose (TyG) index is an effective indicator in indentifying in pre-diabetes, diabetes, and coronary artery disease (CAD). However, the value of TyG index combined with thyroid hormones (THs) to affect CAD has not been fully evaluated. Here, we investigated the association between TyG index and THs and further studied the impacts of TyG index and THs on CAD in euthyroid.

Methods

Subjects (1,297) with euthyroid who underwent selective coronary angiography (CAG) were enrolled in the present study, including 893 patients with CAD and 404 controls. The association between TyG index and THs were analyzed by linear regression models. Multivariate logistic regression analysis was used to evaluate the interaction of TyG and THs with the risk of CAD. According to the cutoff value of free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), and TyG index, the patients were respectively separated into four groups: low TyG/FT3 (low or high), high TyG/FT3 (low or high), low TyG/FT4 (low or high), high TyG/FT4 (low or high), low TyG/TSH (low or high), high TyG/TSH (low or high).

Results

The baseline analysis showed that FT4 level differs among the three groups according to the tertile of the TyG index. Multiple linear regression analysis revealed decreased serum FT3 level and serum FT4 level as an independent risk factor for elevated TyG index. After adjusting for confounding variables, multiple logistic regression analysis showed that patients with lower TyG index and higher FT3 level had an important protective effect on CAD when considering patients with lower TyG index and FT3 level as reference(OR = 0.536, 95% CI: 0.369-0.778, P = 0.001). Patients with higher TyG index and FT4 level (lower or higher) had a significantly increased risk of CAD (OR 1.656, 95% CI: 1.117-2.455; OR = 1.920, 95% CI: 1.279-2.848, respectively). The area under the curve for the combined diagnosis of CAD by TyG index and FT3 level is 0.615.

Conclusions

These findings suggest that TyG is independently negatively correlated with FT3 or FT4 in euthyroid. In addition, there was a significant interaction between TyG index and THs on the risk of CAD.

Relationship of triglyceride-glucose index with cardiometabolic multi-morbidity in China: evidence from a national survey

BACKGROUND

Cardiometabolic multi-morbidity (CMM) is emerging as a global healthcare challenge and a pressing public health concern worldwide. Previous studies have principally focused on identifying risk factors for individual cardiometabolic diseases, but reliable predictors of CMM have not been identified. In the present study, we aimed to characterize the relationship of triglyceride-glucose (TyG) index with the incidence of CMM.

METHODS

We enrolled 7,970 participants from the China Health and Retirement Longitudinal Study (CHARLS) and placed them into groups according to quartile of TyG index. The endpoint of interest was CMM, defined as the presence of at least two of the following: stroke, heart disease, and diabetes mellitus. Cox regression models and multivariable-adjusted restricted cubic spline (RCS) curves were used to evaluate the relationship between TyG index and CMM.

RESULTS

In total, 638 (8.01%) incident cases of CMM were recorded among the participants who did not have CMM at baseline (2011) during a median follow-up of 84 months (interquartile range, 20‒87 months). The incidences of CMM for the participants in quartiles (Q) 1-4 of TyG index were 4.22%, 6.12%, 8.78%, and 12.60%, respectively. A fully adjusted Cox model showed that TyG index was closely associated with the incidence of CMM: the hazard ratio (HR) [95% confidence interval (CI)] for each 1.0-unit increment in TyG index for CMM was 1.54 (1.29-1.84); and the HRs (95% CIs) for Q3 and Q4 (Q1 as reference) of the TyG index for CMM were 1.41 (1.05-1.90) and 1.61 (1.18-2.20), respectively. The association of TyG index with the incidence of CMM was present in almost all the subgroups, and persisted in the sensitivity analyses and additional analyses. Multivariable-adjusted RCS analysis revealed a significant dose-response relationship of TyG index with the risk of CMM (overall P < 0.001; non-linear P = 0.129).

CONCLUSIONS

We found that a high TyG index is associated with a higher risk of incident CMM. This finding may have significance for clinical practice and facilitate the creation of a personalized prevention strategy that involves monitoring the TyG index.

Combination of the triglyceride-glucose index and EuroSCORE II improves the prediction of long-term adverse outcomes in patients undergoing coronary artery bypass grafting

AIMS

We aimed to investigate the independent and combined association of the triglyceride-glucose (TyG) index and EuroSCORE II with major adverse cardiovascular event (MACE) after coronary artery bypass grafting (CABG), and examine whether the addition of the TyG index improves the predictive performance of the EuroSCORE II.

MATERIALS AND METHODS

This study included 1013 patients who underwent CABG. The primary endpoint was MACE, which was defined as the composite of all-cause death, repeat coronary artery revascularisation, non-fatal myocardial infarction and non-fatal stroke. The patients were grouped by the TyG index and EuroSCORE II tertiles and the combination of these risk indicators.

RESULTS

During the follow-up, 211 individuals developed MACE. Elevated levels of the TyG index and EuroSCORE II were associated with an increased risk of MACE. The hazard ratio [95% confidence interval (CI)] was 3.66 (2.34-5.73) in patients with the highest tertile of the TyG index and EuroSCORE II. Compared with the EuroSCORE II alone, combining the TyG index with EuroSCORE II achieved a better predictive performance [C-statistic increased 0.032, p < 0.001; continuous net reclassification improvement (NRI) (95% CI): 0.364 (0.215-0.514), p < 0.001; integrated discrimination improvement (IDI) (95% CI): 0.015 (0.007-0.023), p < 0.001, Akaike's information criteria (AIC) and Bayesian information criterion (BIC) decreased, and the likelihood ratio test, p < 0.001].

CONCLUSIONS

The TyG index and EuroSCORE II are independently associated with poor prognosis. Furthermore, the TyG index is an important adjunct to the EuroSCORE II for improving risk stratification and guiding early intervention among post-CABG patients.

Triglyceride-glucose index in the prediction of adverse cardiovascular events in patients without diabetes mellitus after coronary artery bypass grafting: a multicenter retrospective cohort study

BACKGROUND

The triglyceride-glucose (TyG) index has been evaluated as a reliable surrogate for insulin resistance (IR) and has been proven to be a predictor of poor outcomes in patients with cardiovascular diseases. However, data are lacking on the relationship of the TyG index with prognosis in nondiabetic patients who underwent coronary artery bypass grafting (CABG). Thus, the purpose of our current study was to investigate the potential value of the TyG index as a prognostic indicator in patients without diabetes mellitus (DM) after CABG.

METHODS

This multicenter, retrospective cohort study involving 830 nondiabetic patients after CABG from 3 tertiary public hospitals from 2014 to 2018. Kaplan-Meier survival curve analysis was conducted followed by the log-rank test. Cox proportional hazards regression models were used to explore the association between the TyG index and major adverse cardiovascular events (MACEs). The incremental predictive power of the TyG index was evaluated with C-statistics, continuous net reclassification improvement (NRI) and integrated discrimination improvement (IDI).

RESULTS

An incrementally higher TyG index was associated with an increasingly higher cumulative incidence of MACEs (log-rank test, p < 0.001). The hazard ratio (95% CI) of MACEs was 2.22 (1.46-3.38) in tertile 3 of the TyG index and 1.38 (1.18-1.62) per SD increase in the TyG index. The addition of the TyG index yielded a significant improvement in the global performance of the baseline model [C-statistic increased from 0.656 to 0.680, p < 0.001; continuous NRI (95% CI) 0.269 (0.100-0.438), p = 0.002; IDI (95% CI) 0.014 (0.003-0.025), p = 0.014].

CONCLUSIONS

The TyG index may be an independent factor for predicting adverse cardiovascular events in nondiabetic patients after CABG.

The metabolic score for insulin resistance in the prediction of major adverse cardiovascular events in patients after coronary artery bypass surgery: a multicenter retrospective cohort study

BACKGROUND

The metabolic score for insulin resistance (METS-IR) is a simple, convenient, and reliable marker for resistance insulin (IR), which has been regarded as a predictor of cardiovascular disease (CVD) and cardiovascular events. However, few studies examined the relationship between METS-IR and prognosis after coronary artery bypass graft (CABG). This study aimed to investigate the potential value of METS-IR as a prognostic indicator for the major adverse cardiovascular events (MACE) in patients after CABG.

METHOD

1100 CABG patients were enrolled in the study, including 760 men (69.1%) and 340 women (30.9%). The METS-IR was calculated as Ln [(2 × FPG (mg/dL) + fasting TG (mg/dL)] × BMI (kg/m²)/Ln [HDL-C (mg/dL)]. The primary endpoint of this study was the occurrence of major adverse cardiovascular events (MACE), including a composite of all-cause death, non-fatal myocardial infarction (MI), coronary artery revascularization, and stroke.

RESULT

The following-up time of this study was 49-101 months (median, 70 months; interquartile range, 62-78 months). During the follow-up period, there were 243 MACEs (22.1%). The probability of cumulative incidence of MACE increased incrementally across the quartiles of METS-IR (log-rank test, p < 0.001). Multivariate Cox regression analysis demonstrated a hazard ratio (95% CI) of 1.97 (1.36-2.86) for MACE in quartile 4 compared with participants in quartile 1. The addition of the METS-IR to the model with fully adjusting variables significantly improved its predictive value [C-statistic increased from 0.702 to 0.720, p < 0.001, continuous net reclassification improvement (NRI) = 0.305, < 0.001, integrated discrimination improvement (IDI) = 0.021, p < 0.001].

CONCLUSION

METS-IR is an independent and favorable risk factor for predicting the occurrence of MACE and can be used as a simple and reliable indicator that can be used for risk stratification and early intervention in patients after CABG.

Association between non-insulin-based insulin resistance indices and cardiovascular events in patients undergoing percutaneous coronary intervention: a retrospective study

BACKGROUND

Insulin resistance (IR) has been confirmed that getting involved in the pathophysiological process of cardiovascular diseases (CVD). Recently, increasing evidence suggests metabolic score for insulin resistance (METS-IR), triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, triglyceride and glucose (TyG) index, triglyceride glucose-body mass (TyG-BMI) index are simple and reliable surrogates for IR. However, their abilities in predicting cardiovascular outcomes in patients undergoing percutaneous coronary intervention (PCI) are not well explored. Therefore, this study aimed to investigate the association and evaluate the predictive performance of each index.

METHODS

A total of 2533 consecutive participants undergoing PCI were included in this study, and the data from 1461 patients were used to determine the correlation of these non-insulin-based IR indices with major adverse cardiac and cerebrovascular events (MACCEs) via performing the multivariate logistic models and restricted cubic splines (RCS).

RESULTS

During a median of 29.8 months follow-up, 195 cases of 1461 patients experienced incident MACCEs. In the overall population, both univariate and multivariate logistic regression analyses indicated no statistically significant connection between these IR indices and MACCEs. Subgroup analyses revealed significant interactions between age subgroups and TyG-BMI index, as well as METS-IR, and between sex subgroups and TyG index. In elderly patients, per 1.0-SD increment in TyG-BMI index and METS-IR had a significant association with MACCEs, with odds ratios (ORs) [95% confidence interval (CI)] of 1.24 (1.02-1.50) and 1.27 (1.04-1.56), respectively (both P < 0.05). Moreover, in female patients, all the IR indices showed significant associations with MACCEs. Multivariable-adjusted RCS curves demonstrated a linear relationship between METS-IR and MACCEs in elderly and female patients, respectively. However, all the IR indices failed to enhance the predictive performance of the basic risk model for MACCEs.

CONCLUSION

All the four IR indices showed a significant association with MACCEs in female individuals, whereas only TyG-BMI index and METS-IR showed associations in elderly patients. Although the inclusion of these IR indices did not improve the predictive power of basic risk model in either female or elderly patients, METS-IR appears to be the most promising index for secondary prevention of MACCEs and risk stratification in patients undergoing PCI.

The synergistic effect of the triglyceride-glucose index and serum uric acid on the prediction of major adverse cardiovascular events after coronary artery bypass grafting: a multicenter retrospective cohort study

BACKGROUND

Elevated serum uric acid (SUA) is regarded as a risk factor for the development of cardiovascular diseases. Triglyceride-glucose (TyG) index, a novel surrogate for insulin resistance (IR), has been proven to be an independent predictor for adverse cardiac events. However, no study has specifically focused on the interaction between the two metabolic risk factors. Whether combining the TyG index and SUA could achieve more accurate prognostic prediction in patients undergoing coronary artery bypass grafting (CABG) remains unknown.

METHODS

This was a multicenter, retrospective cohort study. A total of 1225 patients who underwent CABG were included in the final analysis. The patients were grouped based on the cut-off value of the TyG index and the sex-specific criteria of hyperuricemia (HUA). Cox regression analysis was conducted. The interaction between the TyG index and SUA was estimated using relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (SI). The improvement of model performance yielded by the inclusion of the TyG index and SUA was examined by C-statistics, net reclassification improvement (NRI) and integrated discrimination improvement (IDI). The goodness-of-fit of models was evaluated using the Akaike information criterion (AIC), Bayesian information criterion (BIC) and χ² likelihood ratio test.

RESULTS

During follow-up, 263 patients developed major adverse cardiovascular events (MACE). The independent and joint associations of the TyG index and SUA with adverse events were significant. Patients with higher TyG index and HUA were at higher risk of MACE (Kaplan-Meier analysis: log-rank P < 0.001; Cox regression: HR = 4.10; 95% CI 2.80-6.00, P < 0.001). A significant synergistic interaction was found between the TyG index and SUA [RERI (95% CI): 1.83 (0.32-3.34), P = 0.017; AP (95% CI): 0.41 (0.17-0.66), P = 0.001; SI (95% CI): 2.13 (1.13-4.00), P = 0.019]. The addition of the TyG index and SUA yielded a significant improvement in prognostic prediction and model fit [change in C-statistic: 0.038, P < 0.001; continuous NRI (95% CI): 0.336 (0.201-0.471), P < 0.001; IDI (95% CI): 0.031 (0.019-0.044), P < 0.001; AIC: 3534.29; BIC: 3616.45; likelihood ratio test: P < 0.001).

CONCLUSIONS

The TyG index interacts synergistically with SUA to increase the risk of MACE in patients undergoing CABG, which emphasizes the need to use both measures concurrently when assessing cardiovascular risk.

A high triglyceride-glucose index associated with adverse cardiovascular events in patients with type 2 diabetes mellitus and chronic total occlusion after percutaneous coronary intervention

Triglyceride-glucose index (TyG index) is a reliable surrogate marker of insulin resistance, associated with morbidity and prognosis of cardiovascular disease. However, its predictive value for cardiovascular events in patients with type 2 diabetes mellitus (T2DM) and chronic total occlusion (CTO) after percutaneous coronary intervention (PCI) has not been studied. Here, we retrospectively enrolled 681 patients with T2DM and CTO after PCI. Patients were divided into two groups based on a median TyG index of 9.02. The TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The primary observational end point was the composite of overall death, nonfatal myocardial infarction, and unplanned revascularization. The Multivariate Cox hazards regression analysis showed that the TyG index was significantly correlated with the primary end point (hazard ratio = 1.699, 95% confidence interval 1.254-2.303, p = 0.001). The addition of TyG to a baseline risk model had an incremental effect on the predictive value for the primary end point (area under the curve: TyG index vs baseline model, 0.693 vs 0.663, comparison p = 0.040; integrated discrimination improvement = 0.049, p = 0.020). The TyG index might be a predictor of adverse cardiovascular events. Moreover, adding the TyG index into a baseline risk model had a cumulative effect on the predictive potential for the primary end point.

Non-insulin-based insulin resistance indexes in predicting severity for coronary artery disease

BACKGROUND

Triglyceride and glucose (TyG) index, triglyceride glucose-body mass (TyG-BMI) index, triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, and metabolic score for insulin resistance (METS-IR) are considered simple and reliable indicators of insulin resistance (IR). Although they have been associated with coronary artery disease (CAD), evidence supporting this is limited. Here, this is the first study to demonstrate the relationship between TyG-BMI index and CAD severity. The performance of the four non-insulin-based IR indexes in predicting CAD severity was explored.

METHODS

We retrospectively analyzed 485 CAD patients between August 2020 and August 2021 in China, who were assigned into single- and multi-vessel CAD groups according to the coronary angiography (CAG) results. All patients were stratified into groups based on the tertiles of the TyG index, TyG-BMI index, TG/HDL-C ratio, and METS-IR.

RESULTS

Patients in the multi-vessel CAD group had significantly higher TyG index, TyG-BMI index, TG/HDL-C ratio and METS-IR than those in the single-vessel CAD group. After adjusting for confounding factors, these four indicators were significantly associated with the risk of multi-vessel CAD. Notably, the highest tertile of TyG index, TyG-BMI index, TG/HDL-C ratio and METS-IR were significantly associated with the risk of multi-vessel CAD compared to participants in the lowest tertile. We also constructed receiver operating characteristic (ROC) curve, to assess CAD severity. The area under the curve (AUC) of the ROC plots was 0.673 (95% CI 0.620-0.726; P < 0.001) for TyG index, while those for the TyG-BMI index, TG/HDL-C ratio, and METS-IR were 0.704 (95% CI 0.652-0.755; P < 0.001), 0.652 (95% CI 0.597-0.708; P < 0.001), and 0.726 (95% CI 0.677-0.775; P < 0.001), respectively.

CONCLUSIONS

TyG-BMI index is not only significantly associated with CAD severity, but is also an independent risk factor for multi-vessel CAD. The TyG index, TyG-BMI index, TG/HDL-C ratio, and METS-IR could be valuable predictors of CAD severity. Among the four non-insulin-based IR indexes, METS-IR had the highest predictive value, followed by TyG-BMI index.

Association between triglyceride glucose index and worsening heart failure in significant secondary mitral regurgitation following percutaneous coronary intervention

BACKGROUND

The triglyceride glucose (TyG) index is an alternative to insulin resistance (IR) as an early indicator of worsening heart failure (HF). Patients with secondary mitral regurgitation (sMR) often experience progressive deterioration of cardiac function. This study aimed to investigate the relationship between the TyG index and worsening of HF in significant sMR (grade  ≥ 2) following percutaneous coronary intervention (PCI).

METHODS

This study enrolled participants with significant sMR following PCI from a multicenter cohort study. The patients were divided into the following 3 groups according to tertiles of TyG index: T1, TyG ≤ 8.51; T2, TyG > 8.51 to ≤ 8.98; and T3, TyG > 8.98. The main clinical outcome was worsening HF including unplanned rehospitalization or unscheduled physician office/emergency department visit due to HF and unplanned mitral valve surgery.

RESULTS

A total of 922 patients (mean ± SD age, 64.1 ± 11.0 years; 79.6% male) were enrolled. The incidence of worsening HF was 15.5% in T1, 15.7% in T2, and 26.4% in T3. In the multivariable model, the highest TyG tertile (T3 group) was more strongly correlated with worsening HF than the lowest tertile (T1 group) after adjusting for confounders (adjusted hazard ratio, 2.44; 95% confidence interval, 1.59-3.72; P < 0.001). The addition of TyG to risk factors such as N-terminal pro brain natriuretic peptide and clinical models improved the predictive ability of TyG for worsening HF.

CONCLUSIONS

Elevated preprocedural TyG index is a significant and independent risk factor for worsening HF in sMR following PCI that can be used for risk stratification.

Predictive worth of estimated glucose disposal rate: evaluation in patients with non-ST-segment elevation acute coronary syndrome and non-diabetic patients after percutaneous coronary intervention

BACKGROUND

Measurement of estimated glucose disposal rate (eGDR) has been demonstrated to be an indicator of insulin resistance (IR) and a risk sign for long-term outcomes in those with ischemic heart disease and type 2 diabetes mellitus (T2DM) having coronary artery bypass grafting (CABG). After elective percutaneous coronary intervention (PCI), the usefulness of eGDR for prognosis in those with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and non-diabetes is yet unknown.

METHODS

1510 NSTE-ACS patients with non-diabetes who underwent elective PCI in 2015 (Beijing Anzhen Hospital) were included in this study. Major adverse cardio-cerebral events (MACCEs), such as all-cause mortality, non-fatal myocardial infarction, non-fatal ischemic stroke, and also ischemia-driven revascularization, were the main outcome of follow-up. The average number of follow-up months was 41.84.

RESULTS

After multivariate Cox regression tests with confounder adjustment, the occurrence of MACCE in the lower eGDR cluster was considerably higher than in the higher eGDR cluster, demonstrating that eGDR is an independent prognostic indicator of MACCEs. In particular, as continuous variate: hazard ratio (HR) of 1.337, 95% confidence interval (CI) of 1.201-1.488, P < 0.001. eGDR improves the predictive power of usual cardiovascular risk factors for the primary endpoint. Specifically, the results for the area under the receiver operating characteristic (ROC) curve, this is AUC, were: baseline model + eGDR 0.699 vs. baseline model 0.588; P for contrast < 0.001; continuous net reclassification improvement (continuous-NRI) = 0.089, P < 0.001; and integrated discrimination improvement (IDI) = 0.017, P < 0.001.

CONCLUSION

Low eGDR levels showed a strong correlation with poor NSTE-ACS prognosis for nondiabetic patients undergoing PCI.

Insulin Resistance and Vitamin D Deficiency: A Link Beyond the Appearances

Vitamin D is a steroid hormone that plays a key role in the regulation of body homeostasis, including cardiovascular function. Although the chronic deficiency of vitamin D is associated with cardiovascular risk factors, as well as with an adverse prognosis, randomized controlled trials have failed in demonstrating that dietary vitamin D supplementation could ameliorate the prognosis of patients with cardiovascular diseases, and suggested that vitamin D deficiency is the expression of the effects of other determinants of cardiovascular risk. Thus, the supplementation of vitamin D is not sufficient to improve the cardiovascular risk profile and prognosis. Insulin resistance is a complex phenomenon that plays a key role in the pathogenesis of conventional cardiovascular risk factors. Interestingly, defects of vitamin D and insulin resistance have a superimposable epidemiological distribution. According to the common view, Insulin resistance is considered the direct or indirect consequence of vitamin D deficiency. However, it is also reasonable to speculate that the deficit or the impaired action of vitamin D, in some circumstances, could be the result of the same pathogenic mechanisms responsible of insulin resistance development. In this case, vitamin D deficiency could be considered an epiphenomenon of insulin resistance. Insulin resistance is a reversible condition, being possibly ameliorated by physical activity and hypocaloric diets. Notably, both physical exercise and energy-restricted dietary regimens are associated with an increase of vitamin D levels. These findings indicate that improving insulin resistance condition is a necessary step to ameliorate vitamin D supplementation-based strategies in cardiovascular prevention.

Prognostic Significance of Triglyceride-Glucose Index for Adverse Cardiovascular Events in Patients With Coronary Artery Disease: A Systematic Review and Meta-Analysis

Background: Insulin resistance (IR) represents a critical regulator in the development and progress of coronary artery disease (CAD). Triglyceride-glucose (TyG) index, a novel surrogate biomarker of IR, has been implicated in several cardiovascular diseases. Accordingly, we conduct a meta-analysis to elucidate the relationship between TyG index and adverse cardiovascular events in patients with CAD.

Methods: To identify the studies examining the predictive capacity of the TyG index for adverse cardiovascular events in the setting of CAD, we performed a comprehensive literature retrieval of Scopus, PubMed, EMBASE, and Web of Science, from the inception of databases to October 5, 2021. We pooled the adjusted hazard ratio (HR) along with 95% CI using a random-effects model. The primary outcome was a composite of major adverse cardiovascular events (MACEs), including all-cause death, cardiovascular death (CV death), myocardial infarction (MI), stroke, hospitalization for unstable angina or heart failure, and revascularization. The secondary outcomes were all-cause death, CV death, MI, stroke, and revascularization. Additionally, we conducted subgroup analyses stratified by diabetes status, age, body mass index (BMI), low-density lipoprotein cholesterol (LDL-C), category of TyG index, sample size, follow-up duration, and study design.

Results: About 12 studies involving 28,795 patients with CAD were finally taken into the quantitative analysis. Our findings showed that there was a 2.14-fold higher risk of MACEs among CAD populations in the highest TyG group compared with those in the lowest TyG group (HR: 2.14, 95% CI: 1.69–2.71, P < 0.001). A greater risk of MACEs was observed in participants with higher BMI than those with lower BMI (P = 0.03 for interaction). In the analysis of secondary outcomes, we also observed a markedly increased risk of MI, stroke, and revascularization in the highest TyG group compared with the lowest TyG group. No evidence of a significant association between TyG index and CV mortality or all-cause mortality in patients with CAD was identified.

Conclusions: The elevated TyG index is a promising predictive factor of adverse cardiovascular events in patients with CAD.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO, identifier: CRD42021228521.

Triglyceride-Glucose Index as a Surrogate Marker of Insulin Resistance for Predicting Cardiovascular Outcomes in Nondiabetic Patients with Non-ST-Segment Elevation Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

Aim: The triglyceride-glucose index (TyG index) is proposed as a surrogate parameter for insulin resistance (IR) and, when elevated, is related to increased cardiovascular risks. Whether the TyG index is of great value in predicting adverse prognosis for individuals diagnosed with non-ST-segment elevation acute coronary syndrome (NSTE-ACS), who received elective percutaneous coronary intervention (PCI), and without recognized diabetes remains unclear.

Methods: Overall, 1,510 subjects diagnosed with NSTE-ACS, who received elective PCI, and without recognized diabetes were enrolled in the current study. All participants received a routine follow-up after discharge. The TyG index was obtained from the following equation: napierian logarithmic (ln) [fasting triglyceride (TG, mg/dL)×fasting blood glucose (FBG, mg/dL)/2]. Adverse cardiovascular events included all-cause death, nonfatal myocardial infarction (MI), nonfatal ischemic stroke, and ischemia-driven revascularization, composite of which was defined as the primary endpoint.

Results: Overall, 316 (20.9%) endpoint events were documented during a 48-month follow-up. Despite adjusting for confounding variates, the TyG index remains to be a significant risk predictor for the primary endpoint, with a hazard ratio (HR) [95% confidence interval (CI)] of 2.433 (1.853-3.196) ( P ＜0.001). A significant enhancement on the predictive performance for the primary endpoint emerged when adding the TyG index into a baseline model [area under the receiver-operating characteristic (ROC) curve (AUC), 0.835 for baseline model vs. 0.853 for baseline model＋TyG index, P ＜0.001; net reclassification improvement (NRI), 0.194, P ＜0.001; integrated discrimination improvement (IDI), 0.023, P =0.007].

Conclusions: The TyG index is an independent risk predictor for adverse cardiovascular events in nondiabetic subjects diagnosed with NSTE-ACS and who received elective PCI. Further prospective studies are needed to verify these findings.

Association of the triglyceride-glucose index and major adverse cardiac and cerebrovascular events in female patients undergoing percutaneous coronary intervention with drug-eluting stents: A retrospective study

AIMS

We aimed to examine the association between the Triglyceride-glucose (TyG) index and clinical outcome of percutaneous coronary intervention (PCI) patients with drug-eluting stents (DESs).

METHODS

From July 2009 to August 2011, 2533 patients who underwent at least one PCI with DESs were enrolled to determine the relationship between the TyG index and MACCEs with a 29.8-month follow-up. In addition, the Logistic regression proportional hazard model was applied to assess the prognostic value of the TyG index.

RESULTS

The MACCEs was associated with, history of heart failure (p = 0.049), third degree AVB (p = 0.008) and stroke (p = 0.033), SBP (p < 0.001), DBP (p = 0.001), number of diseased vessels, location of target lesions, characteristics of lesion, number of treated vessels, number of stents, length of stents (p = 0.003) and stent diameter (p < 0.001). The multivariate Logistic regression analysis revealed that the TyG index was an independent prognostic factor for MACCEs in female patients (OR = 1.68, 95 %CI = 1.12-2.54, p = 0.013) but not in male (OR = 0.95, 95 %CI = 0.74-1.21, p = 0.657).

CONCLUSION

The TyG index was independently associated with MACCEs in female patients undergoing PCI with DESs, but not in men.

Proprotein Convertase Subtilisin/Kexin Type 9 and Systemic Inflammatory Biomarker Pentraxin 3 for Risk Stratification Among STEMI Patients Undergoing Primary PCI

Background and Aim

The aim of prospective study was to determine the prognostic value of combined measures of plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) and pentraxin 3 (PTX3) according to the culprit-plaque morphology (plaque rupture versus plaque erosion) in relation to the in patients with acute ST-elevated myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention.

Methods

A total of 434 patients with STEMI aged ≥18 years who underwent pre-intervention OCT imaging of culprit lesions between March 2017 and March 2019 were enrolled. Finally, 235 patients who meet the inclusion criteria were enrolled and the cohort was divided into 3 groups according to PCSK9 and PTX3 levels: group A: PCSK9 < median and Pentraxin 3 (N = 72/30.6%); group B: PCSK9 ≥ median or Pentraxin 3≥ median (N = 91/38.7%); group C: PCSK9 ≥ median and Pentraxin 3≥ median (N = 72/30.6%). MACEs were defined as a composite of all-cause death, myocardial infarction (MI) recurrence, and ischemic stroke, revascularization and heart failure.

Outcomes

During a median follow-up of 2.01 years, 50 patients has occurred MACE. Two-year MACE was higher in group C (23/31.9%) than in group B (16/17.6%) and group A (11/15.3%) (p = 0.028). There was a correlation between PCSK9 and PTX3 (r = 0.302, p < 0.003). In multivariable analysis adjusted for age, gender, risk factors, and serum indexes, being in group C remained independently associated with an increased risk of MACE (hazard ratio [HR]: 2.90; p = 0.010), and group B tended to have higher MACE (HR: 1.76; p = 0.172) compared with group A. Among patients with plaque erosion by OCT, group C was independently associated with an increased risk of MACE (HR: 9.04; p = 0.048) after fully adjustment. However, the significant association was absence among patients with plaque rupture.

Conclusion and Relevance

This study demonstrated the usefulness of combined measures of PCSK9 and PTX3 to enhance risk stratification in patients with STEMI especially among patients with plaque erosion. Patients with elevation of both PCSK9 and PTX3 had a markedly increased risk of MACE.

Comparison of various insulin resistance surrogates on prognostic prediction and stratification following percutaneous coronary intervention in patients with and without type 2 diabetes mellitus

BACKGROUND

Insulin resistance (IR), evaluation of which is difficult and complex, is closely associated with cardiovascular disease. Recently, various IR surrogates have been proposed and proved to be highly correlated with IR assessed by the gold standard. It remains indistinct whether different IR surrogates perform equivalently on prognostic prediction and stratification following percutaneous coronary intervention (PCI) in non-ST-segment elevation acute coronary syndrome (NSTE-ACS) patients with and without type 2 diabetes mellitus (T2DM).

METHODS

The present study recruited patients who were diagnosed with NSTE-ACS and successfully underwent PCI. IR surrogates evaluated in the current study included triglyceride-glucose (TyG) index, visceral adiposity index, Chinese visceral adiposity index, lipid accumulation product, and triglyceride-to-high density lipoprotein cholesterol ratio, calculations of which were conformed to previous studies. The observational endpoint was defined as the major adverse cardiovascular and cerebrovascular events (MACCE), including cardiac death, non-fatal myocardial infarction, and non-fatal ischemic stroke.

RESULTS

2107 patients (60.02 ± 9.03 years, 28.0% female) were ultimately enrolled in the present study. A total of 187 (8.9%) MACCEs were documented during the 24-month follow-up. Despite regarding the lower median as reference [hazard ratio (HR) 3.805, 95% confidence interval (CI) 2.581-5.608, P < 0.001] or evaluating 1 normalized unit increase (HR 1.847, 95% CI 1.564-2.181, P < 0.001), the TyG index remained the strongest risk predictor for MACCE, independent of confounding factors. The TyG index showed the most powerful diagnostic value for MACCE with the highest area under the receiver operating characteristic curve of 0.715. The addition of the TyG index, compared with other IR surrogates, exhibited the maximum enhancement on risk stratification for MACCE on the basis of a baseline model (Harrell's C-index: 0.708 for baseline model vs. 0.758 for baseline model + TyG index, P < 0.001; continuous net reclassification improvement: 0.255, P < 0.001; integrated discrimination improvement: 0.033, P < 0.001). The results were consistent in subgroup analysis where similar analyses were performed in patients with and without T2DM, respectively.

CONCLUSION

The TyG index, which is most strongly associated with the risk of MACCE, can be served as the most valuable IR surrogate for risk prediction and stratification in NSTE-ACS patients receiving PCI, with and without T2DM.

Triglyceride glucose index combined with plaque characteristics as a novel biomarker for cardiovascular outcomes after percutaneous coronary intervention in ST-elevated myocardial infarction patients: an intravascular optical coherence tomography study

Background and aim

This prospective study explored plaque morphology according to the underlying culprit lesion pathology (rupture versus erosion) in relation to the triglyceride glucose (TyG) index in patients with acute ST-elevated myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention and optical coherence tomography (OCT) for culprit lesions to elucidate the effects of the TyG index and type of plaque on the incidence of major adverse cardiovascular events (MACEs).

Methods and outcomes

A total of 274 patients with STEMI aged ≥ 18 years who underwent pre-intervention OCT imaging of culprit lesions between March 2017 and March 2019 were enrolled. The TyG index was calculated using the formula ln[fasting TG (mg/dL) × fasting glucose (mg/dL)/2]. Patients with plaque rupture (PR) and plaque erosion (PE) were divided into three groups across the TyG tertiles. MACEs were defined as a composite of all-cause death, myocardial infarction (MI) recurrence, and ischaemic stroke.

In fully adjusted analyses, the middle tertile of TyG was significantly associated with greater rates of MACEs in patients with PR but not in those with PE (relative to the low tertile, HR [hazard ratio], 6.01; 95% confidence interval [CI], 1.25–28.88; P = 0.025). Cox regression models indicated a significantly higher HR for MACEs in patients in the middle tertile of TyG than in those in the low tertile of TyG after full additional adjustment (HR, 5.45; 95% CI, 1.10–27.09; P = 0.038). However, being in the high tertile of TyG independently and significantly increased the risk of major bleeding events among patients with PE (HR, 2.50; 95% CI, 1.11–5.65; P = 0.028). The area under the receiver operating characteristic curve for predicting MACEs to evaluate the diagnostic value of the TyG index combined with the morphological characteristics of plaque after full adjustment was 0.881 (sensitivity = 94.74%, specificity = 78.04%, cut-off level = 0.73). Kaplan–Meier curves were generated for the cumulative incidence of MACEs for up to a median of 1.98 years stratified by tertiles of TyG among the PR and PE subgroups. Among patients with PR, there were significant differences among the tertiles of TyG (p = 0.030).

Conclusion and relevance

Microstructural OCT features of culprit lesions in combination with the TyG index, a surrogate estimate of insulin resistance, can be used in clinical practice to support risk stratification and predict adverse events in patients with STEMI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01321-7.

Impact of Acute Insulin Resistance on Myocardial Blush in Non-Diabetic Patients Undergoing Primary Percutaneous Coronary Intervention

Background: Myocardial blush grading is considered to be a novel tool for assessment of coronary microvasculature and myocardial perfusion in patients undergoing coronary angiography and angioplasty, and its reduction identifies patients at high risk. Our study aimed to evaluate the association between acute insulin resistance and myocardial blush in non-diabetic patients with ST-segment elevation myocardial infarction (STEMI).

Methods: Two hundred forty non-diabetic patients with STEMI who underwent primary percutaneous coronary intervention were consecutively recruited. The relationship of homeostasis model assessment—estimated insulin resistance (HOMA-IR) to myocardial blush and in-hospital outcome was investigated.

Results: Higher HOMA-IR tertile was observed in obese patients, with hyperinsulinemia, had Killip class >1, with higher CPK-MB level and was correlated to impaired myocardial blush after adjusting for the other confounding risk factors. It was also concluded that higher HOMA-IR was independently associated with no/minimal myocardial blush after STEMI. Moreover, it was founded to be an independent predictor of pulmonary edema and impaired left ventricular systolic function.

Conclusion: This study revealed that acute insulin resistance was prevalent in non-diabetic patients with STEMI and was an independent predictor for post-infarction myocardial and microvascular injury and poor in-hospital outcome.

Trial Registration: The trial was registered at the registry of Clinicaltrials.gov, ClinicalTrials.gov Identifier: NCT04651842, Date of registration: 2^nd December 2020 Registry URL, https://clinicaltrials.gov/ct2/show/NCT04385589?cond=Dapagliflozin+in+diabetic+patients&cntry=EG&draw=2&rank=1.

Modulation of insulin resistance by renin angiotensin system inhibitors: implications for cardiovascular prevention

Insulin resistance (IR) and the related hyperinsulinamia play a key role in the genesis and progression of the continuum of cardiovascular (CV) disease. Thus, it is reasonable to pursue in primary and secondary CV prevention, the pharmacological strategies that are capable to interfere with the development of IR. The renin-angiotensin-aldosterone system (RAAS) plays an important role in the pathogenesis of IR. In particular, angiotensin II (Ang II) through the generation of reactive oxygen species, induces a low grade of inflammation, which impairs the insulin signal transduction. The angiotensin converting enzyme (ACE) inhibitors are effective not only as blood pressure-lowering agents, but also as modulators of metabolic abnormalities. Indeed, experimental evidence indicates that in animal models of IR, ACE inhibitors are capable to ameliorate the insulin sensitivity. The Ang II receptor blockers (ARBs) modulate the peroxisome proliferator-activated receptor (PPAR)-γ activity. PPARâ€"γ is a transcription factor that controls the gene expression of several key enzymes of glucose metabolism. A further mechanism that accounts for the favorable metabolic properties of ARBs is the capability to modulate the hypothalamicâ€"pituitary-adrenal (HPA) axis. The available clinical evidence is consistent with the concept that both ACE inhibitors and ARBs are able to interfere with the development of IR and its consequences like type 2 diabetes. In addition, pharmacological inhibition of the RAAS has favourable effects on dyslipidaemias, metabolic syndrome and obesity. Therefore, the pharmacological antagonism of the RAAS, nowadays, represents the first choice in the prevention of cardio-metabolic diseases.

Impact of Hyperinsulinemia on Long-Term Clinical Outcomes of Percutaneous Coronary Intervention in Patients without Diabetes Who Have Acute Myocardial Syndrome

BACKGROUND AND OBJECTIVES

Hyperinsulinemia plays a key role in the development of cardiovascular impairment in patients with metabolic syndrome. The aim of this study was to evaluate the influence of hyperinsulinemia on long-term clinical outcomes of percutaneous coronary intervention (PCI) in patients without diabetes mellitus who have acute myocardial syndrome (ACS).

METHODS

Between March 2016 and January 2019, we enrolled 468 patients with ACS and without diabetes mellitus who received primary PCI. Patients were divided into a low-insulin group (n = 157), medium-insulin group (n = 154), and high-insulin group (n = 157) according to tertiles of fasting insulin level. The primary endpoint was major adverse cardiac events (MACE; all-cause death, non-fatal myocardial infarction, target vessel revascularization [TVR]) at 24 months. The secondary endpoint was angina hospitalization.

RESULTS

Patients in the high-insulin group had an unfavorable prognosis, with a higher rate of MACE (34.39%) than the low-insulin group (22.29%) and medium-insulin group (23.37%) at 24 months (P < 0.05). This difference was mainly driven by the increase in TVR. The high-insulin group also had a higher rate of angina hospitalization than the low-insulin group. Cox proportional hazards regression showed that high-insulin level (hazard ratio [HR] 1.870, 95% confidence interval [CI] 1.202-2.909), small-vessel lesion (HR 1.713, 95% CI 1.111-2.642), bifurcation lesion (HR 3.394, 95% CI 2.033-5.067), SYNTAX score (HR 1.084, 95% CI 1.039-1.130), and stent length (HR 1.017, 95% CI 1.002-1.032) increased the incidence of MACE in patients with ACS and without diabetes who underwent PCI.

CONCLUSION

Hyperinsulinemia might be a valid predictor of clinical outcomes in patients with ACS undergoing PCI.

Impacts of triglyceride-glucose index on prognosis of patients with type 2 diabetes mellitus and non-ST-segment elevation acute coronary syndrome: results from an observational cohort study in China

BACKGROUND

The relationship between triglyceride-glucose index (TyG index) and the prevalence and prognosis of cardiovascular disease has been confirmed by former studies. However, it remains uncertain whether TyG index has a prognostic impact in patients with type 2 diabetes mellitus (T2DM) and non-ST-segment elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI).

METHODS

The study retrospectively enrolled 798 patients (mean age: 60.9 ± 8.3 years; 68.3% men) with T2DM and NSTE-ACS who underwent PCI at Beijing Anzhen Hospital from January to December 2015. TyG index was calculated as previously reported: ln [fasting TGs (mg/dL) * FBG (mg/dL)/2]. The primary endpoint was a composite of adverse events as follows: all-cause death, non-fatal myocardial infarction (MI) and ischemia-driven revascularization.

RESULTS

TyG index was significantly higher in patients with a primary endpoint event compared with those without. Multivariate Cox proportional hazards analysis showed that 1-unit increase of TyG index was independently associated with higher risk of primary endpoint, independent of other risk factors [hazard ratio (HR) 3.208 per 1-unit increase, 95% confidence interval (CI) 2.400-4.289, P < 0.001]. The addition of TyG index to a baseline risk model had an incremental effect on the predictive value for adverse prognosis [AUC: baseline risk model, 0.800 vs. baseline risk model + TyG index, 0.856, P for comparison < 0.001; category-free net reclassification improvement (NRI) 0.346, P < 0.001; integrated discrimination improvement (IDI) 0.087, P < 0.001].

CONCLUSIONS

Increased TyG index is a significant predictor of adverse prognosis in patients with T2DM and NSTE-ACS undergoing PCI. Further studies need to be performed to determine whether interventions for TyG index have a positive impact on improving clinical prognosis.

Triglyceride-glucose index predicts adverse cardiovascular events in patients with diabetes and acute coronary syndrome

BACKGROUND

The triglyceride-glucose index (TyG index) has been regarded as a reliable alternative marker of insulin resistance and an independent predictor of cardiovascular outcomes. Whether the TyG index predicts adverse cardiovascular events in patients with diabetes and acute coronary syndrome (ACS) remains uncertain. The aim of this study was to investigate the prognostic value of the TyG index in patients with diabetes and ACS.

METHODS

A total of 2531 consecutive patients with diabetes who underwent coronary angiography for ACS were enrolled in this study. Patients were divided into tertiles according to their TyG index. The primary outcomes included the occurrence of major adverse cardiovascular events (MACEs), defined as all-cause death, non-fatal myocardial infarction and non-fatal stroke. The TyG index was calculated as the ln (fasting triglyceride level [mg/dL] × fasting glucose level [mg/dL]/2).

RESULTS

The incidence of MACE increased with TyG index tertiles at a 3-year follow-up. The Kaplan-Meier curves showed significant differences in event-free survival rates among TyG index tertiles (P = 0.005). Multivariate Cox hazards regression analysis revealed that the TyG index was an independent predictor of MACE (95% CI 1.201-1.746; P < 0.001). The optimal TyG index cut-off for predicting MACE was 9.323 (sensitivity 46.0%; specificity 63.6%; area under the curve 0.560; P = 0.001). Furthermore, adding the TyG index to the prognostic model for MACE improved the C-statistic value (P = 0.010), the integrated discrimination improvement value (P = 0.001) and the net reclassification improvement value (P = 0.019).

CONCLUSIONS

The TyG index predicts future MACE in patients with diabetes and ACS independently of known cardiovascular risk factors, suggesting that the TyG index may be a useful marker for risk stratification and prognosis in patients with diabetes and ACS.

Association between insulin resistance, hyperglycemia, and coronary artery disease according to the presence of diabetes

This study evaluated the relationship of insulin resistance (IR) and glycemic control status to the presence and severity of coronary artery disease (CAD) according to diabetes. The relationship of IR parameters including homeostatic model assessment of IR (HOMA-IR), triglyceride-glucose (TyG) index, and triglyceride-to-high density lipoprotein cholesterol ratio (TG/HDL), and hemoglobin A1C (HbA1C) level to CAD and obstructive CAD was evaluated in 5,764 asymptomatic subjects who underwent coronary computed tomographic angiography. Non-diabetics (n = 4768) and diabetics (n = 996) were stratified into four groups based on the quartiles of HOMA-IR and the TyG index and were grouped based on the TG/HDL cut-offs of 3.5, respectively. CAD and obstructive CAD were defined as the presence of any plaques and plaques with ≥50% stenosis, respectively. The prevalence of CAD (59.0% vs. 39.0%) and obstructive CAD (15.0% vs. 6.6%) was higher in diabetic than in non-diabetic patients (p < 0.001, respectively). In non-diabetic patients, the adjusted odds ratio for both CAD and obstructive CAD significantly increased, but only with higher TyG index quartiles. Unlike non-diabetics, the adjusted odds ratio for obstructive CAD significantly increased in diabetic patients with a TG/HDL level ≥ 3.5. The HbA1C, rather than IR parameters, was independently associated with both CAD and obstructive CAD in diabetics. In conclusion, among IR parameters, TyG index was independently associated with the presence of CAD and obstructive CAD in non-diabetic patients. In contrast, the glycemic control status, rather than IR, was importantly related to both CAD and obstructive CAD in established diabetic patients.

Epigenetic processing in cardiometabolic disease

Albeit a consistent body of evidence supports the notion that genes influence cardiometabolic features and outcomes, the "non-genetic regulation" of this process is gaining increasing attention. Plastic chemical changes of DNA/histone complexes - known as epigenetic changes - critically determine gene activity by rapidly modifying chromatin accessibility to transcription factors. In this review, we describe the emerging role of chromatin modifications as fine tuners of gene transcription in adipogenesis, insulin resistance, macrophage polarization, immuno-metabolism, endothelial dysfunction and metabolic cardiomyopathy. Epigenetic processing participates in the dynamic interplay among different organs in the cardiometabolic patient. DNA methylation and post-translational histone modifications in both visceral and subcutaneous adipose tissue enable the transcription of genes implicated in lipo- and adipogenesis, inflammation and insulin resistance. Along the same line, complex networks of chromatin modifying enzymes are responsible for impaired nitric oxide bioavailability and defective insulin signalling in the vasculature, thus leading to reduced capillary recruitment and insulin delivery in the liver, skeletal muscle and adipose tissue. Furthermore, changes in methylation status of IL-4, IFNγ and Forkhead box P3 (Foxp3) gene loci are crucial for the polarization of immune cells, thus leading to adipose tissue inflammation and atherosclerosis. Cell-specific epigenetic information could advance our understanding of cardiometabolic processes, thus leading to individualized risk assessment and personalized therapeutic approaches in patients with cardiometabolic disturbances. The development of new chromatin modifying drugs indicates that targeting epigenetic changes is a promising approach to reduce the burden of cardiovascular disease in this setting.

Homeostasis Model Assessment of Insulin Resistance and Survival in Patients With Diabetes and Acute Coronary Syndrome

OBJECTIVE

Insulin resistance has been linked to development and progression of atherosclerosis and is present in most patients with type 2 diabetes. Whether the degree of insulin resistance predicts adverse outcomes in patients with type 2 diabetes and acute coronary syndrome (ACS) is uncertain.

DESIGN

The Effect of Aleglitazar on Cardiovascular Outcomes after Acute Coronary Syndrome in Patients with Type 2 Diabetes Mellitus trial compared the peroxisome proliferator-activated receptor-α/γ agonist aleglitazar with placebo in patients with type 2 diabetes and recent ACS. In participants not treated with insulin, we determined whether baseline homeostasis model assessment of insulin resistance (HOMA-IR; n = 4303) or the change in HOMA-IR on assigned study treatment (n = 3568) was related to the risk of death or major adverse cardiovascular events (cardiovascular death, myocardial infarction, and stroke) in unadjusted and adjusted models. Because an inverse association of HOMA-IR with N-terminal pro-B-type natriuretic peptide (NT-proBNP) has been described, we specifically examined effects of adjustment for the latter.

RESULTS

In unadjusted analysis, twofold higher baseline HOMA-IR was associated with lower risk of death [hazard ratio (HR): 0.79, 95% CI: 0.68 to 0.91, P = 0.002]. Adjustment for 24 standard demographic and clinical variables had minimal effect on this association. However, after further adjustment for NT-proBNP, the association of HOMA-IR with death was no longer present (adjusted HR: 0.99, 95% CI: 0.83 to 1.19, P = 0.94). Baseline HOMA-IR was not associated with major adverse cardiovascular events, nor was the change in HOMA-IR on study treatment associated with death or major adverse cardiovascular events.

CONCLUSIONS

After accounting for levels of NT-proBNP, insulin resistance assessed by HOMA-IR is not related to the risk of death or major adverse cardiovascular events in patients with type 2 diabetes and ACS.

Effect of pioglitazone on cardiometabolic profiles and safety in patients with type 2 diabetes undergoing percutaneous coronary artery intervention: a prospective, multicenter, randomized trial

Pioglitazone has superior antiatherosclerotic effects compared with other classes of antidiabetic agents, and there is substantial evidence that pioglitazone improves cardiovascular (CV) outcomes. However, there is also a potential risk of worsening heart failure (HF). Therefore, it is clinically important to determine whether pioglitazone is safe in patients with type 2 diabetes mellitus (T2DM) who require treatment for secondary prevention of CV disease, since they have an intrinsically higher risk of HF. This prospective, multicenter, open-label, randomized study investigated the effects of pioglitazone on cardiometabolic profiles and CV safety in T2DM patients undergoing elective percutaneous coronary intervention (PCI) using bare-metal stents or first-generation drug-eluting stents. A total of 94 eligible patients were randomly assigned to either a pioglitazone or conventional (control) group, and pioglitazone was started the day before PCI. Cardiometabolic profiles were evaluated before PCI and at primary follow-up coronary angiography (5-8 months). Pioglitazone treatment reduced HbA1c levels to a similar degree as conventional treatment (pioglitazone group 6.5 to 6.0%, P < 0.01; control group 6.5 to 5.9%, P < 0.001), without body weight gain. Levels of high-molecular weight adiponectin increased more in the pioglitazone group than the control group (P < 0.001), and the changes were irrespective of baseline glycemic control. Furthermore, pioglitazone significantly reduced plasma levels of natriuretic peptides and preserved cardiac systolic and diastolic function (assessed by echocardiography) without incident hospitalization for worsening HF. The incidence of clinical adverse events was also comparable between the groups. These results indicate that pioglitazone treatment before and after elective PCI may be tolerable and clinically safe and may improve cardiometabolic profiles in T2DM patients.

DPP-4 Inhibitor and Estrogen Share Similar Efficacy Against Cardiac Ischemic-Reperfusion Injury in Obese-Insulin Resistant and Estrogen-Deprived Female Rats

Estrogen deprivation aggravates cardiac injury after myocardial ischemia and reperfusion (I/R) injury. Although either estrogen or the dipeptidyl peptidase-4 (DPP-4) inhibitor, vildagliptin, reduces myocardial damage following cardiac I/R, their effects on the heart in obese-insulin resistant and estrogen deprived conditions remain unknown. Ovariectomized (O) rats (n = 36) were divided to receive either normal diet (NDO) or high-fat diet (HFO) for 12 weeks, followed by treatment with a vehicle, estrogen or vildagliptin for 4 weeks. The setting of in vivo cardiac I/R injury, 30-min ischemia and 120-min reperfusion, was performed. At 12 weeks after ovariectomy, both NDO and HFO rats exhibited an obese-insulin resistant condition. Both NDO and HFO rats treated with estrogen and vildagliptin showed reduced fasting plasma glucose, insulin and HOMA index. Both treatments improved cardiac function indicated by restoration of heart rate variability and increased %left ventricular ejection fraction (%LVEF). The treatments similarly protected cardiac mitochondrial function against I/R injury, leading to a reduction in the infarct size, oxidative stress and apoptosis in the ischemic myocardium. These findings demonstrate that vildagliptin effectively improves metabolic status, and shares similar efficacy to estrogen in reducing myocardial infarction and protecting cardiac mitochondrial function against I/R injury in estrogen-deprived obese-insulin resistant rats.

Troponin I elevation and all-cause mortality after elective percutaneous coronary interventions

BACKGROUND/PURPOSE

Although troponin I (TnI) elevation and myocardial injury after percutaneous coronary interventions (PCI) are frequent findings, their prognoses remain controversial. We aimed to determine the association between any or ≥5 times TnI elevation after elective PCI and subsequent one year mortality rates and long term survival.

METHODS

Consecutive patients admitted for elective PCI between January 2013 and December 2014 were retrospectively analyzed by chart review in two hospitals in Rio de Janeiro. Only patients with post-PCI TnI measurements were included. Clinical, angiographic and procedural characteristics were correlated with any or ≥5 times TnI elevation, as well as 1year mortality and long term survival.

RESULTS

A total of 407 interventions were included in the analysis. Post-PCI TnI elevation was observed in 74.7% of cases and ≥5 times elevations occurred in 41.3%. Age≥70years, female gender and multistenting were predictors of enzyme elevation. Prior aspirin or hypoglycemic therapy were protective factors. One year mortality was significantly associated with any TnI elevation (6.6% vs 1.05%, p=0.035) and values ≥5 times above the normal limit predicted the highest mortality rates (8.13% vs 3.14%, p=0.031). Survival of patients with single vessel disease was also adversely affected by ≥5 times enzyme elevation (log-rank: p=0.039).

CONCLUSION

Troponin I elevation after elective PCI is frequent and associated with progressively higher mortality rates at 1year. A cutoff value ≥5 times the 99th percentile, currently defined as myocardial injury, appears to be an even more significant predictor of this outcome, even in lower risk subgroups.

Factors Associated with High-sensitivity Cardiac Troponin T in Patients with Type 2 Diabetes Mellitus

BACKGROUND

The blood concentration of high-sensitivity cardiac troponin T (hs-cTnT) is an established, useful biomarker for evaluating the pathogenesis of heart failure and predicting cardiovascular events. The aim of this study was to evaluate factors that are potentially associated with elevated blood hs-cTnT in patients with type 2 diabetes mellitus.

PATIENTS AND METHODS

Patients with type 2 diabetes mellitus (N=280, 111 men and 169 women; mean ± SD age: 71±9 years) with no history of cardiovascular events were enrolled. Relationships between hs-cTnT level and various clinical parameters were examined.

RESULTS

Hs-cTnT was detected in 244 (87.1%) patients. There were no significant relationships between hs-cTnT and fasting blood glucose levels or insulin resistance. hs-cTnT was significantly correlated with advanced glycation end-product levels at the skin (r=0.23, p<0.001), blood concentrations of brain natriuretic peptide (r=0.23, p<0.001), reactive oxygen metabolites as markers of oxidative stress (r=0.28, p<0.001), and the augmentation index at the radial artery as marker of arterial reflection (r=0.31, p<0.001). Furthermore, multiple regression analysis revealed that these factors were also selected as independent variables, with hs-cTnT as a subordinate factor.

CONCLUSION

These results indicate that novel cardiovascular risk factors including advanced glycation end-products, in vivo oxidative stress, and high arterial reflection are closely associated with high concentrations of blood hs-cTnT in patients with type 2 diabetes mellitus.

Effects of daily glucose fluctuations on the healing response to everolimus-eluting stent implantation as assessed using continuous glucose monitoring and optical coherence tomography

Background

Several studies have revealed that glucose fluctuations provoke oxidative stress that leads to endothelial cell dysfunction, progression of coronary atherosclerosis, and plaque vulnerability. However, little is known regarding their effect on neointimal growth after stenting in patients with coronary artery disease (CAD). We aimed to investigate the effects of glucose fluctuations on neointimal growth after everolimus-eluting stent (EES) implantation.

Methods

This study examined 50 patients who underwent a 9-month follow-up using optical coherence tomography (OCT) after EES implantation. Glucose fluctuation was expressed as the mean amplitude of glycemic excursion (MAGE), and was determined via continuous glucose monitoring before stenting. At the OCT follow-up, we evaluated the percentage of uncovered struts and three-dimensional uniformity of neointimal distribution by calculating the mean neointimal thickness (NIT) within 360 equally-spaced radial sectors for every 1-mm cross-sectional OCT analysis, and assessed the incidence of major adverse cardiovascular events (MACE).

Results

We evaluated 60 lesions in 50 patients. Linear mixed effect models were used to explore the influence of different variables on variability in NIT and the percentage of uncovered struts and to adjust for covariates. Univariate analysis showed that MAGE was most strongly correlated with the previously mentioned OCT measurements (coefficient β ± standard error = 0.267 ± 0.073 and 0.016 ± 0.003, t = 3.668 and 6.092, both P < 0.001, respectively). In multivariate analysis, MAGE had the strongest effect on variability in NIT (coefficient β ± standard error = 0.239 ± 0.093, P = 0.014) and the percentage of uncovered struts (coefficient β ± standard error = 0.019 ± 0.004, P < 0.001). Five lesions in four patients required target lesion revascularization (10.0 %) at a mean duration of 9 months after EES implantation. Compared to non-MACE cases, cases of MACE exhibited a significantly higher MAGE (99 vs. 68; P = 0.004), maximum NIT (580 vs. 330 µm; P = 0.002), and variability in NIT (100 vs. 65; P = 0.007), although there was no significant difference in these groups’ HbA1c levels.

Conclusions

Glucose fluctuation may affect vessel healing after EES implantation in patients with CAD who are receiving lipid-lowering therapy. Therefore, glucose fluctuations may be an important target for secondary prevention after coronary stenting, which is independent of dyslipidemia control.

Triglycerides to high-density lipoprotein-cholesterol ratio, glycemic control and cardiovascular risk in obese patients with type 2 diabetes

PURPOSE OF REVIEW

This article provides an update on the role of the triglyceride to high-density lipoprotein-cholesterol (triglyceride/HDL-C) ratio in the setting of obesity-related insulin resistance and type 2 diabetes mellitus.

RECENT FINDINGS

Insulin resistance and type 2 diabetes mellitus are well-established risk factors for cardiovascular diseases, and are commonly associated with metabolic abnormalities such as hypertriglyceridemia, low HDL-C and presence of small, dense low-dense lipoprotein (LDL) particles. Mounting evidence suggests that the triglyceride/HDL-C ratio is a marker of insulin resistance, although this relationship might vary as a function of ethnicity and sex. The triglyceride/HDL-C ratio has also been shown to correlate with other atherogenic lipid measurements, such as triglyceride-rich lipoproteins, remnant cholesterol and small dense LDL particles. Recent epidemiologic studies have shown that the triglyceride/HDL-C ratio associates with cardiovascular risk, mainly because of its association with insulin resistance. Finally, triglyceride/HDL-C can also be a marker of glycemic control, especially in obese patients with type 2 diabetes mellitus.

SUMMARY

The triglyceride/HDL-C integrates information on triglyceride-rich lipoproteins, insulin resistance and glycemic control. Future studies may better define its specific clinical role.

Role of oxidative stress in endothelial insulin resistance

The International Diabetes Federation estimates that 316 million people are currently affected by impaired glucose tolerance (IGT). Most importantly, recent forecasts anticipate a dramatic IGT increase with more that 470 million people affected by the year 2035. Impaired insulin sensitivity is major feature of obesity and diabetes and is strongly linked with adverse cardiometabolic phenotypes. However, the etiologic pathway linking impaired glucose tolerance and cardiovascular disease remains to be deciphered. Although insulin resistance has been attributed to inflammatory programs starting in adipose tissue, emerging evidence indicates that endothelial dysfunction may represent the upstream event preceding peripheral impairment of insulin sensitivity. Indeed, suppression of reactive oxygen species-dependent pathways in the endothelium has shown to restore insulin delivery to peripheral organs by preserving nitric oxide (NO) availability. Here we describe emerging theories concerning endothelial insulin resistance, with particular emphasis on the role oxidative stress. Complex molecular circuits including endothelial nitric oxide synthase, prostacyclin synthase, mitochondrial adaptor p66^Shc, nicotinamide adenine dinucleotide phosphate-oxidase oxidase and nuclear factor kappa-B are discussed. Moreover, the review provides insights on the effectiveness of available compounds (i.e., ruboxistaurin, sildenafil, endothelin receptor antagonists, NO donors) in restoring endothelial insulin signalling. Taken together, these aspects may significantly contribute to design novel therapeutic approaches to restore glucose homeostasis in patients with obesity and diabetes.

Insulin resistance, diabetes, and cardiovascular risk

Obesity and type 2 diabetes mellitus (T2DM) are major drivers of cardiovascular disease (CVD). The link between environmental factors, obesity, and dysglycemia indicates that progression to diabetes with time occurs along a "continuum", not necessarily linear, which involves different cellular mechanisms including alterations of insulin signaling, changes in glucose transport, pancreatic beta cell dysfunction, as well as the deregulation of key genes involved in oxidative stress and inflammation. The present review critically addresses key pathophysiological aspects including (i) hyperglycemia and insulin resistance as predictors of CV outcome, (ii) molecular mechanisms underpinning the progression of diabetic vascular complications despite intensive glycemic control, and (iii) stratification of CV risk, with particular emphasis on emerging biomarkers. Taken together, these important aspects may contribute to the development of promising diagnostic approaches as well as mechanism-based therapeutic strategies to reduce CVD burden in obese and diabetic subjects.

Factors affecting high-sensitivity cardiac troponin T elevation in Japanese metabolic syndrome patients

PURPOSE

The blood concentration of cardiac troponin T (ie, high-sensitivity cardiac troponin T [hs-cTnT]), measured using a highly sensitive assay, represents a useful biomarker for evaluating the pathogenesis of heart failure or predicting cardiovascular events. However, little is known about the clinical significance of hs-cTnT in metabolic syndrome. The aim of this study was to examine the factors affecting hs-cTnT elevation in Japanese metabolic syndrome patients.

PATIENTS AND METHODS

We enrolled 258 metabolic syndrome patients who were middle-aged males without a history of cardiovascular events. We examined relationships between hs-cTnT and various clinical parameters, including diagnostic parameters of metabolic syndrome.

RESULTS

There were no significant correlations between hs-cTnT and diagnostic parameters of metabolic syndrome. However, hs-cTnT was significantly correlated with age (P<0.01), blood concentrations of brain natriuretic peptide (P<0.01), reactive oxygen metabolites (markers of oxidative stress, P<0.001), and the cardio-ankle vascular index (marker of arterial function, P<0.01). Furthermore, multiple regression analysis revealed that these factors were independent variables for hs-cTnT as a subordinate factor.

CONCLUSION

The findings of this study indicate that in vivo oxidative stress and abnormality of arterial function are closely associated with an increase in hs-cTnT concentrations in Japanese metabolic syndrome patients.

Acute insulin resistance in ST-segment elevation myocardial infarction in non-diabetic patients is associated with incomplete myocardial reperfusion and impaired coronary microcirculatory function

Background

Insulin resistance (IR) assessed by the Homeostatic Model Assessment (HOMA) index in the acute phase of myocardial infarction in non-diabetic patients was recently established as an independent predictor of intrahospital mortality. In this study we postulated that acute IR is a dynamic phenomenon associated with the development of myocardial and microvascular injury and larger final infarct size in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (pPCI).

Methods

In 104 consecutive patients with the first anterior STEMI without diabetes, the HOMA index was determined on the 2^nd and 7^th day after pPCI. Worst-lead residual ST-segment elevation (ST-E) on postprocedural ECG, coronary flow reserve (CFR) determined by transthoracic Doppler echocardiography on the 2^nd day after pPCI and fixed perfusion defect on single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) determined six weeks after pPCI were analyzed according to HOMA indices.

Results

IR was present in 55 % and 58 % of patients on day 2 and day 7, respectively. Incomplete post-procedural ST-E resolution was more frequent in patients with IR compared to patients without IR, both on day 2 (p = 0.001) and day 7 (p < 0.001). The HOMA index on day 7 correlated with SPECT-MPI perfusion defect (r = 0.331), whereas both HOMA indices correlated well with CFR (r = -0.331 to -0.386) (p < 0.01 for all). In multivariable backward logistic regression analysis adjusted for significant univariate predictors and potential confounding variables, IR on day 2 was an independent predictor of residual ST-E ≥ 2 mm (OR 11.70, 95% CI 2.46-55.51, p = 0.002) and CFR < 2 (OR = 5.98, 95% CI 1.88-19.03, p = 0.002), whereas IR on day 7 was an independent predictor of SPECT-MPI perfusion defect > 20% (OR 11.37, 95% CI 1.34-96.21, p = 0.026).

Conclusion

IR assessed by the HOMA index during the acute phase of the first anterior STEMI in patients without diabetes treated by pPCI is independently associated with poorer myocardial reperfusion, impaired coronary microcirculatory function and potentially with larger final infarct size.

Insulin resistance is associated with coronary plaque vulnerability: insight from optical coherence tomography analysis

AIMS

Previous studies have reported that insulin resistance plays an important role in the progression of atherosclerosis. However, the relationship between insulin resistance and coronary plaque instability is not well established. The purpose of this study was to assess the relationship between insulin resistance and coronary plaque characteristics identified by optical coherence tomography (OCT).

METHODS AND RESULTS

This study enrolled 155 consecutive patients undergoing percutaneous coronary intervention. OCT image acquisitions were performed in the culprit lesions. Insulin resistance was identified using the homeostasis model assessment of insulin resistance (HOMA-IR). Subjects were divided into three tertiles according to the HOMA-IR values. Patients in the higher HOMA tertile had more frequent prevalence of lipid-rich plaques than those in the middle and lower tertiles (83 vs. 62 vs. 57%; P = 0.01). The thin-cap fibroatheroma (TCFA) prevalence rates among the higher (>2.5), middle (1.4-2.5), and lower HOMA-IR (<1.4) tertiles were 50, 29, and 26% (P = 0.02). The microvessel prevalence rates of the three tertiles were 54, 39, and 28% (P = 0.02). Furthermore, in the higher HOMA-IR group, the fibrous cap was significantly thinner compared with the other two tertiles (vs. lower HOMA-IR, P = 0.009; vs. middle HOMA-IR, P = 0.008). On multivariate analysis, acute coronary syndrome [odds ratio (OR): 17.98; 95% confidence interval (CI): 7.12-52.02; P < 0.0001] and HOMA-IR >2.50 (OR: 3.57; 95% CI: 1.42-9.55; P = 0.007) were independent predictors for the presence of TCFA.

CONCLUSION

This study suggests that insulin resistance might be associated with coronary plaque vulnerability.