Insulin resistance influences the impact of hypertension on left ventricular diastolic dysfunction in a community sample

Association of cardiometabolic and triglyceride-glucose index with left ventricular diastolic function in asymptomatic individuals

BACKGROUND AND AIMS

Obesity and insulin resistance are associated with left ventricular diastolic dysfunction (LVDD) and increased risk of heart failure. Cardiometabolic index (CMI) and triglyceride glucose (TyG) are new indexes to assess visceral obesity and insulin resistance, respectively. The study aimed to investigate the clinical usefulness of these indexes for identifying LVDD individuals.

METHODS AND RESULTS

Overall, 1898 asymptomatic individuals were included in this cross-sectional study. Participants underwent anthropometrics, serum biochemical evaluation, and echocardiography. Multiple linear regression analysis revealed that both indexes were independent determinants of diastolic parameters among females; while for males, CMI and TyG were not associated with A velocity. In the multivariate logistic analysis, the proportion of LVDD in the third and fourth quartiles of CMI remained significantly greater than that in the lowest quartile in females (Q3 vs. Q1: odds ratio (OR) = 2.032, 95% confidence interval (CI): 1.181-3.496; Q4 vs. Q1: OR = 2.393, 95% CI: 1.347-4.249); while in males, the incidence of LVDD was significantly greater only in the fourth quartile. For TyG, the presence of LVDD in the fourth quartile was significantly greater in both genders. The discriminant values between the CMI (AUC: 0.704, 95% CI: 0.668-0.739) and TyG (AUC: 0.717, 95% CI: 0.682-0.752) were similar in females. Both indexes performed better in females than in males to identify LVDD.

CONCLUSION

The CMI and TyG might both serve as effective tools to identify LVDD in routine health check-ups in primary care, mainly in females. With simpler parameters, the CMI could be utilized in medically resource-limited areas.

RBP4-based Multimarker Score: A Prognostic Tool for Adverse Cardiovascular Events in Acute Coronary Syndrome Patients

CONTEXT

Retinol binding protein 4 (RBP4) has been implicated in the progression of cardiovascular diseases. However, its association with major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS) remains obscure.

OBJECTIVE

Here, we examined the prognostic value of baseline RBP4 and its derived multimarker score for MACEs in ACS patients.

METHODS

A total of 826 patients with ACS were consecutively recruited from the department of cardiology and prospectively followed up for a median of 1.95 years (interquartile range, 1.02-3.25 years). Plasma RBP4 was measured using enzyme-linked immunosorbent assay. Adjusted associations between RBP4 and its derived multimarker score (1 point was assigned when RBP4 ≥ 38.18μg/mL, left ventricular ejection fraction [LVEF] ≤ 55%, N-terminal pro-B-type natriuretic peptide [NT-proBNP] ≥ 450 ng/L, estimated glomerular filtration rate [eGFR] ≤ 90 mL/min/1.73 m2, and age ≥60) with MACEs were analyzed.

RESULTS

In total, 269 ACS patients (32.57%) experienced MACEs. When patients were grouped by multimarker score (0-1, n = 315; 2-3, n = 406; 4-5, n = 105), there was a significant graded association between RBP4-based multimarker score and risk of MACEs (intermediate score (2-3): HRadj: 1.80; 95% CI, 1.34-2.41; high score (4-5): HRadj: 3.26; 95% CI, 2.21-4.81) and its components (P < .05 for each). Moreover, the prognostic and discriminative value of the RBP4-derived multimarker score remained robust in ACS patients with various high-risk anatomical or clinical characteristics.

CONCLUSION

The RBP4-derived 5-item score serves as a useful risk stratification and decision support for secondary prevention in patients with ACS.

INSR and ISR‑1 gene polymorphisms and the susceptibility of essential hypertension: A meta‑analysis

INSR and ISR-1 may be candidate genes for essential hypertension (EH). However, the genetic association between the INSR and ISR-1 gene polymorphisms and EH risk remains contradictory. To determine a more precise association of the INSR and ISR-1 gene polymorphisms and EH, the present study performed a meta-analysis. Eligible studies up to Jan 2021 were retrieved from multiple databases including PubMed, Embase, Web of Science and China National Knowledge Infrastructure. The pooled odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the genetic associations between the allele, dominant and recessive models of INSR Nsil, RsaI and ISR-1 G972R polymorphisms and EH susceptibility. A total of 10 case-control studies encompassing 2,782 subjects including 1,289 cases and 1,493 controls were evaluated for the present meta-analysis. Neither of the allele, dominant and recessive models of INSR Nsil and ISR-1 G972R polymorphisms was associated with EH risk (P>0.05). While the allele [P=0.0008, OR=0.58, (95% CI)=(0.42, 0.80)], dominant [P=0.02, OR=0.59, (95% CI)=(0.38, 0.92)] and recessive models [P=0.003, OR=0.38, (95% CI)=(0.20, 0.72)] of INSR Rsal polymorphism were associated with decreased risk of EH. Subgroup analysis according to ethnicity showed that the significant associations between the allele, dominant and recessive models of INSR Rsal polymorphism and EH risk were observed in Caucasian populations, but not in Asian populations (P>0.05). In conclusion, the INSR Rsal polymorphism is probably a protective factor for EH. To identify the result, additional case-control designed research with larger numbers of subjects are required.

A Non-Linear Association of Triglyceride Glycemic Index With Cardiovascular and All-Cause Mortality Among Patients With Hypertension

Background

To investigate the association between insulin resistance (IR), quantified by triglyceride glycemic index (TyG index), cardiovascular mortality (CVM), and all-cause mortality (ACM) in hypertension patients.

Methods

We included 8,554 patients with hypertension aged ≥18 years old from the 1999–2014 National Health and Nutrition Examination Surveys (NHANES). The status of CVM and ACM of participants were followed through December 31, 2015. Cox proportional hazards models and Kaplan-Meier survival curves were used to evaluate the relationship between TyG index, CVM, and ACM.

Results

During a median of 82 months follow-up, 1,882 mortality cases had occurred, 434 of which were due to cardiovascular disease. The patients with hypertension with TyG ≥ 10 were older, had a higher chance of being smokers, were obese, had higher blood pressure, and had risk or had cardiovascular disease. In Cox proportional hazards models, compared with the patients with TyG <8, those with TyG ≥ 10 had 56% increased risk for ACM. On the other hand, no significant difference for CVM between the four groups were observed. In the restricted cubic spline regression models, the relationship between TyG index and ACM was non-linear. Subgroup analysis showed non-linear relationship between TyG index and ACM in elderly patients aged ≥60 years. The cut-off value of TyG for ACM was 9.45, and those with higher or lower than 9.45 had more risk of ACM. When TyG index was more than 9.52, the risk for CVM would increase among the whole group. Kaplan-Meier survival curves showed patients with TyG ≥ 10 had higher risk of ACM and CVM (Log rank P < 0.05).

Conclusions

We demonstrated that the association between ACM and TyG index in elderly patients with hypertension aged ≥60 years was non-linear. However, TyG index was only more than 9.52, hence, the risk for CVM would increase among the whole hypertension group.

The role of metabolic syndrome in sudden cardiac death risk: Recent evidence and future directions

Metabolic syndrome (MetS) is a frequent condition whose deleterious effects on the cardiovascular system are often underestimated. MetS is nowadays considered a real pandemic with an estimated prevalence of 25% in general population. Individuals with MetS are at high risk of sudden cardiac death (SCD) as this condition accounts for 50% of all cardiac deaths in such a population. Of interest, recent studies demonstrated that individuals with MetS show 70% increased risk of SCD even without previous history of coronary heart disease (CHD). However, little is known about the interplay between the two conditions. MetS is a complex disease determined by genetic predisposition, unhealthy lifestyle and ageing with deleterious effects on different organs. MetS components trigger a systemic chronic low-grade pro-inflammatory state, associated with excess of sympathetic activity, cardiac hypertrophy, arrhythmias and atherosclerosis. Thus, MetS has an important burden on the cardiovascular system as demonstrated by both preclinical and clinical evidence. The aim of this review is to summarize recent evidence concerning the association between MetS and SCD, showing possible common aetiological processes, and to indicate prospective for future studies and therapeutic targets.

Relation of cardiac function to insulin resistance as evaluated by hyperinsulinemic-euglycemic clamp analysis in individuals with type 2 diabetes

AIMS

Whereas homeostasis model assessment of insulin resistance (HOMA-IR), an easily measured but limited index of insulin resistance, has been shown to correlate with impairment of cardiac function in individuals without diabetes, the pathological relevance of insulin resistance to the development of cardiac dysfunction in individuals with type 2 diabetes has remained unclear. Here we investigated the relation between left ventricular (LV) function as assessed by echocardiography and insulin resistance as evaluated by hyperinsulinemic-euglycemic clamp analysis, the gold standard for measurement of this parameter, in individuals with type 2 diabetes.

METHODS

This retrospective study included 34 individuals with type 2 diabetes who underwent both hyperinsulinemic-euglycemic clamp analysis and echocardiography. Both the insulin sensitivity index (ISI) as determined by glucose clamp analysis as well as HOMA-IR were determined as measures of insulin resistance. The ratio of the peak early- to late-diastolic mitral inflow velocities (E/A) and the LV ejection fraction (LVEF) were determined as measures of diastolic and systolic function, respectively.

RESULTS

The ISI was significantly correlated with both the E/A ratio and LVEF (correlation coefficients of 0.480 and 0.360, respectively), whereas HOMA-IR was not correlated with either cardiac parameter. Multivariate analysis revealed that ISI was an independent predictor for both a high log [E/A] (P = 0.031) and a high LVEF (P = 0.045).

CONCLUSIONS

Insulin resistance as evaluated by hyperinsulinemic-euglycemic clamp analysis may be causally related to LV diastolic and systolic dysfunction in individuals with type 2 diabetes.

Subclinical decrease in cardiac autonomic and diastolic function in patients with metabolic disorders: HSCAA study

Heart failure due to decreased diastolic function, HFpEF, is a growing health concern with rising prevalence. We examined subclinical cardiac autonomic and diastolic functions in 605 patients with metabolic diseases classified as pre-heart failure. Presence of glucose intolerance or diabetes, or visceral adiposity was significantly associated with reduced cardiac autonomic and diastolic functions. Higher autonomic functions were significantly associated with a parameter of better cardiac diastolic function (E/A) (SDNN: r = 0.306, p < 0.01; HF: r = 0.341, p < 0.01), with the association independent of diabetes, body mass index, visceral adiposity and insulin resistance index. Thus, reduced autonomic function may be a potential predictor for decreased cardiac diastolic functions in metabolic disorders.

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Metabolic disorders, including diabetes and obesity, are known risk factors for HFpEF.

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Reduced autonomic function may be involved in pathogenesis of HFpEF.

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Cardiac diastolic function in metabolic disorders in pre-HF phase is not well examined.

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In pre-HF subjects, reduced autonomic function is associated with lower cardiac diastolic functions.

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Our findings provide new insights into HFpEF etiology in metabolic disorders.

Insulin Resistance in Healthy U.S. Adults: Findings from the National Health and Nutrition Examination Survey (NHANES)

BACKGROUND

Insulin is fundamental in two conditions that are epidemic in the United States and globally: obesity and type II diabetes. Given insulin's established mechanistic involvement in energy balance and glucose tolerance, we examined its relationship to common health-related endpoints in a large population-based sample.

METHODS

The National Health and Nutrition Examination Survey is a cross-sectional study that uses a complex multistage probability design to obtain a representative sample of the United States population. Adult participants were included from 8 successive 2-year data waves (1999-2014), including 9,224 normal individuals, 7,699 prediabetic, and 3,413 diabetic subjects. The homeostatic model for insulin resistance (HOMA-IR) was available for 20,336 participants and its relationship with demographic, anthropometric, and clinical data was analyzed. We examined the relationship of HOMA-IR to 8 groups of outcome variables: general health, anthropometric/metabolic [waist size, body mass index (BMI)], cardiovascular (blood pressure), lipid [triglycerides, high-density lipoprotein (HDL)], hepatic [alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT)], hematologic [white blood cells (WBC), hemoglobin (Hgb), platelets], inflammatory (C-reactive protein), and nutritional (vitamins D and C, serum folate, and pyridoxine) variables.

RESULTS

HOMA-IR was generally strongly, monotonically, and highly significantly associated with adjusted outcomes in normal subjects, although clinical laboratory values were generally within normal bounds across insulin quartiles. In the normal subset, the odds ratio and 95% confidence interval for a quartile change in HOMA-IR for obesity (BMI > 30) was 3.62 (3.30-3.97), and for the highest quintile for the triglyceride/HDL the ratio was 2.00 (1.77-2.26), for GGT it was 1.40 (1.24-1.58), and for WBC it was 1.28 (1.16-1.40). The relationship of HOMA-IR to the various outcomes was broadly similar to that observed in prediabetics and diabetics with a few exceptions.

CONCLUSIONS

HOMA-IR levels in a large sample of normal individuals are associated with poorer general health and adverse changes across a wide range of markers. A similar pattern of alterations is observed in prediabetic and diabetic samples.

IMPACT

Clinically, checking insulin levels may be helpful to identify patients that merit further observation and are candidates for early interventions.

Left Ventricular Diastolic Dysfunction in Type 2 Diabetes-Progress and Perspectives

In-depth understanding of early cardiovascular manifestations in diabetes is high on international research and prevention agendas given that cardiovascular events are the leading cause of death for diabetic patients. Our aim was to review recent developments in the echocardiographic assessment of left ventricular diastolic dysfunction (LVDD) as a telltale pre-clinical disturbance preceding diabetic cardiomyopathy. We analyzed papers in which patients had been comprehensively assessed echocardiographically according to the latest LVDD guidelines (2016), and those affording comparisons with previous, widely used recommendations (2009). We found that the updated algorithm for LVDD is more effective in predicting adverse cardiovascular events in patients with established LVDD, and less specific in grading other patients (labelled "indeterminate"). This may prove instrumental for recruiting "indeterminate" LVDD cases among patients with type 2 diabetes mellitus (T2DM) in future screening programs. As an interesting consideration, the elevated values of the index E/e' can point to early diastolic impairment, foretelling diabetic cardiomyopathy. Identifying subclinical signs early makes clinical sense, but the complex nature of T2DM calls for further research. Specifically, longitudinal studies on rigorously selected cohorts of diabetic patients are needed to better understand and predict the subtle, slow onset of cardiac manifestations with T2DM as a complicating backdrop.

Insulin resistance influences the impact of hypertension on left ventricular diastolic dysfunction in a community sample

Background

Although obesity‐associated metabolic abnormalities (insulin resistance‐IR) may not play as marked a role in determining left ventricular (LV) diastolic dysfunction (DD) as hypertension, the impact of combinations of these risk factors on DD is unknown.

Hypothesis

We hypothesized that IR influences the impact of hypertension on DD.

Methods

In 704 randomly selected participants from a community sample with a high prevalence of hypertension (50.6%) and obesity (46.5%), we determined adiposity indices, IR from the homeostasis model (HOMA‐IR) and LV diastolic function using standard echocardiographic techniques.

Results

HOMA‐IR was independently associated with lateral wall e' and E/e' (P < 0.05 to P < 0.005) as well as a diagnosis of DD (P < 0.02). Importantly, however, an enhanced relationship between HOMA‐IR and E/e' in hypertensives (n = 356, partial r = 0.15, P < 0.005) as compared to normotensives (n = 348, partial r = 0.02 P = 0.75) was noted. Consequently, as compared to normotensives, with adjustments for confounders, hypertension was independently associated with DD only in those with the highest tertile of HOMA‐IR (odds ratio = 2.65, 95% confidence interval = 1.29‐5.42, P < 0.01), while in those with the lowest tertile of HOMA‐IR, hypertension failed to show a higher prevalence of DD (P = 0.22).

Conclusions

Insulin resistance enhances the impact of hypertension on LV DD. Thus, DD is more likely to occur with the combination of hypertension and IR.