Homeostasis model assessment of insulin resistance and the risk of cardiovascular events in middle-aged non-diabetic Japanese men

Trends in HOMA-IR values among South Korean adolescents from 2007-2010 to 2019-2020: a sex-, age-, and weight status-specific analysis

BACKGROUND/OBJECTIVES

An increase in obesity prevalence may lead to an increase in the HOMA-IR value. This study aimed to investigate changes in age- and sex-specific homeostasis model assessment of insulin resistance (HOMA-IR) values among South Korean adolescents, using data from the Korean National Health and Nutrition Examination Survey (KNHANES) IV, V, and VIII conducted between 2007-2010 and 2019-2020.

SUBJECTS/METHODS

Overall, 4621 adolescents aged 10-18 years were evaluated, including 3473 from the 2007-2010 dataset and 1148 from the 2019-2020 dataset. The mean HOMA-IR values and percentile curves were evaluated by age, sex, and weight status.

RESULTS

The mean HOMA-IR values peaked at puberty in both sexes and further increased during puberty in the 2019-2020 dataset (boys 5.21, 95% confidence interval [CI] 4.16-6.26; girls 5.21, 95% CI 3.09-7.33) compared with the 2007-2010 dataset (boys 3.25, 95% CI 3.04-3.47; girls 3.58, 95% CI 3.31-3.85). Both groups (with normal-weight and overweight/obesity) exhibited a peak HOMA-IR value during puberty in both sexes and both datasets, although the group with overweight/obesity had a higher and wider peak age range. While the mean HOMA-IR values did not change in adolescents with normal-weight, they increased during puberty and post-puberty in boys with overweight/obesity.

CONCLUSIONS

HOMA-IR values should be interpreted considering sex, weight status, and pubertal stages. In particular, during the pubertal period, insulin resistance (IR) can coexist not only due to weight-related factors but also as a result of the distinct hormonal changes characteristic of puberty. Over the 10-year period, the mean HOMA-IR values increased in the group with overweight/obesity during puberty and post-puberty, highlighting the need for active intervention to prevent metabolic complications in adolescents with overweight/obesity.

Metabolic Score for Insulin Resistance (METS-IR) Predicts Adverse Cardiovascular Events in Patients with Type 2 Diabetes and Ischemic Cardiomyopathy

Purpose

This study aimed to evaluate the association between metabolic score for insulin resistance (METS-IR) and adverse cardiovascular events in patients with ischemic cardiomyopathy (ICM) and type 2 diabetes mellitus (T2DM).

Methods

METS-IR was calculated using the following formula: ln[(2 × fasting plasma glucose (mg/dL) + fasting triglyceride (mg/dL)] × body mass index (kg/m2)/(ln[high-density lipoprotein cholesterol (mg/dL)]). Major adverse cardiovascular events (MACEs) were defined as the composite outcome of nonfatal myocardial infarction, cardiac death, and rehospitalization for heart failure. Cox proportional hazards regression analysis was used to evaluate the association between METS-IR and adverse outcomes. The predictive value of METS-IR was evaluated by the area under the curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Results

The incidence of MACEs increased with METS-IR tertiles at a 3‑year follow‑up. Kaplan‒Meier curves showed a significant difference in event-free survival probability between METS-IR tertiles (P<0.05). Multivariate Cox hazard regression analysis adjusting for multiple confounding factors showed that when comparing the highest and lowest METS-IR tertiles, the hazard ratio was 1.886 (95% CI:1.613-2.204; P<0.001). Adding METS-IR to the established risk model had an incremental effect on the predicted value of MACEs (AUC=0.637, 95% CI:0.605-0.670, P<0.001; NRI=0.191, P<0.001; IDI=0.028, P<0.001).

Conclusion

METS-IR, a simple score of insulin resistance, predicts the occurrence of MACEs in patients with ICM and T2DM, independent of known cardiovascular risk factors. These results suggest that METS-IR may be a useful marker for risk stratification and prognosis in patients with ICM and T2DM.

HOMA-IR as a predictor of Health Outcomes in Patients with Metabolic Risk Factors: A Systematic Review and Meta-analysis

INTRODUCTION

There exists clinical interest in the following question: Is there an association between HOMA-IR and the risk of developing metabolic diseases?

AIMS

Assessing the association between high values of HOMA-IR with the incidence of T2DM, MACE, essential hypertension, dyslipidemia, NASH, and cancer in healthy participants and participants with a component of metabolic syndrome.

METHODS

Databases were searched by an experienced librarian to find eligible studies. Observational cohort studies enrolling healthy adults and adults with metabolic syndrome components that evaluated HOMA as a marker of IR were considered for inclusion. Eligibility assessment, data extraction and risk of bias assessment were performed independently and in duplicate. Baseline characteristics of patients, cutoff values of HOMA-IR to predict metabolic events were extracted independently and in duplicate.

RESULTS

38 studies (215,878 participants) proved eligible. A higher HOMA-IR value had a significant effect on the risk of developing T2DM (HR 1.87; CI 1.40-2.49), presenting non-fatal MACE (HR 1.46; CI 1.08-1.97) and hypertension (HR 1.35; CI 1.15-1.59). No association was found regarding cancer mortality and fatal MACE with higher HOMA-IR values, there was not enough information to carry out a meta-analysis to establish an association between higher values of HOMA with cancer incidence, dyslipidemia, and NASH.

CONCLUSIONS

High values of HOMA were associated with an increased risk of diabetes, hypertension, and non-fatal MACE; yet, not for cardiovascular or cancer mortality. More research is needed to determine the value of the HOMA index in metabolic and cardiovascular outcomes.

PROSPERO REGISTRATION NUMBER

CRD42020187645.

A higher TyG index is related with a higher prevalence of erectile dysfunction in males between the ages 20-70 in the United States, according to a cross-sectional research

Objective

This study aims to investigate the relationship between triglyceride glucose index (TyG) and erectile dysfunction (ED) among United States (US) adult males.

Methods

A logistic regression analysis, subgroup analysis, and the computation of the dose-response curve were used to investigate the relationship between TyG index and ED prevalence among participants from the 2001-2004 National Health and Nutrition Examination Survey (NHANES) database.

Results

After adjusting for all confounders, each unit increase in TyR index was associated with a 25 percent increase in ED prevalence (OR=1.25, 95%CI:1.03, 1.52), and stratified analysis showed that elevated TyG index was associated with increased ED prevalence in the 50-year old group (OR=1.35, 95% CI:1.05, 1.74), the Mexican-American group (OR=1.50, 95% CI:1.00, 2.23) and BMI 25-29.9 kg/m2 (OR=1.48, 95% CI:1.08, 2.01). The dose-response curve demonstrated a positive linear connection between the TyG index and the risk of ED.

Conclusion

It has been shown that a higher TyG index is associated with a higher prevalence of erectile dysfunction. Although the causal relationship is not clear, it still deserves clinical attention.

Association Between Insulin Resistance, Oxidative Stress, Sympathetic Activity and Coronary Microvascular Function in Patients With Early Stage Impaired Glucose Metabolism

BACKGROUND

Although acute hyperglycemia and insulin resistance (IR) are risk factors for atherosclerosis development through oxidative stress and sympathetic activation in diabetes mellitus, the association of these factors with coronary microvascular function in the early diabetic stage remains controversial.

METHODS AND RESULTS

Using transthoracic echocardiography, coronary flow velocity (CFV) and its reserve (CFVR) as parameters of coronary microvascular function were measured before and 1 h after an oral glucose tolerance test (OGTT) in 40 patients (aged 59±12 years) without diagnosed diabetes mellitus or coronary artery disease. Plasma glucose, insulin and thiobarbituric acid reactive substance (TBARS; an oxidative stress marker) were measured during the OGTT. IR was evaluated as homeostasis model assessment of IR (HOMA-R). Sympathetic activity was evaluated by using plasma catecholamines after OGTT. CFVR decreased after an OGTT (P<0.0001) mainly because of an increased baseline CFV (P<0.0001). Although the change in CFVR was not associated with the change in TBARS and catecholamines, it was independently associated with HOMA-R on the multivariate regression analysis (β=-0.40, P=0.01). Another multivariate regression analysis revealed that change in baseline CFV was independently associated with HOMA-R (β=0.35, P=0.03).

CONCLUSIONS

IR, rather than oxidative stress and sympathetic activity, was associated with an increase in baseline CFV and a decline in CFVR during acute hyperglycemia. IR might play an important role in increased myocardial oxygen demand and coronary microvascular dysfunction.

Quantifying the Homeostatic Model Assessment of Insulin Resistance to Predict Mortality in Multi-organ Dysfunction Syndrome

Background

Insulin resistance is an integral component of a multi-organ dysfunction syndrome (MODS) associated with increased mortality. We determined a cutoff value for the homeostatic model assessment of insulin resistance (HOMA-IR) during an ICU admission that could predict 28-day mortality of nondiabetic MODS patients.

Materials and methods

In this prospective, outcome assessor blinded cohort design, we evaluated 82 such patients for fasting blood glucose (FBG)/insulin levels (FIL) during an ICU admission and followed their outcome for 28 days. The primary outcome variable was the HOMA-IR score calculated from the above variables. The statistical tool included receiver operating characteristic curve, Youden index, and correlation and regression analysis.

Results

Overall, 38 patients succumbed to their illness. The optimal cutoff value for HOMA-IR was ≥1.61 (area under curve: 0.684, sensitivity: 36.8%, specificity: 95.5%). The 28-day survival was significantly lower (p = 0.001) at HOMA-IR threshold ≥1.61 (odds ratio: 12.25, hazard ratio: 2.98). The mean HOMA-IR among survivors vs nonsurvivors was 0.76 ± 0.61 and 1.38 ± 1.14, respectively (p = 0.004). Except for FIL and FBG, HOMA-IR values did not correlate with any other baseline or outcome parameters (demographics, APACHE II/sequential organ failure assessment score, vasopressor needs, or ICU/hospital stay). On comparing these parameters across the HOMA-IR threshold, only FIL and the hospital stay varied significantly. Most of the outcome parameters, however, varied significantly among nonsurvivors vs survivors.

Conclusion

The HOMA-IR is a significant predictor of mortality in MODS. Its cutoff value may assist in determining a reference range for critically ill patients. Its routine use in the light of other disease severity scores may serve in their better prognostication.

How to cite this article

Sama S, Jain G, Kant R, Bhadoria AS, Naithani M, Kumar A. Quantifying the Homeostatic Model Assessment of Insulin Resistance to Predict Mortality in Multi-organ Dysfunction Syndrome. Indian J Crit Care Med 2021;25(12):1364–1369.

An Elevated METS-IR Index Is Associated With Higher Asthma Morbidity and Earlier Age of First Asthma in US Adults: Results Based on a Cross-Sectional Study

OBJECTIVE

The purpose of this study was to evaluate whether there is a correlation between the METS-IR index and asthma among Americans.

METHODS

In an attempt to establish the relationship between the METS-IR index and asthma prevalence and age at first onset of asthma, we conducted a logistic regression analysis, subgroup analysis, and dose-response curve analysis using the National Health and Nutrition Examination Survey (NHANES) database.

RESULTS

In model 3, each unit increase in METS-IR index led to 1.5% increase in asthma prevalence (OR= 1.015, 95% CI: 1.012, 1.018) and an earlier age of onset of asthma by 0.057years (β= -0.057, 95% CI: -0.112, -0.002).Stratified analysis determined that an increase in METS-IR index was associated with asthma prevalence in almost all subgroups, except in the group where it was not known whether a blood relative had asthma, and a positive linear relationship was found between METS-IR index and asthma prevalence, as well as a linear negative relationship with age at asthma onset.

CONCLUSION

Despite the fact that a direct causal relationship cannot be demonstrated, a higher METS-IR index is positively related to asthma prevalence and correspondingly may result in asthma onset at younger ages.

Is the METS-IR Index a Potential New Biomarker for Kidney Stone Development?

OBJECTIVE

The purpose of this study was to examine whether the METS-IR index is associated with kidney stones in American adults.

METHOD

Participants from the National Health and Nutrition Examination Survey (NHANES) database from 2007-2018 were selected for logistic regression analysis, subgroup analyses, and the calculation of dose-response curves to assess the association between the METS-IR index and the incidence of kidney stones.

RESULT

This study enrolled 30,612 adults aged >20 years, 2901 of whom self-reported having had kidney stones in the past. And, after controlling for potential confounders, each unit increase in the METS-IR index was linked with a 1.23 percent rise in kidney stone incidence (OR= 1.0123, 95% CI: 1.0092 - 1.0155), with stratified analysis indicating that this was true in all subgroups. Between all groups, an elevated METS-IR index was related to kidney stone formation, and the dose-response curve revealed a positive non-linear connection between METS-IR index and kidney stone risk, with a threshold effect analysis revealing an inflection point value of 50.8314.

CONCLUSION

Higher METS-IR index is associated with the occurrence of kidney stones,and while no causative association can be shown, this is cause for concern.

Insulin resistance and muscle weakness are synergistic risk factors for silent lacunar infarcts: the Bunkyo Health Study

Insulin resistance and muscle weakness are risk factors for silent lacunar infarcts (SLI), but it is unclear whether they are still independent risk factors when adjusted for each other. In addition, the effect of their combination on SLI is completely unknown. We evaluated SLI, insulin sensitivity, and knee extensor muscle strength by magnetic resonance imaging, PREDIM, and dynamometer, respectively, in 1531 elderly people aged 65–84 years living in an urban area of Tokyo. Among the study subjects, 251 (16.4%) had SLI. Impaired insulin sensitivity (High; 1.00 [reference], Medium; 1.53 [95% confidence interval (CI) 0.94–2.48], Low; 1.86 [1.02–3.39], p for trend 0.047) and reduced muscle strength (High; 1.00 [reference], Medium; 1.40 [0.98–2.02], Low; 1.49 [1.04–2.15], p for trend 0.037) were independently associated with increased risk for SLI in the fully adjusted model. In terms of combined, subjects classified as having the lowest insulin sensitivity and lowest strength were 4.33 times (95% CI 1.64–11.45) more likely to have a SLI than those classified as having the highest insulin sensitivity and highest strength. Impaired insulin sensitivity and reduced muscle strength were independently associated with higher risk of SLI in elderly subjects, and their combination synergistically increased this risk.

Disparities in cardio metabolic risk between Black and White women with polycystic ovary syndrome: a systematic review and meta-analysis

OBJECTIVE

We conducted a systematic review and meta-analysis to summarize and quantitatively pool evidence on cardiometabolic health disparities between Black and White women with polycystic ovary syndrome in the United States in response to the call for further delineation of these disparities in the international evidence-based guideline for the assessment and management of polycystic ovary syndrome.

DATA SOURCES

Databases of MEDLINE, Web of Science, and Scopus were searched initially through March 05, 2020, and confirmed on September 11, 2020.

STUDY ELIGIBILITY CRITERIA

Observational studies documenting cardiometabolic risk profile (glucoregulatory, lipid profile, anthropometric, and blood pressure status) in Black and White women with polycystic ovary syndrome were included. Studies on children (<17 years old) and pregnant or menopausal-aged women (>50 years) were excluded. The primary outcome was fasting glucose. Furthermore, data on major cardiovascular events (stroke, coronary heart disease, heart failure) and mortality rate (cardiovascular death, total mortality) were evaluated.

METHODS

Data were pooled by random-effects models and expressed as mean differences and 95% confidence intervals. Studies were weighted based on the inverse of the variance. Heterogeneity was evaluated by Cochran Q and I2 statistics. Study methodologic quality was assessed by the Newcastle-Ottawa scale.

RESULTS

A total of 11 studies (N=2851 [652 Black and 2199 White]) evaluated cardiometabolic risk profile and all had high quality (Newcastle-Ottawa scale score of ≥8). No studies reported on cardiovascular events and mortality rate. Black women had comparable fasting glucose (-0.61 [-1.69 to 2.92] mg/dL; I2=62.5%), yet exhibited increased fasting insulin (6.76 [4.97-8.56] μIU/mL; I2=59.0%); homeostatic model assessment of insulin resistance (1.47 [0.86-2.08]; I2=83.2%); systolic blood pressure (3.32 [0.34-6.30] mm Hg; I2=52.0%); and decreased triglyceride (-32.56 [-54.69 to -10.42] mg/dL; I2=68.0%) compared with White women (all, P≤.03). Groups exhibited comparable total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and diastolic blood pressure (all, P≥.06).

CONCLUSIONS

Black women with polycystic ovary syndrome have a greater tendency for an adverse cardiometabolic risk profile (increased insulin, homeostatic model assessment of insulin resistance, and systolic blood pressure) despite lower triglycerides than White women. Our observations support the consideration of these disparities for diagnostic, monitoring, and management practices in Black women and for future guideline recommendations. Given the heterogeneity among studies, future research should address the relative contributions of biologic, environmental, socioeconomic, and healthcare factors to the observed disparities. Furthermore, longitudinal research is required to address patient-pressing complications, including cardiovascular events and mortality rate in Black women with polycystic ovary syndrome as a high-risk yet understudied population.

Investigating the relationship between insulin resistance and adipose tissue in a randomized Tehrani population

OBJECTIVES

Insulin resistance is the most common metabolic change associated with obesity. The present study aimed to investigate the relationship between insulin resistance and body composition especially adipose tissue in a randomized Tehrani population.

METHODS

This study used data of 2,160 individuals registered in a cross-sectional study on were randomly selected from among subjects who were referred to nutrition counseling clinic in Tehran, from April 2016 to September 2017. Insulin resistance was calculated by homeostasis model assessment formula. The odds ratio (95% CI) was calculated using logistic regression models.

RESULTS

The mean age of the men was 39 (±10) and women were 41 (±11) (the age ranged from 20 to 50 years). The risk of increased HOMA-IR was 1.03 (95% CI: 1.01-1.04) for an increase in one percent of Body fat, and 1.03 (95% CI: 1.00-1.05) for an increase in one percent of Trunk fat. Moreover, the odds ratio of FBS for an increase in one unit of Body fat percent and Trunk fat percent increased by 1.05 (adjusted odds ratio [95% CI: 1.03, 1.06]) and 1.05 (95% CI: 1.02, 1.08). Also, the risk of increased Fasting Insulin was 1.05 (95% CI: 1.03-1.07) for an increase in one unit of Body fat percent, and 1.05 (95% CI: 1.02-1.08) for an increase in one unit of Trunk fat percent.

CONCLUSIONS

The findings of the present study showed that there was a significant relationship between HOMA-IR, Fasting blood sugar, Fasting Insulin, and 2 h Insulin with percent of Body fat, percent of Trunk fat.

Elevated triglyceride-glucose index predicts risk of incident ischaemic stroke: The Rural Chinese cohort study

AIM

As the association between insulin resistance and ischaemic stroke is conflicting, our study aimed to examine the association between triglyceride-glucose (TyG), a surrogate marker of insulin resistance, and incident ischaemic stroke, and also to further assess the potential effect of modification by several known risk factors of stroke.

METHODS

The Rural Chinese Cohort Study enrolled 11,777 participants, aged ≥40 years, who were free of stroke and cardiovascular disease at baseline during 2007-2008, and who were then followed during 2013-2014. TyG was determined using the following formula: Ln[fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. The relative risk (RR) and 95% confidence interval (CI) of incident ischaemic stroke associated with TyG were estimated using modified Poisson regression models.

RESULTS

During a median follow-up duration of 6 years, 677 new ischaemic stroke cases were identified. After multivariate adjustment, RR (95% CI) values for ischaemic stroke were 1.33 (1.01-1.75), 1.57 (1.17-2.10) and 1.95 (1.34-2.82) in TyG quartile (Q) 2, 3 and 4 groups, respectively, compared with Q1. A significant interaction between TyG index and age for risk of ischaemic stroke (P_interaction < 0.001) was also observed. However, no significant interaction was found between TyG index and other potential risk factors of risk for ischaemic stroke, although there were significant positive associations with female, non-smoker, non-drinker, low or moderate physical activity, non-obese and non-type 2 diabetes mellitus groups.

CONCLUSION

Elevated TyG index is an independent predictor of ischaemic stroke in the general population, and insulin resistance may be positively associated with future stroke risk.

Prevalence of metabolic disturbances among women with polycystic ovary syndrome in different regions of Brazil

OBJECTIVE

To describe the prevalence of metabolic disturbances in a large cohort of women with polycystic ovary syndrome (PCOS) in southeastern Brazil and to compare the findings with other cohorts of Brazilian women with PCOS.

METHODS

A retrospective study analyzing clinical and laboratory data of 462 women with PCOS treated at an outpatient clinic in a tertiary hospital in southeastern Brazil. Prevalence of insulin resistance, glucose intolerance, type 2 diabetes, dyslipidemia, central obesity, hypertension, and metabolic syndrome was compared to that of other cohorts of age and body mass index-matched Brazilian women with PCOS.

RESULTS

Women with PCOS had a median age of 25.0 (21.0-29.0) years and BMI of 28.7 (23.9-34.0) kg/m² . Prevalence of insulin resistance, glucose intolerance, and type 2 diabetes varied from 39.6% to 55.0%, 7.2% to 28.1%, and 2.0% to 4.1%, respectively. Prevalence of central obesity, dyslipidemia due to decreased high-density lipoprotein cholesterol, hypertriglyceridemia, and metabolic syndrome ranged from 57.8% to 66.4%, 54.1% to 70.4%, 22.9% to 35.1%, and 27.4% to 38.3%, respectively, which did not differ among regions in Brazil.

CONCLUSION

Prevalence of metabolic disturbances was high among Brazilian women with PCOS. This study suggests that, from a public health perspective, authorities in Brazil should be aware of and encourage screening for metabolic dysfunction in women with PCOS in all regions of the country.

Relation between HOMA-IR and insulin sensitivity index determined by hyperinsulinemic-euglycemic clamp analysis during treatment with a sodium-glucose cotransporter 2 inhibitor

We had aimed to determine whether homeostasis model assessment-insulin resistance (HOMA-IR) reflects insulin resistance-sensitivity during treatment with a sodium-glucose cotransporter 2 inhibitor (SGLT2i). Hyperinsulinemic-euglycemic clamp analysis was performed in 22 patients with type 2 diabetic patients taking dapagliflozin (5 mg/day before or after breakfast). Propensity score matching of these individuals (SGLT2i group) for age, sex, body mass index, and clamp-derived tissue glucose uptake rate with 44 type 2 diabetic patients who had undergone clamp analysis without SGLT2i treatment (control group) identified 17 paired subjects in each group for further analysis of the relation between HOMA-IR and a clamp-derived insulin sensitivity index (ISI). Natural log-transformed HOMA-IR was negatively correlated with ISI in both SGLT2i (r = -0.527, p = 0.030) and control (r = -0.534, p = 0.027) groups. The simple regression lines for log-transformed HOMA-IR and ISI in the two groups showed similar slopes but differed in their intercepts. Multivariate analysis revealed that HOMA-IR for patients with the same ISI in the two groups was related by the formula: HOMA-IR_control = HOMA-IR_SGLT2i × 2.45. In conclusion, HOMA-IR was well correlated with ISI during SGLT2i treatment, but values corresponding to the same ISI were lower in the SGLT2i group than in the control group.

Health status of workers approximately 60 years of age and the risk of early death after compulsory retirement: A cohort study

Objectives

The increasing number of working elderly people has enhanced the importance of workplace health promotion activities. We investigated the association between the health status of workers approximately 60 years of age and the risk of all‐cause mortality after compulsory retirement in Japan.

Methods

The 2026 participants (1299 males and 727 females) had retired from a metal‐products factory at ≥60 years of age. Baseline health examinations were conducted at 60 years of age and included questions about medical history and lifestyle factors; the participants also underwent a physical examination. The participants were followed up annually by mail for an average of 7.4 years. The association between health status at age 60 years and the risk of all‐cause mortality was assessed by Cox proportional hazards regression analysis.

Results

During the study, 71 deaths were reported. The age‐ and sex‐adjusted hazard ratio (HR [95% confidence interval]) for all‐cause mortality was higher for males (HR, 3.41 [1.73‐6.69]) compared with females, participants with a low body mass index (<18.5 kg/m²; HR 3.84 [1.91‐7.73]) compared with normal body weight, smokers (HR, 2.63 [1.51‐4.58]) compared with nonsmokers, and those with three or more of four metabolic abnormalities (obesity, high blood pressure, dyslipidemia, and glucose intolerance) (HR 2.29 [1.04‐5.02]) compared with no metabolic abnormalities. The associations were unaffected by adjustment for these factors.

Conclusion

Maintenance of an appropriate body weight, smoking cessation, and elimination of metabolic syndrome are required for older workers to prevent early death after retirement.

Sex Differences in the Association Between Insulin Resistance and Incident Coronary Heart Disease and Stroke Among Blacks Without Diabetes Mellitus: The Jackson Heart Study

Background

Studies exploring the association between insulin resistance (IR) and cardiovascular disease in blacks have not been conclusive, especially for coronary heart disease (CHD). The McAuley index and homeostasis model assessment of IR (HOMA‐IR) perform differently in predicting cardiovascular disease. We investigated this association in the Jackson Heart Study, a large longitudinal cohort of blacks.

Methods and Results

IR was estimated for 3565 participants without diabetes mellitus and cardiovascular disease at baseline using the McAuley index and HOMA‐IR, and their associations with incident CHD and stroke (composite outcome) were compared. A lower McAuley index and higher HOMA‐IR are indicative of IR. Cox regression analysis was used to estimate adjusted hazard ratios for incident CHD and/or stroke. There were 158 events (89 CHD‐only, 58 stroke‐only, and 11 CHD/stroke) over a median follow‐up of 8.4 years. After adjustment for demographic factors, the risk of the composite outcome decreased with each SD increase in the McAuley index (hazard ratio 0.80; 95% CI: 0.67–0.96), with no attenuation after further accounting for CHD and stroke risk factors. When considered individually, McAuley index and HOMA‐IR were associated with CHD (hazard ratio 0.71, 95% CI: 0.55–0.92 and hazard ratio 1.33, 95% CI: 1.03–1.72, respectively), but not stroke risk. The logHOMA‐IR and CHD association was present in men, but not in women (P_interaction=0.01).

Conclusions

Both HOMA‐IR and the McAuley index demonstrate strong associations with CHD but not stroke risk in blacks. The logHOMA‐IR and CHD association was present in men, but not in women.

Presence of hypertension modifies the impact of insulin resistance on incident cardiovascular disease in a Middle Eastern population: the Tehran Lipid and Glucose Study

AIMS

To examine the independent impacts of the homeostasis model assessment of insulin resistance (HOMA-IR) and the updated model (HOMA2-IR) on incident cardiovascular /coronary heart disease in a Middle Eastern population with a high prevalence of cardiovascular disease risk factors.

METHODS

We examined 3777 Iranian people, aged ≥ 30 years, without history of cardiovascular disease and without use of antidiabetic medication at baseline. Both HOMA-IR and HOMA2-IR were log-transformed and categorized into quartiles. The multivariable Cox proportional hazard regression model, adjusted for traditional cardiovascular disease risk factors, was applied to examine the association between HOMA-IR/HOMA2-IR with incident cardiovascular/coronary heart disease, considering the lowest quartile as reference.

RESULTS

During a median follow-up of > 10 years, 197 cardiovascular disease and 181 coronary heart disease events occurred. Among the covariates, we found a significant interaction between hypertension and HOMA-IR/HOMA2-IR for incident coronary heart/cardiovascular disease (all P ≤ 0.01). Among the population without hypertension, the risk of cardiovascular disease significantly increased in the second [hazard ratio 1.96 (95% CI 1.04-3.68)], third [hazard ratio 1.93 (95% CI 1.00-3.75)] and fourth [hazard ratio 2.34 (95% CI 1.15-4.75)] quartiles of HOMA-IR, and the risk of coronary heart disease increased significantly in the fourth quartile of HOMA-IR [hazard ratio 2.30 (95% CI 1.12-4.73)], but no significant association was detected between HOMA-IR and cardiovascular/coronary heart disease in the population with hypertension. Among the populations both with and without hypertension, no risk was found to be associated with HOMA2-IR quartiles however, a 1-unit increase in HOMA2-IR was associated with a significant risk of cardiovascular disease among the non-hypertensive group [hazard ratio 1.60 (95% CI 1.03-2.48); P = 0.03].

CONCLUSIONS

The presence of hypertension modified the impact of HOMA-IR/HOMA2-IR on incident cardiovascular/coronary heart disease. The presence of insulin resistance highlighted a significant and independent risk for cardiovascular disease/coronary heart disease only in the population without hypertension.

Islet Volume and Indexes of β-Cell Function in Humans

Islet volume and endocrine pancreas architecture (islet size distribution) may be independent determinants of β-cell function. Furthermore, the accuracy of homeostatic model assessment (HOMA) indexes in predicting β-cell mass has never been assessed. Here we investigated the relationships between islet volume, islet density, and islet size distribution, estimated after pancreatic tissue digestion, with established indexes of β-cell function in humans. We included in this study 42 patients who were candidates for islet autotransplantation and had well-characterized glucose metabolism. Indexes of insulin secretion were calculated and compared with the islet volume, as a surrogate of β-cell mass, obtained after digestion of pancreas. Islet counting analysis showed considerable interindividual variation in islet density and size. Islet volume, but not density nor size, was the only independent determinant of β-cell function assessed by insulin HOMA β-cell. Islet volume was significantly reduced in the patients with overt hyperglycemia, but not in patients with impaired fasting glucose. Insulin HOMA β-cell predicted islet volume better than other measures of fasting insulin secretion. In conclusion, the present study documented a close direct relationship between indexes of β-cell function and islet volume in humans. The insulin HOMA β-cell provides a more reliable estimate of pancreatic islet volume than fasting glucose before islet isolation.

HOMA-IR and the risk of hyperuricemia: a prospective study in non-diabetic Japanese men

AIMS

To examine the relation of insulin resistant status determined by homeostasis model assessment of insulin resistance (HOMA-IR) with the risk of incident hyperuricemia.

METHODS

The study participants included 2071 Japanese men without hyperuricemia and diabetes, aged 35-54 years. The participants had undergone annual heath examinations for 6 years to compare incident hyperuricemia (serum uric acid >416.4μmol/L (7.0mg/dL) and/or taking medication for hyperuricemia) in four groups based on quartiles of baseline HOMA-IR.

RESULTS

During follow-up there were 331 incident cases of hyperuricemia. The hazard ratios for hyperuricemia, compared with HOMA-IR ≤0.66, were 1.42 (95% confidence interval 1.02-1.98) for HOMA-IR 0.67-0.98, 1.20 (0.86-1.68) for HOMA-IR 0.99-1.49 and 1.44 (1.04-1.98) for HOMA-IR ≥1.50 after adjustment for baseline serum uric acid, creatinine, hypercholesterolemia and hypertension status, age, alcohol intake, and smoking and exercise habits. The hazard ratio associated with an increase of one standard deviation in lnHOMA-IR (1.85 as one geometric standard deviation of HOMA-IR) was 1.14 (1.03-1.28) (p for trend=0.02).

CONCLUSIONS

Increased HOMA-IR independently predicted the subsequent development of hyperuricemia. Insulin resistance itself or compensatory hyperinsulinemia may contribute to the development of hyperuricemia.

Prevalence of insulin resistance and cardiometabolic risk in Korean children and adolescents: a population-based study

AIMS

We aimed to establish normal reference values of serum insulin and the homeostasis model assessment of insulin resistance (HOMA-IR). We also aimed to verify HOMA-IR "cut-off values" in predicting cardiometabolic risk among Korean children and adolescents.

METHODS

Data from 2716 Korean subjects (1421 male and 1295 female, aged 10-20 years) were evaluated. Insulin resistance was defined as HOMA-IR >95th percentile. The odds ratios of cardiometabolic risk were assessed based on the state of insulin resistance.

RESULTS

Reference values of insulin and HOMA-IR were determined according to sex and age, based on data obtained from normal-weight subjects with normal fasting glucose levels. HOMA-IR values appeared to peak at the age of 14-15 years in male subjects and at the age of 12-13 years in female subjects. The prevalence of insulin resistance in the subjects was 9.8% (male=10.9%, female=8.6%). The prevalence of insulin resistance in normal-weight, overweight, and obese subjects were 4.7%, 25.6%, and 47.1% respectively. Subjects with insulin resistance had a higher prevalence of metabolic syndrome (odds ratios=18.33; 95% confidence interval, 9.62-34.94) and its components, especially hyperglycemia and hypertriglyceridemia.

CONCLUSION

We established reference values of serum insulin and HOMA-IR according to age and sex. Obesity is the most important risk factor for insulin resistance and metabolic syndrome. However, insulin resistance independently increases cardiometabolic risk. This information may be useful for Korean as well as other Asian in planning programs for the prevention of type 2 diabetes.

Paternal metabolic and cardiovascular risk factors for fetal growth restriction: a case-control study

OBJECTIVE

Fathers of low-birth weight offspring are more likely to have type 2 diabetes and cardiovascular disease in later life. We investigated whether paternal insulin resistance and cardiovascular risk factors were evident at the time that fetal growth-restricted offspring were born.

RESEARCH DESIGN AND METHODS

We carried out a case-control study of men who fathered pregnancies affected by fetal growth restriction, in the absence of recognized fetal disease (n = 42), compared with men who fathered normal-birth weight offspring (n = 77). All mothers were healthy, nonsmoking, and similar in age, BMI, ethnicity, and parity. Within 4 weeks of offspring birth, all fathers had measures of insulin resistance (HOMA index), blood pressure, waist circumference, endothelial function (flow-mediated dilatation), lipid profile, weight, and smoking habit. Comparison was made using multivariable logistical regression analysis.

RESULTS

Fathers of fetal growth-restricted offspring [mean (SD) 1.8th (2.2) customized birth centile] were more likely to have insulin resistance, hypertension, central adiposity, and endothelial dysfunction and to smoke cigarettes compared with fathers of normal grown offspring. After multivariable analysis, paternal insulin resistance and smoking remained different between the groups. Compared with fathers of normal grown offspring, men who fathered pregnancies affected by fetal growth restriction had an OR 7.68 (95% CI 2.63-22.40; P < 0.0001) of having a 1-unit higher log HOMA-IR value and 3.39 (1.26-9.16; P = 0.016) of being a smoker.

CONCLUSIONS

Men who recently fathered growth-restricted offspring have preclinical evidence of the insulin resistance syndrome and are more likely to smoke than fathers of normal grown offspring. Paternal lifestyle may influence heritable factors important for fetal growth.

Insulin Resistance and Risk of Cerebral Infarction in a Japanese General Population

The aim of the study was to investigate the relation between insulin resistance and risk of cerebral infarction in a Japanese general population. The subjects were 2610 men and women without past history of stroke or myocardial infarction and who were under treatment for diabetes. Subjects were divided into quartiles by the homeostasis model assessment of insulin resistance (HOMA-IR), and Cox’s proportional hazard model was used to calculate hazard ratios (HRs) for cerebral infarction. In men, the multivariate-adjusted HRs were 2.51 (95% confidence interval [CI] = 0.98-6.42) in quartile 1 (Q1), 1.43 (95% CI = 0.54-3.82) in Q2, and 2.13 (95% CI = 0.82-5.51) in Q4, using Q3 as the reference. In women, the multivariate-adjusted HRs were 2.12 (95% CI = 0.72-6.31) in Q1, 2.96 (95% CI = 1.06-8.26) in Q3, and 2.31 (95% CI = 0.80-6.69) in Q4, using Q2 as the reference. The association between risk of cerebral infarction and HOMA-IR was not dose dependent.

Glucose intolerance and insulin resistance as predictors of low platelet response to clopidogrel in patients with minor ischemic stroke or TIA

The relation between high on-treatment platelet reactivity (HPR), and the level of glucose intolerance and insulin resistance (IR) was studied in clopidogrel-treated patients with minor ischemic stroke or TIA. The cohort consisted of 66 patients, 11 of which had known type 2 diabetes mellitus (DM). Platelet aggregation in whole blood (Multiplate™) and metabolic variables were measured 1 month after acute onset of neurological symptoms. Glucose tolerance was measured by Oral Glucose Tolerance Test (OGTT). IR was estimated by homeostasis model assessment HOMA-IR. Patients were categorized as "responders" (R) or "non-responders" (NR) to clopidogrel according to an established cut-off in platelet aggregation induced by adenosine diphosphate (ADP). In total, 14/66 (21%) patients were NR. Impaired glucose tolerance (IGT), impaired fasting glucose (IFG) or DM was seen in 13/14 NR (93%), while for R this was the case in 25/52 (48%), p = 0.001. The percentage of NR was 33% in patients with DM and 35% in patients with IGT or IFG. In the group with normal glucose tolerance (NGT) the percentage of NR was low, 4% (1/28). Fasting plasma glucose (f-PG) was higher for NR than for R, 6.0 (5.5-6.7) mM vs. 5.3 (5.0-6.0) mM, p = 0.023. Glycated hemoglobin (HbA1c) did not differ between NR and R. NR also had higher arachidonic acid-induced platelet aggregation than R, and a tendency towards higher aggregation induced by thrombin receptor agonist peptide (TRAP), indicating that HPR reflects a global platelet hyper-reactivity. HOMA-IR was calculated for 52 of the patients above without known diabetes, 9 of which were NR (17%). NR were significantly more insulin resistant than R, with median HOMA-IR 4.5 (3.0-7.4) compared to 2.1 (1.5-3.2) for R, p = 0.001. HOMA-IR and fasting plasma insulin were the only metabolic variables with significant relationships to ADP-induced platelet aggregation. The results suggest that HPR develops in the pre-diabetic phase. A metabolic disturbance with glucose intolerance and/or high level of IR was a pre-requisite for HPR in the tested cohort. Conversely, normal glucose tolerance combined with normal or mildly elevated HOMA-IR excluded HPR. NR are likely to constitute a high-risk group among patients with ischemic cerebrovascular disease. Measurement of f-PG or HbA1c is insufficient to identify NR, while OGTT and HOMA-IR are more predictive.

Insulin resistance and the risk of stroke and stroke subtypes in the nondiabetic elderly

Insulin resistance, which plays a key role in the development of diabetes mellitus, is a putative modifiable risk factor for stroke. The aim of this study was to investigate if markers of insulin resistance were associated with risk of stroke in the general elderly population. This study was part of the large population-based Rotterdam Study and included 5,234 participants who were aged 55 years or older and stroke free and diabetes free at baseline (1997-2001). Fasting insulin levels and homeostasis model assessment for insulin resistance were used as markers for insulin resistance. Cox regression was used to determine associations between insulin resistance markers and stroke risk, adjusted for age, sex, and potential confounders. During 42,806 person-years of follow-up (median: 8.6 years), 366 first-ever strokes occurred, of which 225 were cerebral infarctions, 42 were intracerebral hemorrhages, and 99 were unspecified strokes. Fasting insulin levels were not associated with risk of any stroke, cerebral infarction, or intracerebral hemorrhage. Homeostasis model assessment for insulin resistance, which almost perfectly correlated with fasting insulin levels, was also not associated with risk of stroke or stroke subtypes. In conclusion, in this population-based cohort study among nondiabetic elderly, insulin resistance markers were not associated with risk of stroke or any of its subtypes.

A nutraceutical combination improves insulin sensitivity in patients with metabolic syndrome

AIM

To test the efficacy of a proprietary nutraceutical combination in reducing insulin resistance associated with the metabolic syndrome (MetS).

METHODS

Sixty-four patients with MetS followed at a tertiary outpatient clinic were randomly assigned to receive either placebo or a proprietary nutraceutical combination (AP) consisting of berberine, policosanol and red yeast rice, in a prospective, double-blind, placebo-controlled study. Evaluations were performed at baseline and after 18 wk of treatment. The homeostasis model assessment of insulin resistance (HOMA-IR) index was the primary outcome measure. Secondary endpoints included lipid panel, blood glucose and insulin fasting, after a standard mixed meal and after an oral glucose tolerance test (OGTT), flow-mediated dilation (FMD), and waist circumference.

RESULTS

Fifty nine patients completed the study, 2 withdrew because of adverse effects. After 18 wk there was a significant reduction in the HOMA-IR index in the AP group compared with placebo (ΔHOMA respectively -0.6 ± 1.2 vs 0.4 ± 1.9; P < 0.05). Total and low density lipoprotein cholesterol also significantly decreased in the treatment arm compared with placebo (Δlow density lipoprotein cholesterol -0.82 ± 0.68 vs -0.13 ± 0.55 mmol/L; P < 0.001), while triglycerides, high density lipoprotein cholesterol, and the OGTT were not affected. In addition, there were significant reductions in blood glucose and insulin after the standard mixed meal, as well as an increase in FMD (ΔFMD 1.9 ± 4.2 vs 0 ± 1.9 %; P < 0.05) and a significant reduction in arterial systolic blood pressure in the AP arm.

CONCLUSION

This short-term study shows that AP has relevant beneficial effects on insulin resistance and many other components of MetS.

Chronic ingestion of flavan-3-ols and isoflavones improves insulin sensitivity and lipoprotein status and attenuates estimated 10-year CVD risk in medicated postmenopausal women with type 2 diabetes: a 1-year, double-blind, randomized, controlled trial

OBJECTIVE

To assess the effect of dietary flavonoids on cardiovascular disease (CVD) risk in postmenopausal women with type 2 diabetes on established statin and hypoglycemic therapy.

RESEARCH DESIGN AND METHODS

Despite being medicated, patients with type 2 diabetes have elevated CVD risk, particularly postmenopausal women. Although dietary flavonoids have been shown to reduce CVD risk factors in healthy participants, no long-term trials have examined the additional benefits of flavonoids to CVD risk in medicated postmenopausal women with type 2 diabetes. We conducted a parallel-design, placebo-controlled trial with type 2 diabetic patients randomized to consume 27 g/day (split dose) flavonoid-enriched chocolate (containing 850 mg flavan-3-ols [90 mg epicatechin] and 100 mg isoflavones [aglycone equivalents)]/day) or matched placebo for 1 year.

RESULTS

Ninety-three patients completed the trial, and adherence was high (flavonoid 91.3%; placebo 91.6%). Compared with the placebo group, the combined flavonoid intervention resulted in a significant reduction in estimated peripheral insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR] -0.3 ± 0.2; P = 0.004) and improvement in insulin sensitivity (quantitative insulin sensitivity index [QUICKI] 0.003 ± 0.00; P = 0.04) as a result of a significant decrease in insulin levels (-0.8 ± 0.5 mU/L; P = 0.02). Significant reductions in total cholesterol:HDL-cholesterol (HDL-C) ratio (-0.2 ± 0.1; P = 0.01) and LDL-cholesterol (LDL-C) (-0.1 ± 0.1 mmol/L; P = 0.04) were also observed. Estimated 10-year total coronary heart disease risk (derived from UK Prospective Diabetes Study algorithm) was attenuated after flavonoid intervention (flavonoid +0.1 ± 0.3 vs. placebo 1.1 ± 0.3; P = 0.02). No effect on blood pressure, HbA(1c), or glucose was observed.

CONCLUSIONS

One-year intervention with flavan-3-ols and isoflavones improved biomarkers of CVD risk, highlighting the additional benefit of flavonoids to standard drug therapy in managing CVD risk in postmenopausal type 2 diabetic patients.

Insulin resistance: Is it time for primary prevention?

Insulin resistance is a clinical condition characterized by a decrease in sensitivity and responsiveness to the metabolic actions of insulin, so that a given concentration of insulin produces a less-than-expected biological effect. As a result, higher levels of insulin are needed to maintain normal glucose tolerance. Hyperinsulinemia, indeed, is one of the principal characteristics of insulin resistance states. This feature is common in several pathologic conditions, such as type 2 diabetes, obesity, and dyslipidemia, and it is also a prominent component of hypertension, coronary heart disease, and atherosclerosis. The presence of endothelial dysfunction, related to insulin resistance, plays a key role in the development and progression of atherosclerosis in all of these disorders. Insulin resistance represents the earliest detectable abnormality in type 2 diabetes, and is one of the major underlying mechanisms of hypertension and cardiovascular diseases. Its early detection could be of great importance, in order to set a therapeutic attack and to counteract the higher risk of diabetes and cardiovascular diseases.

Proposed cutoff level of waist circumference in Japanese men: evaluation by homeostasis model assessment of insulin resistance levels

OBJECTIVE

The aim of this study is to propose the cutoff level of waist circumference (WC) on the basis of homeostasis model assessment of insulin resistance (HOMA-IR) levels in order to diagnose metabolic syndrome (MetS).

METHODS

We examined a total of 798 non-diabetic men (40-65 years of age) by using a receiver operating characteristic (ROC) curve to determine the cutoff level that yielded the maximum sensitivity plus specificity. According to the criteria proposed by the International Diabetes Federation (IDF), and the Japanese Society of Internal Medicine (JSIM), subjects with ≥ 2 metabolic components other than abdominal obesity, were considered to have MetS.

RESULTS

The overall prevalence rates of IDF- and JSIM-MetS were 17.4% (n=139) and 15.5% (n=124), respectively. The median levels of WC and HOMA-IR were 83.1 [interquartile range (IQR): 78.5-88.4] cm and 0.84 (IQR: 0.61-1.19), respectively. HOMA-IR was highly correlated with each metabolic parameter (each p<0.05), and in addition, multiple linear regression analysis of HOMA-IR (adjusted R²=0.459) showed that WC level was the strongest independent predictors of HOMA-IR level (F=141.1, p<0.05). According to ROC curve analysis, the cutoff level of HOMA-IR for predicting IDF- and JSIM-MetS was 0.92 for both (sensitivity: 79.9% and 78.2%, specificity: 64.9% and 63.6%). Based on the HOMA-IR level, the proposed WC cutoff level was 82.7 cm (sensitivity: 75.4%, specificity: 63.8%).

CONCLUSION

This study suggests that WC level should be more strictly managed than current criteria, for preventing the development of MetS in non-diabetic middle-aged Japanese men.

A systematic evaluation of the insulin resistance syndrome as an independent risk factor for cardiovascular disease mortality and derivation of a clinical index

Insulin resistance-related risk factor clustering (the insulin resistance syndrome or IRS) may be a cardiovascular disease (CVD) risk factor, but a convincing demonstration of this requires a rigorously derived reference measure and a systematic evaluation of measures and indices that derive from that measure. Using established IRS characteristics, factor analysis in 832 white men, generally healthy at baseline, generated a priori an IRS reference measure. An IRS diagnostic was chosen by evaluating CVD mortality risk in percentiles of the reference measure. An IRS clinical index was derived by (1) identification of readily measured, independent predictors of the IRS reference measure by multiple linear regression; (2) assignment to each predictor of a cut point optimal for discrimination of participants diagnosed with IRS; and (3) selection of a combination of the dichotomized predictors that further optimized IRS discrimination. The reference IRS diagnostic was defined by the top 16.7% of the IRS reference measure and predicted CVD mortality in Cox proportional hazards modeling (hazard ratio, 2.7; 95% confidence interval, 1.5-5.2; P = .002). An optimized IRS index was defined by triglycerides of at least 1.6 mmol/L and uric acid of at least 400 μmol/L plus any one of fasting plasma glucose of at least 5.4 mmol/L, diastolic blood pressure of at least 90 mm Hg, or body mass index of at least 27.0 kg/m(2) and predicted CVD mortality (hazard ratio, 2.14 [1.08-4.24]; P = .02). Prediction was independent of hypertension, hypercholesterolemia, and smoking. Conventionally derived glucoregulatory insulin resistance and metabolic syndrome were not predictive. The IRS is an independent risk factor for CVD mortality; and an effective, clinically usable index can be derived from readily measured variables.

Fatty liver index and mortality: the Cremona study in the 15th year of follow-up

A fatty liver, which is a common feature in insulin-resistant states, can lead to chronic liver disease. It has been hypothesized that a fatty liver can also increase the rates of non-hepatic-related morbidity and mortality. Therefore, we wanted to determine whether the fatty liver index (FLI), a surrogate marker and a validated algorithm derived from the serum triglyceride level, body mass index, waist circumference, and γ-glutamyltransferase level, was associated with the prognosis in a population study. The 15-year all-cause, hepatic-related, cardiovascular disease (CVD), and cancer mortality rates were obtained through the Regional Health Registry in 2011 for 2074 Caucasian middle-aged individuals in the Cremona study, a population study examining the prevalence of diabetes mellitus in Italy. During the 15-year observation period, 495 deaths were registered: 34 were hepatic-related, 221 were CVD-related, 180 were cancer-related, and 60 were attributed to other causes. FLI was independently associated with the hepatic-related deaths (hazard ratio = 1.04, 95% confidence interval = 1.02-1.05, P < 0.0001). Age, sex, FLI, cigarette smoking, and diabetes were independently associated with all-cause mortality. Age, sex, FLI, systolic blood pressure, and fibrinogen were independently associated with CVD mortality; meanwhile, age, sex, FLI, and smoking were independently associated with cancer mortality. FLI correlated with the homeostasis model assessment of insulin resistance (HOMA-IR), a surrogate marker of insulin resistance (Spearman's ρ = 0.57, P < 0.0001), and when HOMA-IR was included in the multivariate analyses, FLI retained its association with hepatic-related mortality but not with all-cause, CVD, and cancer-related mortality.

CONCLUSION

FLI is independently associated with hepatic-related mortality. It is also associated with all-cause, CVD, and cancer mortality rates, but these associations appear to be tightly interconnected with the risk conferred by the correlated insulin-resistant state.