Insulin resistance syndrome predicts the risk of coronary heart disease and stroke in healthy middle-aged men: the 22-year follow-up results of the Helsinki Policemen Study

Exercise-induced effects on asprosin and indices of atherogenicity and insulin resistance in males with metabolic syndrome: a randomized controlled trial

Metabolic syndrome (MetS) development is associated with insulin resistance and obesity, with the progression of visceral adipose tissue playing a crucial role. Excessive adipose tissue is accompanied by an increase in the asprosin (ASP), which is responsible for carbohydrate metabolism and the regulation of hunger and satiety. Exercise affects the release of ASP, which may regulate metabolism accordingly. Due to the inconclusive results of the effect of exercise on ASP concentration in men with MetS, 12-week interventions were carried out in the following groups: EG1-aerobic training (n = 21, age: 34.21 ± 6.06, WC; waist circumference: 114.7 ± 10.93) and EG2-a combination of aerobic and resistance training (n = 21, age: 37.37 ± 7.08, WC: 114.8 ± 11.64) and compared with a control group (CG) of men with MetS without any intervention (n = 20, age: 38.26 ± 7.43, WC: 115.3 ± 10.54). Body composition, indicators of carbohydrate-lipid metabolism, and ASP were assessed four times: before the intervention, at 6 and 12 weeks of training, and 4 weeks after the training sessions. A comparison of the intervention influence on changes in the analyzed variables between the groups was performed using ANOVA test for dependent groups with post-hoc comparison. The effect size (ES) was also assessed using squared eta (η2). The implementation of aerobic training resulted in a decrease in ASP concentration (p = 0.03) within 6 weeks of the intervention, while in the CG a gradual increase in ASP was confirmed (p < 0.001). Aerobic-resistance training did not induce significant changes in ASP concentration but resulted in an increase in fat-free mass/fat mass (FFM/FM) ratio (p < 0.001), and a decrease (p = 0.04) in Homeostasis Model Assessment of Insulin Resistance (HOMA-IR). Changes in the visceral adipose tissue level indicate a gradual decrease in both the EG1 (p = 0.01) and EG2 (p = 0.04) groups. Both aerobic and aerobic-resistance exercises may have a regulatory effect, mainly by reducing visceral adipose tissue, on the improvement of metabolic disorders.

Alzheimer's disease and Alzheimer's disease-related dementias in Hispanics: Identifying influential factors and supporting caregivers

Alzheimer's disease (AD) and Alzheimer's disease-related dementias (ADRD) are the primary public health concerns in the United States and around the globe. AD/ADRD are irreversible mental illnesses that primarily impair memory and thought processes and may lead to cognitive decline among older individuals. The prevalence of AD/ADRD is higher in Native Americans, followed by African Americans and Hispanics. Increasing evidence suggests that Hispanics are the fastest-growing ethnic population in the USA and worldwide. Hispanics develop clinical symptoms of AD/ADRD and other comorbidities nearly seven years earlier than non-Hispanic whites. The consequences of AD/ADRD can be challenging for patients, their families, and caregivers. There is a significant increase in the burden of illness, primarily affecting Hispanic/Latino families. This is partly due to their strong sense of duty towards family, and it is exacerbated by the inadequacy of healthcare and community services that are culturally and linguistically suitable and responsive to their needs. With an increasing age population, low socioeconomic status, low education, high genetic predisposition to age-related conditions, unique cultural habits, and social behaviors, Hispanic Americans face a higher risk of AD/ADRD than other racial/ethnic groups. Our article highlights the status of Hispanic older adults with AD/ADRD. We also discussed the intervention to improve the quality of life in Hispanic caregivers.

Hyperinsulinemia, an overlooked clue and potential way forward in metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease is closely associated with other features of the metabolic syndrome such as type 2 diabetes. The progression of the disease may lead to liver fibrosis, which is the main predictor of major adverse liver outcomes. Insulin resistance plays a major role in the pathogenesis of the disease. A component of fasting hyperinsulinemia is a failure of the liver to adjust the peripheral level of insulin due to reduced clearance. The associated fasting hyperinsulinemia has been independently associated as a predictor of major adverse liver outcomes and major adverse cardiovascular events. In this review, we discuss the potential mechanism and entanglement between liver fibrosis and hyperinsulinemia, and we hypothesize that the measure of fasting insulin could become a hepatic functional test within the armamentarium of noninvasive tests for the assessment of Metabolic dysfunction-associated steatotic liver disease.

Clinical correlates of plasma insulin levels over the life course and association with incident type 2 diabetes: the Framingham Heart Study

INTRODUCTION

Insulin is a glucose-lowering hormone that affects carbohydrate, lipid, and protein metabolism. Limited data exist on the correlates of insulin levels over the life course in healthy community-dwelling individuals.

RESEARCH DESIGN AND METHODS

Using multilevel modeling of multiple serial observations over 21 years, we assessed the longitudinal correlates of fasting insulin and the cross-sectional correlates of fasting and 2-hour (2h, post 75 g glucose challenge) plasma insulin concentrations in 2140 relatively healthy Framingham Heart Study participants without diabetes (61% women; mean age, 42 years). We used multivariable-adjusted Cox regression to relate glycemic markers (fasting and 2h-insulin, fasting glucose, 2h-glucose, and hemoglobin A_1C) to the risk of type 2 diabetes during follow-up.

RESULTS

Over the life course, fasting insulin concentrations were inversely associated with age, male sex, and physical activity, whereas waist circumference, the total/high-density lipoprotein (HDL) cholesterol ratio, and blood triglycerides were positively associated with insulin levels (p<0.005 for all). Male sex (inversely related) and the total/HDL cholesterol ratio (positively related) emerged as the most important cross-sectional correlates of 2h-insulin (p<0.005 for all). All markers were associated with higher risk of type 2 diabetes (352 cases, median follow-up 18 years, p<0.001 for all).

CONCLUSIONS

We observed common and distinct correlates of fasting and 2h-insulin levels. Our findings highlight a potential role of insulin in lipid and lipoprotein metabolism. Furthermore, fasting and 2h-insulin are critical markers of future diabetes risk. Further studies are needed to confirm our findings.

Early menarche and its consequence in Korean female: reducing fructose intake could be one solution

The mean age at menarche (AAM) of Korean females has been rapidly decreasing over the last 50 years; currently, the prevalence of early menarche (<12 years) is 22.3%. Female adolescents who experience early menarche are known to be at greater risk of psychosocial and behavioral problems along with several physical health problems such as menstrual problems. They also tend to achieve a shorter final height and develop obesity. Population-based Korean studies have shown a strong association between early menarche and the risk of obesity, insulin resistance, metabolic syndrome, nonalcoholic fatty liver disease, diabetes, breast cancer, and cardiovascular disease in adulthood. Although the exact mechanism of how early menarche causes cardiometabolic derangement in later adulthood is unknown, childhood obesity and insulin resistance might be major contributors. Recent studies demonstrated that an excessive consumption of fructose might underlie the development of obesity and insulin resistance along with an earlier AAM. A positive association was observed between sugar-sweetened beverages (a major source of fructose) intake and obesity, metabolic syndrome, insulin resistance, and cardiometabolic risk in Korean females. In pediatrics, establishing risk factors is important in preventing disease in later life. In this regard, early menarche is a simple and good marker for the management of cardiometabolic diseases in adulthood. Decreasing one's fructose intake might prevent early menarche as well as the development of obesity, insulin resistance, and cardiometabolic diseases.

Investigation of Relationship between Occupational Stress and Cardiovascular Risk Factors among Nurses

Background:

One of the major causes of various work-related health problems among nurses is occupational stress. Hence, the main purpose of the present research was to find association between occupational stress of nurses and risk factors of cardiovascular disease.

Methods:

In this cross-sectional study, the Osipow job stress questionnaire was employed to assess the occupational stress among the 250 nurses in Emam Khomeini hospital of Tehran in 2018. Based on stress score for participants, subjects divided into two groups: Scoring of group one was 60–179 (mild and average stress) and group two between 180 and 300 (average to acute and acute stress). Systolic and diastolic blood pressures were recorded for subjects after 10hrs fasting. Then the blood samples were collected to measure cholesterol, triglyceride and glucose levels. For determining the association between education level, job experience and study groups, the Chi-square test and for comparing job stress between two groups of study the Mann–Whitney U test was used.

Results:

Subjects with job stress in group one was 70(28%) and group two was 180(72%). The association between level of education and two study groups was not significant (P=0.129) while between job experience and two study groups was significant (P=0.004). Mean of Blood glucose levels for group I (98.0± 37.5), was higher than group II (82.5±12.0) and statistically significant (P=0.001). No significant difference was found between two groups of study for other parameters.

Conclusion:

High level of work-related stress among subjects affected the values related to blood glucose level, but no significant relationship was found between other risk factors of cardiovascular diseases and occupational stress among nurses.

Hidden danger: A 22-years analysis of law enforcement deaths associated with duty-related illnesses (1997-2018)

Purpose –

Law enforcement is a dangerous profession not only due to assaults, accidents and homicides but also due to health risks. This study examined trends in the national frequency and rate of law enforcement jobrelated illness deaths in the United States over a 22-year period (1997-2018).

Design/methodology/approach –

Data were obtained from the National Law Enforcement Officers Memorial Fund (NLEOMF) on death frequencies related to health issues at work. Death rates were based on the total number of police officers in the United States [rate = (frequency/population at risk) × 100,000]. Trends were examined using standardized regression.

Findings –

A total of 646 deaths were attributed to job-related illness. There was a significant upward trend in overall job-related illness deaths (frequency analyses: β = 0.88, p < 0.0001; rate analyses: β = 0.82, p ≤ 0.0001) mainly driven by a significant increase in 911 cancer deaths (frequency analyses: β = 0.88, p < 0.0001; rate analyses: β = 0.88, p ≤ 0.0001). Nearly 82 percent of circulatory deaths were from a heart attack, with an average death age of 46.5 years.

Research limitations/implications –

Deaths were not included if they failed to meet medical requirements of the NLEOMF. The data are descriptive, do not estimate risk and should be interpreted cautiously.

Practical implications –

Police wellness programs may help to reduce the danger of deaths associated with job-related illness.

Originality/value –

This is among the first studies to examine frequency and rate of police health-related deaths due to job exposures.

Food Liking-Based Diet Quality Indexes (DQI) Generated by Conceptual and Machine Learning Explained Variability in Cardiometabolic Risk Factors in Young Adults

The overall pattern of a diet (diet quality) is recognized as more important to health and chronic disease risk than single foods or food groups. Indexes of diet quality can be derived theoretically from evidence-based recommendations, empirically from existing datasets, or a combination of the two. We used these methods to derive diet quality indexes (DQI), generated from a novel dietary assessment, and to evaluate relationships with cardiometabolic risk factors in young adults with (n = 106) or without (n = 106) diagnosed depression (62% female, mean age = 21). Participants completed a liking survey (proxy for usual dietary consumption). Principle component analysis of plasma (insulin, glucose, lipids) and adiposity (BMI, Waist-to-Hip ratio) measures formed a continuous cardiometabolic risk factor score (CRFS). DQIs were created: theoretically (food/beverages grouped, weighted conceptually), empirically (grouping by factor analysis, weights empirically-derived by ridge regression analysis of CRFS), and hybrid (food/beverages conceptually-grouped, weights empirically-derived). The out-of-sample CRFS predictability for the DQI was assessed by two-fold and five-fold cross validations. While moderate consistencies between theoretically- and empirically-generated weights existed, the hybrid outperformed theoretical and empirical DQIs in cross validations (five-fold showed DQI explained 2.6% theoretical, 2.7% empirical, and 6.5% hybrid of CRFS variance). These pilot data support a liking survey that can generate reliable/valid DQIs that are significantly associated with cardiometabolic risk factors, especially theoretically- plus empirically-derived DQI.

The prevalence, risk factors, and clinical characteristics of insulin resistance in Chinese patients with schizophrenia

BACKGROUND

Studies have shown that patients with schizophrenia are at a high risk of developing insulin resistance (IR). We investigated the prevalence of IR and its clinical correlates in hospitalized Chinese patients with schizophrenia.

METHODS

A total of 193 patients with schizophrenia (113 males and 80 females) were recruited for the study. We collected their demographic and clinical data, including data on their plasma glucose and lipid levels. All patients were rated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to assess cognitive function, while Positive and Negative Syndrome Scale (PANSS) was used to assess psychopathology. The cut-off value for the homeostasis model assessment of insulin resistance (HOMA-IR) was set at 1.7.

RESULTS

The prevalence of IR was 37.82% (73/193). The IR patients had significantly higher waist-to-hip ratio and body mass index (BMI), and higher fasting plasma glucose (FPG), triglyceride (TG), and low density lipoprotein (LDL) levels compared to non-IR patients (all p<.05). Binary logistic regression analysis showed that smoking, BMI, and TG and LDL levels are significant predictors of IR. In addition, correlation analysis showed that IR was significantly correlated with the waist-to-hip ratio, BMI, and LDL level (Bonferroni corrected p<.05). The multivariable linear regression analysis indicated that the BMI and FPG are associated with the IR index. There was no significant difference in IR index between patients who were taking different antipsychotics.

CONCLUSION

We found a high prevalence of IR and its risk factors in Chinese patients with schizophrenia. Active weight control to reduce the BMI and waist circumference and reducing the number of cigarettes consumed, may be essential to decrease the incidence of IR in patients with schizophrenia.

Application of metabolomics for unveiling the therapeutic role of traditional Chinese medicine in metabolic diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicine has been practiced for thousands of years in China and some Asian countries. Traditional Chinese Medicine (TCM) is characterized as multi-component and multiple targets in disease therapy, and it is a great challenge for elucidating the mechanisms of TCM.

AIM OF THE REVIEW

Comprehensively summarize the application of metabolomics in biomarker discovery, stratification of TCM syndromes, and mechanism underlying TCM therapy on metabolic diseases.

METHODS

This review systemically searched the publications with key words such as metabolomics, traditional Chinese medicine, metabolic diseases, obesity, cardiovascular disease, diabetes mellitus in "Title OR Abstract" in major databases including PubMed, the Web of Science, Google Scholar, Science Direct, CNKI from 2010 to 2019.

RESULTS

A total of 135 papers was searched and included in this review. An overview of articles indicated that metabolic characteristics may be a hallmark of different syndromes/models of metabolic diseases, which provides a new perspective for disease diagnosis and therapeutic optimization. Moreover, TCM treatment has significantly altered the metabolic perturbations associated with metabolic diseases, which may be an important mechanism for the therapeutic effect of TCM.

CONCLUSIONS

Until now, many metabolites and differential biomarkers related to the pathogenesis of metabolic diseases and TCM therapy have been discovered through metabolomics research. Unfortunately, the biological role and mechanism of disease-related metabolites were largely unclarified so far, which warrants further investigation.

Prevalence of metabolic syndrome and its risk factors among 10,348 police officers in a large city of China: A cross-sectional study

The aim of this study was to assess the prevalence of metabolic syndrome (MS) and its risk factors among the police officers in a large city of China.A cross-sectional study was conducted in 10,348 police officers in 2017 in Changsha, a provincial capital located in central-south China. All participants underwent a physical examination to measure the compotents of MS and completed a questionnaire to collect data on potential risk factors. According to the current guidelines of China, MS was defined as the presence of any 3 of the following five traits: abdominal obesity, defined as a waist circumference ≥90 cm in men and ≥85 cm in women; fasting serum triglycerides ≥1.70 mmol/L, or drug treatment for elevated triglycerides; fasting serum high-density lipoprotein cholesterol <1.03 mmol/L, or drug treatment for low high-density lipoprotein cholesterol; blood pressure ≥130/85 mmHg, or drug treatment for elevated blood pressure; fasting plasma glucose ≥6.1 mmol/L, or 2-hour plasma glucose ≥7.8 mmol/L after a 75-g oral glucose load, or drug treatment for elevated blood glucose.The prevalence of MS was 23.2% (95% confidence interval [CI]: 22.2%-24.2%). The main risk factors associated with MS were older age (odds ratio [OR] 1.546, 95% CI 1.431-1.670), being male (OR 11.256, 95%CI 7.147-17.726), alcohol consumption (OR 1.250, 95% CI 1.070-1.461), and tobacco use (OR 1.398, 95% CI 1.232-1.586). Exercise was associated with decreased risk of MS (OR 0.865, 95% CI 0.755-0.991).The prevalence of MS was low in the study population. Its risk factors were similar to those identified in the general population of China. Lifestyle intervention is warranted in policemen to reduce the risk of MS and prevent diabetes and cardiovascular disease.

An update on metabolic syndrome: Metabolic risk markers and adipokines in the development of metabolic syndrome

Metabolic syndrome is a collection of physiological and biochemical abnormalities about 20-25% of adult population in developing countries is suffering from metabolic syndrome. Previous research demonstrated that adipose tissue plays an important role in energy regulation via endocrine, paracrine and autocrine signals as results of obesity due to accumulation of adipose tissue to excess that by time affects negatively both physical and psychological health and well being, it has been found that adipose tissues produces a variety of factors known as "adipokines" which play a key role in the development and progression of the disease and also hypothesized that adipokines are a possible link between obesity and the other risk components of the Metabolic syndrome. Many of the adipokines exert multiple actions in a variety of cellular processes leading to a complex array of abnormal characteristic of Metabolic syndrome. Abnormal production of these adipokines by expanded visceral fat during Adiposity contributes to a pro-inflammatory state. Increasing evidence suggests that aberrant production/release of adipokine from adipocyte i.e. adiponectin, leptin and resistin etc, may contribute to the health problems associated with Adiposity such as dyslipidemia, insulin resistance and atherosclerosis. This study conclusively have shown a significant role of adipokines secreted by adipose tissue and various metabolic risk markers play a important role in the development of Metabolic syndrome.

Fixed-dose combination of alogliptin/pioglitazone improves glycemic control in Japanese patients with type 2 diabetes mellitus independent of body mass index

This study investigated the effects of switching from combination therapy with either alogliptin (Alo) or pioglitazone (Pio) to fixed-dose combination therapy (FDCT) with alogliptin and pioglitazone (Alo-Pio FDCT). The usefulness and efficacy of Alo-Pio FDCT were investigated. A total of 50 outpatients with type 2 diabetes mellitus (T2DM) treated with Alo and 47 outpatients with T2DM treated with Pio were switched to Alo-Pio FDCT, and its efficacy and usefulness were evaluated. Significant improvements were observed in hemoglobinA1c (HbA_1c), alanine transaminase (ALT), and γ-glutamyl transpeptidase (GGT) levels after switching to Alo-Pio FDCT for 16 weeks in both groups. Only the group switching from Alo to Alo-Pio FDCT showed significant improvements in high-density lipoprotein cholesterol (HDL) levels and triglyceride levels. In a multivariate logistic regression model of the variation in the change of HbA_1c at 16 weeks, ALT and GGT were independent predictors of the change of HbA_1c at 16 weeks. In addition, the switch to Alo-Pio FDCT improved glycemic control to a certain degree regardless of BMI. Switching from either Alo or Pio to Alo-PIO FDCT may, unlike monotherapy with a DPP-4 inhibitor, be effective for patients with T2DM regardless of whether they are obese or lean.

Cardiovascular health profile among Québec male and female police officers

To document the cardiovascular health profile of Québec police officers (PO). Participants answered an online questionnaire evaluating the presence of cardiovascular disease (CVD) risk factors and symptoms. Two thousand, ninety-nine (2,099) male (age: 40.8 ± 9.2 years) and 756 female (age: 37.9 ± 7.9 years) PO participated in this study. The prevalence of obesity (body mass index ≥30 kg/m²) and diagnosed hypertension was respectively 21.1, and 14.3% in male and 7.3 and 4.1% in female PO. According to 2013 American College of Sports Medicine guidelines, 27.0 and 48.0% of male and 12.1 and 56.7% of female PO were categorized as being at moderate and high CVD risk, respectively. These findings suggest that Québec police departments should help PO to adopt and maintain a healthy lifestyle to decrease CVD risk.

Effects of antiretroviral combination therapies F/TAF, E/C/F/TAF and R/F/TAF on insulin resistance in healthy volunteers: the TAF-IR Study

BACKGROUND

Increased insulin resistance (IR), associated with specific antiretroviral drugs or drug classes, is an established risk factor for type 2 diabetes in HIV patients, ultimately increasing morbidity and mortality. To date, data on the risk of IR in tenofovir alafenamide (TAF)-based protocols are unavailable.

METHODS

This prospective randomized, open-label study evaluated the effects of IR on 30 healthy volunteers receiving fixed-dose combinations (FDCs) of emtricitabine/tenofovir alafenamide (F/TAF), elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or rilpivirine/emtricitabine/tenofovir alafenamide (R/F/TAF). IR was measured before and after 14-day treatments using the hyperinsulinemic-euglycaemic clamp technique (HEGC). Changes in IR in each group were evaluated using the mean glucose disposal rate, normalized with body weight (M_BW [mg glucose/(min×kg)]).

RESULTS

A total of 30 subjects underwent randomization: one subject in the F/TAF arm withdrew consent after randomization and one in the R/F/TAF arm had to be excluded because of technical failure during HEGC, resulting in 28 subjects in the per-protocol population (F/TAF, n=9 subjects; E/C/F/TAF, n=10 subjects; R/F/TAF n=9 subjects). No significant differences were detected on the baseline characteristics. IR did not differ among the groups before treatment. None of the studied antiretroviral combinations resulted in a significant change in IR after 14 days compared with baseline values, as measured by M_BW (F/TAF, 11.42 ±3.04 mean [±sd] versus 11.43 ±3.23, P=0.49; E/C/F/TAF, 10.04 ±2.49 versus 10.95 ±4.26, P=0.30; R/F/TAF, 11.03 ±1.96 versus 13.01 ±4.11, P=0.13).

CONCLUSIONS

Short-term treatment for F/TAF, E/C/F/TAF or R/F/TAF did not increase IR in healthy male volunteers.

Glucose challenge metabolomics implicates medium-chain acylcarnitines in insulin resistance

Insulin resistance (IR) predisposes to type 2 diabetes and cardiovascular disease but its causes are incompletely understood. Metabolic challenges like the oral glucose tolerance test (OGTT) can reveal pathogenic mechanisms. We aimed to discover associations of IR with metabolite trajectories during OGTT. In 470 non-diabetic men (age 70.6 ± 0.6 years), plasma samples obtained at 0, 30 and 120 minutes during an OGTT were analyzed by untargeted liquid chromatography-mass spectrometry metabolomics. IR was assessed with the hyperinsulinemic-euglycemic clamp method. We applied age-adjusted linear regression to identify metabolites whose concentration change was related to IR. Nine trajectories, including monounsaturated fatty acids, lysophosphatidylethanolamines and a bile acid, were significantly associated with IR, with the strongest associations observed for medium-chain acylcarnitines C10 and C12, and no associations with L-carnitine or C2-, C8-, C14- or C16-carnitine. Concentrations of C10- and C12-carnitine decreased during OGTT with a blunted decline in participants with worse insulin resistance. Associations persisted after adjustment for obesity, fasting insulin and fasting glucose. In mouse 3T3-L1 adipocytes exposed to different acylcarnitines, we observed blunted insulin-stimulated glucose uptake after treatment with C10- or C12-carnitine. In conclusion, our results identify medium-chain acylcarnitines as possible contributors to IR.

Association between single nucleotide polymorphism rs11057401 of CCDC92 gene and the risk of coronary heart disease (CHD)

Background

Given that the CCDC92 (coiled-coil domain containing 92) was important in insulin resistance, we sought to investigate whether the CCDC92 rs825476 SNP is associated with the risk of CHD in Chinese Han population.

Methods

Rs11057401 was genotyped for 817 patients with CHD and 724 age- and sex-matched controls using PCR-based Invader assay with the probe sets designed and synthesized by third wave.

Results

Patients were found to have a significantly higher frequency of AA than the controls (23.5% vs. 14.7%, OR = 1.60, p = 0.000), and the frequency of allele A was found to be remarkably higher in the patients than the controls (48.1% vs. 40.3%, OR = 1.19, p = 0.000). Multivariate logistic analysis showed that the incidence of CHD was positively correlated with hyperlipidemia, T2D and rs11057401 AA/AT genotypes. The FPG, TC, and ApoA1 levels in the CHD patients were different among the AA, AT and TT genotypes (P < 0.05), the A allele carriers had higher FPG, TC and lower ApoA1 levels than the A allele non-carriers (P < 0.05).

Conclusion

The genotypic and allelic frequencies of the rs11057401 SNP were significantly different between the patients with CHD and controls. Subjects with AA genotype or A allele were associated with an increased risk of CHD. The AA/AT genotypes were also associated with increased serum FPG, TC and decreased ApoA1 in CHD.

Six weeks of combined aerobic and resistance exercise using outdoor exercise machines improves fitness, insulin resistance, and chemerin in the Korean elderly: A pilot randomized controlled trial

BACKGROUND

The aim of this study was to investigate the effect of a six-week-long exercise program using outdoor exercise equipment on fitness, insulin resistance and adipocytokines among Korean elderly.

METHODS

A total of 47 participants were randomized into one of the following three groups; control, resistance exercise or combined exercise (aerobic and resistance exercise). The resistance exercise group completed three resistance types of exercise. The combined exercise group completed five exercises, including three resistance types of exercise and two aerobic types of exercise. Participants' body composition, fitness level, homeostasis model assessment of insulin resistance (HOMA-IR), and adipocytokines were measured at baseline and at the end of six weeks.

RESULTS

After six weeks of exercise training, participants in the combined exercise group exhibited significant reduction in insulin, HOMA-IR and chemerin levels, while significant reduction was observed in HOMA-IR only in the resistance exercise group compared with the control group. Meanwhile, six weeks of exercise training, whether resistance exercise alone or combined, significantly improved upper body muscular strength/endurance and physical function compared to the control group.

CONCLUSIONS

Six weeks of combined exercise using outdoor exercise equipment was effective in improving fitness, HOMA-IR, circulating chemerin levels, and other known risk factors of chronic diseases.

Prevalence of overweight and obesity among police officers in Riyadh City and risk factors for cardiovascular disease

Background

Despite the prevalence of overweight and obesity and increases in associated diseases such as diabetes and heart disease in the Saudi population, no studies have addressed the spread of obesity among Saudi police officers. Therefore, the present study aimed to assess the prevalence of overweight and obesity and associations with biochemical parameters among the police in Riyadh.

Method

The study involved a cross-sectional survey of 160 police officers in Riyadh, Saudi Arabia. Anthropometric measurements, blood pressure, lipid profiles and fasting blood sugar levels were measured for all individuals.

Results

According to the results, the average body mass index (BMI) was 27.5 ± 5.1, indicating an increase in overweight in this population and 66.9% were overweight or obese. Moreover, the mean systolic and diastolic blood pressure values were 119.5 and 79.4 mmHg, respectively, within normal limits. The mean total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), and triglyceride (TG) levels were 187.5, 43.9, 119.5 and 124.5 mg/100 ml, respectively.

Discussion

These BMI and biochemical findings suggest a high proportion of overweight and obese individuals in the sample population, as well as an increase in the proportion of individuals with high levels of biochemical indicators who are therefore susceptible to heart disease and diabetes.

Conclusion

The study recommends using preventive programs to combat obesity and overweight and related diseases and conducting further studies using measures other than BMI.

An intervention to reduce sitting and increase light-intensity physical activity at work: Design and rationale of the 'Stand & Move at Work' group randomized trial

BACKGROUND

American workers spend 70-80% of their time at work being sedentary. Traditional approaches to increase moderate-vigorous physical activity (MVPA) may be perceived to be harmful to productivity. Approaches that target reductions in sedentary behavior and/or increases in standing or light-intensity physical activity [LPA] may not interfere with productivity and may be more feasible to achieve through small changes accumulated throughout the workday METHODS/DESIGN: This group randomized trial (i.e., cluster randomized trial) will test the relative efficacy of two sedentary behavior focused interventions in 24 worksites across two states (N=720 workers). The MOVE+ intervention is a multilevel individual, social, environmental, and organizational intervention targeting increases in light-intensity physical activity in the workplace. The STAND+ intervention is the MOVE+ intervention with the addition of the installation and use of sit-stand workstations to reduce sedentary behavior and enhance light-intensity physical activity opportunities. Our primary outcome will be objectively-measured changes in sedentary behavior and light-intensity physical activity over 12months, with additional process measures at 3months and longer-term sustainability outcomes at 24months. Our secondary outcomes will be a clustered cardiometabolic risk score (comprised of fasting glucose, insulin, triglycerides, HDL-cholesterol, and blood pressure), workplace productivity, and job satisfaction DISCUSSION: This study will determine the efficacy of a multi-level workplace intervention (including the use of a sit-stand workstation) to reduce sedentary behavior and increase LPA and concomitant impact on cardiometabolic health, workplace productivity, and satisfaction.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02566317 (date of registration: 10/1/2015).

The Glucose Tolerance Test, But Not HbA 1c, Remains the Gold Standard in Identifying Unrecognized Diabetes Mellitus and Impaired Glucose Tolerance in Hypertensive Subjects

The objective of this study was to compare the value of the oral glucose tolerance test (GTT), glycated hemoglobin concentration (HbA1c), and fasting plasma glucose (FPG) for identifying unrecognized diabetes mellitus (DM) and impaired glucose tolerance (IGT) in hypertensive subjects. One hundred forty-four consecutive subjects who were not known to have DM and who were attending the Hypertension Clinic underwent 24-hour ambulatory blood pressure (BP) monitoring. A GTT and an HbA1c measurement were also carried out. Abnormal results from GTT were found in 94 patients (65%). Results from FPG were not different between those with DM and IGT but were significantly higher than in the euglycemic subjects. The FPG was between 110-125 mg/dL (6.1-6.9 mmol/L) in 31% (n=20) of patients with IGT and in 53% (n=16) of those with DM. With use of the previously published criteria to diagnose DM of FPG ≥103 mg/dL (5.7 mmol/L) and HbA1c ≥5.9%, 33% of our diabetic subjects and 75% of those with IGT would have been misclassified as euglycemic. The previously reported cut-off point for HbA1c of >6.1% to diagnose DM was present in 77% of our patients with DM and in 14% (n=9) of the patients with IGT. Multiple regression analysis showed that an abnormal result from GTT was independent of the level of clinical or ambulatory BP, nocturnal BP dip, cholesterol level, smoking history, race, or class of antihypertensive medication taken. FPG levels or HbA1c, or their combination, are not accurate enough to identify DM or IGT in patients attending a hospital Hypertension Clinic. A GTT may be required in these patients to reliably identify those with DM or IGT.

Early menarche is associated with metabolic syndrome and insulin resistance in premenopausal Korean women

In pediatrics, identifying risk factors is important in planning the prevention of cardiovascular disease. The aim of this study was to determine whether there is an independent association between early menarche (<12 years) and metabolic syndrome (MetS) in Korean women. We analyzed data from 4463 premenopausal women from the Fourth Korea National Health and Nutrition Examination Survey-IV (2007-2009). MetS was defined by the International Diabetes Federation for Asians and insulin resistance (IR) was defined as HOMA-IR more than 3.05. The prevalence of MetS and IR was 7.9 and 15.0%. Women (55.6%) with MetS also showed IR. The prevalence of MetS was higher in both women with early menarche and late menarche (≥16 years) compared with the reference group (early, 12.8%; reference, 7.0%; late, 11.0%, both P = 0.002). However, the odds ratio for MetS was 3.54 (95% confidence interval (CI), 2.14-5.87) and for IR was 2.98 (95% CI, 1.99-4.47) after adjusting for age and other confounders such as lifestyle variables, reproductive variables and sociodemographic variables only in women with early menarche

CONCLUSION

Early menarche was associated with an increased risk of MetS and IR in premenopausal Korean women.

WHAT IS KNOWN

Early menarche is associated with higher risk of CVD-related death and all-cause mortality in Western studies. Early menarche is associated with higher risk of diabetes in Korean premenopausal women.

WHAT IS NEW

Early menarche (<12 years) is associated with metabolic syndrome and insulin resistance in nationally representative Korean premenopausal women. However, late menarche (>16 years) is not associated with metabolic syndrome after controlling for age and other confounders.

Which modifiable health risk behaviours are related? A systematic review of the clustering of Smoking, Nutrition, Alcohol and Physical activity ('SNAP') health risk factors

OBJECTIVE

There is a growing body of literature examining the clustering of health risk behaviours, but little consensus about which risk factors can be expected to cluster for which sub groups of people. This systematic review aimed to examine the international literature on the clustering of smoking, poor nutrition, excess alcohol and physical inactivity (SNAP) health behaviours among adults, including associated socio-demographic variables.

METHOD

A literature search was conducted in May 2014. Studies examining at least two SNAP risk factors, and using a cluster or factor analysis technique, or comparing observed to expected prevalence of risk factor combinations, were included.

RESULTS

Fifty-six relevant studies were identified. A majority of studies (81%) reported a 'healthy' cluster characterised by the absence of any SNAP risk factors. More than half of the studies reported a clustering of alcohol with smoking, and half reported clustering of all four SNAP risk factors. The methodological quality of included studies was generally weak to moderate. Males and those with greater social disadvantage showed riskier patterns of behaviours; younger age was less clearly associated with riskier behaviours.

CONCLUSION

Clustering patterns reported here reinforce the need for health promotion interventions to target multiple behaviours, and for such efforts to be specifically designed and accessible for males and those who are socially disadvantaged.

Polemics of pioglitazone: an appraisal in 2015

Pioglitazone is an inexpensive and effective oral drug for the treatment of Type 2 diabetes. It addresses insulin resistance, one of the core pathophysiological defects in Type 2 diabetes, at both the adipose tissue and skeletal muscle level. As a majority of Type 2 diabetics classically exhibit higher insulin resistance, pioglitazone may strike exactly at the Achilles heel in this core pathogenesis. However, with the emerging association of bladder cancer with pioglitazone, French and German regulators were the first to ban or restrict pioglitazone use in 2011. The Indian regulators also suspended pioglitazone, although this ban was revoked within a month. Recently, a 10-year longitudinal study commissioned by US FDA found no association between bladder cancer and pioglitazone. Nevertheless, this controversy created a huge outcry in the medical fraternity. This review article is an overview of the development of this topic and an attempt to provide perspective on this contemporary issue.

Glucose-lowering with exogenous insulin monotherapy in type 2 diabetes: dose association with all-cause mortality, cardiovascular events and cancer

AIMS

To evaluate the association between insulin exposure and all-cause mortality, incident major adverse cardiovascular events (MACE) and incident cancer in people with type 2 diabetes treated with insulin monotherapy.

METHODS

For this retrospective study, people with type 2 diabetes who progressed to insulin monotherapy from the year 2000 were identified from the UK Clinical Practice Research Datalink. The risks of progression to serious adverse outcomes were compared using Cox proportional hazards models. In the main analysis, insulin exposure was introduced into the model as prescribed international units per kilogram per day, as a cumulative, continuous, annually updated, time-dependent covariable.

RESULTS

A total of 6484 subjects with type 2 diabetes who progressed to treatment with insulin monotherapy from the year 2000 onwards were followed for a mean of 3.3 years. The event numbers were as follows: deaths, n = 1110; incident MACE, n = 342; incident cancers, n = 382. Unadjusted event rates were 61.3 deaths per 1000 person-years, 26.4 incident MACE per 1000 person-years and 24.6 incident cancers per 1000 person-years. The adjusted hazard ratios in relation to 1-unit increases in insulin dose were 1.54 [95% confidence interval (CI) 1.32-1.78] for all-cause mortality, 1.37 (95% CI 1.05-1.81) for MACE and 1.35 (95% CI 1.04-1.75) for cancer.

CONCLUSIONS

There was an association between increasing exogenous insulin dose and increased risk of all-cause mortality, MACE and cancer in people with type 2 diabetes. The limitations of observational studies mean that this should be further investigated using an interventional study design.

Is metabolic syndrome predictive of prevalence, extent, and risk of coronary artery disease beyond its components? Results from the multinational coronary CT angiography evaluation for clinical outcome: an international multicenter registry (CONFIRM)

Although metabolic syndrome is associated with increased risk of cardiovascular disease and events, its added prognostic value beyond its components remains unknown. This study compared the prevalence, severity of coronary artery disease (CAD), and prognosis of patients with metabolic syndrome to those with individual metabolic syndrome components. The study cohort consisted of 27125 consecutive individuals who underwent ≥64-detector row coronary CT angiography (CCTA) at 12 centers from 2003 to 2009. Metabolic syndrome was defined as per NCEP/ATP III criteria. Metabolic syndrome patients (n=690) were matched 1:1:1 to those with 1 component (n=690) and 2 components (n=690) of metabolic syndrome for age, sex, smoking status, and family history of premature CAD using propensity scoring. Major adverse cardiac events (MACE) were defined by a composite of myocardial infarction (MI), acute coronary syndrome, mortality and late target vessel revascularization. Patients with 1 component of metabolic syndrome manifested lower rates of obstructive 1-, 2-, and 3-vessel/left main disease compared to metabolic syndrome patients (9.4% vs 13.8%, 2.6% vs 4.5%, and 1.0% vs 2.3%, respectively; p<0.05), while those with 2 components did not (10.5% vs 13.8%, 2.8% vs 4.5% and 1.3% vs 2.3%, respectively; p>0.05). At 2.5 years, metabolic syndrome patients experienced a higher rate of MACE compared to patients with 1 component (4.4% vs 1.6%; p=0.002), while no difference observed compared to individuals with 2 components (4.4% vs 3.2% p=0.25) of metabolic syndrome. In conclusion, Metabolic syndrome patients have significantly greater prevalence, severity, and prognosis of CAD compared to patients with 1 but not 2 components of metabolic syndrome.

Effects of aldosterone on insulin sensitivity and secretion

Dr. Conn originally reported an increased risk of diabetes in patients with hyperaldosteronism in the 1950s, although the mechanism remains unclear. Aldosterone-induced hypokalemia was initially described to impair glucose tolerance by impairing insulin secretion. Correction of hypokalemia by potassium supplementation only partially restored insulin secretion and glucose tolerance, however. Aldosterone also impairs glucose-stimulated insulin secretion in isolated pancreatic islets via reactive oxygen species in a mineralocorticoid receptor-independent manner. Aldosterone-induced mineralocorticoid receptor activation also impairs insulin sensitivity in adipocytes and skeletal muscle. Aldosterone may produce insulin resistance secondarily by altering potassium, increasing inflammatory cytokines, and reducing beneficial adipokines such as adiponectin. Renin-angiotensin system antagonists reduce circulating aldosterone concentrations and also the risk of type 2 diabetes in clinical trials. These data suggest that primary and secondary hyperaldosteronism may contribute to worsening glucose tolerance by impairing insulin sensitivity or insulin secretion in humans. Future studies should define the effects of MR antagonists and aldosterone on insulin secretion and sensitivity in humans.

The factor structure of the metabolic syndrome in obese individuals with binge eating disorder

OBJECTIVE

Metabolic syndrome (MetS) is strongly linked with cardiovascular disease and type-II diabetes, but there has been debate over which metabolic measures constitute MetS. Obese individuals with binge eating disorder (BED) are one of the high risk populations for developing MetS due to their excess weight and maladaptive eating patterns, yet, the clustering patterns of metabolic measures have not been examined in this patient group.

METHODS

347 adults (71.8% women) were recruited for treatment studies for obese individuals with BED. We used the VARCLUS procedure in the Statistical Analysis System (SAS) to investigate the clustering pattern of metabolic risk measures.

RESULTS

The analysis yielded four factors: obesity (body-mass-index [BMI] and waist circumference), lipids (HDL and triglycerides), blood pressure (systolic and diastolic blood pressure), and glucose regulation (fasting serum glucose and Hb1Ac). The four factors accounted for 84% of the total variances, and variances explained by each factor were not substantially different. There was no inter-correlation between the four factors. Subgroup analyses by sex and by race (Caucasian vs. African American) yielded the same four-factor structure.

CONCLUSION

The factor structure of MetS in obese individuals with BED is not different from those found in normative population studies. This factor structure may be applicable to the diverse population.

Association of the apolipoprotein b/apolipoprotein a-I ratio, metabolic syndrome components, total cholesterol, and low-density lipoprotein cholesterol with insulin resistance in the population of georgia

The study was designed to assess the association between insulin resistance (IR) and apolipoprotein B/apolipoprotein A-I ratio (ApoB/ApoA-I ratio), metabolic syndrome (MetS) components, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) in the nondiabetic population of Georgia. The subjects were 1522 Georgians of Caucasian origin (mean age = 45 years, 653 women) without diabetes who had visited the clinics for a related health checkup between 2012 and 2013. IR was calculated using the computer homeostasis model assessment (HOMA2-IR) and was defined as the upper quartile. MetS was diagnosed using the updated ATP-III definition of the metabolic syndrome. Logistic and multiple regression models were used to estimate the association between IR and other components. IR was positively correlated with age, ApoB, ApoB/ApoA-I ratio, MetS components (excluding high-density lipoprotein cholesterol-HDL-C), LDL-C, fasting insulin, and TC and negatively correlated with HDL-C and ApoA-I in both sexes (all P < 0.001). In the logistic regression models, gender, age, ApoB/ApoA-I ratio, diastolic pressure, HDL-C, LDL-C, fasting glucose, and triglycerides were the covariates significantly associated with IR (OR: 8.64, 1.03, 17.95, 1.06, 0.13, 1.17, 3.75, and 2.29, resp.; all P < 0.05). Multiple regression models demonstrated that these components (except for HDL-C) made an independent contribution to the prediction of HOMA2 (all P < 0.05).

Serum fibroblast growth factor 21 levels are correlated with the severity of diabetic retinopathy

The aim of the study was to assess serum fibroblast growth factor 21 (FGF21) concentrations in Chinese type 2 diabetic patients with and without retinopathy and to assess the association between FGF21 and the severity of retinopathy. 117 diabetic patients were compared with 68 healthy controls. Fasting blood glucose, serum total cholesterol, serum triglycerides, serum insulin, and serum FGF21 levels were estimated. FGF21 concentrations in the patients were significantly higher than those in control. In the patient group there was a significant positive correlation between FGF21, insulin level, and homeostasis model assessment index. Serum FGF21 concentrations in patients with proliferative diabetic retinopathy or nonproliferative diabetic retinopathy were significantly higher than those in patients without diabetic retinopathy. When the presence of diabetes was defined as the final variable in the conditional logistic regression model with the FGF21 concentration as the continuous variable, FGF21 was significantly involved in the model. This study shows that the increase in serum concentration of FGF21 was associated with the severity of diabetic retinopathy and suggests that FGF21 may play a role in the pathogenesis of diabetic retinopathy and its degree.

Identification of cardiovascular risk components in urban Chinese with metabolic syndrome and application to coronary heart disease prediction: a longitudinal study

Background

Metabolic syndrome (MetS) is proposed as a predictor for cardiovascular disease (CVD). It involves the mechanisms of insulin resistance, obesity, inflammation process of atherosclerosis, and their complex relationship in the metabolic network. Therefore, more cardiovascular risk-related biomarkers within this network should be considered as components of MetS in order to improve the prediction of CVD.

Methods

Factor analysis was performed in 5311 (4574 males and 737 females) Han Chinese subjects with MetS to extract CVD-related factors with specific clinical significance from 16 biomarkers tested in routine health check-up. Logistic regression model, based on an extreme case-control design with 445 coronary heart disease (CHD) patients and 890 controls, was performed to evaluate the extracted factors used to identify CHD. Then, Cox model, based on a cohort design with 1923 subjects followed up for 5 years, was conducted to validate their predictive effects. Finally, a synthetic predictor (SP) was created by weighting each factor with their risks for CHD to develop a risk matrix to predicting CHD.

Results

Eight factors were obtained from both males and females with a similar pattern. The AUC to classify CHD under the extreme case-control suggested that SP might serve as a useful tool in identifying CHD with 0.994 (95%CI 0.984-0.998) for males and 0.998 (95%CI 0.982-1.000) for females respectively. In the cohort study, the AUC to predict CHD was 0.871 (95%CI 0.851-0.889) for males and 0.899 (95%CI 0.873-0.921) for females, highlighting that SP was a powerful predictor for CHD. The SP-based 5-year CHD risk matrix provided as convenient tool for CHD risk appraisal.

Conclusions

Eight factors were extracted from sixteen biomarkers in subjects with MetS and the SP adds to new insights into studies of prediction of CHD risk using data from routine health check-up.

Fasting insulin concentrations and incidence of hypertension, stroke, and coronary heart disease: a meta-analysis of prospective cohort studies

BACKGROUND

Insulin resistance is a precursor of numerous chronic diseases, including cardiovascular disease (CVD). The fasting insulin concentration is considered a reasonable surrogate of insulin resistance, especially among nondiabetic individuals.

OBJECTIVE

We aimed to quantitatively summarize the literature on the association of fasting insulin concentrations with risk of hypertension, stroke, and coronary heart disease (CHD) by conducting a meta-analysis of prospective cohort studies.

DESIGN

Eligible studies were identified by searching PubMed and EMBASE through January 2013. Additional information was retrieved through Google Scholar or a hand review of the reference lists from relevant articles. Prospective cohort studies that reported RRs and corresponding 95% CIs for the association of interest were identified. Data were extracted independently by 2 investigators, and the weighted RRs and 95% CIs for the associations were obtained by using a random-effects model.

RESULTS

Of the 22 identified studies, 10 reported results on hypertension (36,617 individuals and 4491 cases), 7 on stroke (27,887 individuals and 1550 cases), and 9 on CHD (22,379 individuals and 1986 cases). Comparison of the highest with the lowest quantile of fasting insulin concentrations showed a pooled RR (95% CI) of 1.63 (1.35, 1.97) for hypertension, 1.18 (0.87, 1.60) for stroke, and 1.50 (1.28, 1.77) for CHD. Each 50-pmol/L increment in fasting insulin was associated with a 25% increase in risk of hypertension [RR: 1.25 (1.14, 1.36)] and a 16% increase in risk of CHD [RR: 1.16 (1.10, 1.22)] but was not associated with risk of stroke [RR: 0.999 (0.99, 1.01)].

CONCLUSIONS

A higher fasting insulin concentration or hyperinsulinemia was significantly associated with an increased risk of hypertension and CHD but not stroke. This meta-analysis suggests that early fasting insulin ascertainment in the general population may help clinicians identify those who are potentially at high risk of CVD.

Clusters of AMI risk factors and their association with left ventricular hypertrophy: a population-based study within the Skaraborg Project, Sweden

OBJECTIVES

Risk factors for acute myocardial infarction (AMI) are known to cluster and to be differently distributed in men and women. The aim of this study was to sex-specifically explore clusters of acknowledged AMI risk factors by factor analysis, and to study whether such clusters are associated with left ventricular hypertrophy (LVH), used as a subclinical measure of CHD.

METHODS

In 2001-2005, 2328 subjects (30-74 years) were randomly selected from two municipalities in Sweden (participation-rate 76%) and were assessed with regard to cardiovascular risk factors; 852 participants also had an echocardiographic examination performed.

RESULTS

Factor analysis identified three identical factors in men and women. WHR, HOMA-ir, systolic blood pressure, and ApoB/ApoA1 loaded significantly on the principal "metabolic factor", leisure-time physical activity and self-rated health loaded significantly on the "vitality factor", and smoking and alcohol consumption loaded significantly on the "addiction factor". The metabolic factor was associated with LVH in both men (P<0.001) and women (P<0.001), whereas the addiction factor was associated with LVH solely in men (P=0.002).

CONCLUSIONS

The consistent pattern in the clustering of acknowledged AMI risk factors suggests common underlying mechanisms in both men and women. However, whereas the metabolic factor was paramount in both men and women in the association with LVH, the addiction factor had an impact solely in men. As LVH often precedes AMI, a deeper understanding of risk factors for LVH, including consideration of the supposed sex differences, can be useful in order to explore prevention strategies for AMI.

Mifepristone reduces insulin resistance in patient volunteers with adrenal incidentalomas that secrete low levels of cortisol: a pilot study

Background

Incidental adrenal masses are commonly detected during imaging for other pathologies. 10% of the elderly population has an ‘adrenal incidentaloma’, up to 20% of these show low-grade autonomous cortisol secretion and 60% of patients with autonomous cortisol secretion have insulin resistance. Cortisol excess is known to cause insulin resistance, an independent cardiovascular risk marker, however in patients with adrenal incidentalomas it is unknown whether their insulin resistance is secondary to the excess cortisol and therefore potentially reversible. In a proof of concept study we examined the short-term effects of glucocorticoid receptor (GR) antagonism in patients with an adrenal incidentaloma to determine whether their insulin resistance was reversible.

Methodology/Principal Findings

In a prospective open-label pilot study, six individuals with adrenal incidentalomas and autonomous cortisol secretion were treated with mifepristone (a GR antagonist) 200 mg twice daily and studied for 4 weeks on a Clinical Research Facility. Insulin resistance at four weeks was assessed by insulin resistance indices, lnHOMA-IR and lnMatsuda, and AUC insulin during a 2-hour glucose tolerance test. Biochemical evidence of GR blockade was shown in all individuals and across the group there was a significant reduction in insulin resistance: lnHOMA-IR (1.0vs0.6; p = 0.03), lnHOMA-%beta (4.8vs4.3; p = 0.03) and lnMatsuda (1.2vs1.6; p = 0.03). Five out of six individuals showed a reduction in insulin AUC >7237 pmol/l.min, and in two patients this showed a clinically significant cardiovascular benefit (as defined by the Helsinki heart study).

Conclusions

Short-term GR antagonism is sufficient to reduce insulin resistance in some individuals with adrenal incidentalomas and mild cortisol excess. Further assessment is required to assess if the responses may be used to stratify therapy as adrenal incidentalomas may be a common remediable cause of increased cardiovascular risk.

Trial Registration

ClinicalTrials.gov NCT00721201

Insulin resistance and adipokines serum levels in a caucasian cohort of hiv-positive patients undergoing antiretroviral therapy: a cross sectional study

BACKGROUND

Insulin resistance is frequent in human immunodeficiency virus (HIV) infection and may be related to antiretroviral therapy. Cytokines secreted by adipose tissue (adipokines) are linked to insulin sensitivity. The present study is aimed to assess the prevalence of insulin resistance (IR) and its association with several adipokines, in a non-diabetic Romanian cohort of men and women with HIV-1 infection, undergoing combination antiretroviral therapy (cART).

METHODS

A cross-sectional study was conducted in an unselected sample of 89 HIV-1-positive, non-diabetic patients undergoing stable cART for at least 6 months. Metabolic parameters were measured, including fasting plasma insulin, and circulating adiponectin, leptin, resistin, tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) levels. Insulin resistance was estimated by measuring the Quantitative Insulin Sensitivity Check Index (QUICKI), using a cut-off value of 0.33. A linear regression model was fitted to QUICKI to test the association of IR and adipokines levels.

RESULTS

A total of 89 patients (aged 18-65, median: 28 years) including 51 men (57.3%) and 38 women (42.7%) were included in the study. Fifty nine patients (66.3%) were diagnosed with IR based on QUICKI values lower than the cut-off point. IR prevalence was 72.5% in men and 57.6% in women. The presence of the IR was not influenced by either the time of the HIV diagnosis or by the duration of cART. Decreased adiponectin and increased serum triglycerides were associated with increased IR in men (R=0.43, p=0.007). Hyperleptinemia in women was demonstrated to be associated with the presence of IR (R=0.33, p=0.03).

CONCLUSIONS

Given the significant prevalence of the IR in our young non-diabetic cohort with HIV infection undergoing antiretroviral therapy reported in our study and the consecutive risk of diabetes and cardiovascular events, we suggest that the IR management should be a central component of HIV-infection therapeutic strategy. As adipokines play major roles in regulating glucose homeostasis with levels varying according to the sex, we suggest that further studies investigating adipokines should base their analyses on gender differences.

The IGF-1 receptor and regulation of nitric oxide bioavailability and insulin signalling in the endothelium

The insulin-like growth factor-1 receptor (IGF-1R), like the insulin receptor (IR), plays a significant role in determining bioavailability of the critical signalling molecule nitric oxide (NO) and hence, modulates endothelial cell function, particularly in response to stimulation with insulin. In particular, the ability of the IGF-1R to form hybrid receptors with the IR appears to be highly significant in determining the sensitivity of the endothelial cell to insulin. This review will examine the structure of the IGF-1R and how this, with particular reference to the ability of the IGF-1R and the IR to form hybrid receptors, may have an effect both on endothelial cell function and the development of cardiovascular disease.

Cardiovascular changes in animal models of metabolic syndrome

Metabolic syndrome has been defined as a group of risk factors that directly contribute to the development of cardiovascular disease and/or type 2 diabetes. Insulin resistance seems to have a fundamental role in the genesis of this syndrome. Over the past years to the present day, basic and translational research has used small animal models to explore the pathophysiology of metabolic syndrome and to develop novel therapies that might slow the progression of this prevalent condition. In this paper we discuss the animal models used for the study of metabolic syndrome, with particular focus on cardiovascular changes, since they are the main cause of death associated with the condition in humans.

Prevalence of the metabolic syndrome in the Yan-an region of northwest China

OBJECTIVES

To evaluate the prevalence of the metabolic syndrome in a sample population from northwest China, and to determine the optimal cut-off point for waist circumference for diagnosing the metabolic syndrome in this population.

METHODS

A total of 1290 residents of the Yan-an region of China completed a cross-sectional survey, physical examination and laboratory tests. The International Diabetes Federation (IDF), Chinese Diabetes Society (CDS), and the National Cholesterol Education Program Adults Treatment Panel-III (NCEP-ATPIII) criteria were used to assess the prevalence of the metabolic syndrome and its relationship with age and gender.

RESULTS

According to the NCEP-ATPIII, CDS and IDF diagnostic criteria, the prevalence of the metabolic syndrome was 15.8%, 20.4% and 26.4%, respectively. The optimal cut-off point for waist circumference was ≥ 86.5 cm for men and ≥ 80.5 cm for women.

CONCLUSIONS

The prevalence of the metabolic syndrome in the Yan-an region was significantly higher than that in other regions of China, and participants with the metabolic syndrome were much younger than those in other Chinese regions.

Cell-specific insulin resistance: implications for atherosclerosis

Insulin resistance is increasingly acknowledged as an independent risk factor for cardiovascular disease. Despite this, our understanding of the cellular and molecular mechanisms that might account for this relationship remain incompletely understood. A key challenge has been in distinguishing between a 'whole-body' milieu of inflammation and oxidative stress from the ramifications of cell-specific resistance to insulin. Transgenic models have now begun to explore the cellular influences of insulin resistance on vascular biology, with novel implications for atherosclerosis across a range of cells including endothelial cells, endothelial progenitor cells, vascular smooth muscle cells, macrophages and fibroblasts. Emerging data from these models have also begun to challenge conventional dogma. In particular, the findings across various cell types are disparate with some even implying a protective influence on vascular biology. We now review these data, highlighting recent advances in our understanding of cellular resistance to insulin as well as those areas where there remains a paucity of data.

Factor structure underlying components of allostatic load

Allostatic load is a commonly used metric of health risk based on the hypothesis that recurrent exposure to environmental demands (e.g., stress) engenders a progressive dysregulation of multiple physiological systems. Prominent indicators of response to environmental challenges, such as stress-related hormones, sympatho-vagal balance, or inflammatory cytokines, comprise primary allostatic mediators. Secondary mediators reflect ensuing biological alterations that accumulate over time and confer risk for clinical disease but overlap substantially with a second metric of health risk, the metabolic syndrome. Whether allostatic load mediators covary and thus warrant treatment as a unitary construct remains to be established and, in particular, the relation of allostatic load parameters to the metabolic syndrome requires elucidation. Here, we employ confirmatory factor analysis to test: 1) whether a single common factor underlies variation in physiological systems associated with allostatic load; and 2) whether allostatic load parameters continue to load on a single common factor if a second factor representing the metabolic syndrome is also modeled. Participants were 645 adults from Allegheny County, PA (30–54 years old, 82% non-Hispanic white, 52% female) who were free of confounding medications. Model fitting supported a single, second-order factor underlying variance in the allostatic load components available in this study (metabolic, inflammatory and vagal measures). Further, this common factor reflecting covariation among allostatic load components persisted when a latent factor representing metabolic syndrome facets was conjointly modeled. Overall, this study provides novel evidence that the modeled allostatic load components do share common variance as hypothesized. Moreover, the common variance suggests the existence of statistical coherence above and beyond that attributable to the metabolic syndrome.

Filter paper blood spot enzyme linked immunoassay for insulin and application in the evaluation of determinants of child insulin resistance

Background

In large-scale epidemiology, bloodspot sampling by fingerstick onto filter paper has many advantages, including ease and low costs of collection, processing and transport. We describe the development of an enzyme-linked immunoassay (ELISA) for quantifying insulin from dried blood spots and demonstrate its application in a large trial.

Methods

We adapted an existing commercial kit (Mercodia Human Insulin ELISA, 10-1113-01) to quantify insulin from two 3-mm diameter discs (≈6 µL of blood) punched from whole blood standards and from trial samples. Paediatricians collected dried blood spots in a follow-up of 13,879 fasted children aged 11.5 years (interquartile range 11.3–11.8 years) from 31 trial sites across Belarus. We quantified bloodspot insulin levels and examined their distribution by demography and anthropometry.

Results

Mean intra-assay (n = 157) coefficients of variation were 15% and 6% for ‘low’ (6.7 mU/L) and ‘high’ (23.1 mU/L) values, respectively; the respective inter-assay values (n = 33) were 23% and 11%. The intraclass correlation coefficient between 50 paired whole bloodspot versus serum samples, collected simultaneously, was 0.90 (95% confidence interval 0.85 to 0.95). Bloodspot insulin was stable for at least 31 months at −80°C, for one week at +30°C and following four freeze-thaw cycles. Paediatricians collected a median of 8 blood spots from 13,487 (97%) children. The geometric mean insulin (log standard deviation) concentrations amongst 12,812 children were 3.0 mU/L (1.1) in boys and 4.0 mU/L (1.0) in girls and were positively associated with pubertal stage, measures of central and peripheral adiposity, height and fasting glucose.

Conclusions

Our simple and convenient bloodspot assay is suitable for the measurement of insulin in very small volumes of blood collected on filter paper cards and can be applied to large-scale epidemiology studies of the early-life determinants of circulating insulin.

Ambulatory blood pressure and the metabolic syndrome in normotensive and untreated hypertensive men

BACKGROUND

Components of the metabolic syndrome are typically intercorrelated in epidemiologic studies and, when combined, predict type 2 diabetes and cardiovascular diseases. However, it remains unclear whether a single construct underlies the various components and which of the components are most closely associated with the underlying syndrome. Here, we use our confirmatory factor analytic model of the metabolic syndrome to examine the extent to which measures of ambulatory blood pressure, reflecting blood pressure variability throughout the day and night, may strengthen the association between blood pressure and the other components of the syndrome.

METHODS

Participants were a community sample of 358 men (248 with hypertension), ages 40-70, not receiving antihypertensive medications. Confirmatory factor analysis was employed to examine model fit and the strength of association between clinic and ambulatory blood pressure and the metabolic syndrome.

RESULTS

The blood pressure factor loaded significantly on the underlying metabolic syndrome but the strength of association was not as great (loading = 0.34, p < 0.01) as those observed for the obesity, insulin resistance and lipid factors. The factor loadings for the ambulatory measures (awake loading = 0.19; sleep loading = 0.16, p values < 0.01) were significant but smaller in magnitude than the loadings for clinic blood pressure.

CONCLUSIONS

Both clinic and ambulatory measures of blood pressure are significantly associated with the underlying metabolic syndrome using confirmatory factor analytic methods. However, the strength of association appears greater for the clinic measures relative to the ambulatory measures in this study.

Evidence for fetal programming of obesity with a focus on putative mechanisms

Obesity is associated with insulin resistance, the metabolic syndrome (a clustering of three or more of increased waist circumference, blood pressure, fasting glucose and fasting plasma triacylglycerol levels and reduced HDL levels), and a marked increase in the risk of type 2 diabetes and CHD. The impact of obesity differs between individuals, particularly between men and women and between ethnic groups. For example, in South Asians, although overall obesity is less prevalent, central obesity and the metabolic syndrome are more prevalent than in Europeans and this pattern is associated with the development of type 2 diabetes and CHD at an earlier age. It is important to examine individual risk factors contributing to obesity because they may have a different impact in population subgroups. Many factors contribute to the aetiology of obesity and there is increasing evidence to suggest that altered early development is one such factor and is associated with abnormal fat accumulation, the metabolic syndrome and type 2 diabetes in later life. The present review presents this evidence and discusses some of the mechanisms that may be involved in the pathogenesis of the programming of obesity.