Insulin metabolism markers are predictors of subclinical atherosclerosis among overweight and obese children and adolescents

Fasting glucose: a cardiometabolic indicator for subclinical atherosclerosis on excess weight adolescents

OBJECTIVE

To build a model based on cardiometabolic indicators that allow the identification of overweight adolescents at higher risk of subclinical atherosclerotic disease (SAD).

METHODS

Cross-sectional study involving 161 adolescents with a body mass index ≥ +1 z-Score, aged 10 to 19 years. Carotid intima-media complex thickness (IMT) was evaluated using ultrasound to assess subclinical atherosclerotic disease. Cardiometabolic indicators evaluated included nutritional status, central adiposity, blood pressure, lipidic profile, glycemic profile, as well as age and sex. Data was presented using measures of central tendency and dispersion, as well as absolute and relative frequency. The relationship between IMT measurement (outcome variable) and other variables (independent variables) was assessed using Pearson or Spearman correlation, followed by multiple regression modeling with Gamma distribution to analyze predictors of IMT. Statistical analysis was performed using SPSS and R software, considering a significance level of 5 %.

RESULTS

It was observed that 23.7 % had Carotid thickening, and the prevalence of abnormal fasting glucose was the lowest. Age and fasting glucose were identified as predictors of IMT increase, with IMT decreasing with age by approximately 1 % per year and increasing with glucose by around 0.24 % per mg/dL.

CONCLUSION

The adolescent at higher risk is younger with higher fasting glycemia levels.

Early insulin resistance in normoglycemic low-risk individuals is associated with subclinical atherosclerosis

BACKGROUND

Elevated glycated hemoglobin (HbA1c) is associated with a higher burden of subclinical atherosclerosis (SA). However, the association with SA of earlier insulin resistance markers is poorly understood. The study assessed the association between the homeostatic model assessment of insulin resistance index (HOMA-IR) and SA in addition to the effect of cardiovascular risk factors (CVRFs) in individuals with normal HbA1c.

METHODS

A cohort of 3,741 middle-aged individuals from the Progression of Early Subclinical Atherosclerosis (PESA) study with basal HbA1c < 6.0% (< 42 mmol/mol) and no known CV disease underwent extensive imaging (multiterritorial vascular ultrasound and coronary artery calcium score, CACS) to assess the presence, burden, and extent of SA.

RESULTS

Individuals with higher HOMA-IR values had higher rates of CVRFs. HOMA-IR showed a direct association with the multiterritorial extent of SA and CACS (p < 0.001) and with global plaque volume measured by 3-dimensional vascular ultrasound (p < 0.001). After adjusting for key CVRFs and HbA1c, HOMA-IR values ≥ 3 were associated with both the multiterritorial extent of SA (odds ratio 1.41; 95%CI: 1.01 to 1.95, p = 0.041) and CACS > 0 (odds ratio 1.74; 95%CI: 1.20 to 2.54, p = 0.004), as compared with the HOMA-IR < 2 (the reference HOMA-IR category). In a stratified analysis, this association remained significant in individuals with a low-to-moderate SCORE2 risk estimate (75.6% of the cohort) but not in high-risk individuals.

CONCLUSIONS

The use of HOMA-IR identified low-risk individuals with a higher burden of SA, after adjusting for the effects of key traditional CVRFs and HbA1c. HOMA-IR is a simple measure that could facilitate earlier implementation of primary CV prevention strategies in clinical practice.

The association of long-term calcium and dairy products intake in adolescence with carotid intima media thickness and metabolic syndrome in early adulthood: Tehran Lipid and Glucose Study

BACKGROUND

Calcium could impact on vascular functions and structures and cause atherosclerosis. Thus, we aimed to examine the association of long-term calcium and dairy products intake in adolescence with cIMT and MetS in early adulthood.

METHODS

We considered 217 adolescents aged 12-18 years in the frame work of the Tehran Lipid and Glucose Study (2006-2009) and follow-up them to early adulthood (2015-2017). The valid food frequency questionnaire was used to assess dietary intake. Ultrasound examination was used to measure common carotid artery. The joint interim statement and cook et al. criteria were used for adults and adolescents to consider MetS, respectively.

RESULTS

Adolescents' average calcium intake from dairy and non-dairy sources were 395 mg/d and 1088 mg/d, respectively while adults had 212 mg/d and 1191 mg/d. In addition, the mean of cIMT in adults was 0.54 mm. There was no relationship of non-dairy (β: - 0.03; P = 0.804), and total calcium (β: - 0.001; P = 0.591) intake with cIMT and TG. None of the dairy products had link with cIMT, MetS and its components, except cream with cIMT after full adjustment of potential confounders (β: 0.245; P = 0.009). Also, we found that the intake of non-dairy products could increase DBP after controlling for potential confounders (β: 0.365; P = 0.012). Adolescence with higher quartiles of total calcium intake had no odds ratio of MetS in early adulthood (β: 2.05, P = 0.371).

CONCLUSIONS

Adolescence calcium and dairy products intake, with the exception of cream did not increase early adulthood cIMT and MetS and its components.

Comparison of novel markers of metabolic complications and cardiovascular risk factors between obese non-diabetic and obese type 1 diabetic children and young adults

Introduction

For the past years, the prevalence of obesity is growing in the general population of children, as well as among diabetic patients, resulting in increased risk of cardiovascular complications. Type 1 diabetes mellitus (T1DM) is one of the most common chronic diseases in children and young adults, leading to decreased life quality and lifespan, with obesity being recognized recently as a major contributing factor to these health problems. The objective of this study was to analyze and compare the selected novel markers for metabolic complications of obesity and vascular risk factors between obese non-diabetic and obese T1DM children and young adults.

Methods

One hundred four subjects, aged between 10 and 24 years (31 with T1DM and excessive body weight, 41 with obesity without diabetes, and 32 with T1DM and normal weight), and 32 matched lean controls were included in the study. Clinical characteristics, blood pressure measurements, daily requirement for insulin, HbA1c%, plasma lipids, fetuin-A, E-selectin, and osteoprotegerin levels were compared with respect to body mass index (BMI), body mass index standard deviation score (BMI-SDS), and carotid intima-media thickness (cIMT) of common carotid arteries.

Results

Patients with T1DM and excessive body weight compared to non-diabetic obese subjects had similar values of systolic blood pressure (125.6 ± 8.2 vs. 127.3 ± 12.9 mmHg, p = 0.515), diastolic blood pressure (78.19 ± 7.03 vs. 78.02 ± 8.01 mmHg, p = 0.918), cholesterol (175.26 ± 34.1 vs. 163.51 ± 26.08 mg/dl, p = 0.102), LDL (108.03 ± 32.55 vs. 112.22 ± 26.36 mg/dl, p = 0.548), and triglyceride levels (118.19 ± 71.20 vs. 117 ± 55.80 mg/dl, p = 0.937); all values were found to be higher compared to non-obese T1DM and healthy controls. HbA1c level and insulin resistance indices were significantly worse in T1DM obese vs. T1DM non-obese patients. Fetuin-A levels were higher among obese non-diabetic patients (p = 0.01), and E-selectin and osteoprotegerin levels were similar in both groups with obesity, but higher than in the reference group. There were no statistical differences in cIMT with T1DM with normal weight, excessive weight, and non-diabetic obese children; however, the cIMT value was higher compared to the reference group.

Discussion

Novel markers of metabolic complications of obesity are similar between obese T1DM and non-diabetic subjects. Obesity in patients with T1DM results in worse metabolic control, insulin resistance, and increased risk for vascular complications.

Association of the triglyceride-glucose index and vascular target organ damage in a Beijing community-based population

Objective

We aimed to explore the association between the triglyceride-glucose (TyG) index, a marker of insulin resistance (IR), and vascular target organ damage (TOD) in a Beijing community-based population, China.

Methods

A total of 6,015 participants from an atherosclerosis cohort survey performed in the Shijingshan District in Beijing, China were included in our analysis. Vascular TOD, such as carotid-femoral pulse wave velocity (cfPWV), brachial-ankle pulse wave velocity (baPWV), and the urine albumin-to-creatinine ratio (UACR) were all evaluated.

Results

The overall mean age of all the participants was 62.35 years, 3,951 (65.69%) were female, and mean TyG index was 8.81. In univariable regression analyzes, an increased TyG index was associated with higher cfPWV, baPWV, lnUACR, and higher risk of cfPWV ≥ 10 m/s, baPWV ≥ 1,800 cm/s, and UACR ≥ 30 mg/g, respectively. Multivariable regression analyzes showed subjects with the TyG index in top tertile had a significant increase in cfPWV (β = 0.29 m/s; 95% confidence interval [95% CI] 0.19-0.40; p fortrend < 0.001), baPWV (β = 69.28 cm/s; 95% CI 50.97-87.59; p fortrend < 0.001), lnUACR (β = 0.23; 95% CI 0.13-0.34; p fortrend < 0.001), and had a higher risk of cfPWV ≥ 10 m/s (odds ratio [OR] = 1.47; 95% CI 1.17-1.85; p fortrend < 0.001), baPWV ≥ 1,800 cm/s (OR = 1.79; 95% CI 1.48-2.17; p fortrend < 0.001), and UACR ≥ 30 mg/g (OR = 1.71; 95% CI 1.30-2.24; p fortrend < 0.001) after fully adjusting for age, sex, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), estimated glomerular filtration rate (eGFR), self-reported coronary heart disease (CHD) and stroke, antihypertensive drugs, hypoglycemic drugs, and lipid-lowering drugs. Consistent conclusions were obtained in the subgroups without hypoglycemic and lipid-lowering medications or aged younger than 65 years old.

Conclusions

The TyG index was positively associated with artery stiffness and nephric microvascular damage in a Beijing community-based population in China. This result provides evidence that the TyG index may serve as a simple and effective indicator to reflect vascular TOD.

Direct and indirect effects of obesity on progression of carotid arterial injury in youth

OBJECTIVE

Increased carotid intima-media thickness (cIMT) is associated with cardiovascular (CV) events in adults and with elevated CV risk factors in youth. The aim of this study was to determine whether obesity has an direct or indirect association with cIMT.

METHODS

Structural equation modeling was used to elucidate pathways for obesity to change cIMT. Complete data were collected twice on 294 participants (mean age 17.5 years, 16% with type 2 diabetes). Latent baseline and follow-up cIMT, BMI, and CV risk factors were analyzed with SAS 9.4. Model fit was assessed.

RESULTS

There were increases in BMI, mean arterial pressure (MAP), low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, C-reactive protein, and glucose and a decrease in insulin and glycosylated hemoglobin over 5 years (all p < 0.05). Only bulb (0.031 mm) and internal (0.027 mm) cIMT increased (all p < 0.001). Significant direct effects on cIMT change were baseline MAP (β 0.23), BMI z score (β 0.16), change in glucose (β 0.37), and age (β 0.37; all p < 0.05). Change in MAP showed a trend (β 0.14, p = 0.10). BMI also had a significant indirect effect (β 0.17), whereas non-HDL demonstrated no significant effect.

CONCLUSIONS

Baseline adiposity drives increasing blood pressure and glucose in high-risk youth leading to accelerated accumulation of carotid arterial injury. Prevention of acquisition of obesity in youth is critical in slowing development of CV disease.

Childhood traffic-related air pollution and adverse changes in subclinical atherosclerosis measures from childhood to adulthood

BACKGROUND

Chronic exposure to air pollutants is associated with increased risk of cardiovascular disease (CVD) among adults. However, little is known about how air pollution may affect the development of subclinical atherosclerosis in younger populations. Carotid artery intima-media thickness (CIMT) is a measure of subclinical atherosclerosis that provides insight into early CVD pathogenesis.

METHODS

In a pilot study of 70 participants from the Southern California Children's Health Study, we investigated CIMT progression from childhood to adulthood. Using carotid artery ultrasound images obtained at age 10 and follow-up images at age 21-22, we examined associations between childhood ambient and traffic-related air pollutants with changes in CIMT over time and attained adult CIMT using linear mixed-effects models adjusted for potential confounders. Average residential childhood exposures (i.e., birth to time of measurement at 10-11 years) were assigned for regional, ambient pollutants (ozone, nitrogen dioxide, particulate matter, interpolated from regulatory air monitoring data) and traffic-related nitrogen oxides (NO_x) by road class (modeled using the CALINE4 line source dispersion model). Traffic density was calculated within a 300-m residential buffer.

RESULTS

For each 1 standard deviation (SD) increase in childhood traffic-related total NO_x exposure, we observed greater yearly rate of change in CIMT from childhood to adulthood (β: 2.17 μm/yr, 95% CI: 0.78-3.56). Increases in annual rate of CIMT change from childhood to adulthood also were observed with freeway NO_x exposure (β: 2.24 μm/yr, 95% CI: 0.84-3.63) and traffic density (β: 2.11 μm/yr, 95% CI: 0.79-3.43). Traffic exposures were also related to increases in attained CIMT in early adulthood. No associations of CIMT change or attained level were observed with ambient pollutants.

CONCLUSIONS

Overall, we observed adverse changes in CIMT over time in relation to childhood traffic-related NO_x exposure and traffic density in our study population. While these results must be cautiously interpreted given the limited sample size, the observed associations of traffic measures with CIMT suggest a need for future studies to more fully explore this relationship.

LOX-1, the Common Therapeutic Target in Hypercholesterolemia: A New Perspective of Antiatherosclerotic Action of Aegeline

BACKGROUND

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is the major receptor for oxidized low-density lipoprotein (Ox-LDL) in the aorta of aged rats. Ox-LDL initiates LOX-1 activation in the endothelium of lipid-accumulating sites of both animal and human subjects of hypercholesterolemia. Targeting LOX-1 may provide a novel diagnostic strategy towards hypercholesterolemia and vascular diseases.

HYPOTHESIS

This study was planned to address whether aegeline (AG) could bind to LOX-1 with a higher affinity and modulate the uptake of Ox-LDL in hypercholesterolemia.

STUDY DESIGN

Thirty-six Wistar rats were divided into six groups. The pathology group rats were fed with high-cholesterol diet (HCD) for 45 days, and the treatment group rats were fed with HCD and aegeline/atorvastatin (AV) for the last 30 days. In vivo and in vitro experiments were carried out to assay the markers of atherosclerosis like Ox-LDL and LOX-1 levels. Histopathological examination was performed. Oil Red O staining was carried out in the IC-21 cell line. Docking studies were performed.

RESULTS

AG administration effectively brought down the lipid levels induced by HCD. The lowered levels of Ox-LDL and LOX-1 in AG-administered rats deem it to be a potent antihypercholesterolemic agent. Compared to AV, AG had a pronounced effect in downregulating the expression of lipids evidenced by Oil Red O staining. AG binds with LOX-1 at a higher affinity validated by docking.

CONCLUSION

This study validates AG to be an effective stratagem in bringing down the lipid stress induced by HCD and can be deemed as an antihypercholesterolemic agent.

The relation between circulating levels of vitamin D and parathyroid hormone in children and adolescents with overweight or obesity: Quest for a threshold

The level of serum 25-hydroxyvitamin D (25(OH)D) at which intact parathyroid hormone (iPTH) is maximally suppressed (suppression point) and below which PTH begins to rise (inflection point) has been used to define optimum 25(OH)D concentration. We aimed to study the association of circulating iPTH with 25(OH)D concentrations and to determine a 25(OH)D threshold associated with a significant iPTH suppression. This cross-sectional study was conducted on 198 boys and 180 girls, aged 6–13 years with BMI ≥ 1SD (WHO criteria) recruited from primary schools. Adjusted iPTH for BMI z-score, pubertal status, and dietary calcium was used. Nonlinear regression was used to model the relationship between 25(OH)D and iPTH and identify a suppression point for 25(OH)D at which iPTH reached a plateau. Piecewise regression analysis with a single knot for all possible values of 25(OH)D were fitted. Furthermore, 95% confidence intervals (95%CI) for those point had been calculated. The mean age (SD) of girls and boys was 9.1 (1.6) and 9.4 (1.7) years, respectively. Median 25(OH)D and iPTH were 13.8 ng/mL and 33.9 pg/mL in boys and 9.9 ng/mL and 47.8 ng/mL in girls, respectively. The equation in girls was: log-iPTH = 3.598+0.868 exp[(-0.190×25(OH)D. The point for near maximal suppression of iPTH by 25(OH)D for girls occurred at a 25(OH)D concentration of 20 ng/mL (95% CI: 7.1 to 32.2). No point of maximal suppression was found for boys. We also found a 25(OH)D threshold of 10 ng/mL (95% CI: 4.6 to 22.5) for girls (f: 9.8) by linear piecewise regression modeling of adjusted iPTH. No significant inflection point for boys was observed. In overweight/obese girls, when the concentration of 25(OH)D was higher than 20 ng/mL, an iPTH mean plateau level is reached, and when its concentrations approach 10 ng/mL, the slope of iPTH concentration has been accelerated.