Atherogenic dyslipidemia in children: evaluation of clinical, biochemical and genetic aspects

Anthropometric and Biochemical Correlations of Insulin Resistance in a Middle-Aged Maltese Caucasian Population

Background

Insulin resistance (IR) is associated with increased cardiovascular disease risk, and with increased all-cause, cardiovascular, and cancer mortality. A number of surrogate markers are used in clinical practice to diagnose IR. The aim of this study was to investigate the discriminatory power of a number of routinely available anthropometric and biochemical variables in predicting IR and to determine their optimal cutoffs.

Methods

We performed a cross-sectional study in a cohort of middle-aged individuals. We used receiver operator characteristics (ROC) analyses in order to determine the discriminatory power of parameters of interest in detecting IR, which was defined as homeostatic model assessment-insulin resistance ≥2.5.

Results

Both the lipid accumulation product (LAP) and visceral adiposity index (VAI) exhibited good discriminatory power to detect IR in both males and females. The optimal cutoffs were 42.5 and 1.44, respectively, in males and 36.2 and 1.41, respectively, in females. Serum triglycerides (TG) and waist circumference (WC) similarly demonstrated good discriminatory power in detecting IR in both sexes. The optimal cutoffs for serum TG and WC were 1.35 mmol/L and 96.5 cm, respectively, in men and 1.33 mmol/L and 82 cm, respectively, in women. On the other hand, systolic and diastolic blood pressure, liver transaminases, high-density lipoprotein cholesterol, serum uric acid, ferritin, waist-hip ratio, "A" body shape, thigh circumference, and weight-adjusted thigh circumference all had poor discriminatory power.

Conclusions

Our data show that LAP, VAI, TG, and WC all have good discriminatory power in detecting IR in both men and women. The optimal cutoffs for TG and WC were lower than those currently recommended in both sexes. Replication studies are required in different subpopulations and different ethnicities in order to be able to update the current cut points to ones which reflect the contemporary population as well as to evaluate their longitudinal relationship with longer-term cardiometabolic outcomes.

Cardiovascular prevention in childhood: a consensus document of the Italian Society of Cardiology Working Group on Congenital Heart Disease and Cardiovascular Prevention in Paediatric Age

Cardiovascular diseases (CVD) may be manifested from a very early age. Genetic and environmental (epigenetic) factors interact to affect development and give rise to an abnormal phenotypical expression of genetic information, although not eliciting changes in the nucleotide sequence of DNA. It has been scientifically proven that increased oxidative stress (OS) caused by disease (overweight, obesity, diabetes), nutritional imbalances, unhealthy lifestyles (smoking, alcohol, substance abuse) in the mother during pregnancy may induce placental dysfunction, intrauterine growth restriction, prematurity, low birth weight, postnatal adiposity rebound, metabolic alterations and consequent onset of traditional cardiovascular risk factors. OS represents the cornerstone in the onset of atherosclerosis and manifestation of CVD following an extended asymptomatic period. OS activates platelets and monocytes eliciting the release of pro-inflammatory, pro-atherogenic and pro-oxidising substances resulting in endothelial dysfunction, decrease in flow-mediated arterial dilatation and increase in carotid intima-media thickness. The prevention of CVD is defined as primordial (aimed at preventing risk factors development), primary (aimed at early identification and treatment of risk factors), secondary (aimed at reducing risk of future events in patients who have already manifested a cardiovascular event), and tertiary (aimed at limiting the complex outcome of disease). Atherosclerosis prevention should be implemented as early as possible. Appropriate screening should be carried out to identify children at high risk who are apparently healthy and implement measures including dietary and lifestyle changes, addition of nutritional supplements and, lastly, pharmacological treatment if risk profiles fail to normalise. Reinstating endothelial function during the reversible stage of atherosclerosis is crucial.

Elevated Serum Concentrations of Remnant Cholesterol Associate with Increased Carotid Intima-Media Thickness in Children and Adolescents

OBJECTIVE

To evaluate the relationship between remnant cholesterol and carotid intima-media thickness (cIMT), a surrogate marker for atherosclerosis, in children and adolescents.

STUDY DESIGN

Anthropometric, laboratory, liver, and carotid ultrasonographic data were obtained from 767 youths (594, overweight/obese; 173, normal weight). Fasting remnant cholesterol was calculated from the standard lipid profile. cIMT ≥0.56 mm (corresponding to the 90th percentile of values observed in normal-weight children) was chosen to define elevated cIMT. Logistic regression analysis was used to estimate the risk of elevated cIMT according to tertiles of remnant cholesterol levels.

RESULTS

In the entire cohort, the mean concentration of remnant cholesterol was 17.9 ± 10.3 mg/dL and mean cIMT value was 0.51 ± 0.8 mm. Remnant cholesterol significantly correlated with age, sex, body mass index, waist circumference, blood pressure, lipids, liver enzymes, and insulin resistance. cIMT value increased progressively with rising remnant cholesterol tertiles (P_{for trend} < .001). Compared with subjects in the lowest remnant cholesterol tertile, those in the middle and highest remnant cholesterol tertiles had a 2.3- and 2.4-fold increased risk of elevated cIMT, independently of age, sex, pubertal stage, body mass index, and apolipoprotein B (all P_adj ≤ .003). When the effects of overweight/obesity on the association between remnant cholesterol and cIMT were determined, normal-weight as well as overweight/obese subjects in the highest remnant cholesterol tertile had a 3.8- and 2.3-fold increased risk to have elevated cIMT compared with the respective study groups in the lowest tertile, after adjustment for conventional risk factors (P_adj = .038 and P_adj = .003, respectively).

CONCLUSIONS

In youths, elevated levels of remnant cholesterol might represent a marker of early atherosclerotic damage.

Associations between lipid profiles of adolescents and their mothers based on a nationwide health and nutrition survey in South Korea

OBJECTIVES

Dyslipidaemia is a metabolic disease influenced by environmental and genetic factors. Especially, family history related to genetic background is a strong risk factor of lipid abnormality. The aim of this study is to evaluate the association between the lipid profiles of adolescents and their mothers.

DESIGN

A cross-sectional study.

SETTING

The data were derived from the Korea National Health and Nutrition Examination Survey (IV-VI) between 2009 and 2015.

PARTICIPANTS

2884 adolescents aged 12-18 years and their mothers were included.

PRIMARY OUTCOME MEASURES

Outcome variables were adolescents' lipid levels. Mothers' lipid levels were the interesting variables. The lipid profiles included total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). We identified partial correlation coefficients (r) between the lipids. Multiple linear regressions were performed to identify the amount of change in adolescents' lipid levels for each unit increase of their mothers' lipids. The regression models included various clinical characteristics and health behavioural factors of both adolescents and mothers.

RESULTS

The mean levels of adolescents' lipids were 156.6, 83.6, 50.4 and 89.4 mg/dL, respectively for TC, TG, HDL-C and LDL-C. Positive correlations between lipid levels of adolescents and mothers were observed for TC, TG, HDL-C and LDL-C (r, 95% CI: 0.271, 0.236 to 0.304; 0.204, 0.169 to 0.239; 0.289, 0.255 to 0.322; and 0.286, 0.252 to 0.319). The adolescent TC level was increased by 0.23 mg/dL for each unit increase of the mother's TC (SE, 0.02; p<0.001). The beta coefficients were 0.16 (SE, 0.01), 0.24 (SE, 0.02) and 0.24 (SE, 0.02), respectively, in each model of TG, HDL-C and LDL-C (all p<0.001). The linear relationships were significant regardless of sex and mother's characteristics.

CONCLUSIONS

Mothers' lipid levels are associated with adolescents' lipids; therefore, they can serve as a reference for the screening of adolescent's dyslipidaemia.

Adiponectin is associated with cardio-metabolic traits in Mexican children

The adipocyte-derived adiponectin hormone bridges obesity and its cardio-metabolic complications. Genetic variants at the ADIPOQ locus, in ADIPOR1, and ADIPOR2 have been associated with adiponectin concentrations and cardio-metabolic complications in diverse ethnicities. However, no studies have examined these associations in Mexican children. We recruited 1 457 Mexican children from Mexico City. Six genetic variants in or near ADIPOQ (rs182052, rs2241766, rs266729, rs822393), ADIPOR1 (rs10920533), and ADIPOR2 (rs11061971) were genotyped. Associations between serum adiponectin, genetic variants, and cardio-metabolic traits were assessed using linear and logistic regressions adjusted for age, sex, and recruitment center. Serum adiponectin concentration was negatively associated with body mass index, waist to hip ratio, low-density lipoprotein cholesterol, total cholesterol, triglycerides, fasting glucose, fasting insulin, homeostatic model assessment of insulin resistance, dyslipidemia and overweight/obesity status (7.76 × 10⁻⁴⁰ ≤ p ≤ 3.00 × 10⁻³). No significant associations between genetic variants in ADIPOQ, ADIPOR1, and ADIPOR2 and serum adiponectin concentration were identified (all p ≥ 0.30). No significant associations between the six genetic variants and cardio-metabolic traits were observed after Bonferroni correction (all p < 6.9 × 10⁻⁴). Our study suggests strong associations between circulating adiponectin concentration and cardio-metabolic traits in Mexican children.

The Liver in Children With Metabolic Syndrome

Non-alcoholic fatty liver disease (NAFLD) is recognized as an emerging health risk in obese children and adolescents. NAFLD represents a wide spectrum of liver conditions, ranging from asymptomatic steatosis to steatohepatitis. The growing prevalence of fatty liver disease in children is associated with an increased risk of metabolic and cardiovascular complications. NAFLD is considered the hepatic manifestation of Metabolic Syndrome (MetS) and several lines of evidence have reported that children with NAFLD present one or more features of MetS. The pathogenetic mechanisms explaining the interrelationships between fatty liver disease and MetS are not clearly understood. Altough central obesity and insulin resistance seem to represent the core of the pathophysiology in both diseases, genetic susceptibility and enviromental triggers are emerging as crucial components promoting the development of NAFLD and MetS in children. In the present review we have identified and summarizied studies discussing current pathogenetic data of the association between NAFLD and MetS in children.

Associations of apolipoprotein B/apolipoprotein A-I ratio with pre-diabetes and diabetes risks: a cross-sectional study in Chinese adults

BACKGROUND

Apolipoprotein B/apolipoprotein A-I (ApoB/ApoA-I) ratio is a useful predictor of cardiovascular risk. However, the association between the ApoB/ApoA-I ratio and the risk of type 2 diabetes mellitus (T2DM) is still obscure.

AIMS

To investigate the associations between the ApoB/ApoA-I ratio and the risk of T2DM and pre-diabetes in a Chinese population, and to assess the role of gender in these associations.

METHODS

A stratified random sampling design was used in this cross-sectional study which included 264 men and 465 women with normal glucose tolerance (NGT), pre-diabetes or T2DM. Serum ApoB, ApoA-I and other lipid and glycaemic traits were measured. Pearson's partial correlation and multivariable logistic analysis were used to evaluate the associations between ApoB/ApoA-I ratio and the risk of T2DM and pre-diabetes.

RESULTS

The ApoB/ApoA-I ratios were significantly increased across the spectrum of NGT, pre-diabetes and T2DM. Women showed higher levels of ApoB/ApoA-I ratio and ApoB than men in the pre-diabetic and T2DM groups, but not in the NGT group. The ApoB/ApoA-I ratio was closely related with triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and other glycaemic traits. Moreover, in women, the risk of diabetes and pre-diabetes in the top and middle tertiles of the ApoB/ApoA-I ratio were 3.65-fold (95% CI 1.69 to 6.10) and 2.19-fold (95% CI 1.38 to 2.84) higher than in the bottom tertile, respectively, after adjusting for potential confounding factors. However, the associations disappeared in men after adjusting for other factors.

CONCLUSIONS

The ApoB/ApoA-I ratio showed positive associations with the risk of diabetes and pre-diabetes in Chinese women.

Dyslipidemia and cardiovascular changes in children

PURPOSE OF REVIEW

In this review, we firstly highlight the role of dyslipidemia as a trigger in the initiation and progression of endothelial dysfunction, considered the earliest atherosclerotic lesion and patent in children with risk factors.In this context, we also revise methods that reflect the impact of endothelial dysfunction not only on arterial stiffness but also on cardiovascular morphology, namely, the common carotid intima-media thickness and the ventricular geometry.

RECENT FINDINGS

In view of its atherogenic burden, the most widely studied lipoprotein has been low density lipoprotein cholesterol. However, the smaller, denser, low density lipoprotein cholesterol particles, the nonhigh density lipoprotein cholesterol fraction, appear to be more atherogenic and a more sensitive cardiovascular risk marker. Studies have shown that in children, atherogenic lipids have also been linked to cardiovascular morphological changes, such as the common carotid intima-media thickness and the ventricular geometry, both independent cardiovascular risk markers.

SUMMARY

In infancy, atherosclerosis is a preclinical disorder in which dyslipidemia plays a crucial role. Due to its impact on cardiovascular structures, potentially reversible during childhood, dyslipidemia ought to be managed aggressively to prevent further disease progression that will ultimately culminate in cardiac disease, a leading cause of mortality in adults.