Optimal Cut-off Points of Fasting and Post-Glucose Stimulus Surrogates of Insulin Resistance as Predictors of Metabolic Syndrome in Adolescents According to Several Definitions

The predictive value of combined insulin resistance and β-cell secretion in Yemeni school-aged children for type 2 diabetes mellitus

The present study aimed to determine the predictive power of the diabetic markers and metabolic syndrome factors in School-aged children for developing Type 2 DM. In this cross-sectional study, 1288 students aged 12-13 were recruited from public schools in the capital city of Sana'a. Anthropometric measurements and blood pressure were recorded and body mass index (BMI) was calculated. Fasting venous blood (5 ml) was collected for biochemical analysis including FBG, HbA1c, insulin, and lipid profile. Insulin resistance (HOMA-IR) and β-cell function (HOMA-β) were calculated. Our results showed that neither insulin, HOMA-IR nor HOMA-β individually were good predictors for Type 2 DM as assessed by the ROC curve with AUC < 0.75. However, the ROC curve of combined HOMA-IR and HOMA-β (Model 1) gave a superior AUC of 0.998 (p = 2.7 × 10-9) and predicted 140 (10.9%) children to develop Type 2 DM. This model picked up all impaired fasting glucose (IFG), 74% of metabolic glucose, and 71% of metabolic syndrome (MetS) groups. On the other hand, the ROC curve for metabolic syndrome (Model 2) gave an AUC of 0.751 (p = 0.003) and predicted a higher number of 416 (32.3%) children to develop prediabetes and Type 2 DM. This model picked up 75% of IFG, 71% of MetS, 82% of those having two factors of MetS, and 72% of obesity groups. Moreover, the 53 children common between the two models include 75% of IFG and 43% of MetS groups. Therefore, the combined HOMA-IR and HOMA-β model in children proved to be a good predictor for Type 2 DM development, whereas the MetS model predicts the development of prediabetes and Type 2 DM.

Sociodemographic inequalities in cardiovascular risk factors among adolescents from indigenous areas in Chiapas, Mexico

This study was aimed to determine the prevalence of cardiovascular risk factors among different sociodemographic groups of adolescents from indigenous communities in Chiapas, Mexico. A cross-sectional prevalence study was performed in urban and rural communities in the Tzotzil-Tzeltal and Selva regions of Chiapas. A sample of 253 adolescents was studied, of whom 48% were girls and 52% were boys. A descriptive analysis of quantitative variables was performed using measures of central tendency and dispersion. The prevalence of cardiovascular risk factors stratified by sex, geographical area, years of schooling, and ethnicity of the mothers was estimated. The prevalence of cardiovascular risk factors was analyzed in relation to the sociodemographic characteristics of the study population. Low HDL-c (51%) was the predominant cardiovascular risk factor. Girls had a higher prevalence of abdominal obesity, hypertriglyceridemia, and borderline total cholesterol than boys. High diastolic blood pressure was more prevalent in boys. Adolescents from urban areas had a higher prevalence of overweight/obesity and insulin resistance than adolescents from rural areas. The prevalence of overweight/obesity and abdominal obesity was higher in adolescents whose mothers had ≥ 7 years of schooling compared with adolescents with less educated mothers. Differences by maternal ethnicity also influenced the prevalence of insulin resistance. Among the main findings, this study associated sociodemographic and geographical inequalities with cardiovascular risk factors. Promoting a healthy lifestyle for this young population is absolutely necessary to prevent cardiovascular diseases in adulthood.

Height-Corrected Definition of Metabolic Syndrome Is a Simple and Effective Method for Identifying Insulin Resistance and Low-Grade Inflammation in Adolescents: Metabolic Syndrome in Adolescents

The purpose of this study was to evaluate the feasibility of the height-corrected definition of metabolic syndrome(MetS) in adolescents. A retrospective study was conducted on US adolescents aged 12 to 17 years. Waist-to-height ratio and blood pressure-to-height ratio were substituted for waist circumference and blood pressure when defining MetS in adolescents. The proportions of insulin resistance of adolescents with 1 (30.1%), 2 (50.7%), and ≥3 components (77.8%) of MetS were 2.578 (P < .001), 6.882 (P < .001), and 23.992 (P < .001) times than the proportion of adolescents without the component of MetS (14.2%). The proportions of low-grade inflammation of adolescents with 1 (3.4%), 2 (5.3%), and ≥3 components (14.4%) of MetS were 2.050 (P = .106), 3.699 (P = .005), and 10.664 (P < .001) times than the proportion of adolescents without the component of MetS (1.7%). This study demonstrates that height-corrected definition of MetS is a simple and accurate method for identifying insulin resistance and low-grade inflammation in adolescents.

Relationship between hematologic parameters related to systemic inflammation and insulin resistance-associated metabolic parameters in women with polycystic ovary syndrome

OBJECTIVE

The aim of the present study was to evaluate the associations between hematologic parameters related to systemic inflammation and insulin resistance-associated metabolic parameters in women with polycystic ovary syndrome (PCOS).

METHODS

Eighty-two women between the ages of 18 and 35 years who were diagnosed with PCOS were included in this study. A 2-hour 75-g oral glucose tolerance test (OGTT) was administered to all study participants; fasting and postprandial glucose and insulin levels were measured simultaneously during the 2-hour OGTT. Hematologic parameters were derived from a standard complete blood count and a differential count of fasting-state blood samples. The correlations between hematologic parameters and insulin resistance-associated clinical and metabolic parameters were evaluated using the Spearman rank correlation and partial correlation coefficients. Hematologic parameters related to systemic inflammation were compared between the two groups, categorized by the presence or absence of insulin resistance.

RESULTS

Significant differences in the absolute neutrophil count, absolute monocyte count, platelet count, and neutrophil-lymphocyte ratio were found between the insulin-resistant group and insulin-nonresistant group. Correlation analysis found that all hematological parameters, except for the platelet-lymphocyte ratio, were associated with at least one insulin resistance-associated metabolic parameter. However, these significant correlations between hematological and metabolic parameters were attenuated after controlling for the effects of other covariates using partial correlation analysis.

CONCLUSION

The association between hematologic parameters indicative of systemic inflammation and insulin resistance-associated metabolic parameters seems to be strongly influenced by other anthropometric covariates in women with PCOS.

Prevalence of metabolic syndrome in adolescents based on three diagnostic definitions: a cross-sectional study

Objective

There is no consensus as to the best criterion for the evaluation of metabolic syndrome (MS), impairing the estimation of its prevalence. This study aims to compare MS estimates using three recommended definitions for adolescents based on a cross-sectional study nested in the Consortium of Brazilian Birth Cohorts in São Luís, Maranhão.

Subjects and methods

A total of 2,515 adolescents aged between 18 and 19 years were evaluated. The criteria of International Diabetes Federation (IDF) and National Cholesterol Education Program Panel III (NCEP-ATP) modified by Cook and cols. (2003) and De Ferranti and cols. (2004) defined SM. To compare the estimates of MS prevalence, the chi-square, Fisher´s exact and Cohen´s Kappa index tests were used.

Results

Among the 2,064 participants evaluated in the final sample. The prevalence of MS ranged from 4.2% (95% CI: 3.3-5.1) to 10.2% (95% CI: 8.8-11.4). When comparing the estimates of MS prevalence in the total sample and by sex, a statistically significant difference was observed. The agreement between the criteria ranged from 0.42 (CI 95%: 0.35-0.49) to 0.55 (CI 95%: 0.48-0.62) in the total sample, 0.33 (CI 95%: 0.24-0.42) to 0.59 (95%CI: 0.47-0.71) among boys and 0.39 (95% CI: 0.26-0.52) to 0.54 (95% CI: 0.44-0.64) among girls.

Conclusion

Different criteria provide different estimates for the prevalence of MS in adolescents, reflecting the importance of establishing a consensus.

Cardiometabolic Risk is Positively Associated with Underreporting and Inversely Associated with Overreporting of Energy Intake Among European Adolescents: The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study

BACKGROUND

Dietary misreporting is the main limitation of dietary assessments and has been associated with BMI during youth. However there are no prior studies assessing misreporting and cardiometabolic risks (CMRs) in adolescence.

OBJECTIVES

To examine the associations between dietary misreporting and CMR factors in adolescents and to assess the potential bias in the association between CMR and energy intake (EI) driven by dietary misreporting.

METHODS

Two 24-hour dietary recalls were obtained from 1512 European adolescents (54.8% girls) aged 12.5-17.5 years. Physical activity was measured by accelerometry. Cut-offs suggested by Huang were applied to identify misreporters. Height, waist circumference (WC), the sum of 4 skinfold thicknesses, diastolic blood pressure (DBP), systolic blood pressure (SBP), and cardiorespiratory fitness (CRF) measurements were taken and serum triglycerides and total-/high-density lipoprotein cholesterol ratio were analyzed. A sex- and age-specific clustered CMR score (n = 364) was computed. Associations were investigated by multilevel regression analyses adjusting for age, sex, center, socioeconomic status, and physical activity.

RESULTS

Underreporting (24.8% adolescents) was significantly (P < 0.05) associated with a higher WC, waist-to-height ratio (WHeR), and sum of skinfold thickness, whereas overreporting (23.4% adolescents) was significantly associated with a lower WC, WHeR, sum of skinfold thickness, and SBP. Associations between CMR factors and EI were significantly affected by misreporting, considering various approaches. Significant, positive associations became inverse after adjusting for misreporting for WC and WHeR. The opposite was true for the sum of skinfold thickness, SBP, and CMR score. The associations between EI and DBP and CRF did not remain significant after adjusting for misreporting.

CONCLUSIONS

CMR factors differed among misreporting groups, and both abdominal and total fat mass indicators were more strongly associated with all forms of misreporting than was BMI. Moreover, misreporting seems to bias EI and CMR associations in adolescents. Therefore, energy misreporting should be taken into account when examining diet-CMR associations.

Gestational and childhood exposure to per- and polyfluoroalkyl substances and cardiometabolic risk at age 12 years

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) may adversely influence cardiometabolic risk. However, few studies have examined if the timing of early life PFAS exposure modifies their relation to cardiometabolic risk. We examined the influence of gestational and childhood PFAS exposure on adolescents' cardiometabolic risk.

METHODS

We quantified concentrations of four PFAS (perfluorooctanoate [PFOA], perfluorooctane sulfonate [PFOS], perfluorononanoate [PFNA], and perfluorohexane sulfonate [PFHxS]) in sera collected during pregnancy, at birth, and at ages 3, 8, and 12 years from 221 mother-child pairs in the HOME Study (enrolled 2003-06, Cincinnati, Ohio). We measured cardiometabolic risk factors using physical examinations, fasting serum biomarkers, and dual-energy X-ray absorptiometry scans at age 12 years. Cardiometabolic risk summary scores were calculated by summing age- and sex-standardized z-scores for individual cardiometabolic risk factors. We used multiple informant models to estimate covariate-adjusted associations of serum PFAS concentrations (log2-transformed) at each visit with cardiometabolic risk scores and their individual components, and tested for differences in associations across visits.

RESULTS

The associations of serum PFOA concentrations with cardiometabolic risk scores differed across visits (P for heterogeneity = 0.03). Gestational and cord serum PFOA concentrations were positively associated with cardiometabolic risk scores (βs and 95% confidence intervals [95% CIs]: gestational 0.8 [0.0, 1.6]; cord 0.9 [-0.1, 1.9] per interquartile range increase). These positive associations were primarily driven by homeostatic model assessment for insulin resistance index (β = 0.3 [0.1, 0.5]) and adiponectin to leptin ratio (β = -0.5 [-1.0, 0.0]). Other individual cardiometabolic risk factors associated with gestational PFOA included insulin and waist circumference. Gestational and cord PFHxS were also associated with higher cardiometabolic risk scores (βs: gestational 0.9 [0.2, 1.6]; cord 0.9 [0.1, 1.7]).

CONCLUSION

In this cohort of children with higher gestational PFOA exposure, fetal exposure to PFOA and PFHxS was associated with unfavorable cardiometabolic risk in adolescence.

Dietary Carbohydrates and Insulin Resistance in Adolescents from Marginalized Areas of Chiapas, México

Evidence of the role that dietary carbohydrates (total carbohydrates, dietary fiber, total sugars, dietary glycemic index (GI) and glycemic load (GL)) exerts on insulin levels in adolescents is controversial. Thus, the aim of this study was to assess the association between dietary carbohydrates and insulin resistance in adolescents from Chiapas, México. A cross-sectional study was conducted in 217 adolescents. Sociodemographic, anthropometric, dietary and biochemical data were obtained. Total carbohydrates, dietary fiber, total sugars, dietary GI and GL were calculated from 24 h recalls. Two validated cut-off points for the homeostasis model assessment of insulin resistance (HOMA-IR) were used as surrogates of insulin resistance. Fasting insulin levels ≥ 14.38 μU/mL were considered as abnormal. Multivariate logistic regression models were fitted to assess the association between tertiles of dietary carbohydrates and insulin resistance or hyperinsulinemia. In our study, adolescents with the highest dietary fiber intake had lower odds of HOMA-IR > 2.97 (OR = 0.34; 95% CI: 0.13-0.93) when adjusted for sex, age, body fat percentage and saturated fatty acids intake. No significant associations were found for the rest of the carbohydrate variables. In summary, high-fiber diets reduce the probability of insulin resistance in adolescents from marginalized areas of Chiapas, México.

Homeostasis Model Assessment cut-off points related to metabolic syndrome in children and adolescents: a systematic review and meta-analysis

The aim of this study was to perform a systematic review and meta-analysis of cut-off points of Homeostasis Model Assessment (HOMA-IR) to determine metabolic syndrome (MetS) in children and adolescents. A literature search was conducted in MEDLINE (via PubMed), EMBASE, Web of Science, Proquest, and Scopus databases from their inception to June 2018. Random effects models for the diagnostic odds ratio (dOR) value computed by Moses' constant for a linear model and 95% confidence intervals (CIs) were used to calculate the accuracy of the test. Hierarchical summary receiver operating characteristic curves (HSROC) were used to summarize the overall test performance. Six published studies were included in the meta-analysis that included 8732 children and adolescents. The region of HOMA-IR (i.e., dOR) associated with MetS range from 2.30 to 3.54. The pooled accuracy parameters from the studies that evaluated the diagnostic odds ratio of HOMA-IR ranged from 4.39 to 37.67.Conclusion: the HOMA-IR test may be useful for early evaluating children and adolescents with insulin resistance (IR). Furthermore, they present a good diagnostic accuracy independently of the definition of MetS used. According to the studies, the HOMA-IR cut point to avoid MetS risk ranged from 2.30 to 3.59.What is Known:• There is no consensus to define the optimal cut-off point of Homeostasis Model Assessment-Insulin Resistance in children and adolescents associated with Metabolic Syndrome.What is New:• The Homeostasis Model Assessment-Insulin Resistance test may be useful for early evaluations in children and adolescents with insulin resistance and presents a good diagnostic accuracy independently of the definition of Metabolic Syndrome used.• The Homeostasis Model Assessment-Insulin Resistance cut point to avoid Metabolic Syndrome risk ranged from 2.30 to 3.59.