Distribución de la circunferencia de la cintura y de la relación circunferencia de la cintura con respecto a la talla según la categoría del índice de masa corporal en los pacientes atendidos en consultas de endocrinología y nutrición

IntroductionWaist circumference (WC) and the waist-to-height ratio (WHtR) are anthropometric measures widely used in clinical practice to evaluate visceral fat and the consequent cardiovascular risk. However, risk thresholds should be standardized according to body mass index (BMI).ObjectiveTo determine the distribution of WC and WHtR according to the BMI cut-points currently used to describe overweight and obesity.Materials and methodsWC, WHtR and BMI were measured in 3521 adult patients (>18 years) attended in Endocrinology and Nutrition units.ResultsA total of 20.8% (734 patients) were diabetic. Obesity was found in 82.1% of diabetic patients and in 75% of non-diabetic patients. The WC thresholds proposed by the National Institute of Health (102 cm in men, 88 cm in women), Bray (100 cm in men, 90 cm in women) and the International Diabetes Federation (94 cm in men, 80 cm in women) were exceeded by 92.9%, 94.8% and 98.4% of obese men, 96.8%, 95.5% and 99.7% of obese women, 79.1%, 83.1% and 90% of diabetic men and 95.5%, 81.5% and 97.4% of diabetic women, respectively. Thresholds adapted to the degree of obesity (90, 100, 110 and 125 cm in men and 80, 90, 105 and 115 cm in women for normal BMI, overweight, obesity I and obesity greater than I) were exceeded by 58.4% of obese men, 54.2% of obese women, 57.5% of diabetic men and 60.7% of diabetic women. WC was higher in men, and BMI and the WHtR were higher in women. The WC of diabetic women equalled that of men, and WC, WHtR and BMI were higher in diabetic than in non-diabetic women (p<0.001). WC (p<0.005), WHtR (p<0.001) and BMI (p<0.5) were also higher in diabetic than in non-diabetic men.ConclusionWC and WHtR thresholds by BMI discriminated diabetic and obese patients better than single thresholds, and can be represented graphically by the distribution of percentile ranks of WC and WHtR by BMI.ik     

Waist circumference percentiles in children and adolescents between 6 and 14 years from Santiago,Chile

ObjectiveTo describe the percentile distribution of waist circumference (WC) by sex and age in a representative sample of children and adolescents of lower-middle and low socioeconomic status in Santiago, Chile.MethodsA cross-section of 3022 primary-school students between the ages of 6 and 14 from middle-low and low-class schools of Santiago. Ten schools from the Primary Education Society (SIP) in Santiago, Chile, were selected at random. WC was measured under standardized procedures as instructed by the WHO (midpoint between lower costal margin and iliac crest). The population was categorized between percentiles 10 and 90 and divided by sex and age.ResultsWC tends to increase with age in both males and females, but no significant differences were found in the percentiles by age for boys and girls at any age range (p > 0.05). In our sample, comparing Chilean children with other populations (British, Australian, European-American, African-American, Mexican – American and Colombian), Chilean children have shown a significantly greater WC (p < 0.05).ConclusionsWe present new WC reference values for Chilean children according to sex and age from a representative sample of Chilean population. These can be considered as a new anthropometric assessment tool for estimating cardiometabolic risk in Chilean children.     

Lipid Accumulation Product,Visceral Adiposity Index,And Chinese Visceral Adiposity Index As Markers Of Cardiometabolic Risk In Adult Growth Hormone Deficiency Patients: A Cross-Sectional Study

Objective: Adult growth hormone deficiency (AGHD) is associated with cardiometabolic risk factors. Given that cardiovascular disease (CVD) is an important cause of morbidity and mortality in the AGHD population, there is a need for alternative, noninvasive methods of assessing cardiometabolic risk in this population. The Chinese visceral adiposity index (CVAI) is a new marker of visceral fat dysfunction based on age, body mass index (BMI), waist circumference (WC), and metabolic parameters. CVAI is well correlated with insulin resistance (IR) and is better at predicting metabolic syndrome (MS) than BMI and WC. This study aims to examine the reliability of the lipid accumulation product (LAP), visceral adiposity index (VAI), and CVAI as cardiometabolic risk markers in AGHD patients.Methods: A total of 91 patients diagnosed with AGHD were divided into 4 groups according to CVAI quartile. We investigated the relationship between the patients' clinical and biochemical features, cardiometabolic risk assessed by cardiometabolic risk indices, the Framingham and atherosclerotic cardiovascular disease (ASCVD) risk scores, LAP, VAI, and CVAI.Results: The CVAI scores of patients were significantly higher than those of control patients. Increased CVAI significantly correlated with higher BMI, WC, waist-hip ratio (WHR), and triglycerides (TG), Framingham risk score and atherosclerotic cardiovascular disease lifetime risk score (P≤.001), with lower growth hormone (GH) and high-density lipoprotein cholesterol (HDL-C) levels (P≤.001).Conclusion: Our results suggest that CVAI may be a good marker of cardiometabolic risk in AGHD patients and could be used to diagnose CVD development and vascular accidents.Abbreviations: AGHD = adult growth hormone deficiency; ASCVD = atherosclerotic cardiovascular disease; AUROC = area under the receiver operating characteristic curve; BMI = body mass index; CVAI = Chinese visceral adiposity index; CVD = cardiovascular disease; DBP = diastolic blood pressure; GH = growth hormone; GHRT = GH replacement therapy; HDL-C = high-density lipoprotein cholesterol; IGF-1 = insulin like factor-1; IGFBP-3 = insulin like factor binding protein-3; IR = insulin resistance; LAP = lipid accumulation product; MS = metabolic syndrome; SBP = systolic blood pressure; TC = total cholesterol; TG = triglycerides; VAI = visceral adiposity index; WC = waist circumference; WHR = waist-to-hip ratio     

A Comparison between BMI,Waist Circumference,and Waist-To-Height Ratio for Identifying Cardio-Metabolic Risk in Children and Adolescents

Background

There is controversial evidence on the associations between anthropometric measures with clustering of cardiovascular disease risk factors in pediatric ages. We aimed to examine the associations between body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) with clustered cardiometabolic risk factors and to determine whether these anthropometric variables can be used to discriminate individuals with increased cardiometabolic risk (increased clustered triglycerides, HDL-cholesterol, systolic and diastolic blood pressure, and HOMA-IR).

Methods

The study sample of 4255 (2191 girls and 2064 boys) participants (8–17 years) was derived from pooled cross-sectional data comprising five studies. Outcomes included a continuous cardiometabolic risk factor z-score [corresponding to the sum of z-scores for triglycerides, HDL-cholesterol, systolic and diastolic blood pressure (mean arterial pressure), and HOMA-IR] and children with ≥1.0 SD in this score were defined as being at risk for clustering cardiometabolic risk factors.. Exposure variables were BMI, WC, WHtR. Statistics included mixed-effect regression and ROC analysis.

Results

All anthropometric variables were associated with clustered risk and the magnitudes of associations were similar for BMI, WC, and WHtR. Models including anthropometric variables were similar in discriminating children and adolescents at increased risk with areas under the ROC curve between 0.70 and 0.74. The sensitivity (boys: 80.5–86.4%; girls: 76.6–82.3%) was markedly higher than specificity (boys: 51.85–59.4%; girls: 60.8%).

Conclusions

The magnitude of associations for BMI, WC, and WHtR are similar in relation to clustered cardiometabolic risk factors, and perform better at higher levels of BMI. However, the precision of these anthropometric variables to classify increased risk is low.     

Effects of a Multi-Disciplinary Lifestyle Intervention on Cardiometabolic Risk Factors in Young Women with Abdominal Obesity: A Randomised Controlled Trial

Background

Young women are under-represented in cardiovascular disease research, with obesity and cardiometabolic risk factor interventions generally targeting older adults. Furthermore, appropriate study designs for young women remain uncertain. This study aimed to assess the impact of a 12 week multi-disciplinary lifestyle intervention on cardiometabolic risk factors in premenopausal women with abdominal obesity.

Methods

Women aged 18–30 y with abdominal obesity [waist circumference (WC) ≥ 80 cm] were randomised to a 12 week lifestyle intervention (n = 26) of physical activity, nutrition education and cognitive behavioural therapy, or a wait-list control group (n = 17). Both groups completed anthropometric, biochemical, nutrition and fitness testing, at pre (0 weeks) and post (12 weeks), with intervention participants completed follow-up testing at 24 weeks.

Results

Results from a linear mixed model showed no between-group differences, other than increased physical activity in the intervention group, at post. In the intervention group alone, positive within-group changes were observed in WC, waist-hip-ratio (WHR), waist-height-ratio (WHtR), resting heart rate, blood pressure, predicted VO_2max, and total energy intake. Most changes were maintained at 24 weeks post-intervention. Similar within-group improvements were observed in control participants in WC, WHR, WHtR, and systolic blood pressure but no changes were detected in physical activity and nutrition.

Conclusions

Cardiometabolic risk factors were decreased as a result of a lifestyle intervention in young women with abdominal obesity. It is difficult to describe observations in the control group without greater understanding of the behaviour of wait-list participants.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12612001017819     

Age-Dependent Influence of Gender on the Association Between Obesity and a Cluster of Cardiometabolic Risk Factors

BackgroundObesity is a main risk factor in metabolic syndrome. Gender is known to influence the risk of obesity and other cardiovascular risk factors. However, it remains to be determined whether there is a gender-specific difference in the relationship between obesity and accumulation of other cardiometabolic risk factors such as hypertension, dyslipidemia, and diabetes.ObjectiveThe aim of this study was to determine whether the association between obesity and a cluster of other cardiometabolic risk factors is modified by gender.MethodsThe subjects were 17,791 Japanese men and women who were divided into younger (35–40 years) and older (60–70 years) age groups. The relationships between obesity (body mass index [BMI] ≥25 kg/m² or waist-to-height ratio [WHtR] ≥0.5) and multiple cardiometabolic risk factors (≥2 of the risk factors of high blood pressure, dyslipidema, and hyperglycemia) were compared between men and women in each age group.ResultsIn the younger group, the crude odds ratios (ORs) for multiple cardiometabolic risk factors in obese versus nonobese subjects were significantly higher in women than in men (BMI: 6.23 [range, 5.53–7.02] in men vs 16.63 [range, 12.37–22.37] in women, P < 0.01; WHtR: 6.04 [range, 5.36–6.81] in men vs 9.77 [range, 7.14–13.37] in women, P < 0.01), whereas this difference was not found in the older group (BMI: 3.03 [range, 2.69–3.42] in men vs 2.92 [range, 2.33–3.67] in women P = 0.076; WHtR: 3.11 [range, 2.78–3.47] in men vs 2.50 [range, 2.02–3.09] in women, P < 0.05). On multivariate logistic regression analysis, the ORs for multiple cardiometabolic risk factors after adjusting for age, smoking, alcohol consumption, and regular exercise in subjects with versus subjects without a large waist circumference tended to be higher in women than in men in the younger group but not in the older group. The ORs of the interaction term consisting of gender and each adiposity index for multiple cardiometabolic risk factors were significantly higher than a reference level of 1.00 in the younger group (BMI: 2.68 [range, 1.95–3.69], P < 0.01; WHtR: 1.62 [range, 1.16–2.27], P < 0.01) but not in the older group (BMI: 0.95 [range, 0.74–1.23], P = 0.712; WHtR: 0.80 [range, 0.63–1.02], P = 0.066).ConclusionThe results suggest that the association between obesity and a cluster of cardiometabolic risk factors is stronger in women than in men, and this gender-specific difference exists in younger (35–40 years) but not in older (60–70 years) individuals.     

Association of Adiposity Indices with Platelet Distribution Width and Mean Platelet Volume in Chinese Adults

Hypoxia is a prominent characteristic of inflammatory tissue lesions. It can affect platelet function. While mean platelet volume (MPV) and platelet distribution width (PDW) are sample platelet indices, they may reflect subcinical platelet activation. To investigated associations between adiposity indices and platelet indices, 17327 eligible individuals (7677 males and 9650 females) from the Dongfeng-Tongji Cohort Study (DFTJ-Cohort Study, n=27009) were included in this study, except for 9682 individuals with missing data on demographical, lifestyle, physical indicators and diseases relative to PDW and MPV. Associations between adiposity indices including waist circumstance (WC), waist-to-height ratio (WHtR), body mass index (BMI), and MPV or PDW in the participants were analyzed using multiple logistic regressions. There were significantly negative associations between abnormal PDW and WC or WHtR for both sexes (p _trend<0.001 for all), as well as abnormal MPV and WC or WHtR among female participants (p _trend<0.05 for all). In the highest BMI groups, only females with low MPV or PDW were at greater risk for having low MPV (OR=1.33, 95% CI=1.10, 1.62 p _trend<0.001) or PDW (OR=1.34, 95% CI=1.14, 1.58, p _trend<0.001) than those who had low MPV or PDW in the corresponding lowest BMI group. The change of PDW seems more sensitive than MPV to oxidative stress and hypoxia. Associations between reduced PDW and MPV values and WC, WHtR and BMI values in Chinese female adults may help us to further investigate early changes in human body.     

Nonfunctioning Adrenal Incidentalomas are not Clinically Silent: A Longitudinal Cohort Study

Objective: The association between nonfunctioning adrenal incidentalomas (NFAIs) and cardiometabolic diseases remains controversial. This retrospective cohort study investigated whether NFAIs are related with prevalent and incident cardiometabolic diseases.Methods: This study included 154 patients with biochemically confirmed NFAIs and 1:3 age and sex-matched controls without adrenal incidentalomas (n = 462) among subjects who underwent abdominal computed tomography at a single healthcare center in 2003–2012. Electronic medical records were reviewed for comorbidities at baseline and during a mean follow-up of 7.5 years. The logistic regression analysis for prevalent cardiometabolic diseases and the survival analysis for incident cardiometabolic diseases were performed.Results: The subjects were 55.7 ± 8.8 years of age and predominantly male (73.1%). The NFAI group had a higher body mass index compared to the age and sex-matched control group (25.1 ± 2.8 vs. 24.0 ± 2.8 kg/m²; P<.001). In a cross-sectional design, covariate-adjusted logistic regression showed significantly higher odds ratios (ORs) for diabetes mellitus and hypertension in the NFAI group (adjusted OR [95% confidence interval [CI]], 1.89 [1.17 to 3.06] and 2.26 [1.47 to 3.50], respectively). The NFAI group had a 2-fold higher risk of insulin resistance (adjusted ORs [95% CI], 2.03 [1.06 to 3.90]). Moreover, NFAI subjects with diabetes mellitus had a greater increase in size of adrenal lesions than those without diabetes mellitus (3.4 ± 5.5 vs. 1.4 ± 5.5 mm; P =.048). However, in the survival analysis, the incidence of any cardiometabolic diseases did not differ between the NFAI and control groups.Conclusion: NFAIs are related to prevalent diabetes mellitus or hypertension in our cross-sectional study. However, the presence of NFAIs did not affect the development of cardiometabolic diseases.Abbreviations: ACTH = adrenocorticotropic hormone; AI = adrenal incidentaloma; BMI = body mass index; CI = confidence interval; CT = computed tomography; HbA1c = hemoglobin A1c; HOMA-IR = homeostasis model assessment of insulin resistance; HU = Hounsfield units; MACE = mild autonomous cortisol excess; NFAI = nonfunctioning adrenal incidentaloma; OR = odds ratio     

Evaluation of Para- and Perirenal Fat Thickness and its Association with Metabolic Disorders in Polycystic Ovary Syndrome

Objective: The aim of this study was to compare para- and perirenal fat (PFT) and subcutaneous abdominal fat (SFT) measurements between patients with polycystic ovary syndrome (PCOS) and control subjects and to assess the possible relation with metabolic disorders.Methods: This study included 68 patients with PCOS and 40 age- and body mass index (BMI)-matched healthy controls. We evaluated anthropometric, hormonal, and metabolic parameters, and abdominal ultrasonography was performed to measure PFT and SFT.Results: The mean PFT values were 6.1 ± 2.9 mm in patients with PCOS and 4.3 ± 2.3 mm in healthy controls (P = .002). SFT values were also higher in the patient group (9.6 ± 5 mm) compared to healthy subjects (3.5 ± 0.5 mm) (P = .017). A significant positive correlation was found between PFT and BMI (r = 0.368), waist circumference (WC) (r = 0.441), Ferriman-Gallwey (FG) score (r = 0.313), blood pressure (systolic, SBP, r = 0.213; diastolic, DBP, r = 0.215), plasma glucose (r = 0.195), homeostasis model assessment-insulin resistance (HOMA-IR, r = 0.273), SFT (r = 0.555). Conversely, negative correlations were found between PFT and estradiol (r = -0.218) and sex hormone-binding globulin (SHBG, r = -0.304). Nonobese PCOS patients (6.1 ± 3.07 mm) had higher PFT values than nonobese controls (3.47 ± 1.5 mm); however, SFT measurements did not differ (P = .086). In multiple linear regression analysis, SFT (P = .006) was a significant and independent predictor for PFT, along with WC (P = .023). In a stepwise model, SFT was the predictor of PFT (P = .001).Conclusion: PFT values were higher particularly in nonobese PCOS patients compared to nonobese control subjects. There was a significant interaction between PCOS and obesity on PFT.Abbreviations: BMI = body mass index; CT = computed tomography; DBP = diastolic blood pressure; FPG = fasting plasma glucose;; HDL-cholesterol = high-density lipoprotein cholesterol; HOMA-IR = homeostasis model assessment-insulin resistance; hsCRP = high-sensitivity C-reactive protein; LDL-cholesterol = low-density lipoprotein cholesterol; LH = luteinizing hormone; NCAH = nonclassic congenital adrenal hyperplasia; 17-OHP = 17-hydroxyprogesterone; PCOS = polycystic ovary syndrome; PFT = para- and perirenal fat; SAT = subcutaneous abdominal adipose tissue; SBP = systolic blood pressure; SFT = abdominal subcutaneous fat thickness; TG = triglyceride; US = ultrasound; VAT = visceral abdominal adipose tissue; WC = waist circumference     

Association of Simple Anthropometric Indices and Body Fat with Early Atherosclerosis and Lipid Profiles in Chinese Adults

Objective

The discriminatory capability of different adiposity indices for atherosclerosis and lipid abnormalities remains uncertain. This study aimed to identify the best adiposity index for predicting early atherosclerosis and abnormal lipid profiles among anthropometric parameters and body fat measures in middle-aged and elderly Chinese.

Method

A total of 2,063 women and 814 men (57.6±5.2 y) were recruited for this community-based cross-sectional study. Body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) were assessed. Body fat mass and its percentage values for the whole body and trunk were measured by bioelectrical impedance analysis (BIA). The intima-media thicknesses (IMTs) of the common carotid arteries (CCA), internal carotid arteries (ICA) and bifurcation (BIF) were determined via B-mode ultrasound. The fasting lipid profiles were assessed.

Results

With per SD increase of adiposity indices, the magnitude of the changes of IMT values and lipid profiles was more substantial for WC, WHR and WHtR in both genders. A multivariate logistic regression analysis indicated that WC, WHR and WHtR were more sensitive in predicting the presence of intima-media thickening at the three segments as well as the lipids disturbances in women and men. In general, BIA-derived measures have no added predictive value for IMT-thickening as opposed to those three traditional abdominal measures.

Conclusion

Our findings suggest that abdominal anthropometric measures including WC, WHR and WHtR are sensitive for discriminating carotid atherosclerosis and lipids abnormalities. WC is the best index because of its simplicity in routine use.     

Breast Volume is an Independent Predictor of Visceral and Ectopic Fat in Premenopausal Women

It is suggested that a large breast size among women may predict type 2 diabetes risk independent of BMI and waist circumference (WC). The purpose of this study was to determine the independent associations of breast volume with cardiometabolic risk factors and regional fat distribution. A total of 92 overweight or obese premenopausal women (age = 39.9 ± 6.8 years) underwent full‐body magnetic resonance imaging (MRI) for the assessment of breast volume, visceral adipose tissue (VAT), abdominal and lower‐body subcutaneous AT (SAT), and intermuscular AT (IMAT), a 2‐h oral glucose tolerance test (OGTT), and fasting phlebotomy for assessment of triglyceride, total, high‐density lipoprotein–, and low‐density lipoprotein–cholesterol levels. Breast volume was not associated with any of the cardiometabolic risk factors assessed (P > 0.05). However, VAT was consistently associated with a number of cardiometabolic risk factors (OGTT glucose, OGTT insulin, and triglyceride levels) after controlling for age, BMI, WC, breast volume, and the other AT depots. In univariate models, breast volume was positively associated with VAT, IMAT, and abdominal and lower‐body SAT (P < 0.05). After controlling for age, BMI, and WC level, breast volume remained positively associated with VAT and IMAT (P < 0.05), such that women with the highest breast volume had ～1.1 and 1.3 kg more VAT and IMAT, respectively, but no more abdominal or lower‐body SAT, by comparison to women with the smallest breast volume. Thus, the previously documented association between breast size and type 2 diabetes risk may be in part explained by excess VAT and/or IMAT deposition.     

Comparison of measures of adiposity in identifying cardiovascular disease risk among Ethiopian adults

We sought to determine which measures of adiposity can predict cardiovascular disease (CVD) risk and to evaluate the extent to which overall and abdominal adiposity are associated with cardiometabolic risk factors among working adults in Ethiopia. This was a cross-sectional study of 1,853 individuals (1,125 men, 728 women) in Addis Ababa, Ethiopia. The World Health Organization STEPwise approach was used to collect sociodemographic data, anthropometric measurements, and blood samples among study subjects. Fasting blood glucose (FBG) and lipid concentrations were measured using standard approaches. Spearman's rank correlation, receiver operating characteristic (ROC) curves, and logistic regression were employed to determine the association and predictive ability (with respect to CVD risk factors) of four measures of adiposity: BMI, waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). Overall, FBG is best associated with WHtR in men and WC in women. Systolic blood pressure (SBP) is most strongly associated with BMI in men, but with WC in women. Compared to those with low BMI and low WC, the risk of having CVD is the highest for those with high BMI and high WC and those with high WC and low BMI. Review of ROC curves indicated that WC is the best predictor of CVD risk among study subjects. Findings from our study underscore the feasibility and face validity of using simple measures of central and overall adiposity in identifying CVD risk in resource-poor settings.     

Pediatric Visceral Adiposity Index Adaptation Correlates with Homa-Ir,Matsuda, and Transaminases

Objective: Visceral adiposity index (VAI) is a mathematical model associated with cardiometabolic risk in adults, but studies on children failed to support this association. Our group has proposed a pediatric VAI model using pediatric ranges, but it has not yet been evaluated and needs further adjustments. The objective of this study was to further adjust the proposed pediatric VAI by age, creating a new pediatric metabolic index (PMI), and assess the correlation of the PMI with insulin resistance indexes and hepatic enzymes.Methods: A cross-sectional design with data from 396 children (age 5 to 17 years) was analyzed with a generalized linear model to find the coefficients for triglycerides, high-density-lipoprotein cholesterol, and waist circumference–body mass index quotient. The model was constructed according to sex and age and designated PMI. A cross-validation analysis was performed and a receiver operating characteristic curve was used to determine cut-off points.Results: Significant moderate correlation was found between PMI and homeostatic model assessment of insulin resistance (HOMA-IR) (r = 0.452; P = .003), Matsuda (r = -0.366; P = .019), alanine aminotransferase (r = 0.315, P = .045), and γ-glutamyltransferase (r = 0.397; P = .010). A PMI score >1.7 was considered as risk.Conclusion: PMI correlates with HOMA-IR, Matsuda, and hepatic enzymes. It could be helpful for identifying children at risk for cardiometabolic diseases.Abbreviations:ALT = alanine transaminaseBMI = body mass indexGGT = γ-glutamyltransferaseHDL-C = high-density-lipoprotein cholesterolHOMA-IR = homeostatic model assessment of insulin resistancehs-CRP = high sensitivity C-reactive proteinISI = insulin sensitivity indexNAFLD = nonalcoholic fatty liver diseasePMI = pediatric metabolic indexQUICKI = quantitative insulin sensitivity check indexROC = receiver operating characteristicTG = triglycerideTNF-α = tumor necrosis factor–alphaVAI = visceral adiposity indexVAT = visceral adipose tissueWC = waist circumference     

Prevalence of Abdominal Obesity in Spanish Children and Adolescents. Do We Need Waist Circumference Measurements in Pediatric Practice?

Background

Evidence indicates that central adiposity has increased to a higher degree than general adiposity in children and adolescents in recent decades. However, waist circumference is not a routine measurement in clinical practice.

Objective

This study aimed to determine the prevalence of abdominal obesity based on waist circumferences (WC) and waist to height ratio (WHtR) in Spanish children and adolescents aged 6 to 17 years. Further, the prevalence of abdominal obesity (AO) among normal and overweight individuals was analyzed.

Design

Data were obtained from a study conducted from 1998 to 2000 in a representative national sample of 1521 children and adolescents aged 6 to 17 years (50.0% female) in Spain. WC and WHtR measurements were obtained in addition to BMI. AO was defined as WHtR ≥0.50 (WHtR-AO), sex and age specific WC≥90^th percentile (WC-AO1), and sex and age specific WC cut-off values associated with high trunk fat measured by by dual-energy X-ray absorptiometry (WC-AO2).

Results

IOTF- based overweight and obsity prevalence was 21.5% and 6.6% in children and 17.4% and 5.2% in adolescents, respectively. Abdominal obesity (AO) was defined as WHtR≥0.50 (WHtR-AO), sex- and age-specific WC≥90th percentile (WC-AO1), and sex- and age-specific WC cut-off values associated with high trunk fat measured by dual-energy X-ray absorptiometry (WC-AO2). The respective prevalence of WHtR-AO, WC-AO1, and WC-AO2 was 21.3% (24.6% boys; 17.9% girls), 9.4% (9.1% boys; 9.7% girls), and 26.8% (30.6% boys;22.9% girls) in children and 14.3% (20.0% boys; 8.7% girls), 9.6% (9.8% boys; 9.5% girls), and 21.1% (28.8% boys; 13.7% girls) in adolescents.

Conclusion

The prevalence of AO in Spanish children and adolescents is of concern. The high proportion of AO observed in young patients who are normal weight or overweight indicates a need to include waist circumference measurements in routine clinical practice.     

Reaction time: Does it relate to weight status in children?

It has been recently reported that reaction time (RT) is related to weight status [measured by body mass index (BMI)] in young, adult and older people. However, there is little evidence for children, and the similar studies included small sample of participants. The aim of this study was to evaluate the relationship between a new RT test and weight status among a sample of 7–11 year old schoolboys. Therefore, 533 apparently healthy schoolboys underwent clinical reaction time (RT_clin) measurements and standard anthropometry. Participants according to different obesity indices [waist circumference (WC), waist to height ratio (WHtR), BMI and fat%] were assigned to different weight status categories. Results indicated that time of RT_clin decreased as age of the boys increased (F = 63; P < 0.01). No significant difference was observed for RT_clin among the BMI, WC, WHtR and fat% categories after controlling for age (P > 0.05). In conclusion, it seems that there is no relationship between simple RT (measured by RT_clin) and weight status in the boys. Additional studies for finding relationship between RT and weight status are needed by including larger samples of participants, various age groups and various RT tests.     

The relationship between ultrasonographically measured testicular volumes and cord blood inhibin B concentrations in healthy term male neonates

Serum inhibin B (INHB) concentrations are associated with testicular volumes (TV) in all periods of childhood. The aim of the study was to investigate the relationship between TV measured by ultrasonography (US) and cord blood inhibin B and total testosterone (TT) concentrations, stratified by mode of delivery. In total 90 male infants were included. Testes of healthy, term newborns were evaluated by US on the third day after delivery. TV were calculated using two formulae: The ellipsoid formula [length (mm) × width (mm²) × π/6] and Lambert formula [length (mm) x width (mm) x height (mm) x 0.71]. Cord blood was taken for the determination of total testosterone (TT) and INHB. TT and INHB concentrations were evaluated according to TV percentiles (<10th, 10th-90th, >90th). There was a strong positive correlation between mean TV calculated with both formulae by percentile group (r = 0.777, r = 0.804, r = 0.846; p < 0.001). Cord blood INHB, but not TT were significantly lower in newborns with TV < 10th percentile compared to those with TV between 10 and 90th percentile and > 90th percentile (p < 0.05). There was a positive correlation between left and right TV calculated by either formula, and cord blood INHB (r = 0.212, 0.313, 0.320, 0.246, p < 0.05), not TT. There was no significant difference between hormones and TV when grouped by mode of delivery (p > 0.05). The Lambert and ellipsoid formulas are equally reliable in calculating neonatal testicular by ultrasound. INHB concentration is high in cord blood and positively correlated with neonatal TV. Cord blood INHB concentration may be an indicator for early detection of testicular structure and function disorders in neonates.     

Skeletal Maturation in the Current Pediatric Mexican Population

Objective: The most commonly used methods for bone age (BA) reading were described in the Caucasian population decades ago. However, there are secular trends in skeletal maturation and different BA patterns between ethnic groups. Automated BA reading makes updating references easier and more precise than human reading. The objective of the present study was to present automated BA reference curves according to chronological age and gender in the Mexican population and compare the maturation tempo with that of other populations.Methods: The study included 923 healthy participants aged 5 to 18 years between 2017 and 2018. A hand radio-graph was analyzed using BoneXpert software to obtain the automated BA reading according to Greulich and Pyle (G&P) and Tanner-Whitehouse 2 (TW2) references. We constructed reference curves using the average difference between the BA and chronological age according to sex and age.Results: The G&P and TW2 automated reference curves showed that Mexican boys exhibit delays in BA during middle childhood by 0.5 to 0.7 (95% confidence interval &lsqb;CI], -0.9 to -0.2) years; however, they demonstrate an advanced BA of up to 1.1 (95% CI, 0.8 to 1.4) years at the end of puberty. Mexican girls exhibited a delay in BA by 0.3 to 0.6 (95% CI, -0.9 to -0.1) years before puberty and an advanced BA of up to 0.9 (95% CI, 0.7 to 1.2) years at the end of puberty.Conclusion: Mexican children aged <10 years exhibited a delay in skeletal maturity, followed by an advanced BA by approximately 1 year at the end of puberty. This may affect the estimation of growth potential in this population.     

Utility of Hemoglobin-A1C in Nondiabetic Women With Polycystic Ovary Syndrome

ObjectiveHemoglobin A1c (A1C) >5.7% is now accepted as a biomarker for identifying individuals at risk for diabetes. Compared to the general population, women with polycystic ovary syndrome (PCOS) have a higher risk for diabetes. Our goal was to determine what glucose homeostasis abnormalities can be identified by A1C >5.7% in women with PCOS.MethodsIn a cross-sectional study, nondiabetic women with PCOS (according to the National Institutes of Health [NIH] criteria) were divided into 2 groups based on A1C (<5.7% [n = 23] and >5.7% [n = 25]). Oral glucose tolerance tests (OGTT) and frequently sampled intravenous glucose tolerance tests (FS-IVGTT) were conducted, and body composition, cardiovascular risk factors, and sex steroid levels were assessed.ResultsCompared to women with A1C <5.7%, those with A1C >5.7% were older (35.1 ± 1.1 years vs. 31.1 ± 1.1 years; P = .04), had higher glucose levels at fasting and during OGTT, and had a lower insulin sensitivity index (SI: 2.0 ± 0.2 vs. 4.2 ± 0.6; P = .0195) and disposition index (DI: 1,014 ± 82 vs. 1,901 ± 217; P = .011) during FS-IVGTT. They also had higher triglycerides, high-sensitivity C-reactive protein (hs-CRP), and fatty acid-binding protein 4 (FABP4) levels. There was no difference in serum androgen levels.ConclusionA1C >5.7% identified the subgroup of PCOS patients with higher insulin resistance, inadequate compensatory insulin response, impaired glucose disposition, and increased cardiovascular risk factors. Thus, A1C represents an inexpensive and informative biomarker to identify PCOS patients at risk for metabolic abnormalities. (Endocr Pract. 2013;19:284-289)     

Thyroid Nodule Growth as A Predictor of Malignancy

Objective: To assess which measure of thyroid nodule growth on serial neck ultrasound, if any, is associated with malignancy.Methods: Retrospective exploratory chart review of malignant thyroid nodules assessed at Kingston Health Sciences Centre (2006–2016) and benign thyroid nodules (2016), at least 1 cm in diameter and with 2 ultrasounds completed at least 30 days apart. Groups were compared using independent samples Student's t test, chi-square test, or Mann-Whitney U test as appropriate, as well as multivariable logistic and linear regression modelling to adjust for age and baseline volume.Results: One hundred and seventy-eight nodules were included in the study. When growth was defined as >20% increase in 2 dimensions (minimum 2 mm), malignant nodules (MNs) underwent significantly more growth than benign nodules (BNs) (16.8% BN versus 29.8% MN &lsqb;P = .026]; odds ratio = 2.49; 95% confidence interval = 1.12 to 5.56). There was no significant difference between the groups when growth was defined as >2 mm/year or ≥50% volume growth. Nodules shrank >2 mm/year in each group and the difference was not statistically significant (24.2% BN versus 20.7% MN &lsqb;P = .449]). The median doubling time for the nodules that grew was 1022.1 days in the BN group and 463.2 days in the MN group (P = .036). The median doubling time for all nodules was 456.5 days in the BN group and 244.2 days in the MN group (P = .015).Conclusion: Thyroid nodule growth defined as >20% increase in 2 dimensions (minimum 2 mm) is associated with risk of malignancy. Nodule shrinkage did not distinguish between BNs and MNs.Abbreviations: BN = benign nodule; CI = confidence interval; FNA = fine needle aspiration; KHSC = Kingston Health Science Centre; MN = malignant nodule; OR = odds ratio; ROC = receiver operating characteristic     

The Correlation Between Metabolic Disorders And Tpoab/Tgab: A Cross-Sectional Population-Based Study

Objective: Studies have shown that metabolic abnormalities influence the immune system. Because the prevalence of metabolic and autoimmune thyroid diseases has increased synchronously, the correlation between them was worth exploring. The study objective was to investigate the relationship between metabolic disorders and thyroid auto-antibodies in euthyroid subjects.Methods: Data were obtained from the Thyroid Diseases and Diabetes Mellitus project survey of 55,891 subjects from 31 provinces in China. The body mass index (BMI), waist circumference (WC), blood pressure, thyroid peroxidase antibodies (TPOAbs), thyroglobulin antibodies (TgAbs), thyroid-stimulating hormone (TSH), urinary iodine concentration, blood glucose, lipid profile, and uric acid levels were evaluated. Free thyroxine and free triiodothyronine levels were measured in patients with abnormal serum TSH levels.Results: In males, the BMI, WC, systolic blood pressure (SBP), diastolic blood pressure (DBP), and 2-hour post-glucose oral glucose tolerance test results of the TPOAb-/TgAb-positive group were significantly higher than those of the TPOAb-/TgAb-negative group. In females, the BMI, WC, SBP, DBP, total cholesterol, and low-density-lipoprotein cholesterol (LDL-C) in the TPOAb-/TgAb-positive group were significantly increased compared to the TPOAb-/TgAb-negative group. Multivariate analysis showed that in males, the odds ratio (OR) of positive TgAbs in the abdominal obesity group was 1.175 (95% confidence interval [CI], 1.016 to 1.359; P = .03), and the OR of positive TPOAbs in the hyperuricemia group was 1.195 (95% CI, 1.041 to 1.372; P = .011). In females, the OR of positive TgAbs was 1.19 (95% CI, 1.068 to 1.326; P = .002) in the high LDL-C group.Conclusion: Obesity, high LDL-C, and hyperuricemia were positively correlated with the prevalence of positive thyroid autoantibodies in euthyroid subjects in a gender-dependent manner. This cross-sectional survey showed that metabolic disorders are associated with increased positive thyroid autoantibody levels in euthyroid subjects in a gender-dependent manner.Abbreviations: AIT = autoimmune thyroiditis; BMI = body mass index; CI = confidence interval; DBP = diastolic blood pressure; FPG = fasting plasma glucose; FT3 = free triiodothyronine; FT4 = free thyroxine; HbA1c = glycated hemoglobin; HDL-C = high-density-lipoprotein cholesterol; LDL-C = low-density-lipoprotein cholesterol; OGTT2hPG = oral glucose tolerance test 2-hours post-glucose; OR = odds ratio; SBP = systolic blood pressure; TC = total cholesterol; TG = triglycerides; TgAb = thyroglobulin antibody; TPOAb = thyroid peroxidase antibody; TSH = thyroid-stimulating hormone; UA = uric acid; WC = waist circumference