Body composition of obese adolescents: association between adiposity indicators and cardiometabolic risk factors

Nutritional predictors associated with malnutrition in continuous ambulatory peritoneal dialysis patients

BACKGROUND

Currently in China, out of the total dialysis population, approximately 20% represents continuous ambulatory peritoneal dialysis (CAPD) and almost half of CAPD patients was affected by malnutrition. This study aimed to investigate the association between nutritional predictors and malnutrition with 5.1 years of dialysis according to the subjective global assessment (SGA) in continuous ambulatory peritoneal dialysis (CAPD) patients.

METHODS

A cross-sectional study was conducted from April 2013 to May 2018 and included 70 CAPD patients. The relationship between anthropometric and biochemical parameters with malnutrition was assessed by multiple logistic regression analysis.

RESULTS

The prevalence of malnutrition in CAPD patients was 52.9%. Our result revealed a 7.05-fold increased odds of malnutrition for patients with protein equivalent of total nitrogen appearance normalized to body weight (nPNA) < 1.0 g/kg per day (d) versus patients with normal nPNA (confidence interval (CI) 1.33-37.34; p < 0.05). Patients whose normalized protein catabolic rate (nPCR) was <1.2 g/(kg/d) had a significant positive association with malnutrition versus patients with normal nPCR (adjusted odds ratio (OR) 7.99; p < 0.05). Patients with dietary protein intake (DPI) < 1.0 g/(kg/d) had a higher likelihood of malnutrition than those with normal DPI (OR 12.73; p < 0.05). CAPD patients with upper arm circumference (UAC) < 23.2 cm had a high risk of malnutrition versus patients with normal UAC (OR 12.99; p < 0.05).

CONCLUSIONS

Our study suggested a close association between nPNA, DPI, nPCR, and UAC and malnutrition in CAPD patients. Further studies can be warranted the use of these variables as predictors and a malnutrition consequence among Chinese CAPD patients.

DEVELOPMENT AND VALIDATION OF EQUATIONS TO ESTIMATE VISCERAL ADIPOSE TISSUE IN MILITARY MEN

ABSTRACT Introduction It has been suggested that visceral adipose tissue (VAT) is associated with several non-communicable chronic diseases, but measuring it is difficult. Thus, anthropometry could be used because is easily applied in clinical practice. Objectives The present study aimed to develop and validate VAT estimation equations (Eq) in military men. Methods The sample consisted of 409 (mean age, 36.5 ± 6.7 years) military men in the Brazilian Army (BA) divided into an equation group (EG) ( n = 270; mean age, 37.0 ± 6.3 years) and a validation group (VG) ( n =139; mean age, 36.0 ± 7.2 years). Anthropometric, hemodynamic and DXA body composition evaluations ( GE iLunar ) were performed. The Student’s t test, Pearson’s correlation, and stepwise general linear regression were applied. Bland-Altman graphics were used to assess the concordance between VAT by Eq and by DXA. The level of significance was 95% ( p < 0.05). Results Age, waist circumference (WC), hip circumference and body mass index presented the main significant positive correlations with the VAT-DXA. Four Eq were created Eq1 ( r 2 = 0.793), Eq2 ( r 2 = 0.810), Eq3 ( r 2 = 0.817), and Eq 4 ( r 2 = 0.823) ( p < 0.05). No differences were observed between VAT by DXA and VAT by Eq ( p = 0.982, p = 0.970, p = 0.495 and p = 0.698). Bland-Altman analysis also presented good concordance as the bias was close to zero and was not statistically significant. Conclusion Eq2 (age*13.0 + WC*60.0 - 4975,.5) was more suitable because it is easier to apply, has a higher predictive power (81.0%), less bias (1.86) and validation yielded average VAT values close to those found in DXA. It may still be considered a valuable tool for other extensive epidemiological studies in military men in the BA and can be used in adult men. Evidence Level I: Development of diagnostic criteria on consecutive patients (with universally applied reference ‘‘gold’’ standard).

An Overview of the Role of Adipokines in Cardiometabolic Diseases

Obesity as an independent risk factor for cardiovascular diseases (CVDs) leads to an increase in morbidity, mortality, and a shortening of life span. The changes in heart structure and function as well as metabolic profile are caused by obese people, including those free of metabolic disorders. Obesity alters heart function structure and affects lipid and glucose metabolism, blood pressure, and increase inflammatory cytokines. Adipokines, specific cytokines of adipocytes, are involved in the progression of obesity and the associated co-morbidities. In the current study, we review the scientific evidence on the effects of obesity on CVDs, focusing on the changes in adipokines. Several adipokines have anti-inflammatory and cardioprotective effects comprising omentin, apelin, adiponectin, and secreted frizzled-related protein (Sfrp-5). Other adipokines have pro-inflammatory impacts on the cardiovascular system and obesity including leptin, tumor necrosis factor (TNF), retinol-binding protein4 (RBP-4), visfatin, resistin, and osteopontin. We found that obesity is associated with multiple CVDs, but can only occur in unhealthy metabolic patients. However, more studies should be designed to clarify the association between obesity, adipokine changes, and the occurrence of CVDs.

Adiposity and Fat-Free Mass of Children Born with Very Low Birth Weight Do Not Differ in Children Fed Supplemental Donor Milk Compared with Those Fed Preterm Formula

BACKGROUND

Many mothers of very-low-birth-weight (VLBW) infants (<1500 g) are unable to provide sufficient breast milk, and supplemental pasteurized donor human milk (donor milk) or preterm formula is required. The composition of donor milk differs from that of mother's milk and infants fed with donor milk often exhibit slower growth during hospitalization. The long-term impact of nutrient-enriched donor milk on growth, body composition, or blood pressure is unknown.

OBJECTIVE

We aimed to determine the effects of nutrient-enriched donor milk compared with preterm formula on growth, body composition, and blood pressure of children born preterm and with VLBW. Associations with in-hospital mother's milk intake were explored.

METHODS

This study was a follow-up of children at 5.5-y of age who participated in a randomized controlled trial evaluating the effect of nutrient-enriched donor milk (commencing at ≥120 mL·kg-1·d-1) or preterm formula fed as a supplement when mother's milk was unavailable. The trial intervention lasted 90 d or until hospital discharge, whichever occurred first. In this follow-up investigation, differences in total body fat percentage determined by using air displacement plethysmography (primary outcome), fat-free mass, skinfold thickness, waist circumference, BMI z scores, and blood pressure] were evaluated using linear regressions.

RESULTS

Of 316 surviving infants from the earlier trial, 158 (50%) participated in the current study (53% male). Mean ± SD birth weight and gestational age were 1013 ± 264 g and 27.9 ± 2.5 wk. The median (IQR) intervention period was 67.5 d (52.0-91.0 d). Mean ± SD age and BMI z score at follow-up were 5.7 ± 0.2 y and -0.3 ± 1.2. Supplemental nutrient-enriched donor milk, compared to preterm formula, was not associated with growth, body composition, or blood pressure. In-hospital mother's milk intake was positively associated with height z score at 5.5 y (β: 0.07; 95% CI: 0.004, 0.1; P = 0.04).

CONCLUSIONS

Supplemental nutrient-enriched donor milk and preterm formula during initial hospitalization results in comparable long-term growth and body composition in young children born VLBW. This trial was registered at clinicaltrials.gov as NCT02759809 and at isrctn.com as ISRCTN35317141.

Utilization of anthropometric parameters as a novel tool for detection of insulin resistance

BACKGROUND

Anthropometric parameters have been widely applied in evaluating muscle mass, insulin resistance (IR), and cardiometabolic diseases. Arm circumference (AC) and calf circumference (CC) are used as informative markers for sarcopenia. However, few studies concern the correlation between AC, CC and IR. The aim of the present survey is to investigate the relationship between AC, CC and homeostatic model assessment of insulin resistance (HOMA-IR).

METHODS

This cross-sectional observational study included 11,527 participants aged 40-85 years from the National Health and Nutrition Examination Survey (NHANES), 1999 to 2006. We divided the participants into male and female groups. Each group was then divided into four subgroups depending on their AC and CC levels.

RESULTS

After adjustment for multiple covariates, we observed a significant negative correlation between the CC and HOMA-IR. This study showed a significant positive correlation between the AC and HOMA-IR after multiple adjustments. Subjects in the highest CC quartiles tended to have the lowest HOMA-IR in both male and female group (P for trend <0.001 in all models).

CONCLUSIONS

CC may be a novel tool to guide public health policy and clinical predictor of IR in middle-aged and older people.

Association between mid-upper arm circumference and cardiometabolic risk in Chinese population: a cross-sectional study

OBJECTIVES

Upper body fat has been associated with an unfavourable cardiometabolic risk. We aimed to investigate the associations between mid-upper arm circumference (MUAC), a novel indicator of upper body fat, and a wide spectrum of cardiometabolic risk profiles in Chinese population.

DESIGN AND SETTING

Cross-sectional analyses were performed using data from a well-defined community in 2014, Shanghai, China.

PARTICIPANTS

A total of 6287 Chinese adults (2310 men and 3977 women) aged 40 years or older.

OUTCOME MEASURES

Multivariable logistic regression model was used to examine the associations of MUAC with cardiometabolic disorders including central obesity, diabetes, hypertension, hypertriglyceridaemia, low high-density lipoprotein (HDL) cholesterol and subclinical atherosclerosis.

RESULTS

In the overall participants, after multivariable adjustment, each 1 SD (3.13 cm) increment in MUAC was positively associated with central obesity (OR 2.05; 95% CI 1.85 to 2.28), hypertension (OR 1.10; 95% CI 1.03 to 1.19) and low HDL cholesterol (OR 1.10; 95% CI 1.01 to 1.22). Multivariable-adjusted ORs for subclinical atherosclerosis were gradually increased across increasing quartiles of MUAC with the lowest quartile as reference (quartile 2: OR 1.31; 95% CI 1.09 to 1.58; quartile 3: OR 1.33; 95% CI 1.10 to 1.62; quartile 4: OR 1.45; 95% CI 1.16 to 1.80; p for trend=0.005). Similar but more prominent associations were observed among women than men. In addition, MUAC was significantly interacted with diabetes (p for interaction=0.04) and insulin resistance (p for interaction=0.01) on subclinical atherosclerosis.

CONCLUSION

A greater MUAC was positively associated with higher risks of several cardiometabolic disorders and subclinical atherosclerosis in Chinese adults.

Relationship between DXA measured metrics of adiposity and glucose homeostasis; An analysis of the NHANES data

Introduction

Obesity is associated with insulin resistance and type 2 diabetes. Dual-energy X-ray absorptiometry (DXA) is a means of determining body composition and body fat distribution at different sites including whole body and trunk–locations where there tends to be high correlation at an individual level.

Methods

We performed an analysis of DXA-derived metrics of adiposity (truncal fat %,subtotal fat % and total fat %) from the NHANES database and then correlated the findings with markers of insulin resistance. We analyzed the data from DXA scans in NHANES 1999–2004. Homeostatic model assessment-insulin resistance and HOMA-β (beta-cell function) were estimated. Spearman correlation coefficients were calculated (ρ) between HOMA-IR,HOMA-β and different measures of obesity (Waist circumference(in cm), Body Mass Index (kg/m2), truncal fat %, subtotal fat % as well as total fat %) to gauge the relationship between markers of glucose homeostasis and DXA derived metrics of obesity. We also performed logarithmic transformation of HOMA-IR as well as HOMA-β to ensure normality of distribution and to meet the criteria for regression analysis. A forward selection model (by outcome and gender) was performed to predict log transformed insulin resistance (log HOMA-IR) as well as log transformed HOMA-β (log HOMA-β,measure of beta cell function) from age, serum triglycerides, HDL, trunk fat % and the SBP (in both males and females separately), after reviewing the spearman correlation coefficients.

Results

There were a total of 6147 men and 6369 women who were part of the study cohort. There was a positive correlation between markers of adiposity and log HOMA-IR and log HOMA-β in both males and females.Truncal fat % had the highest nonparametric correlation coefficent with log HOMA-IR among the DXA derived fat% (0.54 in males and 048 in females). In the multivariate analysis, truncal fat % was an independent predictor of logHOMA-IR as well as logHOMA-β. In males, the significant predictors of log HOMA-IR were; age, truncal fat % and HDL cholesterol (Adjusted R square of 0.325 (±0.66), F(3,207) = 34.63, p < .01). In females, the significant predictors of log HOMA-IR were; age, truncal fat %, SBP, Serum triglyceride and HDL cholesterol (Adjusted R square of 0.307 (±0.65),F(5,198) = 18.9, p < .01). In both males and females, the significant predictors of log HOMA-β were; age, and truncal fat % (Males; adjusted R square of 0.25 (±0.63), F (2,208) = 36.4, p < .01, Females; adjusted R square of 0.27 (±0.62), F (2,201) = 38.4, p < .01).

Conclusions

Body fat % on DXA is an imaging biomarker for insulin resistance. Incorporating this important information into DXA acquisitions and reporting frameworks may allow for this information to be available to providers who refer patients for these imaging studies.

Body fat indicators perform better than body mass index in identifying abnormal lipid profiles in boys but not in girls

BACKGROUND

BMI as a body weight indicator, may inadequately represent the biological effect of body fat on lipid profiles. This study aims to assess whether body fat indicators were superior to BMI for recognizing children with dyslipidemia.

METHODS

A nationwide cross-sectional study involving 8944 pediatric participants aged 6-18 years. Measures of fat mass index (FMI), fat mass percentage (FMP), BMI, and four lipid profiles were obtained.

RESULTS

Among boys, the standard multi-linear regression coefficients of FMI for TC, LDL-C, and TG were higher than those of BMI (P < 0.01), but not for HDL-C. Also, the prevalence ratios and area under curves (AUCs) of excess fat classified by FMI for specific abnormal lipid profiles (except for HDL-C) were greater than overweight classified by BMI. The AUCs for detecting children with abnormal TC, LDL-C, and TG of FMI-based excess fat were 3.9%, 5.6%, and 2.8% higher than those of BMI-based overweight, respectively, all P < 0.01. Among girls, the associations of BMI with lipid profiles were substantially similar to FMI. All these results were almost identical when FMP was used instead of FMI.

CONCLUSIONS

DXA measured body fat performs better than BMI in identifying abnormal lipid profiles in boys but not in girls.

Zinc and Insulin Resistance: Biochemical and Molecular Aspects

Studies have shown the participation of minerals in mechanisms involved in the pathogenesis of insulin resistance. Zinc, in particular, seems to play an important role in the secretion and action of this hormone. Therefore, the aim of this review is to understand the role of zinc in increasing insulin sensitivity. We conducted a search of articles published in the PubMed and ScienceDirect database selected from March 2016 to February 2018, using the keywords "zinc," "insulin," "insulin resistance," "insulin sensitivity," and "supplementation." Following the eligibility criteria were selected 53 articles. The scientific evidences presented in this review show the importance of zinc and their carrier proteins in the synthesis and secretion of insulin, as well as in the signaling pathway of action of this hormone. Zinc deficiency is associated with glucose intolerance and insulin resistance; however, the effectiveness of the intervention with the zinc supplementation is still inconclusive.

Assessing truncal obesity in predicting cardiometabolic risk in children: clinical measures versus dual-energy X-ray absorptiometry

AIM

The objectives of this study were to 1) compare the accuracy of waist:hip ratio (WHR) and waist:height ratio (WHtR) by determining their association with reference-standard measures derived from dual-energy X-ray absorptiometry (DXA) and 2) assess the relationship of DXA, WHR and WHtR to measures of dyslipidemia, insulin resistance and inflammation in children.

METHODS

Subjects aged four to 21 were prospectively recruited. Truncal obesity by DXA was defined as the trunk fat:height ratio and trunk fat:nontrunk fat ratio. Three hundred and eight subjects were studied, and 246 (80%) were obese.

RESULTS

There was a strong correlation between WHtR and trunk fat:height (r = 0.84, p < 0.01). DXA measures of truncal obesity had stronger correlations with measures of cardiometabolic risk than WHR and WHtR. Upon multivariable regression, only WHtR had independent associations with cholesterol/HDL, HOMA-IR and high-sensitivity c-reactive protein.

CONCLUSION

WHtR is an accurate measure of truncal obesity. WHtR showed stronger associations with measures of insulin resistance and truncal obesity than WHR.

Sustained impact of the "Healthy Habits, Healthy Girls - Brazil" school-based randomized controlled trial for adolescents living in low-income communities

Pediatric obesity is a major public health concern in low- and middle-income countries, such as Brazil. There is an urgent need for preventive programs for adolescents and, the assessment of their sustained impact. This paper reports the longer-term (6-month post intervention) effects of the "H3G-Brazil" obesity prevention program on weight status and weight-related behaviors. A cluster randomized controlled trial starting with 10 public schools in the city of São Paulo, Brazil involved 253 adolescent girls [mean (se) age = 15.6 (0.87) years]. Body mass index (BMI), waist circumference (WC), dietary intake, physical activity (PA) and sedentary behaviors (SB) were assessed at baseline, immediate post-intervention and 6-month post-intervention (follow-up). ANCOVA was performed using intention to treat principles. There was no effect on BMI, the primary outcome. Although, meaningful increases occurred in waist circumference for both groups, the intervention group presented a lower increase (F = 3.31, p = 0.04). This effect size, however, was lower than the criterion for small (d = 0.102). Unfortunately, significant results favored the control group for time spent on TV/weekdays (F = 5.13, p = 0.01), TV/weekends (F = 5.46, p = 0.01) and sedentary behaviors/weekdays (F = 5.32, p = 0.04). No other significant results were found. This obesity prevention intervention among Brazilian adolescent girls did not have the desire effect on BMI. The significantly lower increase in waist circumference in the intervention groups is inconsistent with the adverse changes detected in sedentary time.