Association between BMI z-score and body composition indexes with blood pressure and grip strength in school-age children: a cross-sectional study.

Childhood obesity is linked to diverse health outcomes, including elevated blood pressure (EBP). Emerging evidence showed that excess fat mass (FM) may have a deleterious impact on blood pressure even in normal-weight children. The primary objective of this study was to assess the association between body weight status by BMI z-score and body composition parameters by conventional bioelectrical impedance analysis (BIA) and bioelectrical impedance vector analysis (BIVA). Also, we aimed to explore the performance of BMI z-score, %FM, and FM index (FMI) in discriminating EBP in a sample of school-age Mexican children. Children were classified as having normal weight, overweight or obesity according to WHO criteria for BMI z-score. FMI was considered high when above 75th percentile, and fat free mass index (FFMI) was considered low when below 25th percentile of the reference population. Body composition was also classified according to the BIVA method and EBP was determined when systolic and/or diastolic blood pressure ≥ 90th percentile. BMI z-score groups were compared by Student´s t-test or the Mann-Whitney U test, or by the chi-square test or Fisher exact test. Receiving operating characteristic (ROC) analysis was performed. 61 children were included (52.5% boys, median age 9.8 (25th, 75th percentiles: 8.5, 11.0)) years. High FMI was observed in 32.3% of children with normal weight. Low FFMI was present in 93.5% of children with normal weight and 53.3% of those with overweight/obesity. According to BIVA, 58.1% and 43.3% of children with normal weight and overweight/obesity were classified as having cachexia. All the three adiposity indicators showed significant areas under the ROC curve (AURC) greater than 0.775 for EBP, with the largest one displayed for FM% (0.794). Hight FMI and low FFMI are common in children with normal weight. Identifying deficiency of FFM might be limited by using solely BMI indicators. Cachexia by BIVA was present in a high proportion of children with either normal weight or overweight/obesity. Both BMI z-score and FM (% and FMI) performed well at discriminating EBP, with a numerically greater AURC observed for FM%. Body composition in pediatric population is relevant for identifying body composition abnormalities at early age.

Enteral Docosahexaenoic Acid and Retinopathy of Prematurity: A Randomized Clinical Trial.

BACKGROUND: Retinopathy of prematurity (ROP) is a disorder of the retina of low-birth-weight preterm infants that potentially leads to blindness. Docosahexaenoic acid (DHA), is protective in experimental models, but its administration as part of parenteral nutrition has shown inconsistent results. We test the effect of enteral DHA to prevent ROP and/or severity and to reduce hospital stay. METHODS: This was a double-blind parallel clinical trial. Preterm infants (n = 110; 55 per group) with birth weight <1500 g but ≥1000 g were recruited in a neonatal intensive care unit. Infants were randomized to receive 75 mg of DHA/kg/d (DHA group) or high oleic sunflower oil (control group) for 14 days by enteral feeding. The effect of DHA was evaluated on any stage of ROP, severe ROP (stage ≥3) incidence, and hospital stay. Groups were compared with relative risk (RR) and 95% confidence interval (CI), Fisher's exact test, Student's t-test, or Mann-Whitney U-test, as appropriate. Logistic regression was applied to adjust for confounders. RESULTS: There was no difference between the DHA and control groups in ROP risk (RR for DHA = 0.79; 95% CI, 0.49-1.27; P = 0.33). However, patients who received DHA showed lower risk for stage 3 ROP (RR for DHA = 0.66; 95% CI, 0.44-0.99; P = 0.03). After adjusting for confounders, this decreased risk remained significant (adjusted odds ratio = 0.10; 95% CI, 0.011-0.886; P = 0.04). Hospital stay was similar between groups. CONCLUSION: Enteral DHA may reduce the incidence of stage 3 ROP.

Subtle metabolic alterations in adolescents with obesity and polycystic ovarian syndrome. / Alteraciones metabólicas sutiles en adolescentes con obesidad y síndrome de ovario poliquístico.

Objective: To evaluate the frequency of some subtle metabolic alterations in a group of adolescents with obesity and polycystic ovary syndrome (PCOS). Materials and Methods: A cross-sectional, comparative study was conducted in a group of adolescents with obesity, and characterized as with or without PCOS according with the Rotterdam Consensus. Medical history, anthropometry, gynecologic pelvic ultrasound (to evaluate ovarian volumes, number of antral follicles and endometrial width), as well as serum glucose, insulin, lipoproteins, interleukin-6, tumor necrosis factor alpha, total testosterone, dehydroepiandrosterone, sexual hormones binding globulin, leptin, adiponectin and insulin-like growth factor 1, the free-androgen index, free and available testosterone, and homeostatic model assessment index were calculated. For statistics, mean and standard deviation, or median and ranges were used for description as appropriate. Likewise, Student t-test or Mann-Whitney test were used for comparisons. Results: From a sample of 180 adolescents, 47 attached to selection criteria. Mean age was 13.5 year and Z-score 2.5. Eighty percent of adolescents presented central distribution of body fat and 95% hyperinsulinemia. The more frequent dyslipidemias were hypertriglyceridemia in 57% and hypercholesterolemia in 12.8%; 25.5% of adolescents presented two out of three criteria for polycystic ovary syndrome (PCOS). Body mass index and insulin were correlated with free testosterone, but the multivariate analysis demonstrated that the magnitude of the association was significantly higher in SOP patients. Conclusions: The metabolic alterations detected in obese adolescents with SOP suggest that the clinical manifestations that accompany the syndrome characterize the PCOS as a metabolic disease, which carry important health risks at short, medium and long term. Therefore, they merit intervening actions to prevent, diagnose and provide timing treatment in order to limit the damage in the course of the natural history of PCOS.

Excessive refined carbohydrates and scarce micronutrients intakes increase inflammatory mediators and insulin resistance in prepubertal and pubertal obese children independently of obesity.

BACKGROUND: Low-grade inflammation is the link between obesity and insulin resistance. Because physiologic insulin resistance occurs at puberty, obese pubertal children are at higher risk for insulin resistance. Excessive diets in refined carbohydrates and saturated fats are risk factors for insulin resistance, but calcium, magnesium, vitamin-D, and the omega-3 fatty acids likely protect against inflammation and insulin resistance. OBJECTIVE: To analyze interactions among dietary saturated fat, refined carbohydrates, calcium, magnesium, vitamin D, and omega-3 fatty acids on the risk of inflammation and insulin resistance in a sample of prepubertal and pubertal children. METHODS: A sample of 229 children from Mexico City was analyzed in a cross-sectional design. Anthropometric measurements, 24 h recall questionnaires, and blood samples were obtained. Serum insulin, glucose, calcium, magnesium, 25-OHD3, C-reactive protein, leptin, adiponectin, and erythrocytes fatty acids were measured. Parametric and nonparametric statistics were used for analysis. RESULTS: While mean macronutrients intake was excessive, micronutrients intake was deficient (P < 0.01). Inflammation determinants were central obesity and magnesium-deficient diets. Determinants of insulin resistance were carbohydrates intake and circulating magnesium and adiponectin. CONCLUSIONS: Magnesium-deficient diets are determinants of inflammation, while high intake of refined carbohydrates is a risk factor for insulin resistance, independently of central adiposity.