"Fat but Fit" Paradox and Cardiometabolic Risk in Children: The Role of Physical Activity.

Background: The "fat but fit" paradigm suggests that high fitness levels counteract the negative consequences of obesity on cardiometabolic risk, nevertheless, this paradigm has been less studied in children. Objectives: To analyze the relationship between "fat but fit" categories and cardiometabolic risk factors in school children, and to examine whether the intensity of physical activity (PA) is related with the fat but fit (FF) category in which the child is classified. Methods: We analyzed the baseline measurements of 312 school children aged 9-11 years involved in the clinical trial MOVI-daFit!, including adiposity parameters (BMI, waist circumference, and body fat mass percentage), cardiorespiratory fitness (CRF), blood pressure parameters, PA, and biochemical parameters (blood lipid profile, insulin, C-reactive protein, and glycosylated hemoglobin). Results: The cluster analysis of body fat mass percentage and VO2 max estimate z-scores agreed with the four categories of the "fat but fit" paradigm: fat unfit (FU), unfat unfit (UU), FF, and unfat fit (UF). Analysis of variance (ANOVA) models indicated that children in the FF and UF clusters had better levels of biochemical parameters [high-density lipoprotein cholesterol (HDL-c), triglycerides (TG), TG/HDL-c, insulin], vigorous PA amount and metabolic syndrome (MetS) index than their peers in the FU and UU cluster categories (p < 0.05). Conclusions: Our results reinforce the "fat but fit" paradigm proving that CRF levels can counteract the effect of obesity on some cardiometabolic risk factors (HDL-c, TG, TG/HDL-c, insulin, PA, and MetS) in school children. ClinicalTrials.gov Identifier: NCT03236337.

Validity of a single-factor model underlying the metabolic syndrome in children: a confirmatory factor analysis.

OBJECTIVE: We used confirmatory factor analysis to test whether a single factor might explain the clustering of the metabolic syndrome (MS) components in children. RESEARCH DESIGN AND METHODS: We studied 1,020 children aged 10-13 years from 20 schools in Cuenca, Spain. The single-factor model included: waist circumference (WC), fasting insulin, triglyceride to HDL cholesterol ratio (Triglyl/HDL-C), and mean arterial pressure (MAP). The standardized scores of the four variables in the model were used to develop a continuous MS index. RESULTS: Factor loadings were 0.67 for WC, 0.68 for fasting insulin, 0.57 for Triglyl/HDL-C, and 0.37 for MAP. The single-factor model also showed a good fit to the data. As compared with Adult Treatment Panel III criteria, the MS index showed strong validity in the diagnosis of MS (area under the receiver operating characteristic curve = 0.98, 95% CI 0.96-0.99). CONCLUSIONS: A single underlying factor has acceptable validity to represent MS in children.

Association of adiposity measures with blood lipids and blood pressure in children aged 8-11 years.

AIM: To examine the association of body mass index (BMI), triceps skinfold thickness (TST) and percentage body fat (%BF) from bioelectrical impedance analysis (BIA) with blood lipids, systolic blood pressure (SBP) and diastolic blood pressure (DBP) in children. METHODS: Cross-sectional study was conducted on 1280 schoolchildren aged 8-11 years from the Cuenca province (Spain). Data collection was conducted under standardized conditions, taking several measurements of each variable to enhance accuracy. Analyses were performed using age-adjusted correlation coefficients, and multiple linear regression adjusted for age, BMI, TST and %BF. RESULTS: Correlations between %BF and apolipoprotein (apo) B, total cholesterol, low-density lipoprotein cholesterol (LDL-c), total cholesterol/HDL-c ratio and DBP were higher than those for BMI and TST. In contrast, the correlations between BMI, and apo A-I and SBP were higher than those for %BF and TST. The results were similar across the sexes. The correlations between each of the three measures of body fatness, and blood lipids and blood pressure were highest in children with greatest BMI and %BF. When analyses were adjusted for the three body fatness measures, %BF showed stronger associations than did BMI or TST with blood lipids and blood pressure, with the exception of apo A-I and SBP, which were more closely associated with BMI. CONCLUSION: %BF from BIA is more strongly associated than either BMI or TST with most of the blood lipid fractions in schoolchildren aged 8-11 years.

Comparison of ultrasonographic cervical length and the Bishop score in predicting successful labor induction.

BACKGROUND: The aim of this study was to compare the performance of the Bishop score and transvaginal ultrasonography to predict successful labor induction, and to estimate the most useful cut-off points for the two methods. METHODS: The five components of the Bishop score were assessed by digital examination and cervical length was measured by transvaginal ultrasonography in 177 women with a single pregnancy, 36-42 weeks of gestation, and a live fetus in cephalic presentation before induction of labor. RESULTS: Multiple regression analysis showed that the Bishop score, cervical length, and parity provided independent contribution in the prediction of the likelihood of delivering vaginally within 60 h. The only component of the Bishop score that was independently predictive of the probability of vaginal delivery within 60 h was station. The best cut-off points for predicting successful induction using receiver operating characteristic curves were 24 mm for cervical length and 4 for the Bishop score. Cervical length was a better predictor than the Bishop score (sensitivity and specificity of 66 and 77% versus 77 and 56%, respectively). Kaplan-Meier survival curves showed that cervical length was the best discriminator of successful induction. CONCLUSION: Measurement of cervical length by transvaginal ultrasonography is a better predictor of success in labor induction with both topical prostaglandin and oxytocin.