Relationship of body fat and cardiorespiratory fitness with cardiovascular risk in Chinese children

Cardiorespiratory fitness as a mediator between body fat rate and executive function in college students

Purpose

To examine whether body fat rate (BF%) is associated with cardiorespiratory fitness (CRF) and whether cardiorespiratory fitness (CRF) mediates the association between BF% and Executive function (EF) in young adults.

Methods

In this cross-sectional study, 226 college students were recruited from an university. Flanker, 2-back, and odder and shifting tasks were used to assess EF. The incremental cardiopulmonary exercise tests were performed, and maximal oxygen consumption was recorded during test. The body composition measuring instrument was used to evaluate the participants' BF%.

Results

The BF% of college students was negatively correlated with each EF, BF% was negatively correlated with CRF, and CRF was negatively correlated with EF (P< 0.001). Structural equation modeling (SEM) and simultaneous analysis of several groups were used to construct mediator model. The CRF of college students plays a partial mediating role between BF% and EF, and the mediating effect accounts for 48.8% of the total effect value. Sex has no moderate effect on the relationship between BF%, CRF, and EF.

Conclusions

College students with high BF% can improve their CRF by strengthening physical exercise, thereby indirectly improving their EF. Therefore, college students who have a higher body fat percentage should be compensated for engaging in physical exercise in order to enhance their CRF and mitigate the detrimental effects of obesity and overweight on EF.

Associations between cardiorespiratory fitness and cardiometabolic risk factors in children and adolescents with obesity

It is unclear if associations between cardiorespiratory fitness (CRF) and cardiometabolic risk factors are independent of degree of obesity, in children with obesity. The aim of this cross-sectional study on 151 children (36.4% girls), 9-17 years, from a Swedish obesity clinic, was to investigate associations between CRF and cardiometabolic risk factors, adjusted for body mass index standard deviation score (BMI SDS), in children with obesity. CRF was objectively assessed with the Åstrand-Rhyming submaximal cycle ergometer test, and blood samples (n = 96) and blood pressure (BP) (n = 84) according to clinical routine. Obesity specific reference values for CRF were used to create CRF levels. CRF was inversely associated with high-sensitivity C-reactive protein (hs-CRP), independent of BMI SDS, age, sex, and height. The inverse associations between CRF and diastolic BP did not remain significant when adjusted for BMI SDS. CRF and high-density lipoprotein cholesterol became inversely associated when adjusted for BMI SDS. Independent of degree of obesity, lower CRF is associated with higher levels of hs-CRP, as a biomarker of inflammation, in children with obesity and regular assessment of CRF should be encouraged. Future research in children with obesity should investigate if low-grade inflammation decreases when CRF is improved.

Normative values of cardiorespiratory fitness in Croatian children and adolescents

Although defining normative values of cardiorespiratory fitness have been the topic of many Western societies, little evidence has been provided for less developed countries like Croatia. Since cardiorespiratory fitness rapidly declines in Croatian children and adolescents, the newly established normative values would help health-related professionals and physical education teachers to detect 'talented' groups and direct them towards sport and 'risky' groups for planning special interventions. Therefore, the main purpose of the study was to determine normative reference values of cardiorespiratory fitness. A total of 1,612 children and adolescents aged 7-14 years (mean±SD; age 9.7±2.4 years; stature 151.0±17.6 cm; body mass 45.1±19.1 kg; 52.5% girls) participated in this cross-sectional study. Cardiorespiratory fitness was assessed by the Maximal multistage 20-m shuttle run test and the performance was expressed as the number of stages. Maximal oxygen uptake (VO2max) was estimated by equations. Smoothed percentile curves were calculated. Boys outperformed girls in the maximal number of levels achieved after the 20-m shuttle run test and in the VO2max values at each age category. In boys, a gradually higher level of performance between ages 11 and 14 was observed, while in girls the values started to rise after the age of 8. Our study provides one of the first sex- and age-specific normative values for cardiorespiratory fitness assessed by the 20-m shuttle run test in Croatian children and adolescents.

Utility of Adipokines and IL-10 in Association with Anthropometry in Prediction of Insulin Resistance in Obese Children

AIM

This is a case-controlled study, with two hundred children enrolled. They were divided into an obese group of 100 children who had BMI ≥ 95th percentile according to CDC criteria and a group of 100 children with normal weight. All enrolled children were subjected to detailed medical history and clinical examination, in addition to measuring fasting blood sugar, fasting serum insulin, HOMA-IR calculation, lipid profile analysis, total serum cholesterol, low- and high-density lipoproteins (LDL and HDL), and serum triglyceride (TG). Two adipokines (lipocalin-2 and adipsin) serum levels plus IL-10 serum level were assessed.

RESULTS

Higher Z score of weight, MI, and waist/height ratio and high serum cholesterol, LDL, TG, and low HDL were observed in obese children. Higher levels of serum lipocalin-2 and adipsin and lower IL-10 blood level were observed in the obese group in comparison with the normal weight children. Higher insulin resistance index was observed in the obese group, with positive correlation of HOMA-IR with the anthropometric measurements and lipocalin serum level, while negative correlation was observed between IL-10 and fasting insulin in obese children.

CONCLUSION

Simple measurement of general and central adiposity markers and serum lipocalin-2 can predict insulin resistance in obese children while serum adipsin and IL-10 had no association with insulin resistance.

Normative Reference Values and International Comparisons for the 20-Metre Shuttle Run Test: Analysis of 69,960 Test Results among Chinese Children and Youth

There is increasing evidence that cardiorespiratory endurance (CRE) is declining among Chinese children and youth. The 20-meter shuttle run test (20-m SRT) is considered the most effective and widely used field-based measurement of CRE for children and youth worldwide. However, there have been few attempts to set 20-m SRT norms for Chinese children and youth. We aimed to develop sex- and age-specific 20-m SRT norms for Chinese children and youth, and compare them with international standards. Participants were 69,960 healthy children and youth aged 9-17 years from six geographical areas of China, selected using a stratified cluster random sampling method. Sex- and age-specific 20-m SRT percentiles and curves were extracted for four common 20-m SRT metrics (laps, completed stages/minutes, speed at the last complete stage, estimated peak oxygen uptake). We also estimated the prevalence of healthy CRE according to the interim international cut-points (42 mL.kg^-1min^-1 for boys, 35 mL·kg·¹min^-1 for girls). Chinese boys consistently outperformed girls, while more girls (86.4%) exhibited healthy CRE than boys (67.1%). Younger children and youth were more likely to meet the standards compared with the older, regardless of sex. Chinese children and youth underperformed international norms by 0.85% for boys and 3.1% for girls. The performance indicator (z-score) of Chinese children and youth was -0.01, indicating that 20-m SRT performance was worse than the international mean. The sex differences were also higher for international than Chinese students. This study provided national sex- and age-specific 20-m SRT Chinese norms, offering a valuable tool for screening, monitoring and identifying target groups for future interventions and early prevention of cardiovascular risk factors.

Higher Cardiorespiratory Fitness Levels May Attenuate the Detrimental Association between Weight Status, Metabolic Phenotype and C-Reactive Protein in Adolescents-A Multi-Cohort Study

Results from several studies show that only obese, unfit subjects, but not obese, fit subjects, are at higher mortality risk than are normal-weight fit subjects. The aim of the study was two-fold: (1) to examine the differences in C-reactive protein levels across different metabolic phenotypes (healthy and unhealthy) of weight status and (2) ascertain whether high levels of cardiorespiratory fitness (CRF) attenuate the association of C-reactive protein and metabolic phenotypes of weight status. This was a pooled study, which included data from three cross-sectional projects (1706 youth (921 girls) aged 12-18 years). We used a Shuttle run test to assess CRF. Adolescents were classified into six metabolic phenotypes (healthy and unhealthy) of weight status (non-overweight, overweight and obese), based on age- and sex-specific cutoff points for triglycerides, systolic blood pressure, HDL-cholesterol, glucose and body mass index. High-sensitivity assays were used to obtain the C-reactive protein as inflammatory biomarker. After adjustment for potential confounders (age, sex, pubertal stage and country), the analysis of covariance (ANCOVA) shows that C-reactive protein is directly associated with metabolic phenotypes of weight status. Subjects with obesity, regardless of their metabolic profile, had higher levels of C-reactive protein Z-score. In addition, (after adjustments for potential confounders) a two-way ANCOVA showed that high levels of CRF attenuated the associations of C-reactive protein levels in metabolic healthy non-overweight and in adolescents with obesity. In conclusion, higher CRF levels may attenuate the detrimental association between obesity and C-reactive protein independently of metabolic phenotype. Findings from this study are important for prevention, clinical practice on issues associated with adiposity and metabolic disorders.

Independent and Interactive Associations of Fitness and Fatness With Changes in Cardiometabolic Risk in Children: A Longitudinal Analysis

Background: Findings for associations between cardiorespiratory fitness (CRF) and cardiometabolic risk (CMR) factors are inconsistent, and the interactive association between CRF and fatness with CMR factors is unclear in children. Our study aimed to examine whether CRF and fatness are independently and interactively associated with CMR factors. Methods: We included 5,869 children aged 6-13 years in the analysis. Physical examinations, blood tests, and CRF were measured at baseline and 1 year later. Cardiometabolic risk score (CMRS) was computed by summing Z scores of waist circumference (WC), averaged systolic and diastolic blood pressure, glucose, high-density lipoprotein cholesterol (HDL-C, multiplied by -1), and triglycerides. Results: There was a high correlation between fatness and CRF in both boys and girls. High baseline CRF was independently associated with favorable changes in CMRS, BMI, WC, percent body fat (PBF), total cholesterol, LDL-C, and HDL-C (all P < 0.025). Improved CRF was independently associated with favorable changes in CMRS, BMI, WC, PBF, total cholesterol, LDL-C, HDL-C, triglycerides, and fasting glucose (all P < 0.0321). Baseline BMI was positively associated with changes in CMRS, WC, blood pressure, triglycerides, insulin, and HOMA-IR (all P < 0.0462). Low PBF at baseline was associated with favorable changes in CMRS, BMI, WC, blood pressure, HDL-C, triglycerides, insulin, and HOMA-IR (all P < 0.0423). The percentage of the total effect of baseline CRF on changes in CMRS, triglycerides, HDL-C, PBF, and WC mediated by baseline BMI was 66.0, 61.6, 40.3, 20.7, and 9.2%, respectively. Baseline CRF was a significant mediator for the association between baseline BMI and changes in CMRS (mediated by 4.3%), triglycerides (5.1%), and HDL-C (12.0%). An inverse association was found between baseline CRF and CMRS in children with high baseline BMI/PBF only. Improved CRF was associated with decreased BMI and WC in children with low baseline CRF. Conclusions: Fatness and CRF are each independently associated with changes in CMR factors. Fatness is a major mediator for the association between CRF and CMR factors, whereas the association between fatness and CMR factors is also mediated by CRF. The beneficial effect of high CRF on CMR factors was more evident in obese or unfit children.

Continuous cardiometabolic risk score definitions in early childhood: a scoping review

BACKGROUND

Cardiometabolic risk (CMR) in young children has been measured using various approaches, including a continuous summary score that incorporates components such as adiposity, lipids, metabolic factors and blood pressure.

OBJECTIVES

The objective of this study was to comprehensively review definitions of continuous CMR scores in children <10 years of age.

METHODS

A scoping review was conducted using a systematic search of four scientific databases up to June 2016. Inclusion criteria were children <10 years of age and report of a continuous CMR score.

RESULTS

Ninety-one articles were included. Most studies were published from 2007 to 2016 (96%). Nearly all continuous CMR scores (90%) were calculated using the sum or the mean of z-scores, and many articles age-standardized and sex-standardized components within their own population. The mean number of variables included in the risk scores was 5 with a range of 3-11. The most commonly included score components were waist circumference (52%), triglycerides (87%), high-density lipoprotein cholesterol (67%), glucose (43%) and systolic blood pressure (52%).

IMPORTANCE

Continuous CMR scores are emerging frequently in the child health literature and are calculated using numerous methods with diverse components. This heterogeneity limits comparability across studies. A harmonized definition of CMR in childhood is needed.

Parenting matters: Moderation of biological and community risk for obesity

Contributions of parental limit setting, negativity, scaffolding, warmth, and responsiveness to Body Mass Index (BMI) were examined. Parenting behaviors were observed in parent-child interactions, and child BMI was assessed at 5 years of age. Mothers provided demographic information and obtained child saliva samples used to derive cortisol concentration indicators (N = 250). Geospatial crime indices were computed based on publically available information for a subsample residing within the boundaries of a Pacific Northwest city (N = 114). Maternal warmth and limit setting moderated the association between child HPA-axis regulation and BMI. BMI was higher for children at lower cortisol concentrations with greater maternal warmth and lower for youngsters with mid-range cortisol values under high maternal limit setting. Maternal scaffolding moderated the effects of crime exposure, so that lower scaffolding translated into higher child BMI with greater neighborhood crime exposure. These parenting behaviors could be leveraged in obesity prevention/intervention efforts.

ANTHROPOMETRY AND CLUSTERED CARDIOMETABOLIC RISK FACTORS IN YOUNG PEOPLE: A SYSTEMATIC REVIEW

OBJECTIVE

To conduct a systematic review of the literature on the ability of anthropometric indicators to predict clustered cardiometabolic risk factors (CMRF) in children and adolescents.

DATA SOURCE

Studies published from June 1st, 2011 to May 31st, 2016 in the PubMed, SciELO and LILACS databases were analyzed. The research was based on keywords derived from the terms "anthropometric indicators" AND "cardiometabolic risk factors". Observational studies on the ability of anthropometric indicators as predictors of clustered CMRF in children and adolescents in Portuguese, English and Spanish languages were included. Studies with a specific group of obese patients or with other diseases were not included.

DATA SYNTHESIS

Of the 2,755 articles retrieved, 31 were selected for systematic review. Twenty-eight studies analyzed body mass index (BMI) as a predictor of clustered CMRF. Only 3 of the 25 cross-sectional studies found no association between anthropometric indicators and clustered CMRF. The results of six studies that compared the predictive ability of different anthropometric measures for clustered CMRF were divergent, and it was not possible to define a single indicator as the best predictor of clustered CMRF. Only six articles were cohort studies, and the findings suggested that changes in adiposity during childhood predict alterations in the clustered CMRF in adolescence.

CONCLUSIONS

BMI, waist circumference and waist-to-height ratio were predictors of clustered CMRF in childhood and adolescence and exhibited a similar predictive ability for these outcomes. These findings suggest anthropometric indicators as an interesting screening tool of clustered CMRF at early ages.

Aerobic capacity and future cardiovascular risk in Indian community from a low-income area in Cauca, Colombia

Background

Several studies indicates that children’s aerobic capacity levels are predictors of the future risk of non-communicable diseases. Therefore, the aim of this study was to establish the proportion of subjects whose aerobic capacity is indicative of future cardiovascular risk in Indian-Nasa community from a low-income area in Cauca, Colombia.

Methods

We performed a cross-sectional analysis of morphological component (height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat percent [BF%]), and the cardiorespiratory component (course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption by indirect VO₂max) from 576 participants (319 boys and 257 girls) aged 10 to 17.9 years, using the standardized FUPRECOL test battery.

Results

We showed that the boys performed better than the girls in cardiorespiratory fitness. The proportion of subjects with an aerobic capacity indicative of future cardiovascular risk was 7.3%. By sex, 3.8% of boys and 11.7% of girls (X²p = 0.001) displayed an unhealthy aerobic capacity in this study.

Conclusion

The findings of this study that provide the first data on aerobic capacity health for Colombian Nasa Indian children and adolescents aged 10–17.9 years. Although the known loss of aerobic capacity is a serious consequence of the future risk of non-communicable diseases, the deterioration of physical fitness deserves increased attention among indigenous population.

International variability in 20 m shuttle run performance in children and youth: who are the fittest from a 50-country comparison? A systematic literature review with pooling of aggregate results

OBJECTIVES

To describe and compare 20 m shuttle run test (20mSRT) performance among children and youth across 50 countries; to explore broad socioeconomic indicators that correlate with 20mSRT performance in children and youth across countries and to evaluate the utility of the 20mSRT as an international population health indicator for children and youth.

METHODS

A systematic review was undertaken to identify papers that explicitly reported descriptive 20mSRT (with 1-min stages) data on apparently healthy 9-17 year-olds. Descriptive data were standardised to running speed (km/h) at the last completed stage. Country-specific 20mSRT performance indices were calculated as population-weighted mean z-scores relative to all children of the same age and sex from all countries. Countries were categorised into developed and developing groups based on the Human Development Index, and a correlational analysis was performed to describe the association between country-specific performance indices and broad socioeconomic indicators using Spearman's rank correlation coefficient.

RESULTS

Performance indices were calculated for 50 countries using collated data on 1 142 026 children and youth aged 9-17 years. The best performing countries were from Africa and Central-Northern Europe. Countries from South America were consistently among the worst performing countries. Country-specific income inequality (Gini index) was a strong negative correlate of the performance index across all 50 countries.

CONCLUSIONS

The pattern of variability in the performance index broadly supports the theory of a physical activity transition and income inequality as the strongest structural determinant of health in children and youth. This simple and cost-effective assessment would be a powerful tool for international population health surveillance.

Associations among cardiorespiratory endurance, body mass index and blood pressure in Han Chinese children: results from the 2010 Chinese National Survey On Students' Constitution and Health

The associations among cardiorespiratory endurance (CRE), body mass index (BMI) and blood pressure (BP) in children are still unclear. This study aimed to examine the relationships among CRE, BMI and BP in Chinese children. Data were derived from the 2010 Chinese National Survey on Students' Constitution and Health. An endurance run test was used to determine CRE and children were stratified into low and high/moderate CRE groups. BMI was dichotomized into non-overweight and overweight. Among overweight children aged 7-12 years, the risk of high BP (HBP) was significantly higher in the low CRE group than in the high/moderate CRE group (in boys, odds ratio=1.13, 95% confidence interval: 1.03-1.24, P=0.010; in girls, odds ratio=1.18, 95% confidence interval: 1.04-1.33, P=0.010) after adjusting for age, BMI, socioeconomic status and area of residence. However, among all children aged 13-18 years and non-overweight children aged 7-12 years, we did not observe similar results. Higher CRE is associated with lower BP. Overweight children have a significantly higher risk of HBP and low CRE may increase the risk of HBP, independently of BMI, among 7- to 12-year-old overweight children.

International normative 20 m shuttle run values from 1 142 026 children and youth representing 50 countries

OBJECTIVE

To develop sex-specific and age-specific international norms for the 20 m shuttle run test (20mSRT) in children and youth (aged 9-17 years), and to estimate the prevalence meeting the FITNESSGRAM criterion-referenced standards for healthy cardiorespiratory endurance (CRE).

METHODS

A systematic review was undertaken to identify papers explicitly reporting descriptive 20mSRT (with 1 min stages) data on children and youth since 1981. Data were included on apparently healthy (free from known disease/injury) 9-17 years old. Following standardisation to a common metric and for protocol differences, pseudo data were generated using Monte Carlo simulation, with population-weighted sex-specific and age-specific normative centiles generated using the Lambda Mu and Sigma (LMS) method. Sex-related and age-related differences were expressed as per cent and standardised differences in means. The prevalence with healthy CRE was estimated using the sex-specific and age-specific FITNESSGRAM criterion-referenced standards for [Formula: see text].

RESULTS

Norms were displayed as tabulated centiles and as smoothed centile curves for the 20mSRT using 4 common metrics (speed at the last completed stage, completed stages/minutes, laps and relative [Formula: see text]). The final data set included 1 142 026 children and youth from 50 countries, extracted from 177 studies. Boys consistently outperformed girls at each age group (mean difference±95% CI: 0.86±0.28 km/h or 0.79±0.20 standardised units), with the magnitude of age-related increase larger for boys than for girls. A higher proportion of boys (mean±95% CI: 67±14%) had healthy CRE than girls (mean±95% CI: 54±17%), with the prevalence of healthy CRE decreasing systematically with age.

CONCLUSIONS

This study provides the most comprehensive and up-to-date set of international sex-specific and age-specific 20mSRT norms for children and youth, which have utility for health and fitness screening, profiling, monitoring and surveillance.

Dyslipidemia is Associated with Unfit and Overweight-Obese Children and Adolescents

BACKGROUND

Both poor aerobic fitness and obesity, separately, are associated with abnormal lipid profiles.

OBJECTIVE

To identify possible relationships of dyslipidemia with cardiorespiratory fitness and obesity, evaluated together, in children and adolescents.

METHODS

This cross-sectional study included 1,243 children and adolescents (563 males and 680 females) between 7 and 17 years of age from 19 schools. Obesity was assessed using body mass index (BMI) measurements, and cardiorespiratory fitness was determined via a 9-minute run/walk test. To analyze the lipid profile of each subject, the following markers were used: total cholesterol, cholesterol fractions (high-density lipoprotein and low-density lipoprotein) and triglycerides. Data were analyzed using SPSS v. 20.0, via prevalence ratio (PR), using the Poisson regression.

RESULTS

Dyslipidemia is more prevalent among unfit/overweight-obese children and adolescents compared with fit/underweight-normal weight boys (PR: 1.25; p = 0.007) and girls (PR: 1.30, p = 0.001).

CONCLUSIONS

The prevalence of dyslipidemia is directly related to both obesity and lower levels of cardiorespiratory fitness.

Urban-Rural Differences in Cardiovascular Disease Risk Factors: A Cross-Sectional Study of Schoolchildren in Wuhan, China

Background

China’s rapid population growth and urban migration has developed healthcare inequity across the urban-rural divide. Past studies comparing cardiovascular disease (CVD) risk factor prevalence amongst urban-rural Chinese children are sparse and conflicting. We examined the association between urban-rural residence and risk of offspring CVD in Chinese children.

Methods

A cross-sectional study was conducted in Wuhan, China, during May and June 2010. CVD risk factors include; waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), triglycerides (TG), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, body mass index (BMI), cardiorespiratory fitness (CRF), metabolic syndrome (MetS), and metabolic risk score (MRS). Analysis of covariance and multivariable logistic regression were used to estimate associations between urban-rural residence and offspring CVD risks.

Findings

A total of 579 Chinese children (338 boys and 241 girls) aged 9.6 (0.7) years participated in this study. Rural boys had significantly lower CRF and higher FBG, TG, and MRS, while urban boys had significantly higher LDL and DBP. Rural girls had significantly higher BMI, FBG, and TG, as well as lower CRF. Rural children were at increased risks for decreased CRF, elevated MRS, and TG, (OR:2.04, 95%CI:1.29–3.25), (OR:2.33, 95%CI:1.50–3.62), and (OR:2.40, 95%CI:1.62–3.57), respectively. Rural girls and mothers were at increased risks for overweight(OR:7.19, 95%CI:1.64–31.6)/obesity (OR:1.683, 95%CI:1.01–2.82). However, rural boys and fathers were less likely to have overweight(OR:0.62, 95%CI:0.34–1.12)/obesity (OR:0.68, 95%CI:0.48–0.97).

Conclusions

Rural residence was significantly associated with increased CVD risks amongst Chinese children. It is important to provide interventions aiming at China’s urban-rural healthcare inequity and community-based approaches that reduce familial CVD risk.

Physical activity, body composition and metabolic syndrome in young adults

OBJECTIVE

Low physical activity (PA) is a major risk factor for cardiovascular and metabolic disorders in all age groups. We measured intensity and volume of PA and examined the associations between PA and the metabolic syndrome (MS), its components and body composition among young Finnish adults.

RESEARCH DESIGN AND METHODS

The study comprises 991 men and women born 1985-86, who participated in a clinical study during the years 2009-11 which included assessments of metabolism, body composition and PA. Objectively measured (SenseWear Armband) five-day PA data was available from 737 participants and was expressed in metabolic equivalents of task (MET).

RESULTS

The prevalence of MS ranged between 8-10%. Higher total mean volume (MET-hours) or intensity (MET) were negatively associated with the risk of MS and separate components of MS, while the time spent at sedentary level of PA was positively associated with MS.

CONCLUSIONS

MS was prevalent in approximately every tenth of the young adults at the age of 24 years. Higher total mean intensity and volume rates as well as longer duration spent at moderate and vigorous PA level had a beneficial impact on the risk of MS. Longer time spent at the sedentary level of PA increased the risk of MS.

Parental weight status and offspring cardiovascular disease risks: a cross-sectional study of Chinese children

Introduction

Prevalence of childhood obesity in China is increasing, and parental weight is a risk factor for the development of obesity in children. We examined the relationship of parental body weight status with risk of offspring cardiovascular disease (CVD) in Chinese children.

Method

We conducted a cross-sectional study in Wuhan, China, during May and June 2010. Parental body mass index (BMI) was calculated according to self-reported height and weight. Offspring CVD risk factors, including BMI, waist circumference, blood pressure, fasting glucose, triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, cardiorespiratory fitness (CRF), and metabolic risk score (MRS), were assessed through anthropometric measures, blood samples, and a CRF test. Multiple linear regression and analysis of covariance were used to examine the effects of maternal and paternal weight status on offspring CVD risks.

Results

A total of 580 Chinese children (339 boys and 241 girls, mean [standard deviation] age, 9.6 [0.7] years) participated in the study. Maternal BMI was significantly associated with offspring elevated BMI (β = 0.134, P = .002), waist circumference (β = 0.253, P = .04), and decreased CRF (β = −0.134, P = .01). Paternal BMI was significantly associated with elevated offspring BMI (β = 0.161, P < .001), waist circumference (β = 0.404, P < .001), triglycerides (β = 0.017, P = .03), MRS (β = 0.084, P = .03), and decreased CRF (β = −0.174, P < .001). BMI (P < .001), waist circumference (P < .001), and MRS (P < .05) were positively associated with additional overweight/obese parents, whereas CRF was negatively associated (P < .001).

Conclusion

Parental weight status was significantly associated with increased risk of CVD in their children, and the association was stronger for paternal weight status.

[Association of body mass index and aerobic physical fitness with cardiovascular risk factors in children]

Objective:

To identify the association between both, body mass index and aerobic fitness, with cardiovascular disease risk factors in children.

Methods:

Cross-sectional study, carried out in Itaúna-MG, in 2010, with 290 school children ranging from 6 to 10 years-old of both sexes, randomly selected. Children from schools located in the countryside and those with medical restrctions for physical activity were not included. Blood sample was collected after a 12-hour fasting period. Blood pressure, stature and weight were evaluated in accordance with international standards. The following were considered as cardiovascular risk factors: high blood pressure, high total cholesterol, LDL, triglycerides and insulin levels, and low HDL. The statistical analysis included the Spearman's coefficient and the logistic regression, with cardiovascular risk factors as dependent variables.

Results:

Significant correlations were found, in both sexes, among body mass index and aerobic fitness with most of the cardiovascular risk factors. Children of both sexes with body mass index in the fourth quartile demonstrated increased chances of having high blood insulin and clustering cardiovascular risk factors. Moreover, girls with aerobic fitness in the first quartile also demonstrated increased chances of having high blood insulin and clustering cardiovascular risk factors.

Conclusion:

The significant associations and the increased chances of having cardiovascular risk factors in children with less aerobic fitness and higher levels of body mass index justify the use of these variables for health monitoring in Pediatrics.

Obesity as a mediator of the influence of cardiorespiratory fitness on cardiometabolic risk: a mediation analysis

OBJECTIVE

The relationship between cardiorespiratory fitness (CRF) and metabolic syndrome (MetS) is well known, although the extent to which body weight may act as a confounder or mediator in this relationship is uncertain. The aim of this study was to examine whether the association between CRF and cardiometabolic risk factors is mediated by BMI.

RESEARCH DESIGN AND METHODS

A cross-sectional study including 1,158 schoolchildren aged 8-11 years from the province of Cuenca, Spain, was undertaken. We measured height, weight, waist circumference (WC), blood pressure, fasting plasma lipid profile and insulin, and CRF (20-m shuttle run test). A validated cardiometabolic risk index was estimated by summing standardized z scores of WC, log triglyceride-to-HDL cholesterol ratio (TG/HDL-c), mean arterial pressure (MAP), and log fasting insulin. To assess whether the association between CRF and cardiometabolic risk was mediated by BMI, linear regression models were fitted according to Baron and Kenny procedures for mediation analysis.

RESULTS

In girls, BMI acts as a full mediator in the relationship between CRF and cardiometabolic risk factors, with the exception of log TG/HDL-c ratio. In boys, BMI acts as a full mediator in the relationship between CRF and both log TG/HDL-c ratio and MAP, and as a partial mediator in the relationship between CRF and cardiometabolic risk factors.

CONCLUSIONS

BMI mediates the association between CRF and MetS in schoolchildren. Overall, good levels of CRF are associated with lower cardiometabolic risk, particularly when accompanied by weight reduction.

Determinants of metabolic syndrome in Chinese schoolchildren

The objective of this study was to identify the potential risk factors of metabolic syndrome (MetS) among Chinese schoolchildren. A cross-sectional study among 624 children (357 boys and 267 girls, aged 9.6 ± 0.7 years) was conducted in Wuhan, China, from May to June 2010. MetS was defined according to the criteria proposed by De Ferranti and the International Diabetes Federation (IDF) criteria. Data on cardiorespiratory fitness (CRF), household income, parental hypertension, and children's personal information, including birth weight, preterm birth, and breast-feeding, reported by their parents were obtained. Multiple logistic regression showed that CRF (odds ratio [OR] = 0.68; 95% confidence interval [CI] = 0.60-0.77), breast-feeding (OR = 0.32; 95% CI = 0.10-0.97), and paternal hypertension (OR = 5.06; 95% CI = 1.20-21.37) were all independently associated with MetS. In conclusion, low CRF and paternal hypertension significantly increase the risk, whereas breast-feeding may reduce the risk of MetS among Chinese schoolchildren.