Possible role of birth weight on general and central obesity in Chinese children and adolescents: a cross-sectional study

Global Prevalence of Overweight and Obesity in Children and Adolescents: A Systematic Review and Meta-Analysis

Importance

Overweight and obesity in childhood and adolescence is a global health issue associated with adverse outcomes throughout the life course.

Objective

To estimate worldwide prevalence of overweight and obesity in children and adolescents from 2000 to 2023 and to assess potential risk factors for and comorbidities of obesity.

Data Sources

MEDLINE, Web of Science, Embase, and Cochrane.

Study Selection

The inclusion criteria were: (1) studies provided adequate information, (2) diagnosis based on body mass index cutoffs proposed by accepted references, (3) studies performed on general population between January 2000 and March 2023, (4) participants were younger than 18 years.

Data Extraction and Synthesis

The current study was performed in accordance with the Meta-analysis of Observational Studies in Epidemiology guidelines. DerSimonian-Laird random-effects model with Free-Tukey double arcsine transformation was used for data analysis. Sensitivity analysis, meta-regression, and subgroup analysis of obesity among children and adolescents were conducted.

Main Outcomes and Measures

Prevalence of overweight and obesity among children and adolescents assessed by World Health Organization, International Obesity Task Force, the US Centers for Disease Control and Prevention, or other national references.

Results

A total of 2033 studies from 154 different countries or regions involving 45 890 555 individuals were included. The overall prevalence of obesity in children and adolescents was 8.5% (95% CI 8.2-8.8). We found that the prevalence varied across countries, ranging from 0.4% (Vanuatu) to 28.4% (Puerto Rico). Higher prevalence of obesity among children and adolescents was reported in countries with Human Development Index scores of 0.8 or greater and high-income countries or regions. Compared to 2000 to 2011, a 1.5-fold increase in the prevalence of obesity was observed in 2012 to 2023. Substantial differences in rates of obesity were noted when stratified by 11 risk factors. Children and adolescents with obesity had a high risk of depression and hypertension. The pooled estimates of overweight and excess weight in children and adolescents were 14.8% (95% CI 14.5-15.1) and 22.2% (95% CI 21.6-22.8), respectively.

Conclusions and Relevance

This study's findings indicated 1 of 5 children or adolescents experienced excess weight and that rates of excess weight varied by regional income and Human Development Index. Excess weight among children and adolescents was associated with a mix of inherent, behavioral, environmental, and sociocultural influences that need the attention and committed intervention of primary care professionals, clinicians, health authorities, and the general public.

The Relationship between Birth Weight and the Risk of Overweight and Obesity among Chinese Children and Adolescents Aged 7-17 Years

Obesity is a major public health issue in children and adolescents. Our study aimed to examine the impacts of birth weight on overweight and obesity among Chinese children and adolescents. Using data from the China National Nutrition and Health Surveillance of Children and Lactating Mothers in 2016-2017, we included 10,041 participants aged 7-17 years. According to birth weight, participants were categorized into six groups, and the birth weight category of 3000 to 3499 g was chosen as the reference group, containing the largest number of children. Logistic regression analyses were used to investigate the association of birth weight with the risk of being obese at 7 to 17 years of age in multivariable-adjusted models. A restricted cubic spline was utilized to show the odds ratios (ORs) of obesity at different birth weight levels. The adjusted ORs for overweight were 0.98 (95%CI 0.63, 1.53), 1.02 (95%CI 0.84, 1.25), 1.34 (95%CI 1.16, 1.55), 1.72 (95%CI 1.35, 2.18), and 1.17 (95%CI 0.71, 1.96) in several birth weight groups, compared with group C (3000-3499 g). The adjusted ORs for obesity were 0.82 (95%CI 0.48, 1.40), 0.77 (95%CI 0.60, 0.98), 1.33 (95%CI 1.13, 1.57), 1.97 (95%CI 1.53, 2.53), and 2.01 (95%CI 1.27, 3.19). Furthermore, children in the post-pubertal stage had a slightly higher risk of overweight and obesity than those in the pre-pubertal and pubertal stage. Moreover, these associations were stronger among boys. The lower part of normal birth weight range is associated with a lower risk of overweight and obesity in children and adolescents. However, higher levels of birth weight increase risk.

Intergenerational relationship between parental famine exposure and offspring's obesity risks

BACKGROUND

The intergenerational relationship between parental famine exposure and the obesity risks of offspring has not been well studied.

METHODS

Using a cohort of 3654 respondents whose parents were born between 1950 and 1964 from the national data of the China Family Panel Studies, this study examines the associations between parental exposure to the 1959-1961 Chinese famine and offspring's body mass index (BMI). A cross-sectional difference-in-difference design was used to estimate the effects of parental famine exposures on offspring's BMI by exploiting temporal variations in the duration and period of famine across the parental birth cohorts between 1950 and 1964, and geographical variations in the famine severity at the province level.

RESULTS

After adjusting individual characteristics and province-level fixed effects, we found that parental famine exposures in the preschool and school-age stages were associated with an increased BMI of offspring while there was not a significant association between prenatal famine exposure and offspring's BMI. The stratified analyses further show that the effects of parental famine exposure did not follow the same trajectory in subgroups.

CONCLUSIONS

Famine experiences of parents were associated with increased BMI of offspring, suggesting an intergenerational impact of severe malnutrition on obesity risks.

The Uterine Environment and Childhood Obesity Risk: Mechanisms and Predictions

PURPOSE OF REVIEW

Childhood obesity is a growing health problem in many populations, hence the urgent need to unravel the underlying mechanisms. Some evidence suggests that exposure to suboptimal intrauterine environments can program foetal metabolic health, with adverse consequences in later life, including susceptibility to childhood obesity.

FINDINGS

Factors such as high and low foetal birth weight, excessive gestational-weight-gain, maternal stress and smoking are all associated with increased risk of childhood obesity in observational studies. Animal models, where both genetic background and the postnatal environment can be carefully controlled, suggest that several different mechanisms, including epigenetic changes, dysregulation of adipose tissue development and programming of appetite, may be key drivers of developmental programming of childhood obesity. However, the influence of genetics and the post-natal environment are much more difficult to disentangle as independent effects in human studies, which are also complicated by low follow-up rates. Suboptimal intrauterine environments interact with maternal and foetal genetics and with the postnatal environment to contribute to the risk of childhood obesity. Maternal metabolic challenges, for example obesity and insulin resistance, contribute to the risk of foetal overgrowth and subsequent adiposity in childhood. To protect the long-term health of populations, research focusing on effective means of identifying and intervening in the transgenerational cycle of childhood obesity is required.

Association of Birthweight with Overweight, Obesity, and Blood Pressure among Adolescents

We investigated the association of birthweight with overweight, obesity, and blood pressure (BP) among adolescents. This cross-sectional study included 857 participants aged 11–17 years from Liangshan, southwest China. Birthweight information was collected from the participants’ parents. The participants’ height, weight, and BP were measured. High birthweight was defined as a value greater than the sex-specific upper quartile. Participants were classified into four groups based on their weight change at birth and adolescence: normal weight at both time points, weight loss, weight gain, and high weight at both time points. High birthweight was positively associated with overweight and obesity in adolescence [odds ratio (95% confidence interval), OR (95% CI): 1.93 (1.33, 2.79)]. Compared with participants with normal weight at both time points, those with high weight at both time points were more likely to have elevated BP in adolescence (OR [95% CI]: 3.02 [1.65, 5.53]), while those with weight loss had similar odds of elevated BP. The sensitivity analysis results did not change significantly when high birthweight was defined alternatively as birthweight > 4 kg. This study showed that the association between high birthweight and elevated BP in adolescence is influenced by current weight.

The joint associations of high birth weight and not having siblings with metabolic obesity phenotype among school-aged children and adolescents: A National Survey in China

OBJECTIVE

Birth weight (BW) and sibling's status are two important indicators of early intrauterine environment and subsequent living environment, but no evidence has emerged on their joint associations on metabolic obesity phenotype. To determine the joint associations between BW and single-child status with childhood metabolic obesity phenotype was our purpose.

METHODS

A cross-sectional assessment of children and adolescents aged 7-18 years was performed in Chinese seven provinces in 2013. We obtained anthropometric, blood pressure and biochemical measurements, and distributed questionnaires covering demographic, neonatal and lifestyle characteristics. The metabolic obesity phenotype was defined by 2018 consensus-based criteria. Logistic regression and restricted cubic spline models were applied to evaluate the associations of BW and metabolic obesity phenotype, and estimate the multiplicative interactions and the combined associations of BW and single-child status with metabolic obesity phenotype.

RESULTS

Of enrolled 12 346 children and adolescents, the prevalence of metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) was 1.96% and 3.03%. There were 8.95% and 4.03% children with high BW or low BW, and 67.55% did not have siblings. High BW was positively associated with MHO (OR = 1.94, 95%CI = 1.28-2.94). Single-child also had increased odds of MHO and MUO (p < 0.05), and it had joint associations with high BW showing 0.85- to 2.58-fold higher odds of MUO and MHO.

CONCLUSIONS

High BW and single-child status have joint positive associations with the subsequent odds of MHO and MUO, which should be jointly prevented through earlier screening and subsequent preventive strategies.

Joint Effects of Prenatal Folic Acid Supplement with Prenatal Multivitamin and Iron Supplement on Obesity in Preschoolers Born SGA: Sex Specific Difference

Prenatal maternal nutrient supplementation has been reported to be associated with offspring obesity, but the reports are inconsistent and have mainly ignored the differences between the total children population and children born small for gestational age (SGA). This study aimed to examine the joint effects of folic acid, iron, and multivitamin supplementation during pregnancy on the risk of obesity in preschoolers born SGA. A total of 8918 children aged 3-6.5 years born SGA were recruited from Longhua District in Shenzhen of China in 2021. Their mothers completed a structured questionnaire about the child's and parents' socio-demographic characteristics, maternal prepregnant obesity, and mothers' prenatal supplementation of folic acid, iron, and multivitamin. In addition, the children's current weight and height were measured by trained nurses. Logistic regression models were used to analyze the associations between prenatal supplementations and the current presence of childhood obesity. After controlling for potential confounders, the results of the logistic regression analysis showed that prenatal supplement of folic acid (OR = 0.72, 95% CI = 0.55~0.93) was associated with a lower likelihood of being an obese preschooler born SGA. In contrast, the ingestion of multivitamin or iron supplements during pregnancy did not seem to be related to the likelihood of childhood obesity in preschoolers born SGA. Moreover, cross-over analysis of prenatal folic acid and multivitamin obtained significant negative associations of prenatal folic acid supplement only (OR = 0.73, 95% CI = 0.55~0.97) and combination supplement of folic acid and multivitamin (OR = 0.67, 95% CI = 0.50~0.90) with obesity of preschoolers born SGA; while the cross-over analysis of prenatal folic acid and iron observed significant negative associations between obesity of preschoolers born SGA and a combination supplement of folic acid and iron (OR = 0.70, 95% CI = 0.52~0.96). Furthermore, the aforementioned significant associations were only found in girls and not in boys when the analyses were stratified by sex. Our findings suggest that the prenatal folic acid supplementation may decrease the risk of obesity in preschool girls born SGA, and that this effect may be modified by prenatal multivitamin or iron supplementation.

Secular trends of birth weight and its associations with obesity and hypertension among Southern Chinese children and adolescents

OBJECTIVES

The association of low or high birth weight (L/HBW) with obesity and hypertension in childhood remains unclear. We aimed to identify the secular trend of birth weight distribution and its relationship to obesity and hypertension in Southern Chinese children and adolescents.

METHODS

6,561 individuals (6-17-year-old) were enrolled by multistage cluster sampling to observed the trend of birth weight distribution and its associated factors. 1,218 were further selected by group matching to investigate the correlation between birth weight and obesity or hypertension.

RESULTS

Between 1997 and 2008, a significant decline in the LBW rate and no significant change in the HBW rate was found. LBW was associated with maternal BMI<18 kg/m² (OR1.79, 95% CI 1.08-2.97) during pregnancy, while maternal BMI between 25.0 and 27.9 kg/m² (OR1.62, 95% CI 1.04-2.52) and paternal BMI>28 kg/m² (OR1.64, 95% CI 1.02-2.63) during pregnancy were associated with HBW. The prevalence of obesity was significantly higher with HBW than normal birth weight (NBW) or LBW (16.73, 6.25 and 5.50%, respectively). The prevalence rates of suspected hypertension were 1.62, 1.25 and 1.49% among LBW, NBW and HBW, respectively (p>0.05). LBW decreased the risks of childhood overweight (OR0.31, 95% CI 0.18-0.54), but had no effect on suspected hypertension. HBW increased the risks of childhood obesity (OR2.19, 95% CI 1.50-3.20), but decreased the risks of suspected hypertension (OR0.22, 95% CI 0.09-0.58).

CONCLUSIONS

HBW was positively associated with childhood obesity, and parental BMIs management might be one of the measurements to control birth weight to lessen childhood obesity.

Risk factors for obesity and overweight in Chinese children: a nationwide survey

OBJECTIVE

This study aimed to analyze a comprehensive set of potential risk factors for obesity and overweight among Chinese children with a full range of ages and with wide geographical coverage.

METHODS

In the Prevalence and Risk Factors for Obesity and Diabetes in Youth (PRODY) study (2017-2019), the authors analyzed 193,997 children aged 3 to 18 years from 11 provinces, autonomous regions, and municipalities that are geographically representative of China. All participants underwent physical examinations, and their caregivers completed questionnaires including dietary, lifestyle, familial, and perinatal information of participants. A multilevel multinomial logistic regression model was used to evaluate the potential risk factors.

RESULTS

Among the actionable risk factors that were measured, higher consumption frequencies of animal offal (odds ratios [OR] for an additional time/day = 0.91, 95% CI: 0.88-0.95, same unit for OR below unless specified otherwise), dairy products (0.91, 95% CI: 0.88-0.94), freshwater products (0.94, 95% CI: 0.91-0.96), staple foods (0.94, 95% CI: 0.92-0.96), and coarse food grain (OR for every day vs. rarely = 0.92, 95% CI: 0.86-0.98) were associated with lower relative risk of obesity. However, higher restaurant-eating frequency (OR for >4 times/month vs. rarely = 1.21, 95% CI: 1.15-1.29) and longer screen-viewing duration (OR for >2 hours vs. <30 minutes = 1.16, 95% CI: 1.10-1.22) were associated with higher relative risk of obesity. Increased exercise frequency was associated with the lowest relative risk of obesity (OR for every day vs. rarely = 0.72, 95% CI: 0.68-0.77).

CONCLUSIONS

Changes in lifestyle and diet of Chinese children may help relieve their obesity burden.

Relationships between intrauterine fetal growth trajectories and markers of adiposity and inflammation in young adults

BACKGROUND

There is now good evidence that events during gestation significantly influence the developmental well-being of an individual in later life. This study aimed to investigate the relationships between intrauterine growth trajectories determined by serial ultrasound and subsequent markers of adiposity and inflammation in the 27-year-old adult offspring from the Raine Study, an Australian longitudinal pregnancy cohort.

METHODS

Ultrasound fetal biometric measurements including abdominal circumference (AC), femur length (FL), and head circumference (HC) from 1333 mother-fetal pairs (Gen1-Gen2) in the Raine Study were used to develop fetal growth trajectories using group-based trajectory modeling. Linear mixed modeling investigated the relationship between adult body mass index (BMI), waist circumference (WC), and high-sensitivity C-reactive protein (hs-CRP) of Gen2 at 20 (n = 485), 22 (n = 421) and 27 (n = 437) years and the fetal growth trajectory groups, adjusting for age, sex, adult lifestyle factors, and maternal factors during pregnancy.

RESULTS

Seven AC, five FL and five HC growth trajectory groups were identified. Compared to the average-stable (reference) group, a lower adult BMI was observed in two falling AC trajectories: (β = -1.45 kg/m², 95% CI: -2.43 to -0.46, P = 0.004) and (β = -1.01 kg/m², 95% CI: -1.96 to -0.05, P = 0.038). Conversely, higher adult BMI (2.58 kg/m², 95% CI: 0.98 to 4.18, P = 0.002) and hs-CRP (37%, 95% CI: 9-73%, P = 0.008) were observed in a rising FL trajectory compared to the reference group. A high-stable HC trajectory associated with 20% lower adult hs-CRP (95% CI: 5-33%, P = 0.011).

CONCLUSION

This study highlights the importance of understanding causes of the unique patterns of intrauterine growth. Different fetal growth trajectories from early pregnancy associate with subsequent adult adiposity and inflammation, which predispose to the risk of diabetes and cardiometabolic disease.

Implications of leg length for metabolic health and fitness

Background and objectives

Several studies have linked longer legs with favorable adult metabolic health outcomes and greater offspring birth weight. A recent Mendelian randomization study suggested a causal link between height and cardiometabolic risk; however, the underlying reasons remain poorly understood.

Methodology

Using a cross-sectional design, we tested in a convenience sample of 70 healthy young women whether birth weight and tibia length as markers of early-life conditions associated more strongly with metabolically beneficial traits like organ size and skeletal muscle mass (SMM) than a statistically derived height-residual variable indexing later, more canalized growth.

Results

Consistent with the 'developmental origins of health and disease' hypothesis, we found relatively strong associations of tibia length-but not birth weight-with adult organ size, brain size, SMM and resting energy expenditure measured by magnetic resonance imaging (MRI), dual-energy X-ray absorptiometry and indirect calorimetry, respectively.

Conclusions and implications

Building on prior work, these results suggest that leg length is a sensitive marker of traits directly impacting metabolic and reproductive health. Alongside findings in the same sample relating tibia length and height-residual to MRI-measured pelvic dimensions, we suggest there may exist a degree of coordination in the development of long bone, lean mass and pelvic traits, possibly centered on early, pre-pubertal growth periods. Such phenotypic coordination has important implications for fitness, serving to benefit both adult health and the health of offspring in subsequent generations.

Prevalence and Correlates of Overweight, Obesity and Physical Activity in Italian Children and Adolescents from Lombardy, Italy

Investigating pediatric overweight and physical activity correlates is essential to design effective preventive programs. We used regional data (Lombardy, northern Italy) from the 2019 survey “OKKio alla Salute” (3093 children aged 8–9 years with measured anthropometric data), and from the 2018 wave of the “Health Behaviour in School-aged Children” survey (2916 adolescents aged 11–15 years with self-reported anthropometric data). In both the surveys, a cluster sampling methodology was used. Unconditional multiple logistic regression models were applied to estimate the odds ratios (OR) and corresponding 95% confidence intervals (CI) of overweight, obesity and poor physical activity. The prevalence of overweight (including obesity) was 22.4% for children aged 8–9 years and 14.4% for adolescents aged 11–15 years. A higher prevalence of overweight was observed among males, children with greater birth weight and those with obese parents. Scant physical activity was higher among females and older adolescents. There was a direct relationship between obesity and increased psychological distress (OR = 2.44; 95% CI: 1.12–5.27) or being victims of bullying (OR = 2.25; 95% CI: 1.17–4.34). Increasing physical activity significantly decreased the frequency of mental health outcomes. Prevention campaigns should be promoted to safeguard childhood physical and psychological wellbeing.

Prematurity and Low Birth Weight in Neonates as a Risk Factor for Obesity, Hypertension, and Chronic Kidney Disease in Pediatric and Adult Age

Low weight at birth may be due to intrauterine growth restriction or premature birth. Preterm birth is more common in low- and middle-income countries: 60% of preterm birth occur in sub-Saharan African or South Asian countries. However, in some higher-income countries, preterm birth rates appear to be increasing in relation to a reduction in the lower threshold of fetal viability. The cutoff is at 22–23 weeks, with a birth weight of approximately 500 g, although in developed countries such as Japan, the viability cutoff described is 21–22 weeks. There is evidence of the long-term consequences of prenatal programming of organ function and its relationship among adult diseases, such as hypertension (HT), central obesity, diabetes, metabolic syndrome, and chronic kidney disease (CKD). Premature delivery before the completion of nephrogenesis and intrauterine growth restriction leads to a reduction in the number of nephrons that are larger due to compensatory hyperfiltration and hypertrophy, which predisposes to the development of CKD in adulthood. In these patients, the long-term strategies are early evaluation and therapeutic interventions to decrease the described complications, by screening for HT, microalbuminuria and proteinuria, ultrasound monitoring, and renal function, with the emphasis on preventive measures. This review describes the effects of fetal programming on renal development and the risk of obesity, HT, and CKD in the future in patients with low birth weight (LBW), and the follow-up and therapeutic interventions to reduce these complications.

Association between parental unhealthy behaviors and offspring's cardiovascular health status: Results from a cross-sectional analysis of parent-offspring pairs in China

BACKGROUND

Cardiovascular health (CVH) in children and adolescents, which might be largely influenced by parental behaviors, may affect the incidence of cardiovascular diseases in adulthood. However, few studies have been conducted to explore the associations between parental behaviors and CVH status of offspring in China.

METHODS

Data were obtained from a cross-sectional survey conducted in Chinese children and adolescents aged 7-18 years old, with a total of 10,043 parent-offspring pairs included. Parental behaviors included moderate to vigorous physical activity (MVPA), dietary behaviors, and weight status. The CVH status of offspring was consulted by The American Heart Association, including seven factors. The associations between parental behaviors and CVH status of offspring were evaluated by multilevel logistic regression. Stratified analyses were conducted to explore the potential modifying influence of sociodemographic factors.

RESULTS

Most of the offspring had five ideal CVH factors; only 21.04% had six to seven ideal CVH factors. Parental unhealthy behaviors were associated with high odds of nonideal CVH status of offspring. Parental overweight/obesity, insufficient MVPA, and unhealthy dietary behaviors could increase the odds of owning one to three ideal CVH factors in offspring, with corresponding odds ratios (ORs) (95% confidence interval) of 1.61 (1.32-1.96), 1.31 (1.10-1.56), and 2.05 (1.43-2.94), respectively. There was a dose-response relationship between parental single unhealthy behavior and the odds of nonideal CVH status in offspring (P-trend < 0.001). Offspring with overweight parents had ORs of 1.25 for nonideal CVH status, compared to offspring with normal-weight parents. Among offspring who had the same number of ideal CVH factors, the cumulative association between unhealthy behaviors of parents and offspring's nonideal CVH status increased if parents had more unhealthy behaviors (P-trend < 0.001).

CONCLUSIONS

Parental overweight/obesity, insufficient MVPA, and unhealthy dietary behaviors were strongly associated with CVH status in offspring. With a cumulative association, more unhealthy parental behaviors were associated with higher odds of offspring's nonideal CVH status, suggesting that targeting parental behaviors might facilitate attainment of improving CVH status of children and adolescents.

Prevalence and associated factors of metabolic body size phenotype in children and adolescents: A national cross-sectional analysis in China

BACKGROUND

Metabolically healthy obesity (MHO) is a group of subjects with overweight/obesity who present a metabolically healthy profile; however, associated factors are complex and are far from completely understood. The aim of the current study was to estimate the prevalence of different metabolic body size phenotypes and investigate the associated factors in Chinese children and adolescents.

METHODS

A cross-sectional survey was conducted of 12,346 children and adolescents aged 7-18 years from seven provinces in China in 2013. Anthropometric, blood pressure, and biochemical measurements were obtained. A multi-component questionnaire covering demographic, neonatal, and lifestyle characteristics was administered. The classification of metabolic body size phenotype based on three definitions was compared. With metabolically healthy with normal weight (MHNW) as a reference group, logistic regression analyses were used to estimate the potential effects of associated risk factors, with adjustment for age, sex, single-child status, and residence area.

RESULTS

The prevalence of MHNW, MHO, metabolically unhealthy with normal weight (MUNW), and metabolically unhealthy overweight/obesity (MUO) phenotype was 68.6%, 2.0%, 26.4%, and 3.0%, respectively. There were 39.3% MHO and 60.7% MUO among obese participants and 72.2% MHNW and 27.8% MUNW among those with normal weight. Compared to cardiometabolic risk factor (CMRF) criteria and metabolic syndrome (MetS) component definition, the application of the 2018 consensus-based definition may identify more children with abnormal cardiovascular risks, independent of weight status. Compared to younger children, older-aged adolescents were positively associated with higher risks of MUNW (odds ratio (OR) = 1.38, 95% CI = 1.27-1.50) and MUO (OR = 1.29, 95% CI = 1.04-1.60), while factors positively associated with MHO were younger age, single-child status, urban residence, high birth weight, prolonged breastfeeding duration, parental overweight/obesity status, long screen time, and less physical activity.

CONCLUSION

There were still a high proportion of children and adolescents at high cardiometabolic risk in China. Our findings reinforce the need for cardiometabolic risk prevention in children and adolescents irrespective of their weight statuses, such as parental educational programs and healthy lifestyle interventions.

Birth weight for gestational age and later cardiovascular health: a comparison between longitudinal Finnish and indigenous Australian cohorts

INTRODUCTION

Small or large birth weight for gestational age has been linked with later cardiovascular disease risk. However, cardiovascular risk markers from childhood to adulthood according to birth weight in diverse longitudinal settings globally have not been extensively studied.

OBJECTIVES

To examine the relationship between birth weight and cardiovascular risk profile from childhood until young adulthood in two geographically and socioeconomically distinct cohorts.

METHODS

Data were derived from two longitudinal birth cohort studies; one from southern Finland (Special Turku Coronary Risk Factor Intervention Project, STRIP) and one from northern Australia comprising Indigenous Australians (Aboriginal Birth Cohort, ABC). The sample included 747 Finnish participants and 541 Indigenous Australians with data on birth weight, gestational age and cardiovascular risk factors (body mass index [BMI]), waist-to-height ratio [WHtR], lipid profile, blood pressure) collected at ages 11, 18 and 25 or 26 years. Carotid intima-media thickness (cIMT) was assessed at age 18 or 19 years. Participants were categorised according to birth weight for gestational age (small [SGA], appropriate [AGA] or large [LGA]). Associations between birth weight category and cardiovascular risk markers were studied using a repeated measures ANOVA.

RESULTS

Higher birth weight category was associated with higher BMI later in life in both cohorts (p=.003 for STRIP and p<.0001 for ABC). In the ABC, higher birth weight category was also associated with higher WHtR (p=.004). In the ABC, SGA participants had lower systolic and diastolic blood pressure than AGA participants (p=.028 for systolic, p=.027 for diastolic) and lower systolic blood pressure than LGA participants (p=.046) at age 25. In the STRIP cohort, SGA participants had lower cIMT than LGA participants (p=.024).

CONCLUSIONS

Birth weight can predict future cardiovascular risk profile in diverse populations. Thus, it needs to be included in targeted public health interventions for tackling the obesity pandemic and improving cardiovascular health worldwide.Key messagesThe strongest association between birth weight and later cardiovascular risk profile was manifested as differences in body mass index in two culturally and geographically distinct cohorts.Foetal growth is a determinant for later cardiovascular health in diverse populations, indicating a need to focus on maternal and foetal health to improve cardiovascular health worldwide.

Obesity determinants among Malaysian 12-year old school adolescents: findings from the HAT study

BACKGROUND

Childhood obesity has been associated with increased odds of adult obesity and co-morbidities in later life. Finding the key determinants may help in designing the most appropriate and effective interventions to prevent obesity. This study aimed to identify the determinants of obesity among school adolescents in a sub-urban state of Malaysia.

METHODS

This cross-sectional study involved 1,404 school adolescents aged 12 years (46% boys and 54% girls). Socio-demographic, dietary and physical activity data were collected using questionnaires whilst body weight and height were measured and body mass index was classified based on WHO BMI-for-age Z-scores cut-off.

RESULTS

A multivariable linear regression model showed that BMI z-score was positively associated with parents' BMI (P<0.001), birth weight (P=0.003), and serving size of milk and dairy products (P=0.036) whilst inversely associated with household size (P=0.022). Overall, 13.1% of the variances in BMI Z-scores were explained by parents' BMI, birth weight, servings of milk and dairy products and household size.

CONCLUSION

This study found important determinants of body weight status among adolescents mainly associated with family and home environmental factor. This evidence could help to form the effective and tailored strategies at the earliest stage to prevent obesity in this population.

Birth weight and body fat mass in adults assessed by bioimpedance in the ELSA-Brasil study

Intrauterine life is a critical period for the development of body fat and metabolic risk. This study investigated associations between birth weight and total and truncal body fat in adults. To do so, we analyzed data on 10,011 adults participating in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) who self-reported birth weight as < 2.5kg, 2.5-4.0kg, or > 4.0kg at baseline (2008-2010) and underwent bioimpedance in the next follow-up visit (2012-2014). Greater mean total and truncal fat mass were seen in those with high birth weight compared with adequate birth weight (p < 0.001) in both sexes (total fat: 25.2 vs. 23.1kg in men and 31.4 vs. 27.7kg in women, and truncal fat: 13.5 vs. 12.4kg in men and 15.9 vs. 14.2kg in women). U-shaped patterns were observed in restricted cubic-spline analyses in the subset of 5,212 individuals reporting exact birth weights, although statistically significant only for those with high birth weight. In the whole sample, in comparing high to adequate birth weight, the latter predicted having a large (> 85 percentile) total and truncal fat mass, respectively: OR = 1.76, 95%CI: 1.37-2.25 (men) and OR = 1.86, 95%CI: 1.42-2.44 (women); OR = 1.68, 95% CI: 1.31-2.16 (men) and OR = 1.73, 95%CI: 1.31-2.28 (women). However, low birth weight predicted having a large (> 85 percentile) % truncal fat only in women (OR = 1.40, 95%CI: 1.03-1.91). In conclusion, in these men and women born in a period in which fetal malnutrition was prevalent, birth weight showed complex, frequently non-linear associations with adult body fat, highlighting the need for interventions to prevent low and high birth weight during pregnancy.

Relationship between rs9939609 FTO polymorphism with waist circumference and body fat is moderated by ponderal index at birth in youth

OBJECTIVE

The goal of this study was to analyze whether the relationship between the rs9939609 polymorphism of the fat mass and obesity-associated gene (FTO) with nutritional status is moderated by the ponderal index (PI) at birth in children and adolescents.

METHODS

A cross-sectional study evaluated 382 schoolchildren aged 6-17 years. Anthropometric variables such as waist circumference (WC), body mass index (BMI) and body fat percentage (BF%) were used to assess nutritional status. Weight and height at birth were used for the PI calculation, which was divided into tertiles (lower, middle and upper). To compare the continuous variables between genotypes of the rs9939609 polymorphism, a recessive model (TT/AT vs. AA) and covariance analysis (ANCOVA) were used.

RESULTS

The AA genotype of the rs9939609 polymorphism was associated with higher WC in schoolchildren born with lower PI (β = 4.40; p = .048). However, for BF%, the genotype association was found in the upper PI tertile (β = 7.35; p = .040).

CONCLUSION

The relationship between WC and BF% with rs9939609 polymorphism (FTO) seems to be moderated by PI at birth. This is an important insight, since the data for intrauterine growth, genetic factors and the presence of obesity in children and adolescents are still contradictory.

Association between birth weight and risk of abdominal obesity in children and adolescents: a school-based epidemiology survey in China

BACKGROUND

Abdominal obesity is becoming an increasingly serious public health challenge in children and adolescents, there remains controversial opinions on birth weight and risk of childhood abdominal obesity. This study aims to assess the association between birth weight and the risk of abdominal obesity in childhood, as well as to compare the associations among different sex and age groups.

METHODS

A total number of 30,486 (15,869 boys and 14,617 girls) participants aged 6-17 years old were included in this study. Participants were classified into five groups according to their birth weight. Waist-to-height ratio (WHtR) was used to define abdominal obesity. Fractional polynomial regression model was used to assess the association between birth weight and WHtR, and a multi-variable logistic regression model was applied to evaluate the risk of abdominal obesity in different birth weight groups.

RESULTS

A J-shaped association was observed between birth weight and WHtR. Compared with birth weight of 2500-2999 g, high birth weight was associated with increased risk of abdominal obesity [OR (95% CI) for 3000-3499 g: 1.12(1.00-1.24); 3500-3999 g: 1.19(1.07-1.34); ≥4000 g: 1.42(1.24-1.62)]. No significant correlation was observed in children with birth weight ≤ 2499 g. Similar patterns were observed across different age groups. Abdominal obesity risk for high birth weight was particularly pronounced in boys compared to girls.

CONCLUSIONS

Birth weight ≥ 3000 g, especially for boys, was associated with an elevated risk of abdominal obesity in childhood and may benefit from intervention to mitigate this risk.

High birth weight and its interaction with physical activity influence the risk of obesity in early school-aged children

BACKGROUND

High birth weight (HBW) is associated with childhood obesity, but with inconsistent results. This study investigated the relationship between HBW and childhood obesity, and further explored the interaction of HBW with behavioral and socio-economic determinants of obesity.

METHODS

This cross-sectional study enrolled 1906 grade-two children of Guangzhou, China, from June to November, 2016. Overweight/obesity corresponded to a body mass index higher than the sex-age-specific criteria. Abdominal obesity was assessed using the sex-specific waist-height ratio cutoffs. The association of HBW with obesity was evaluated in multivariable logistic regression model. The relative excess risk due to interaction (RERI) and the attributable proportion of interaction (AP) indices were used to measure additive interaction, while applying the interaction of OR index for multiplicative interaction assessment.

RESULTS

Children with HBW had an increased risk of overweight/obesity [odds ratio (OR) = 2.42, 95% confidence interval (CI) = 1.56-3.76] compared with those without HBW. Significant additive interaction of HBW with physical activity was found for overweight/obesity [relative excess risk due to interaction (RERI) = 2.69, 95% CI = 0.62-4.75; attributable proportion of interaction (AP) = 0.72, 95% CI = 0.42-1.02]. The HBW children with insufficient activity had higher odds of overweight/obesity compared to the non-HBW children with sufficient activity (OR = 3.75, 95% CI = 2.06-6.83). In addition, we identified a significant interaction of HBW with household income for abdominal obesity (RERI = 1.20, 95% CI = 0.02-2.37; AP = 0.76, 95% CI = 0.16-1.36).

CONCLUSIONS

HBW confers an increased risk for childhood overweight/obesity. Physical activity attenuates the effect of HBW on overweight/obesity, and HBW possibly synergistically interacts with high household income to promote abdominal obesity in childhood.

Accelerated weight gain, prematurity, and the risk of childhood obesity: A meta-analysis and systematic review

The purpose of this systematic review and meta-analysis of the literature was to analyze and evaluate the impact of prematurity and accelerated weight gain on the risk of childhood and adolescent obesity. CINAHL, Embase, PubMed, and Web of Science databases were searched until December 2019 which yielded 19 studies with a total of 169,439 children enrolled were systematically reviewed. The results revealed that preterm infants had a greater likelihood of childhood obesity (defined as BMI ≥95th percentile for age-sex), than term infants (OR = 1.19, 95% CI [1.13, 1.26]). However, no difference of childhood obesity was found between "small for gestational age"(SGA) and "appropriate for gestational age"(AGA) among preterms. Accelerated weight gain (defined as weight gain velocity during first two years after birth) significantly increased the likelihood of subsequent childhood obesity among preterms (aOR = 1.87, 95% CI [1.57, 2.231]). In conclusion, accelerated weight gain at infancy among preterm children may be a critical contributor to obesity in later life. Establishing optimal growth trajectories and timely referral to health care providers may be of clinical importance.

Gut Microbiome Modulation Based on Probiotic Application for Anti-Obesity: A Review on Efficacy and Validation

The growing prevalence of obesity has become an important problem worldwide as obesity has several health risks. Notably, factors such as excessive food consumption, a sedentary way of life, high sugar consumption, a fat-rich diet, and a certain genetic profile may lead to obesity. The present review brings together recent advances regarding the significance of interventions involving intestinal gut bacteria and host metabolic phenotypes. We assess important biological molecular mechanisms underlying the impact of gut microbiota on hosts including bile salt metabolism, short-chain fatty acids, and metabolic endotoxemia. Some previous studies have shown a link between microbiota and obesity, and associated disease reports have been documented. Thus, this review focuses on obesity and gut microbiota interactions and further develops the mechanism of the gut microbiome approach related to human obesity. Specifically, we highlight several alternative diet treatments including dietary changes and supplementation with probiotics. The future direction or comparative significance of fecal transplantation, synbiotics, and metabolomics as an approach to the modulation of intestinal microbes is also discussed.

Relationship between Children's Birth Weight and Birth Length and a Risk of Overweight and Obesity in 4-15-Year-Old Children

Background and Objectives. The purpose of the study was to investigate the relationship between children’s birth weight/length and a risk of overweight and obesity. Materials and Methods. The study involved 747 children from kindergartens, as well as primary and middle schools from southeastern Poland. All the subjects were examined on fasting status. Each child was examined for body mass and height, in order to calculate their body mass index (BMI), and BMI centile. The parents completed a questionnaire related to basic information about the child and the family. Results. In the study group, the male infants presented greater birth body weight and birth body length. A comparison of the distribution of birth weights and lengths between the children with normal BMI and with high BMI showed statistically significant differences only in the case of birth length of 12–15-year-old children and in the group of boys aged 12–15 years. In the case of the female children and the group of 7–11-year-olds a statistically significant difference was found in the BMI centile at a later age—a higher centile was found in the girls and in the children aged 7–11 years classified as adequate for gestational age (AGA). Conclusions. Birth body weight is positively related to BMI centile; however, no significant differences were found in birth weight between children with overweight/obesity and children with normal body weight. Birth length is associated with a lower BMI centile only in boys aged 12–15 years, and lower birth length is found in boys with overweight and obesity.

From conception to infancy - early risk factors for childhood obesity

Maternal lifestyle during pregnancy, as well as early nutrition and the environment infants are raised in, are considered relevant factors for the prevention of childhood obesity. Several models are available for the prediction of childhood overweight and obesity, yet most have not been externally validated. Moreover, the factors considered in the models differ among studies as the outcomes manifest after birth and depend on maturation processes that vary between individuals. The current Review examines and interprets data on the early determinants of childhood obesity to provide relevant strategies for daily clinical work. We evaluate a selection of prenatal and postnatal factors associated with child adiposity. Actions to be considered for preventing childhood obesity include the promotion of healthy maternal nutrition and weight status at reproductive age and during pregnancy, as well as careful monitoring of infant growth to detect early excessive weight gain. Paediatricians and other health-care professionals should provide scientifically validated, individual nutritional advice to families to counteract excessive adiposity in children. Based on systematic reviews, original papers and scientific reports, we provide information to help with setting up public health strategies to prevent overweight and obesity in childhood.

Metabolic Syndrome and Its Associated Early-Life Factors among Chinese and Spanish Adolescents: A Pilot Study

Metabolic syndrome (MetS) is a growing problem worldwide in adolescents. This study compared two sample populations of young people in Spain and China, and analyzed the association of birth weight and breastfeeding duration with MetS. A cross-sectional study was conducted in adolescents (10–15 years old); 1150 Chinese and 976 Spanish adolescents. The variables analyzed were anthropometric characteristics, biochemical markers, and demographic characteristics using the same methodology and data collection protocol. Also, birth weight and breastfeeding were retrospectively analyzed during the first year of life. The results showed statistically significant differences between the two groups in reference to body mass index (BMI), blood pressure, triglyceride, glucose, and high-density lipoprotein cholesterol (HDL-C) levels. The MetS prevalence was higher in Spanish adolescents (2.5%) than in the Chinese group (0.5%). Breastfeeding duration was inversely associated with hypertriglyceridemia, low HDL-C, and MetS, whereas higher birth weight was associated with hyperglycemia, low HDL-C, hypertriglyceridemia, and abdominal obesity. Spanish adolescents showed more altered MetS components, and consequently, a higher MetS prevalence than the Chinese adolescents. This made them more vulnerable to cardiometabolic risk. Our results highlight the need for interventions designed by health professionals, which would encourage pregnant women to breastfeed their children.

Intrauterine growth restriction and overweight, obesity, and stunting in adolescents of indigenous communities of Chiapas, Mexico

BACKGROUND/OBJECTIVES

Intrauterine growth restriction (IUGR) and low-birth-weight (LBW) are determinant factors in the development of metabolic diseases in children and adolescents. To estimate the magnitude of the association between LBW and IUGR with stunting or obesity among adolescents of two indigenous regions of the southern State of Chiapas, Mexico.

SUBJECTS/METHODS

We assessed a random sample of 303 adolescents selected from a birth cohort study (2003) conducted in three hospitals serving urban and rural communities of Tzotzil-Tzeltal and Selva regions of Chiapas, Mexico. Sociodemographic and anthropometric data from a sample of adolescents were correlated with their anthropometric data at birth (weight, length for age). Logistic regression models were fitted to estimate odds ratios (OR) with 95% confidence intervals to measure the magnitude of the association among the variables of interest. Models were adjusted for potential confounders.

RESULTS

In all, 12% of the sample had LBW and 28.8% IUGR. In total, 29% of adolescents were overweight/obese and 21% were stunted. We found a statistically significant association between IUGR and a lower risk of being overweight/obese. A higher probability for stunting was observed for LBW and IUGR.

CONCLUSIONS

Stunting and overweight/obesity prevalence in this population of adolescents was high and was associated with IUGR.

Association of high birth weight with overweight and obesity in Chinese students aged 6-18 years: a national, cross-sectional study in China

BACKGROUND

The prevalence of childhood overweight and obesity in China has drastically increased 57 times over the past 30 years, and to control birth weight is an effective way to reduce the risk of overweight and obesity across the life course.

OBJECTIVE

This paper aimed to evaluate the association of high birth weight (HBW) with overweight and obesity in Chinese students aged 6-18 years.

METHODS

All students with HBW (n=4981) aged 6-18 years were selected from a cross-sectional survey from seven provinces of China, and 4981 other students with normal birth weight (NBW) were randomly sampled with matched gender, age and province. Anthropometric parameters were measured and characteristics were collected by questionnaires. Multiple logistic regression was used to estimate the OR of overweight and obesity with HBW, unadjusted and adjusted for confounding factors.

RESULTS

Participants with HBW revealed higher body mass index in childhood. The prevalence of overweight and obesity was significantly higher in the HBW group than in the NBW group (overweight 15.3% vs 13.1%, p<0.05; obesity 16.9% vs 10.6%, p<0.05), and the results were similar for overweight in all age groups except age 6-7, age 14-15 and age 16-18. Additionally, HBW was positively associated with overweight (OR=1.230; 95% CI 1.056 to 1.432) and obesity (OR=1.611; 95% CI 1.368 to 1.897) after adjustment for covariates.

CONCLUSIONS

HBW leads to an increased risk of overweight and obesity in childhood; thus, measures to control birth weight, such as controlling gestational weight gain, should be taken from the earliest beginning of life.

TRIAL REGISTRATION NUMBER

NCT02343588; Post-results.

Sports participation and adiposity do not mediate the relationship between birth weight and arterial thickness in adolescents: ABCD Growth Study

OBJECTIVE

To analyse the relationship of altered birth weight with metabolic and cardiovascular outcomes among adolescents, as well as to identify if sports participation is able to attenuate or even eliminate the impact of birth weight on health outcomes.

METHODS

Cross-sectional study (Analysis of Behaviours of Children During Growth [ABCD Growth Study]). Adolescents with age ranging from 11 to 18 years old (14.7±2.1) stratified according to normal (n = 230) and altered (n = 35) birth weight composed the sample. Birth weight was self-reported by adolescent's parents. Sports participation was assessed by face-to-face interview. Carotid intima-media thickness (CIMT) and femoral intima-media thickness (FIMT) were measured using an ultrasound device. C-reactive protein levels were used to assess the inflammatory status. Blood pressure, Z score of metabolic risk (dyslipidemia and glucose), adiposity, and insulin resistance were covariates.

RESULTS

In the crude model, FIMT (p value = 0.037) and C-reactive protein (p value = 0.029) were affected by altered birth weight. In the adjusted models, altered birth weight affected FIMT (p value = 0.048; small effect size of 1.7%), independently of sports participation. For C-reactive protein, previous time of engagement in sports (p value = 0.001; small effect size of 4.8%) affected C-reactive protein, independently of birth weight.

CONCLUSION

Vascular structure seems to be affected by birth weight in adolescents, while its impact on inflammation seems to be attenuated by the regular engagement in sports.

Association between Characteristics at Birth, Breastfeeding and Obesity in 22 Countries: The WHO European Childhood Obesity Surveillance Initiative - COSI 2015/2017

BACKGROUND

In Europe, although the prevalence of childhood obesity seems to be plateauing in some countries, progress on tackling this important public health issue remains slow and inconsistent. Breastfeeding has been described as a protective factor, and the more exclusively and the longer children are breastfed, the greater their protection from obesity. Birth weight has been shown to have a positive association with later risk for obesity.

OBJECTIVES

It was the aim of this paper to investigate the association of early-life factors, namely breastfeeding, exclusive breastfeeding and birth weight, with obesity among children.

METHOD

Data from 22 participating countries in the WHO European COSI study (round 4: 2015/2017) were collected using cross-sectional, nationally representative samples of 6- to 9-year-olds (n = 100,583). The children's standardized weight and height measurements followed a common WHO protocol. Information on the children's birth weight and breastfeeding practice and duration was collected through a family record form. A multivariate multilevel logistic regression analysis regarding breastfeeding practice (both general and exclusive) and characteristics at birth was performed.

RESULTS

The highest prevalence rates of obesity were observed in Spain (17.7%), Malta (17.2%) and Italy (16.8%). A wide between-country disparity in breastfeeding prevalence was found. Tajikistan had the highest percentage of children that were breastfed for ≥6 months (94.4%) and exclusively breastfed for ≥6 months (73.3%). In France, Ireland and Malta, only around 1 in 4 children was breastfed for ≥6 months. Italy and Malta showed the highest prevalence of obesity among children who have never been breastfed (21.2%), followed by Spain (21.0%). The pooled analysis showed that, compared to children who were breastfed for at least 6 months, the odds of being obese were higher among children never breastfed or breastfed for a shorter period, both in case of general (adjusted odds ratio [adjOR] [95% CI] 1.22 [1.16-1.28] and 1.12 [1.07-1.16], respectively) and exclusive breastfeeding (adjOR [95% CI] 1.25 [1.17-1.36] and 1.05 [0.99-1.12], respectively). Higher birth weight was associated with a higher risk of being overweight, which was reported in 11 out of the 22 countries. Bulgaria, Croatia, France, Italy, Poland and Romania showed that children who were preterm at birth had higher odds of being obese, compared to children who were full-term babies.

CONCLUSION

The present work confirms the beneficial effect of breastfeeding against obesity, which was highly increased if children had never been breastfed or had been breastfed for a shorter period. Nevertheless, adoption of exclusive breastfeeding is below global recommendations and far from the target endorsed by the WHO Member States at the World Health Assembly Global Targets for Nutrition of increasing the prevalence of exclusive breastfeeding in the first 6 months up to at least 50% by 2025.

Associations between birth weight, obesity, fat mass and lean mass in Korean adolescents: the Fifth Korea National Health and Nutrition Examination Survey

OBJECTIVE

Previous studies on the relationship between birth weight and obesity in adolescents have mostly been conducted within Western populations and have yielded inconsistent results. We aimed to investigate the association between birth weight, obesity, fat mass and lean mass in Korean adolescents using the fifth Korea National Health and Nutritional Examination Survey (KNHANES V).

METHODS

The study population consisted of a total of 1304 (693 men and 611 women) participants aged between 12 and 18 years. Adjusted ORs and 95% CIs were calculated by multivariable logistic regression analyses to determine the association between birth weight and being overweight or obese. Furthermore, adjusted mean values for body mass index (BMI), fat mass index (FMI) and lean mass index (LMI) according to birth weight were calculated by multiple linear regression analyses.

RESULTS

Individuals within the highest 25th percentile in birth weight were more likely to be overweight (adjusted OR (aOR) 1.75, 95% CI 1.11 to 2.76) compared with adolescents within the 25th and 75th percentile in birth weight. Female adolescents who were in the highest 25th percentile in birth weight were more likely to be obese (aOR 2.13, 95% CI 1.03 to 4.41) compared with those within the 25th and 75th percentile in birth weight. Increasing FMI, but not LMI was associated with increasing birth weight (P for trend: 0.03). This tendency remained only in female population in sex-stratified analysis (P for trend: 0.03).

CONCLUSIONS

High birth weight may lead to obesity and increased fat mass, but not lean mass. Adolescents born with high birth weight may benefit from close weight monitoring and early intervention against obesity.

Paediatric type 2 diabetes in China-Pandemic, progression, and potential solutions

China is gradually taking its place as one of the world's economic giants and concurrently learning to cope with the burden of diseases that are more common in the developed world, such as paediatric type 2 diabetes mellitus. The prevalence of type 2 diabetes has been recently observed among children and adolescents in China; hence, there is a lack of information about the incidence, prevalence, pathogenesis, and pathophysiology of the disease. Diagnosis, treatment, and management have been standardized to a large degree, but there is still a need for data regarding optimal management protocols and how to achieve the best control over current state of the disease. The objective of this review is to consolidate the available information about paediatric diabetes, with a focus on the increasing prevalence of type 2 diabetes in Chinese youth. Here we emphasize the prevention strategies and have included literature with respect to pathogenesis, diagnosis, and treatment published in English and Chinese within the past 10 years.

Developmental origins of health and disease: a new approach for the identification of adults who suffered undernutrition in early life

BACKGROUND

Undernutrition in early life (UELife) is a condition associated with greater occurrence of chronic diseases in adulthood. Some studies on this relationship have used short stature as indicator of UELife. However, other non-nutritional factors can also determine short stature. Depending on the severity of UELife, the human body reacts primarily compromising weight and length gain, but prioritizing brain growth, resulting in disproportionate individuals. Based on this premise, this study aimed to validate a new anthropometric indicator of UELife.

DESIGN

Using stature and head circumference data from a probabilistic sample of 3,109 women, the Head-to-Height Index was calculated: HHI = (head × 2.898)/height. A HHI >1.028 (75th percentile) was the best cutoff for predicting obesity (best balance between sensitivity/ specificity, largest area under the receiver operating characteristic curve, and highest correlation coefficient) and was used to define the condition of body disproportionality. The strength of associations with several outcomes was tested for both disproportionality and short stature (height ≤25th percentile: 153.1 cm).

RESULTS

In adjusted analysis for confounding factors (age, smoking, and education level), the strength of the associations between body disproportionality and the analyzed outcomes was greater than that observed when short stature was used. Respectively, the observed prevalence ratios (95% CI) were (P<0.05 for all comparisons): obesity: 2.61 (2.17-3.15) vs 1.09 (0.92-1.28); abdominal obesity: 2.11 (1.86-2.40) vs 1.42 (1.27- 1.59); high blood pressure: 1.24 (1.02-1.50) vs 0.90 (0.75-1.08); hypercholesterolemia: 2.98 (1.47-6.05) vs 1.65 (0.91-2.99); and hypertriglyceridemia: 1.47 (1.07-2.03) vs 0.91 (0.69-1.21).

CONCLUSION

Body disproportionality is a more accurate indicator of UELife than short stature. While short stature may be genetically determined, a high HHI is due to metabolic adaptations to undernutrition in early life.

Association of birth weight with abdominal obesity and weight disorders in children and adolescents: the weight disorder survey of the CASPIAN-IV Study

Introduction: This study aims to evaluate the association of birth weight (BW) with weight disorders in a national sample of Iranian pediatric population. Methods: This nationwide survey was conducted among 25000 student's aged 6-18 year-old students, who were selected using multistage cluster random sampling from 30 provinces of Iran in 2011-2012. Anthropometric measures were measured under standard protocols by using calibrated instruments. Abdominal obesity was defined based on waist circumference (WC) ≥90th percentile value for age and sex. The WHO criterion was used to categorize BMI. Students' BW was asked from parents using validate questionnaire and was categorized as low BW (LBW) (BW <2500 g), normal BW (NBW) (BW: 2500-4000 g) and high BW (HBW) (BW>4000 g). Results: This national survey was conducted among 23043 school students (participation rate: 92.6%). The mean age of participants (50.8% boys) was 12.54 ± 3.31 years. Results of multivariate logistic regression show that LBW increased odds of underweight (OR [odds ratio]: 1.61; 95% CI: 1.37, 1.89) and students with HBW had decreased odds of underweight (OR: 0.74; 95% CI: 0.58, 0.93) compared to students with NBW. Students with LBW compared to student with NBW had decreased odds of overweight (OR: 0.83; 95% CI: 0.69, 0.98) and general obesity (OR: 0.73; 95% CI: 0.56, 0.95). On the other hand, HBW increased odd of overweight (OR: 1.28; 95% CI: 1.09, 1.50), generalized obesity (OR: 1.59; 95% CI: 1.29, 1.96) and abdominal obesity (OR: 1.29; 95% CI: 1.11, 1.49) compared to NBW group. Conclusion: BW is a determinant of weight disorders and abdominal obesity in childhood and adolescence. This finding underscores the importance of prenatal care as well as close monitoring of the growth pattern of children born with low or high BW.

Incorrect inference in prevalence trend analysis due to misuse of the odds ratio

Because public health agencies usually monitor health outcomes over time for surveillance, program evaluation, and policy decisions, a correct health outcome trend analysis is vital. If the analysis is done incorrectly and/or results are misinterpreted, a faulty trend analysis could jeopardize key aspects of public health initiatives such as program planning, implementations, policy development, and clinical decision making. It is essential then that accurate health outcome trend analysis be implemented in any data-driven decision-making process. Unfortunately, there continues to be common statistical mistakes in prevalence trend analysis. In this article, using recently published results from the Pediatric Nutrition Surveillance System, we will show the effect that an incorrect trend analysis and subsequent interpretation of results can have. We will also propose more appropriate statistical processes, such as the log-binomial model, for these situations.