Poor Skeletal Robustness on Lower Extremities and Weak Lean Mass Development on Upper Arm and Calf: Normal Weight Obesity in Middle-School-Aged Children (9 to 12)

Whole-body bone mineral density and markers of bone homeostasis in adults with normal-weight obesity

Background

Normal-weight obesity (NWO) describes individuals with a normal body mass index (BMI), but high body fat percent. NWO are at-risk for cardiometabolic diseases, but little is known about their bone health.

Methods

Adults (N = 24) were classified as NWO (n = 12; 5M/7F) or low body fat percent controls (Con; n = 12; 6M/6F). Body composition and whole-body bone mineral density (BMD) were assessed using DXA. A serum bioplex assay was performed to examine markers related to bone formation and resorption.

Results

In addition to higher body fat percent and visceral fat, NWO had lower whole-body BMD relative to Con (p's < 0.05). Circulating leptin was higher in NWO than Con (p < 0.05). Two biomarkers generally associated with lower bone mass - sclerostin and parathyroid hormone - were higher in NWO compared to Con (p's < 0.05).

Conclusion

In this preliminary study, adults with NWO displayed lower whole-body BMD alongside evidence of bone resorption. Impaired bone health may be another subclinical risk factor present in NWO.

Assessment of a consensus definition of obesity and metabolic health phenotypes in children at different pubertal stages

Not all individuals with obesity develop metabolic complications, which has brought about the concepts of metabolically healthy and unhealthy obesity (MHO/MUO). However, inconsistent definitions of these conditions have limited their understanding. We assessed whether a recently-proposed consensus definition for MHO/MUO correlates with adiposity and reflects metabolic risk parameters during puberty. Low-middle income children from the Growth and Obesity Cohort Study (Santiago, Chile) were included (n = 949; 1692 visits at Tanner (T)2, T4 and/or one-year post menarche (1YPM)). Anthropometry, body composition and metabolic parameters were compared between MUO and MHO, and also in children without obesity. The risk for presenting MUO phenotype was significantly elevated with higher waist-height ratio (T2), zBMI (T2, T4), trunk fat, and C-reactive protein (T4). Elevated cardiometabolic indices were important predictors of the "unhealthy" phenotype allocation in children with or without obesity. Our observations suggest that the consensus definition in children at T2, T4 and 1YPM reflects metabolic risk and central obesity. Metabolic health phenotype allocation by this equation enables easy detection of risk factors that call for action to prevent long-term metabolic derangements in children with obesity and, importantly, also those without obesity.

Anthropometric parameters to estimate body frame size in children and adolescents: A systematic review

OBJECTIVE

To determine the most frequently body frame size (BFS) measurement and to compare the cut-off values used for classifying body size in children and adolescents.

METHODS

This systematic review focused on primary studies and scientific reports published in Medline Ovid, EMBASE, Web of Science, or Scopus between January 1, 2007 and March 31, 2021. Eligible studies must have included at least one BFS parameter measured in healthy children or adolescents. A descriptive analysis and graphic comparison were performed when values of the body frame were available.

RESULTS

A total of 26 studies involving 317 202 children and adolescents from all over the world were included. The report of Frame index predominated (46%). It was followed by the biacromial diameter single or combined with the bitrochanteric and biiliocristal diameter (27%), the wrist circumference (19%), and the grant index (12%). Fourteen studies reported percentile values of the BFS measurement, but only four presented cut-off values.

CONCLUSIONS

There was no unified BFS measurement in children and adolescents neither reference cut-off values for categorization. The Frame index was the most frequently used. It is difficult to compare BFS statistics due to the diversity of measurements. It is necessary to standardize the use of the methods for measuring BFS.

Normal weight obesity and unaddressed cardiometabolic health risk-a narrative review

Normal weight obesity (NWO) is defined as having a normal body mass index (BMI), but a high body fat mass. There is growing interest in individuals with NWO, which is an underdiagnosed and understudied group, because of their increased risk for cardiometabolic morbidity and mortality. In this review, we summarized the definition, prevalence, etiology, pathophysiology, and cardiovascular outcomes seen in NWO. We have also summarized the available literature on interventions for NWO. There is a wide variation in the body fat percent cutoffs used to diagnose excess body fat. Hence, the prevalence rates of NWO vary between different populations and studies. It is estimated that about 30 million Americans have NWO and the worldwide prevalence ranges from 4.5% to 22%. Genetics, diet, and physical activity are related to NWO. However, etiological factors are not clear. Changes in body composition, inflammation, oxidative stress are present in NWO in comparison to normal weight lean (NWL) who have a normal BMI and normal body fat amount. Furthermore, cardiometabolic changes are observed and some are subclinical. Thus, screening for NWO will enhance the primary prevention of cardiovascular disease. Due to the use of various body fat percent cutoffs and methods to measure body fat, it is challenging to compare between studies. Researchers working in this field should ideally work towards developing standard body fat percent cutoffs for diagnosing NWO. There are many gaps in the literature on NWO unlike for overt obesity and future studies should explore the etiology, molecular mechanisms, and adipose tissue changes of NWO as well as conduct well planned and executed randomized controlled trials testing dietary, physical, and behavioral interventions for NWO in both males and females of different racial and age groups.

Insufficient Physical Fitness and Deficits in Basic Eating Habits in Normal-Weight Obese Children Are Apparent from Pre-School Age or Sooner

Normal-weight obesity appears to be an extended diagnosis/syndrome associated with insufficient physical fitness levels and inadequate eating habits at least from school years. However, its relation to long term health parameters in pre-school children remains unknown, even though pre-school age is crucial for the determining healthy lifelong habits. Therefore, the aim of the current study was to investigate the differences in physical fitness level and basic eating habits between normal-weight obese, normal-weight non-obese, and overweight and obese preschoolers. The research sample consisted of 188 preschoolers aged 4.0–6.9 years (M_age = 5.52 ± 0.8 year), normal-weight obese = 25; normal-weight non-obese = 143, overweight and obese = 20. Body composition was measured using bio-impedance InBody230. Six tests assessed the physical fitness level: sit-ups; standing long jump; shuttle running 4 × 5 meters; throwing with a tennis ball; multistage fitness tests; sit and reach. A four-item eating habits questionnaire for parents focusing on breakfast regularity, consumption of sweet foods and drinks, selection of food and attitude towards eating was used. A non-parametric analysis of variance and Fisher’s exact test along with suitable effect sizes were used for data processing of physical fitness tests and the basic eating habits questionnaire, respectively. Normal-weight obese children performed significantly worse (from p = 0.03 to p < 0.001, ES ω2-G = low to medium) in muscular fitness, cardiorespiratory fitness and running agility compared to normal-weight non-obese counterparts and did not significantly differ in the majority of physical fitness performance tests from overweight and obese peers. In basic eating habits, normal-weight obese boys preferred significantly more sweet foods and drinks (p = 0.003 ES = 0.35, large), while normal-weight obese girls had significantly more negative attitude towards eating (p = 0.002 ES = 0.33, large) in comparison to their normal-weight non-obese peers. Normal-weight obesity seems to develop from early childhood and is associated with low physical fitness and deficits in eating habits which might inhibit the natural necessity for physically active life from pre-school age or sooner.

The prevalence of aberrations in body composition in pediatric cystic fibrosis patients and relationships with pulmonary function, bone mineral density, and hospitalizations

BACKGROUND

Body mass index (BMI) correlates with clinical outcomes in cystic fibrosis but has limitations.  Body composition aberrations in CF are multifactorial. We sought to evaluate body composition and relationships with pulmonary function, bone health, and hospital admissions. Other aims included defining body composition indices in a cohort of children with CF.

METHODS

We conducted a retrospective review of patients with CF, age 8-18 years, seen at Nationwide Children's Hospital (2015-2020). Indices of body composition measured by dual-energy x-ray absorptiometry(DXA) scans.  Data included fat mass, fat-free mass (FFM), forced expiratory volume in one second (FEV1%), bone mineral density (BMD), and hospital admissions. NWA was defined as BMI 5^th-85^th percentile, body fat percentage >85^th percentile. FFMD defined as FFMI <10^th percentile.

STATISTICS

T-tests compared NWA, FFMD and clinical measurements. Pearson correlations analyzed fat-free mass index (FFMI), fat mass index (FMI), BMI and clinical measurements.

RESULTS

This study included 114 patients.  Mean age 12 years, 72 female. A high prevalence of FFMD existed (n=66, 38.6%).  FMI and FFMI correlated with FEV1% (r: 0.23, p:0.01, r: 0.36, p<0.001, respectively) and BMD (r: 0.29, p:0.002). FMI and hospital admissions were related (r:-0.23,p:0.01). FFMD was associated with 9.5% lower FEV1% (p=0.001) and lower BMD Z-score by 1.1 (p<0.001) when compared to no FFMD.

CONCLUSION

This cohort of children with CF had a high prevalence of FFMD and low prevalence of NWA.  FFMD was associated with worsened clinical measurements. Patients with FFMD need additional exercise or nutritional intervention. Heterogeneity of body composition definitions creates need for more research.

Secular Changes in Body Build and Body Composition in Czech Preschool Children in the Context of Latent Obesity

Changes in lifestyle can be significantly reflected in growth and development. Adaptations to reduced levels of physical activity, together with non-corresponding nutritional intakes, can result in body build and body composition changes at an early age. The present cross-sectional study aimed to evaluate the secular trend of modifications of body composition and body mass index (BMI) in Czech preschoolers over the last two to three decades. Boys and girls (386 boys and 372 girls) aged 4 to 6 years in 2014–2019 were measured. Outcome data were compared with the reference sample of preschoolers from 1990: 911 boys and 896 girls. Body height, BMI, and percentage of body fat, muscle, and bone mass were evaluated. Height and BMI have not changed. Body fat increased in both genders (p < 0.01), and contrarily, a significant reduction of muscle and skeletal mass was revealed (p < 0.001). Significant changes in body composition and unchanged BMI indicate the development of latent obesity during the last few decades. Due to latent obesity in a recent cohort, the differences in the prevalence of overweight and obesity markers according to BMI and fat percentage were tested. The prevalence of overweight and obesity was higher by 7.2% in boys, and by 6.5% in girls, as compared to children evaluated according to only their BMI results. Secular changes in preschoolers’ physical builds over the last 25 years are not reflected in body height and BMI, but in body composition. Insufficient development of active, lean body mass proportionally compensated by increased fat mass was also indicated.

Impaired Cardiorespiratory Fitness and Muscle Strength in Children with Normal-Weight Obesity

Despite the health-related implications of normal-weight obesity in children, very little research has explored the fundamental associations between this status and important long-term health parameters. Therefore, the aim of the current study was to investigate the physical fitness of children with normal-weight obesity, in comparison to normal-weight non obese and overweight and obese counterparts. A total of 328 middle-school-aged children (9.8 ± 0.5 y) took part in this study (n = 44 normal-weight obese; n = 237; normal-weight non obese; n = 47 overweight and obese). Height, weight, and body-fatness were measured. Four physical fitness tests were conducted: (1) Multistage fitness test; (2) shuttle run 4 × 10 m; (3) sit-ups for 60 s; (4) the broad jump. Welch’s analysis of variance (ANOVA), stratified by sex, with post-hoc testing where necessary, was performed. Children with normal-weight obesity had significantly (p < 0.01) lower cardio-respiratory and muscular fitness than normal-weight non obese peers. In addition, normal-weight obese and overweight and obese boys had comparable deficits in strength and explosiveness of lower limbs, speed coordination, and endurance, compared to normal-weight non obese counterparts. Normal-weight obese children appear to have similar deficits in PF as their overweight and obese peers, compared to normal-weight non obese counterparts, whilst boys had larger deficits than girls.

Cardiometabolic risk and health behaviours in adolescents with normal-weight obesity: a systematic review

OBJECTIVE

To analyse the presence of cardiometabolic risk factors in adolescents with normal-weight obesity (NWO), as well as to investigate health behaviours related to the phenotype.

DESIGN

The study was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines and the bibliographic search was carried out in the PubMed, Scielo and ScienceDirect databases.

SETTING

School, university and population.

PARTICIPANTS

Adolescents between 10 and 19 years old.

RESULTS

A total of eight papers were included. Most studies have found a relationship between NWO and the presence of cardiometabolic risk factors, such as high waist circumference, unfavourable lipid and glycid profile. As for health behaviours, three of the eight studies included evaluated eating habits; however, the results were not conclusive. In addition, four studies analysed the practice of physical activity or physical fitness, which was lower in NWO.

CONCLUSIONS

The available evidence indicates that NWO is related to the early development of cardiometabolic changes, physical inactivity and less physical fitness in adolescents. The results also reveal the importance of early detection of the phenotype, as well as the need for further research on the associated factors to prevent future diseases. Registration (PROSPERO: CRD42020161204).

Sociodemographic and Lifestyle Factors in relation to Overweight Defined by BMI and "Normal-Weight Obesity"

Sociodemographic factors and lifestyle habits affect body weight and body composition. A new syndrome, called normal-weight obesity (NWO), is found in individuals with normal weight and excess body fat in contrast to lean and overweight individuals. The aim of the present study was to explore the associations between sociodemographic factors and smoking and alcohol habits and lower versus higher BMI (≥25 kg/m²) and to examine whether categorization into lean, NWO, and overweight leads to further information about sociodemographic and lifestyle associations, compared with the common categorization defined by BMI. A cohort of 17,724 participants (9,936 females, 56.1%) from the EpiHealth study, with a median age of 61 (53-67) years, was examined. The participants answered a questionnaire about lifestyle, and weight and fat percentage were measured. Associations between sociodemographic factors and lifestyle habits and lower versus higher BMI, and lean versus NWO or lean and NWO versus overweight were calculated by binary logistic regression. Male sex, age, sick leave/disability, married/cohabitating, divorced/widowed, former smoking, and a high alcohol consumption were associated with higher BMI, whereas higher education and frequent alcohol consumption were inversely associated (all p < 0.001). The associations were similar to associations with lean versus overweight and NWO versus overweight, except for age in the latter case. Associations with lean versus NWO differed from those of lower versus higher BMI, with an association with retirement, an inverse association with male sex (OR, 0.664; 95% confidence interval, 0.591-0.746), and no associations with marital status, smoking, and alcohol consumption frequency. Associations with age and occupation were sex dependent, in contrast to other variables examined. Thus, sociodemographic and lifestyle habits showed similar associations with lower versus higher BMI as with lean and NWO versus overweight, whereas lean versus NWO showed different directions of associations regarding sex, marital status, occupation, smoking, and frequency of alcohol consumption.