Reference data for body composition parameters in normal-weight Polish adolescents: results from the population-based ADOPOLNOR study.

The aim of this study was to develop age- and sex-specific reference data for body composition parameters, including fat-free mass (FFM), body cell mass (BCM), fat mass (FM) and related indices, fat mass percentage (FM%), total body water (TBW) and muscle mass (MM) and to assess differences in these parameters between male and female adolescents. Bioelectrical impedance analysis (BIA) data were obtained from an ethnically homogeneous sub-sample of 4037 normal-weight participants selected on the basis of BMI from the total sample (2005 males and 2032 females aged 10-18 years) of the ADOPOLNOR study, a cross-sectional population-based survey conducted in western Poland. The LMS method and RefCurv version 0.4.2 software package were used to calculate centile values and plot smoothed centile curves. The results showed age-related changes in body composition parameters and a clear sexual dimorphism. From the age of 13 (for FFM) or 14 (for BCM, BCMI and MM) or throughout adolescence (for TBW and FFMI), boys had consistently higher values for these parameters than girls (p < 0.01 for each). However, they had significantly lower values for FM, FMI and FM% (1.3, 1.6 and 1.5 times lower at 18 years, respectively), indicating a lower proportion of body fat than girls (p < 0.01 for each). The centile values and curves were specific for boys and girls of all ages. Compared with other European adolescent cohorts, the data fit the normal-weight subsamples better than the population reference data. CONCLUSION: This study provides reference data for body composition in normal (healthy) weight Polish adolescents, providing a contextualised framework that takes into account the unique physiological and environmental factors of the region. These reference data may also be useful for other Central European adolescents. WHAT IS KNOWN: • Adolescence is a period of significant physical growth and increased susceptibility to nutritional problems due to factors such as suboptimal nutrition, unhealthy dietary choices, inadequate physical activity and psychosocial stressors related to body image concerns. • Body composition (BC) parameters, rather than BMI alone, are more effective in identifying nutritional abnormalities and health risks such as eating disorders, obesity and chronic diseases. Existing studies provide reference data for BC parameters, but often do not cover all relevant measures or specific regional populations. WHAT IS NEW: • This study provides new age- and sex-specific reference values for a comprehensive range of body composition parameters, including body cell mass (BCM), total body water (TBW) and muscle mass (MM), in addition to fat-free mass (FFM) and fat mass (FM), in a large, ethnically homogeneous, normal-weight population of Polish adolescents aged 10-18 years. • These reference values for the normalweight cohort reflect healthy adolescent growth and body composition patterns, minimising bias from abnormal weight status. In addition, they can be applied to other Central European adolescent populations.

Canadian adult reference data for body composition, trabecular bone score and advanced hip analysis using DXA.

DXA-derived reference data for visceral adipose tissue (VAT) and advanced hip analysis (AHA) parameters spanning the entire adult lifespan are limited. The purpose of this study was to develop age-, site- and sex-specific reference data for dual X-ray absorptiometry (DXA) -derived body composition, trabecular bone score (TBS) and advanced hip analysis (AHA) parameters across the adult lifespan. Adults (N = 908; female: 561 and male: 347) from Calgary and the surrounding area over the age of 20 years participated in this study. Participants received DXA scans of their hip (total hip [TH] and femoral neck [FN]), lumbar spine [LS], forearm [33 % site] and total body (iDXA, GE Lunar, GE Healthcare). Areal bone mineral density (aBMD, g/cm2) was captured at all sites, and body composition variables, including lean mass, fat mass and percent fat, were analyzed from the total body scan. VAT mass was assessed from total body DXA scans. Advanced hip analysis (AHA) was performed on hip scans and trabecular bone score (TBS) on the LS scans to assess bone quality. Site- and sex-specific centile curves and tables were generated using the Generalized Additive Models for Location, Scale, and Shape (GAMLSS) method. Clinicians and researchers can use these Canadian reference data as a tool to assess body composition, TBS and AHA parameters across the adult lifespan.

Reference data and calculators for second-generation HR-pQCT measures of the radius and tibia at anatomically standardized regions in White adults.

High-resolution peripheral quantitative computed tomography (HR-pQCT) is a powerful tool to assess bone health. To determine how an individual's or population of interest's HR-pQCT outcomes compare to expected, reference data are required. This study provides reference data for HR-pQCT measures acquired in a population of White adults. PURPOSE: To provide age- and sex-specific reference data for high-resolution peripheral quantitative computed tomography (HR-pQCT) measures of the distal and diaphyseal radius and tibia acquired using a second-generation scanner and percent-of-length offsets proximal from the end of the bone. METHODS: Data were acquired in White adults (aged 18-80 years) living in the Midwest region of the USA. HR-pQCT scans were performed at the 4% distal radius, 30% diaphyseal radius, 7.3% distal tibia, and 30% diaphyseal tibia. Centile curves were fit to the data using the LMS approach. RESULTS: Scans of 867 females and 317 males were included. The fitted centile curves reveal HR-pQCT differences between ages, sexes, and sites. They also indicate differences when compared to data obtained by others using fixed length offsets. Excel-based calculators based on the current data were developed and are provided to enable computation of subject-specific percentiles, z-scores, and t-scores and to plot an individual's outcomes on the fitted curves. In addition, regression equations are provided to convert estimated failure load acquired with the conventional criteria utilized with first-generation scanners and those specifically developed for second-generation scanners. CONCLUSION: The current study provides unique data and resources. The combination of the reference data and calculators provide clinicians and investigators an ability to assess HR-pQCT outcomes in an individual or population of interest, when using the described scanning and analysis procedure. Ultimately, the expectation is these data will be expanded over time so the wealth of information HR-pQCT provides becomes increasingly interpretable and utilized.

Development of muscle mass and body fat reference curves for white male UK firefighters.

OBJECTIVE: This study describes the development of the world's first suite of firefighter body composition centile reference curves which can be used as both academic research tools and clinical references, to plot and track individual firefighter skeletal muscle mass (SMM) and fat mass (FM) measurements against the representative reference sample. METHODS: The body composition of 497 white male London (England) firefighters was measured by anthropometry and bioelectrical impedance analysis. Smoothed centile curves were then generated for skeletal muscle mass index (SMMI), fat mass index (FMI), body fat percentage (BF%) and waist-to-height ratio (WHtR). RESULTS: Between 48 and 62 years, firefighter SMMI is greater than the UK white male age-matched general population by a mean of 0.35 units, although SMMI declines 0.006 units/years faster in firefighters between these ages. This is estimated to translate to a mean decline of approximately 0.6% of absolute SMM per year. Between 40 and 49 years, firefighter FMI is 0.1 units greater than the UK white male age-matched general population, which becomes identical (7 units) between 50 and 54 years. At the 50th centile, WHtR exceeds 0.5 by 39 years reaching 0.55 at 62 years. This contrasts with FMI which remains stable from 47 years. CONCLUSION: Firefighters in this study possess greater FM and SMM compared with the UK general population. SMM appears to decline rapidly within older age ranges. These references offer a novel improvement upon the limitations of BMI and BF% for the benefit of an occupational group at elevated risk of cardiovascular disease.

Anthropometric measurements of school-going-girls of the Punjab, Pakistan.

BACKGROUND: Child's growth has been considered an important indicator to evaluate health trends in a population and to devise strategies accordingly. The purpose of the present study was to determine most commonly occurring weight abnormalities among school-going girls from Punjab and to compare with international growth references devised by World Health Organization (WHO) and Centre for Disease Control and Prevention (CDC). METHODS: In this cross-sectional study a sample of 10,050 child and adolescent girls from 12 districts, 35 public/private sector schools, located in rural, semi-urban and urban areas of northern, central and southern Punjab were included. Parameters were measured according to standardised techniques and centile curves obtained by Lambda, Mu, Sigma (LMS) method. RESULTS: The results showed an increase in weight, height and BMI of the Punjabi girls until 15 years. When compared with international growth references, weight and BMI in our population were significantly lowered; however, height was lower during 12-16 years of age and the differences observed were more pronounced with CDC as compared to WHO. When 3rd, 50th and 90th percentiles of weight, height and BMI in our population were compared with international standards, the values were lower in our paediatric population. CONCLUSION: The Punjabi schoolgirls significantly differed from CDC and WHO references, and this difference should be taken into consideration for evaluation of growth abnormalities in our paediatric population. However, in the absence of national reference data, WHO standards have been considered more appropriate for comparison.

Reference Centiles to Monitor the 6-minute-walk Test in Ambulant Children with Cerebral Palsy and Identification of Effects after Rehabilitation Utilizing Whole-body Vibration.

Background: Children with cerebral palsy present age-driven development in gross motor skills and walking capacity. Aims: To precisely monitor the 6-minute walk test (6MWT) in children with CP, GMFCS levels 1 and 2 over 6 months and to assess the effect of a 6-month rehabilitation program including whole-body vibration. Methods: Retrospective analysis of data of 157 children with CP who received standardized rehabilitation (DRKS00011331). 6MWT was assessed at the start (M0) and end of the training (M6), as well as at a 6-month follow-up (M12). Centiles were created using the lambda-mu-sigma (LMS) method. Results: We created 6MWT percentiles using data of all 157 children (M0 data). A medium treatment effect size (Cohen's d = 0.69) was found (M6 and M12 data). Conclusions: The generated centiles may help monitor 6MWT changes over 6 months. Combining WBV and conventional physiotherapy can significantly improve 6MWT in children with CP. Abbreviations: 6MWT: 6-Minute Walk Test; CP: Cerebral palsy; ES: effect size; GMFCS: Gross Motor Function Classification System; GMFM-66: Gross Motor Function Measure 66; LOESS: locally weighted scatterplot smoothing; LMS: lambda-mu-sigma; MCID: minimal clinical important difference; SD: standard deviation; SRM: standardized response mean; WBV: whole-body vibration.

Age-, Site-, and Sex-Specific Normative Centile Curves for HR-pQCT-Derived Microarchitectural and Bone Strength Parameters in a Chinese Mainland Population.

High-resolution peripheral quantitative computed tomography (HR-pQCT) is an advanced 3D imaging technology that has the potential to contribute to fracture risk assessment and early diagnosis of osteoporosis. However, to date no studies have sought to establish normative reference ranges for HR-pQCT measures among individuals from the Chinese mainland, significantly restricting its use. In this study, we collected HR-pQCT scans from 863 healthy Chinese men and women aged 20 to 80 years using the latest-generation scanner (Scanco XtremeCT II, Scanco Medical AG, Brüttisellen, Switzerland). Parameters including volumetric bone mineral density, bone geometry, bone microarchitecture, and bone strength were evaluated. Age-, site-, and sex-specific centile curves were established using generalized additive models for location, scale, and shape with age as the only explanatory variable. Based on established models, age-related variations for different parameters were also quantified. For clinical purposes, the expected values of HR-pQCT parameters for a defined age and a defined percentile or Z-score were provided. We found that the majority of trabecular and bone strength parameters reached their peak at 20 years of age, regardless of sex and site, then declined steadily thereafter. However, most of the cortical bone loss was observed after the age of 50 years. Among the measures, cortical porosity changed most dramatically, and overall, changes were more notable at the radius than the tibia and among women compared with men. Establishing such normative HR-pQCT reference data will provide an important basis for clinical and research applications in mainland China aimed at elucidating microstructural bone damage driven by different disease states or nutritional status. © 2020 American Society for Bone and Mineral Research.

Normative Standards for HRpQCT Parameters in Chinese Men and Women.

Assessing bone architecture using high-resolution peripheral quantitative computed tomography (HRpQCT) has the potential to improve fracture risk assessment. The Normal Reference Study aimed to establish sex-specific reference centile curves for HRpQCT parameters. This was an age-stratified cross-sectional study and 1072 ambulatory Chinese men (n = 544) and women (n = 528) aged 20 to 79 years, who were free from conditions and medications that could affect bone metabolism and had no history of fragility fracture. They were recruited from local communities of Hong Kong. Reference centile curves for each HRpQCT parameter were constructed using generalized additive models for location, scale, and shape with age as the only explanatory variable. Patterns of reference centile curves reflected age-related changes of bone density, microarchitecture, and estimated bone strength. In both sexes, loss of cortical bone was only evident in mid-adulthood, particularly in women with a more rapid fashion probably concurrent with the onset of menopause. In contrast, loss of trabecular bone was subtle or gradual or occurred at an earlier age. Expected values of HRpQCT parameters for a defined sex and age and a defined percentile or Z-score were obtained from these curves. T-scores were calculated using the population with the peak values as the reference and reflected age- or menopause-related bone loss in an older individual or the room to reach the peak potential in a younger individual. These reference centile curves produced a standard describing a norm or desirable target that enables value clinical judgements. Percentiles, Z-scores, and T-scores would be helpful in detecting abnormalities in bone density and microarchitecture arising from various conditions and establishing entry criteria for clinical trials. They also hold the potential to refine the diagnosis of osteoporosis and assessment of fracture risk. © 2018 American Society for Bone and Mineral Research.

Reference charts for height and weight of school children from west malaysia in comparison with the United States centers for disease control and prevention.

BACKGROUND: Reference charts are widely used in healthcare as a screening tool. This study aimed to produce reference growth charts for school children from West Malaysia in comparison with the United States Centers for Disease Control and Prevention (CDC) chart. METHODS: A total of 14,360 school children ranging from 7 to 17 years old from six states in West Malaysia were collected. A two-stage stratified random sampling technique was used to recruit the subjects. Curves were adjusted using Cole's LMS method. The LOWESS method was used to smooth the data. RESULTS: The means and standard deviations for height and weight for both genders are presented. The results showed good agreement with growth patterns in other countries, i.e., males tend to be taller and heavier than females for most age groups. Height and weight of females reached a plateau at 17 years of age; however, males were still growing at this age. The growth charts for West Malaysian school children were compared with the CDC 2000 growth charts for school children in the United States. CONCLUSION: The height and weight for males and females at the start of school-going ages were almost similar. The comparison between the growth charts from this study and the CDC 2000 growth charts indicated that the growth patterns of West Malaysian school children have improved, although the height and weight of American school children were higher than those for West Malaysian school children.