Body shape indices and cardiometabolic risk in adolescents

Background: “A Body Shape Index” (ABSI) is a recently proposed index that standardizes waist circumference for body mass index (BMI) and height using the scaling exponents 2/3 and 1/2, respectively, estimated from adults. Incidentally, waist-to-height ratio has been suggested as an indicator of cardiometabolic risk in adolescents.

Aims: This study aims to estimate the scaling exponents for standardizing waist circumference for BMI and height in Chinese adolescents and to estimate and compare the ability of various body shape indices in predicting cardiometabolic risk in adolescents.

Subjects and methods: Participants aged 10–17 years in the 2009 China Health and Nutrition Survey were analysed.

Results: The appropriate scaling exponents for standardizing waist circumference for BMI and height in this adolescent sample were 0.45 and 0.55, respectively. A new ABSI-adolescents was defined accordingly. Ignoring the age dependence in the scaling exponents would lead to confounded associations. The ABSI-adolescents and the waist-to-height ratio were more associated with glycated haemoglobin and pre-diabetes, but not blood pressure, than the BMI was.

Conclusion: The scaling exponent for standardizing waist circumference for BMI is age-dependent. Indices based on waist circumference adjusted for BMI are more associated with glycated haemoglobin than BMI in adolescents.     

Indices of central and general obesity and cardiometabolic risk among adolescents in three ethnic groups in north-west China

Abstract

Background: ‘A Body Shape Index-Adolescents’ (ABSI-Adolescents) and waist-to-height ratio are recently proposed indices that quantify central obesity in adolescents.

Aims: To investigate the scaling exponents to standardise waist circumference (WC) for body mass index (BMI) and height and to investigate the association between BMI, WC-based indices and cardiometabolic outcomes in adolescents of three ethnic groups.

Subjects and methods: A cross-sectional study of 1755 adolescents (516 Hans, 565 Uygurs, 674 Kazakhs) was conducted in north-west China. Correlation between indices of obesity and blood pressure (BP) and fasting blood glucose (FBG) were estimated and compared.

Results: Two ethnic groups (Han and Kazakh) had WC-BMI-height profiles different from the previously proposed ABSI-Adolescents and, therefore, required different scaling exponents for WC standardization. After adjustment for age and gender, WC and BMI have similar associations with BP and FBG. After further adjustment for BMI, WC remained significantly associated with FBG in all three ethnic groups (each p?<?0.01) and with BP in Han and Kazakh adolescents (each p?<?0.05).

Conclusion: Body proportionality varied between the ethnic groups. WC and WC-based indices were associated with blood pressure and fasting blood glucose in adolescents of three ethnicities. The WC-based indices did not out-perform WC per se.     

Association between the serum concentrations of 12 cytokines and growth factors and metabolic syndrome in patients undergoing angiography

Abstract

We aimed to compare the concentrations of serum cytokines in patients undergoing coronary angiography and finding their possible associations with metabolic syndrome. Twelve serum cytokines and growth factors (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, MCP-1, IFN-γ, EGF, and VEGF) were measured by sandwich chemiluminescence assays, on the Evidence Investigator^® system. There were significant differences regarding sex, height, weight, BMI, WC, HC, FPG, TG and HDL-C between those with and without MetS in patients undergoing angiography (p?<?.05). Serum concentrations of IL-6 and INF-γ were significantly higher in subjects with MetS, compared to those without MetS (p?=?.031 and p?=?.035, respectively). However, only serum IL-6 was associated with the presence of MetS (β?=?1.215, CI?=?1.047–1.409, p?=?.010). From several serum cytokines and growth factors assessed in patients, IL-6 was the only serum cytokine that was significantly different between those with and without MetS after correction for confounding factors.     

BMI and BMI SDS in childhood: annual increments and conditional change

Background Early detection of abnormal weight gain in childhood may be important for preventive purposes. It is still debated which annual changes in BMI should warrant attention.

Aim To analyse 1-year increments of Body Mass Index (BMI) and standardised BMI (BMI SDS) in childhood and explore conditional change in BMI SDS as an alternative method to evaluate 1-year changes in BMI.

Subjects and methods The distributions of 1-year increments of BMI (kg/m²) and BMI SDS are summarised by percentiles. Differences according to sex, age, height, weight, initial BMI and weight status on the BMI and BMI SDS increments were assessed with multiple linear regression. Conditional change in BMI SDS was based on the correlation between annual BMI measurements converted to SDS.

Results BMI increments depended significantly on sex, height, weight and initial BMI. Changes in BMI SDS depended significantly only on the initial BMI SDS. The distribution of conditional change in BMI SDS using a two-correlation model was close to normal (mean = 0.11, SD = 1.02, n?=?1167), with 3.2% (2.3–4.4%) of the observations below ?2 SD and 2.8% (2.0–4.0%) above +2 SD.

Conclusion Conditional change in BMI SDS can be used to detect unexpected large changes in BMI SDS. Although this method requires the use of a computer, it may be clinically useful to detect aberrant weight development.     

Nutritional status and height,weight and BMI centiles of school-aged children and adolescents of 6–18-years from Kinshasa (DRC)

Background: The last study to establish centiles of main anthropometric measurements in Kinshasa was conducted over 60 years ago, which questions its current adequacy to describe or monitor growth in this population.

Aim: To assess the nutritional status of school-aged children and adolescents and to estimate centile curves of height, weight and body mass index (BMI).

Subjects and methods: A representative sample of 7541 school-aged children and adolescents (48% boys) aged 6–18 years was measured between 2010–2013. Smooth centiles of height, weight and BMI-for-age were estimated with the LMS method and compared with the WHO 2007 reference. Nutritional status was assessed by comparing measurements of height and BMI against the appropriate WHO cut-offs.

Results: Compared to the WHO reference, percentiles of height and BMI were generally lower. This difference was larger in boys than in girls and increased as they approached adolescence. The prevalence of short stature (?1 SD) was higher in girls (8.6%) than in boys (4.5%).

Conclusion: Children from Kinshasa fall below WHO centile references. This study established up-to-date centile curves for height, weight and BMI by age in children and adolescents. These reference curves describe the current status of these anthropometric markers and can be used as a basis for comparison in future studies.     

Association of Anthropometric Measures with Cardiovascular Risk Factors and Metabolic Syndrome in Normal-Weight Children and Adolescents: The CASPIAN III Study

ObjectiveThis nationwide study was conducted to determine the association of anthropometric measures with cardiovascular risk factors and metabolic syndrome (MetS) in Iranian normal-weight children and adolescents.MethodsWe analyzed the data of 3,565 children and adolescents (50.3% boys), aged 10-18 years, with a normal BMI (5th-84th percentile) obtained from the third survey of ‘Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease’ (CASPIAN III) study. The diagnostic criteria for MetS were defined by the International Diabetes Federation consensus.ResultsThe prevalence of MetS for 10- to 13.9-year-old boys, 14- to 18-year-old boys, 10- to 13.9-year-old girls, and 14- to 18-year-old girls were 1.4, 2.8, 2.3, and 3.3%, respectively. After adjustment for age and sex, each unit increase in BMI (within normal range) and waist circumference increased the odds of MetS from 6 to 72% and from 1 to 20%, respectively. The dominant pattern of dyslipidemia among the participants was high triglycerides and low high-density lipoprotein cholesterol.ConclusionThis study complements recent research about the high frequency of metabolic risk factors among normal-weight individuals in the pediatric age group.Key Words: Anthropometric, Cardiovascular, Metabolic syndrome, Children, Adolescents     

Weight-for-length/height growth curves for children and adolescents in China in comparison with body mass index in prevalence estimates of malnutrition

Background: It is important to update weight-for-length/height growth curves in China and re-examine their performance in screening malnutrition.

Aim: To develop weight-for-length/height growth curves for Chinese children and adolescents.

Subjects and methods: A total of 94 302 children aged 0–19 years with complete sex, age, weight and length/height data were obtained from two cross-sectional large-scaled national surveys in China. Weight-for-length/height growth curves were constructed using the LMS method before and after average spermarcheal/menarcheal ages, respectively. Screening performance in prevalence estimates of wasting, overweight and obesity was compared between weight-for-height and body mass index (BMI) criteria based on a test population of 21?416 children aged 3–18.

Results: The smoothed weight-for-length percentiles and Z-scores growth curves with length 46–110?cm for both sexes and weight-for-height with height 70–180?cm for boys and 70–170?cm for girls were established. The weight-for-height and BMI-for-age had strong correlation in screening wasting, overweight and obesity in each age–sex group. There was no striking difference in prevalence estimates of wasting, overweight and obesity between two indicators except for obesity prevalence at ages 6–11.

Conclusion: This set of smoothed weight-for-length/height growth curves may be useful in assessing nutritional status from infants to post-pubertal adolescents.     

Sex Difference in the Associations among Obesity-Related Indices with Metabolic Syndrome in Patients with Type 2 Diabetes Mellitus

Background: The aim of this study was to investigate the associations among obesity-related indices and MetS in diabetic patients, and explore sex differences in these associations.Methods: Patients with type 2 DM were included from two hospitals in southern Taiwan. The Adult Treatment Panel III criteria for an Asian population were used to define MetS. In addition, the following obesity-related indices were evaluated: waist-to-height ratio, waist-hip ratio (WHR), conicity index (CI), body mass index (BMI), body roundness index, body adiposity index, lipid accumulation product (LAP), abdominal volume index, visceral adiposity index (VAI), abdominal volume index and triglyceride-glucose index.Results: A total of 1,872 patients with type 2 DM (mean age 64.0 ± 11.3 years, 808 males and 1,064 females) were enrolled. The prevalence rates of MetS were 59.8% and 76.4% in the males and female (p < 0.001), respectively. All of the obesity-related indices were associated with MetS in both sex (all p < 0.001). LAP and BMI had the greatest areas under the receiver operating characteristic curves in both sex. In addition, the interactions between BMI and sex (p = 0.036), WHR and sex (p = 0.016), and CI and sex (p = 0.026) on MetS were statistically significant.Conclusions: In conclusion, this study demonstrated significant relationships between obesity-related indices and MetS among patients with type 2 DM. LAP and VAI were powerful predictors in both sex. The associations of BMI, WHR and CI on MetS were more significant in the men than in the women.     

Associations between body shape,body adiposity and other indices: a case study of hypertension in Chinese children and adolescents

Abstract

Background: A Body Shape Index (ABSI) and the Body Adiposity Index (BAI) are used to quantify body shape for adults. However, only a few studies have been conducted confirming whether ABSI or BAI is a better index for predicating hypertension and pre-hypertension in Chinese children and adolescents.

Aim: To estimate scaling exponents for using ABSI with Chinese children and adolescents, comparing body shape indices used for predicting hypertension and pre-hypertension and determine which obesity indices can serve as predictors.

Subjects and methods: Data from children and adolescents aged 7–17?years in the 2011 Chinese Health and Nutrition Survey were analysed. Partial correlation analysis and receiver operating characteristics analysis were applied.

Results: The area under curve (AUC) values for all the predictors are better for differentiating hypertension than pre-hypertension. Body Mass Index (BMI) gave the largest AUC in both children and adolescents. ABSI and ABSI-(C) (ABSI for Chinese children and adolescents) were unable to differentiate hypertension or pre-hypertension in the population. BAI could only differentiate pre-hypertension in girls aged 7–12?years (AUC = 0.353, p?<?0.05).

Conclusion: ABSI, ABSI-(C) and BAI are not more associated with hypertension or pre-hypertension than BMI, waist circumference and waist-to-height ratio in Chinese children and adolescents.     

Insight into the longitudinal relationship between chronic subclinical inflammation and obesity from adolescence to early adulthood: a dual trajectory analysis

Objectives and design

This study aimed to understand the longitudinal relationship between C-reactive protein (CRP) and body mass index (BMI) from adolescence to early adulthood.

Methods

CRP and BMI were collected from participants of the Raine Study Gen2 at 14-, 17-, 20- and 22-year follow-ups (n?=?1312). A dual trajectory analysis was conducted to assess the association between CRP and BMI trajectories, providing conditional probabilities of membership of CRP trajectory membership given BMI trajectory membership. Best model fit was assessed by systematically fitting two to eight trajectory groups with linear and quadratic terms and comparing models according to the Bayesian Information Criterion statistic.

Results

The three CRP trajectories were; “stable-low” (71.0%), “low-to-high” (13.8%) and “stable-high” (15.2%). Participants in a “high-increasing” BMI trajectory had a higher probability of being in the “stable-high” CRP trajectory (60.4% of participants). In contrast, individuals in the “medium-increasing” BMI trajectory did not have a significantly increased probability of being in the “stable-high” CRP trajectory.

Conclusions

These findings support that chronic sub-clinical inflammation is present through adolescence into early adulthood in some individuals. Targeting chronic sub-clinical inflammation though obesity prevention strategies may be important for improving future health outcomes.

     

National reference centiles of anthropometric indices and BMI cut-off values in a child population in Nepal

Background: There is a need for national- or ethnicity-specific growth reference values in developing countries like Nepal, where rapid urbanisation and consequential nutritional transition is taking place.

Aim: To establish national growth reference percentiles for anthropometric indices and to propose body mass index (BMI) cut-off values for Nepalese schoolchildren.

Methods: This study comprised 1135 Nepalese schoolchildren of four World Health Organization (WHO) indexed age groups (5-, 6-, 12- and 15-year-olds). The age- and gender-specific smoothed percentile curves for anthropometric indices (height, weight, BMI, waist circumference, waist-to-hip-ratio and waist-to-height-ratio) were constructed using LMS method and the corresponding Z-scores were computed. The Receiver Operating Characteristic analysis was used to determine BMI cut-off values based on the International Obesity Taskforce (IOTF) and the WHO growth references.

Results: The age- and gender-specified smoothed percentile values of anthropometric indices at 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentiles were computed. The BMI cut-off values for thinness (?1.2 SDS/12th percentile), overweight (+1.2 SDS/88th percentile) and obesity (+2.1 SDS/98th percentile) had high discriminating power, and high sensitivity and specificity.

Conclusion: The Nepali anthropometric cut-off values proposed here can be recommended to be applied into research, and to identify public health risks in Nepal among these age groups.     

Associations of the infancy body mass index peak with anthropometry and cardiometabolic risk in Mexican adolescents

Background: Early-life growth dynamics are associated with future health. Little is known regarding timing and magnitude of the infancy body mass index (BMI) peak with adiposity and metabolic biomarkers during adolescence.

Aim: To examine associations of the infancy BMI peak with anthropometry and cardiometabolic risk during peripuberty.

Methods: Among 163 ELEMENT participants, this study estimated age and magnitude of the infancy BMI peak from eight anthropometric measurements from birth–36?months using Newton’s Growth Models, an acceleration-based process model. Associations were examined of the infancy milestones with anthropometry and cardiometabolic risk at 8–14?years using linear regression models that accounted for maternal calcium supplementation and age; child’s birthweight, sex, and age; and the other infancy milestone.

Results: Median age at the infancy BMI peak was 9.6?months, and median peak BMI was 16.5?kg/m². Later age and larger magnitude of the peak predicted higher BMI z-score, waist circumference, and skinfold thicknesses; i.e. each 1?month of age at peak and each 1?kg/m² of peak BMI corresponded with 0.04 (0.01–0.07) and 0.33 (0.17–0.48) units of higher BMI z-score, respectively. Later age at peak was also a determinant of worse glycaemia and higher blood pressure.

Conclusion: Later age and larger magnitude of the infancy BMI peak are associated with higher adiposity at 8–14?years of age. Later age but not magnitude of the BMI peak are related to a worse cardiometabolic profile during peripuberty.     

José Jordan

Background: A child's adult height is commonly predicted using their target height, based on mid-parent height. However, if no growth disorder is suspected, the child's current height is a far better predictor of their adult height.

Aim: To develop a chart to predict a child's adult height from their current height, adjusting for regression to the mean.

Subjects and methods: Data from the First Zurich Longitudinal Growth Study provided correlations between child height and adult height by age and sex, for use in a regression model predicting adult height centile from child height centile. The model was validated using data from the British 1946 and 1958 birth cohorts.

Results: The chart is illustrated superimposed on the British 1990 boys height chart. The predicted height has a standard error of 4–5 cm for ages from 4 years to puberty in both sexes. The regression adjustment partially compensates for biased predictions in early and late developers in puberty. A simplified version of the chart for restricted age ranges is also shown, as used on the UK-WHO 0–4 years growth charts.

Conclusion: The height prediction chart should be of value for parents, and indirectly professionals, to predict adult height in their children.     

Predictors of Weight Loss in Obese Older Adults: Findings from the USA and the UK

ObjectiveTo examine the prevalence and demographic predictors of clinically meaningful weight loss in community samples of obese older adults in the USA and the UK.MethodsData were from obese older adults (BMI ≥ 30 kg/m²; age ≥ 52 years), free of a cancer diagnosis, from the Health and Retirement Study (HRS; n = 3398) and the English Longitudinal Study of Ageing (ELSA; n = 998). Weight change was assessed from 2004 to 2008. Multivariable logistic regression tested whether age, sex, ethnicity, marital status, education, or BMI predicted ≥ 5% weight loss.ResultsOver a quarter (28.7%) of obese participants from HRS and 16.6% from ELSA lost ≥ 5% weight. Being female (odds ratio (OR) = 1.31, 95% confidence interval (CI) = 1.11-1.54) and heavier (BMI ≥ 35 kg/m²) (OR = 1.60, 95% CI = 1.37-1.87) predicted weight loss in HRS. Trends were similar in ELSA (female: OR = 1.18, 95% CI = 0.83-1.69; BMI ≥ 35 kg/m²: OR = 1.24, 95% CI = 0.85-1.82). ORs were increased in ≥ 65-year-olds in HRS (OR = 1.55, 95% CI = 1.33-1.81), and reduced in married people in ELSA (OR = 0.69, 95% CI = 0.48-1.00). Neither education nor ethnicity predicted weight loss in either cohort.ConclusionA high proportion of obese older adults experience clinically meaningful weight loss, but few demographic variables consistently predict weight loss in this population.Key Words: Weight loss, Aging, Obesity, Prevalence, Predictors     

At what age do normal weight Canadian children become overweight adults? Differences according to sex and metric

Background: The prevalence of overweight and obesity doubles between adolescence and young adulthood; however, the exact age, and appropriate metric to use to identify when overweight develops is still debated.

Aim: To examine the age of onset of overweight by sex and four metrics: body mass index (BMI), fat mass (%FM), waist circumference (WC) and waist-to-height ratio (WHtR).

Subjects and methods: Between 1991 and 2017, serial measures of body composition were taken on 237 (108 males) individuals (aged 8–40?years of age). Hierarchical random effects models were used to develop growth curves. Curves were compared to BMI, %FM and WC overweight age- and sex-specific cut-points.

Results: In males, the BMI growth curve crossed the cut-point at 22.0?years, compared to 23.5 and 26.5?years for WHtR and %FM, respectively; WC cut-off was not reached until 36?years. In females, the BMI growth curve crossed the overweight cut-point at 21.5?years, compared to 14.2?years for %FM and 21.9 and 27.5?years for WC and WHtR, respectively.

Conclusion: In summary, overweight onset occurs during young adulthood with the exception of WC in males. BMI in males and %FM in females were the metrics identifying overweight the earliest.     

Influence of age,sex and somatic variables on the motor performance of pre-school children

Abstract

Background: Biological factors can affect the motor development process of children. However, the magnitude of these effects throughout the developmental process remains fairly unknown.

Aim: To determine the influence of age, sex and selected somatic measures on the motor performance of pre-school children.

Subjects and methods: Three hundred and sixty-seven pre-schoolers (172 boys and 195 girls), aged from 3–5 years old, were recruited from 10 public pre-schools located in the district of Viana do Castelo, Portugal. The children’s motor performance was assessed by five motor sub-tests of Peabody Developmental Motor Scales-2: grasping, visuo-motor integration, stationary, locomotion and object manipulation sub-tests. Age, sex, height, weight and BMI were considered as hypothetical predictors of motor performance. Pearson’s correlation test and multiple linear regression analysis were used to explore the magnitude of the relationship between motor sub-tests and the hypothetical predictors.

Results: Depending on the motor sub-test and age group, the models predicted motor performance from a minimum of 3.6% to a maximum of 34.4%. Age in months and sex stood out as the main predictors of motor performance.

Conclusions: The relationship between motor performance and selected biological factors varied with age and with the specificity of the motor test.     

Independent associations of body-size adjusted fat mass and fat-free mass with the metabolic syndrome in Chinese

Background: Excess fat leads to adverse health outcomes. Most previous studies investigating body fatness using BMI or fat percentage, which contain both fat mass and fat-free mass, were not able to differentiate the exposure.

Aim: The present study assessed the independent association of fat and fat-free mass with metabolic syndrome (MetS) in Chinese.

Subjects and methods: A population-based study of 1144 subjects aged 50–70 from urban and rural areas of Shanghai in 2005–2006 was employed. Body composition was measured with DEXA. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated. MetS was defined using the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria without waist circumference for its high correlation with body composition.

Results: Both FMI and FFMI were significantly related with higher odds of MetS (OR 3.97, 95% CI 2.58–6.09 for FMI; OR 2.67, 95% CI 1.70–4.18 for FFMI, the highest quartile vs the lowest group) after adjusting for age, residence, sex, smoking, drinking, physical activity, medication, family history of chronic diseases, and fat-free mass (for FMI) or fat mass (for FFMI).

Conclusion: Both FMI and FFMI are independently associated with increased MetS risks. Proper expression of body composition is essential in assessing body composition and disease risk association.     

Aging and HIV Infection: A Comparison Between Older HIV-Infected Persons and the General Population

Abstract

Background: As HIV-infected persons age, the relative contribution of HIV infection, combination antiretroviral therapy (cART), and the normal aging process to the frequent comorbidities is unknown.Methods: We prospectively evaluated comorbidities, cardiovascular risk, cognitive function, and anthropomorphic and laboratory parameters of HIV-infected persons aged 50 years and over in two US urban clinics. Results were compared to controls from the National Health and Nutrition Examination Survey (NHANES) matched 1:1 by age, race, gender, smoking status, and body mass index (BMI).Results: We enrolled 122 HIV-infected persons; median age 55 years, 83% male, 57% Caucasian, 39% current smokers, mean BMI 26 kg/m², and 92% on cART. Compared to controls, HIV-infected persons had a higher prevalence of hypertension (54% vs 38%), hypertriglyceridemia (51% vs 33%), low bone mineral density (BMD) (39% vs 0%), and lipodystrophy and greater receipt of antihypertensive and lipid-lowering medications (all Ps < .05). Groups were similar in prevalence of coronary heart disease, diabetes mellitus, chronic viral hepatitis, non-AIDS-defining malignancies and Framingham Risk and cognitive function scores.Conclusions: Older HIV-infected persons have a higher prevalence of hypertension, hypertriglyceridemia, low BMD, and lipodystrophy than matched controls, suggesting that HIV and treatment-related factors exceed “normal” aging in the development of those problems.     

Blood pressure and sexual maturity in adolescents: The Heartfelt Study

This study investigates sexual maturity as a predictor of resting blood pressures independent of other known predictors, in 179 boys and 204 girls 11‐16 years of age from the Heartfelt Study. The sample included youth of African (n = 140), Mexican (n = 117), and European and “other” (n = 126) backgrounds. Sexual maturity was assessed during clinical examination of three standard indicators for each sex. Systolic and diastolic blood pressures were higher in children of maturity stages IV and V, compared to stages I–III, in each gender/ethnic group (P < 0.01 in almost all groups). Boys and girls advanced in sexual maturity for their age group, had significantly higher systolic blood pressures (but not diastolic) than the less advanced in linear models that included height, body mass index (BMI), ethnicity, and age as co‐predictors. Diastolic blood pressures were predicted by height in boys and by age and the BMI in girls. This analysis, using a very conservative approach, suggests that sexual maturity provides important and independent information on systolic blood pressure in adolescents. Further investigation of its role in 24‐hr blood pressures and in blood pressures taken during physical and emotional stress, is recommended. Am. J. Hum. Biol. 13:227–234, 2001. © 2001 Wiley‐Liss, Inc.