Child growth and armed conflict.

BACKGROUND: During armed conflict, the non-combative population, and particularly children, are susceptible to the effects of conflict from a variety of perspectives; psychological stress, loss of food and resources, loss of accommodation, occupation, income, death of family members, etc. The Lancet recently published a special issue entitled 'Maternal and child health and armed conflict' concluding that the ways in which health can be affected by conflict are protean but systematic evidence is sparse, whatever evidence exists is localised and of low to moderate quality, and that data on adolescents are sparse to non-existent. Whilst this may be true of the challenging environments of conflicts in developing countries, historically recent conflicts in Europe provide an alternative viewpoint that is frequently aired in the Auxological literature but is virtually unknown and/or unrecognised in health settings. METHODS: The current paper summarises three previously published studies based on repeated cross-sectional child growth surveys in London, Oslo, and Stuttgart covering the years of the Second World War. Taken together these studies provide extensive evidence of the response of children to armed conflict in the context of secular tends in growth of children living in industrialised nations during the twentieth century. CONCLUSIONS: The conclusions to all three studies may be summarised, with regard to children in industrialised nations, as: (1) armed conflict adversely affects human growth and health, (2) armed conflict affects all age groups but adolescents more so, (3) all age groups recover from poor growth as conditions improve in relation to post-war health and welfare programmes, (4) pre-war differences in size between SES groups diminish during post-war recovery when accompanied by nutritional, welfare and reconstruction programmes.

Testing the Institute of Medicine (IOM) recommendations on maternal reproductive health and associated neonatal characteristics in a transitional, Mediterranean population.

BACKGROUND: High pre-pregnancy body mass index (BMI) and excessive gestational weight gain (GWG) are significant risk factors for maternal and neonatal health. AIM: To assess pre-pregnancy BMI and GWG during pregnancy and their association with different maternal and neonatal characteristics in the transitional Mediterranean population from the Eastern Adriatic islands. SUBJECTS AND METHODS: Two hundred and sixty-two mother-child dyads from the CRoatian Islands' Birth Cohort Study (CRIBS) were included in the study. Chi-square test, ANOVA, and regression analysis were used to test the association between selected characteristics. RESULTS: In total, 22% of women entered pregnancy as overweight/obese and 46.6% had excessive GWG. Pre-pregnancy overweight and obesity were significantly associated with elevated triglycerides uric acid levels, and decreased HDL cholesterol in pregnancy. Excessive GWG was associated with elevated fibrinogen and lipoprotein A levels. Women with high pre-pregnancy BMI and GWG values were more likely to give birth to babies that were large for gestational age (LGA), additionally confirmed in the multiple logistic regression model. CONCLUSION: High maternal pre-pregnancy BMI and excessive GWG were both significantly associated with deviated biochemical parameters and neonatal size. More careful monitoring of maternal nutritional status can lead to better pre- and perinatal maternal healthcare.

Stress, locus of control, hope and depression as determinants of quality of life of pregnant women: Croatian Islands' Birth Cohort Study (CRIBS).

The aims were to investigate determinants of the quality of life (QoL) of pregnant women. Total of 302 healthy women 18 to 28 weeks of gestation participated in prospective study. WHOQOL-bref, Multidimensional Health Locus of Control scales, Edinburgh Postnatal Depression Scale, and the perceived stress appraisals were administered. Various patterns of predictors for four domains of QoL were identified, for psychological (42% variance explained), social relationship (29%), environmental (29%) and physical health (25%). Depression and hope, together with the extent to which one's health is influenced by powerful other or chance should be targeted in health promotion strategies during pregnancy.

Utilizing auxology to understand ontogeny of extinct hominins: A case study on Homo naledi.

The methods used to study human growth and development (auxology) have not previously been applied within the setting of hominin maturation (ontogeny). Ontogeny is defined here as the pattern of biological change into an adult form, both at the individual and species level. The hominin fossil record has a lack of recovered immature materials, due to such factors as taphonomic processes that destroy pre-adults; the fragility of immature compared to adult bone; and the lower mortality rates of juveniles compared to adults. The recent discovery of pre-adult hominin skeletal material from a single, homogeneous Homo naledi species from the Rising Star cave system in South Africa provides the opportunity for a broader application of auxology methods and thus the need to understand their use in a modern context. Human auxology studies benefit from a robust database, across multiple populations, and with longitudinal studies in order to assess the patterns and variations in typical growth, development and life history stages. Here, we review the approach, vocabulary, and methods of these human studies, investigate commonalities in data with the fossil record, and then advance the reconstruction of ontogeny for the extinct hominin species H. naledi. To this end, we apply an auxology model into the paleontological context to broadly predict H. naledi birthweight of the offspring at 2.06 kg with a range (±1 SD) of 1.89 to 2.24 kg, with a length at birth 45.5 cm. We estimate a H. naledi juvenile partial skeleton DH7 to be a height of 111-125 cm at death.

The growth and development of cohort studies.

Cohort studies are special forms of longitudinal studies that have long been accepted as the primary designs to acquire information on the interaction between the environment and health and the subsequent aetiology and progression of disease. Richard Doll, Regius Professor of Medicine at Oxford University from 1969-1979, was the 20th century's pre-eminent epidemiologist in the UK. He used cohort studies to establish the relationship between smoking and health (primarily cancer) in the 1960s at a time when over 80% of British males smoked. However, the development of cohorts as a means of studying health and wellbeing across the lifespan is rooted in research on tuberculosis in Europe and America in the 1920s and 1930s. Cohort studies were recognised as the primary research design for the study of human growth and development between and during the wars in the USA. Their natural legacy as longitudinal studies emerged in Europe after WWII through a series of growth studies coordinated by the Centre Internationale de L'Enfance in Paris from the 1960s onwards. The failure of two nationally representative birth cohort studies in the USA and UK between 2010 and 2015 has highlighted the previous success of smaller birth cohorts and the advantages gained from standardised methods of measurement and assessment that allow amalgamation and metanalysis of different datasets.

Differences in the relationship of weight to height, and thus the meaning of BMI, according to age, sex, and birth year cohort.

Background: Weight can be adjusted for height using the Benn parameter (kg/mB), where B is the power that minimises the correlation with height.Aim: To investigate how the Benn parameter changes across age (10-65 years) and time (1956-2015) and differs between sexes.Subjects and methods: The sample comprised 49,717 individuals born in 1946, 1958, 1970 or 2001. Cross-sectional estimates of the Benn parameter were produced and cohort differences at ages 10/11 and 42/43 years were examined using linear regression. Multilevel modelling was used to develop trajectories showing how the Benn parameter changed over age from childhood to mid-adulthood in the three older cohorts.Results: The Benn parameter was closest to 2 in childhood but consistently lower across adulthood, particularly in females and the most recent cohort. At ages 10/11 years, the Benn parameter was greater than 3 in both sexes in the 2001 cohort but between 2.2 and 2.7 in the three older cohorts. This difference was estimated to be +0.67 (0.53, 0.81) in males and +0.53 (0.38, 0.68) in females, compared to the 1946 cohort, and was driven by a much higher weight SD in the 2001 cohort. Conversely, at ages 42/43 years, the Benn parameter was lowest in the 1970 cohort due to a slightly lower weight-height correlation. This difference was estimated to be -0.12 (-0.34, 0.10) in males and -0.15 (-0.42, 0.13) in females, compared to the 1946 cohort.Conclusions: Changes over time in the obesogenic environment appear to have firstly reduced the Benn parameter due to a lowering of the weight-height correlation but secondly and more drastically increased the Benn parameter due to increasing weight variation.

Fetal growth does not modify the relationship of infant weight gain with childhood adiposity and blood pressure in the Southampton women's survey.

Background: Rapid infant weight gain is a risk factor for childhood obesity. This relationship may depend on whether infant weight gain is preceded by in-utero growth restriction.Aim: Examine whether fetal growth modifies the relationship between infant weight gain and childhood adiposity and blood pressure.Subjects and methods: 786 children in the Southampton Women's Survey. We related infant weight gain (weight at 2 years-birth weight) to body mass index (BMI), %body fat, trunk fat (kg), systolic (SBP) and diastolic blood pressure (DBP) at age 6-7 years. Mean estimated fetal weight (EFW) between 19-34 weeks and change in EFW (19-34 weeks) were added to models as effect modifiers.Results: Infant weight gain was positively associated with all childhood outcomes. We found no evidence that these effects were modified by fetal growth (p > .1 for all interaction terms). For example, a 1 standard deviation (SD) increase in infant weight gain was associated with an increase in BMI z-score of 0.51 (95% CI 0.37;0.64) when EFW-change was set at -2 SD-scores compared with an increase of 0.41 (95% CI 0.27;0.54, p(interaction)=.48) when set at 2 SD-scores.Conclusion: The documented adverse consequences of rapid infant weight gain may occur regardless of whether growth was constrained in-utero.

Association of maternal exposures with adiposity at age 4/5 years in white British and Pakistani children: findings from the Born in Bradford study.

AIMS/HYPOTHESIS: There is evidence that, from birth, South Asians are fatter, for a given body mass, than Europeans. The role of developmental overnutrition related to maternal adiposity and circulating glucose in these ethnic differences is unclear. Our aim was to compare associations of maternal gestational adiposity and glucose with adiposity at age 4/5 years in white British and Pakistani children. METHODS: Born in Bradford is a prospective study of children born between 2007 and 2010 in Bradford, UK. Mothers completed an OGTT at 27-28 weeks of gestation. We examined associations between maternal gestational BMI, fasting glucose, post-load glucose and diabetes (GDM) and offspring height, weight, BMI and subscapular skinfold (SSF) and triceps skinfold (TSF) thickness at age 4/5 years, using data from 6060 mother-offspring pairs (2717 [44.8%] white British and 3343 [55.2%] Pakistani). RESULTS: Pakistani mothers had lower BMI and higher fasting and post-load glucose and were twice as likely to have GDM (defined using modified WHO criteria) than white British women (15.8% vs 6.9%). Pakistani children were taller and had lower BMI than white British children; they had similar SSF and lower TSF. Maternal BMI was positively associated with the adiposity of offspring in both ethnic groups, with some evidence of stronger associations in Pakistani mother-offspring pairs. For example, the difference in adjusted mean BMI per 1 kg/m2 greater maternal BMI was 0.07 kg/m2 (95% CI 0.05, 0.08) and 0.10 kg/m2 (95% CI 0.09. 0.11) in white British and Pakistani children, respectively, with equivalent results for SSF being 0.07 mm (95% CI 0.05, 0.08) and 0.09 mm (95% CI 0.08. 0.11) (p for ethnic difference < 0.03 for both). There was no strong evidence of association of fasting and post-load glucose, or GDM, with outcomes in either group. CONCLUSIONS/INTERPRETATION: At age 4/5 years, Pakistani children are taller and lighter than white British children. While maternal BMI is positively associated with offspring adiposity, gestational glycaemia is not clearly related to offspring adiposity in either ethnic group.

Evaluating morphometric body mass prediction equations with a juvenile human test sample: accuracy and applicability to small-bodied hominins.

Body mass is an ecologically and biomechanically important variable in the study of hominin biology. Regression equations derived from recent human samples allow for the reasonable prediction of body mass of later, more human-like, and generally larger hominins from hip joint dimensions, but potential differences in hip biomechanics across hominin taxa render their use questionable with some earlier taxa (i.e., Australopithecus spp.). Morphometric prediction equations using stature and bi-iliac breadth avoid this problem, but their applicability to early hominins, some of which differ in both size and proportions from modern adult humans, has not been demonstrated. Here we use mean stature, bi-iliac breadth, and body mass from a global sample of human juveniles ranging in age from 6 to 12 years (n = 530 age- and sex-specific group annual means from 33 countries/regions) to evaluate the accuracy of several published morphometric prediction equations when applied to small humans. Though the body proportions of modern human juveniles likely differ from those of small-bodied early hominins, human juveniles (like fossil hominins) often differ in size and proportions from adult human reference samples and, accordingly, serve as a useful model for assessing the robustness of morphometric prediction equations. Morphometric equations based on adults systematically underpredict body mass in the youngest age groups and moderately overpredict body mass in the older groups, which fall in the body size range of adult Australopithecus (∼26-46 kg). Differences in body proportions, notably the ratio of lower limb length to stature, influence predictive accuracy. Ontogenetic changes in these body proportions likely influence the shift in prediction error (from under- to overprediction). However, because morphometric equations are reasonably accurate when applied to this juvenile test sample, we argue these equations may be used to predict body mass in small-bodied hominins, despite the potential for some error induced by differing body proportions and/or extrapolation beyond the original reference sample range.

Morphometric panel regression equations for predicting body mass in immature humans.

OBJECTIVES: Predicting body mass is a frequent objective of several anthropological subdisciplines, but there are few published methods for predicting body mass in immature humans. Because most reference samples are composed of adults, predicting body mass outside the range of adults requires extrapolation, which may reduce the accuracy of predictions. Prediction equations developed from a sample of immature humans would reduce extrapolation for application to small-bodied target individuals, and should have utility in multiple predictive contexts. MATERIALS AND METHODS: Here, we present two novel body mass prediction equations derived from 3468 observations of stature and bi-iliac breadth from a large sample of immature humans (n = 173) collected in the Harpenden Growth Study. Prediction equations were generated using raw and natural log-transformed data and modeled using panel regression, which accounts for serial autocorrelation of longitudinal observations. Predictive accuracy was gauged with a global sample of human juveniles (n = 530 age- and sex-specific annual means) and compared to the performance of the adult morphometric prediction equation previously identified as most accurate for human juveniles. RESULTS: While the raw data panel equation is only slightly more accurate than the adult equation, the logged data panel equation generates very accurate body mass predictions across both sexes and all age classes of the test sample (mean absolute percentage prediction error = 2.47). DISCUSSION: The logged data panel equation should prove useful in archaeological, forensic, and paleontological contexts when predictor variables can be measured with confidence and are outside the range of modern adult humans.

The postcranial skeletal maturation of Australopithecus sediba.

OBJECTIVES: In 2008, an immature hominin defined as the holotype of the new species Australopithecus sediba was discovered at the 1.9 million year old Malapa site in South Africa. The specimen (MH1) includes substantial post-cranial skeletal material, and provides a unique opportunity to assess its skeletal maturation. METHODS: Skeletal maturity indicators observed on the proximal and distal humerus, proximal ulna, distal radius, third metacarpal, ilium and ischium, proximal femur and calcaneus were used to assess the maturity of each bone in comparison to references for modern humans and for wild chimpanzees (Pan troglodytes). RESULTS: In comparison to humans the skeletal maturational ages for Au. sediba correspond to between 12.0 years and 15.0 years with a mean (SD) age of 13.1 (1.1) years. In comparison to the maturational pattern of chimpanzees the Au. sediba indicators suggest a skeletal maturational age of 9-11 years. Based on either of these skeletal maturity estimates and the body length at death of MH1, an adult height of 150-156 cm is predicted. DISCUSSION: We conclude that the skeletal remains of MH1 are consistent with an ape-like pattern of maturity when dental age estimates are also taken into consideration. This maturity schedule in australopiths is consistent with ape-like estimates of age at death for the Nariokotome Homo erectus remains (KMN-WT 15000), which are of similar postcranial immaturity to MH1. The findings suggest that humans may have distinctive and delayed post-cranial schedules from australopiths and H. erectus, implicating a recent evolution of somatic and possibly life history strategies in human evolution.

A comparison of skeletal maturity assessed by radiological and ultrasonic methods.

OBJECTIVES: The estimation of skeletal maturity is a useful tool in pediatric practice to determine the degree of delay or advancement in growth disorders and the effectiveness of treatment in conditions that influence linear growth. Skeletal maturity of children is commonly assessed using either Greulich-Pyle (GP) or Tanner-Whitehouse methods (TW2 and TW3). However, a less invasive ultrasonic method, that does not use ionizing radiation, has been suggested for use in epidemiological studies of skeletal maturity. The main purpose of the present study was to determine the accuracy of an ultrasonic method based on the GP maturity indicators compared to the standard GP radiographic method. METHODS: Skeletal maturity of 1502 healthy children, aged from 6 to 18 years, was estimated by quantitative ultrasound and compared to GP bone ages estimated from left hand and wrist radiographs of a subsample of 47 randomly selected participants. RESULTS: The ultrasonic bone age estimation demonstrated very strong correlations with all the radiological age estimations. The correlation coefficients ranged between 0.895 and 0.958, and the strongest correlation of ultrasonic skeletal maturity estimation was found with the Tanner-Whitehouse RUS method. The ultrasonic bone age estimation is suggested for use between the chronological ages of 8.5-16.0 years in boys and 7.5-15.0 years in girls. CONCLUSIONS: The ultrasonic bone age estimation is suggested for use in epidemiological surveys since the sensitivity for screening for not normal bone development is appropriate, at least within the 8-15 years age interval.

The objective measurement of physical activity and sedentary behaviour in 2-3 year olds and their parents: a cross-sectional feasibility study in the bi-ethnic Born in Bradford cohort.

BACKGROUND: The reported lower physical activity (PA) levels of British South Asians (SA) are suggested as a key influence in their increased risk of non-communicable diseases compared to their White British peers. Differences in objectively measured PA and sedentary behaviour (SB) between these ethnic groups have been observed during childhood (ages: 8-10 years). However, no information exists on objectively measured PA/SB in younger children, or how early in life differences in these behaviours emerge. Assessing PA/SB in the Born in Bradford (BIB) cohort study provides an opportunity to address such gaps in the literature, but previous studies have found recruiting and retaining SA participants challenging, and the feasibility of using accelerometers with SA children and parents is unknown. This study investigated the feasibility of recruiting and objectively measuring the habitual PA/SB of 2-3 year old SA and White British children and parents from the BIB study. METHODS: Families were informed about the study during routine BIB assessments. Consenting families were visited at home for anthropometry measurements, interviews, material delivery and collection. Participants (child and parents) were instructed to wear the ActiGraph GT3X+ for 8 days. Descriptive statistics were computed, and ethnic differences tested (Chi-square) for recruitment uptake and compliance. RESULTS: 160 families (30 % SA) provided contact details, and 97 (22 % SA) agreed to enter the study. White British families showed lower refusal and higher intake into the study than SA (p = 0.006). Of 89 children issued with an accelerometer, 34 % complied with the 8-day protocol (significantly less SA; p = 0.015) and 75 % provided enough days (≥ 3) to assess habitual PA/SB (no ethnic differences). Parental rates of compliance with the protocol did not differ between ethnicities. Issues experienced with the protocol and accelerometer use, and successful implementation strategies/procedures are presented. CONCLUSIONS: Although greater efforts may be required to recruit SA, those consenting to participate were as likely as White British to provide enough data to assess habitual PA/SB. The issues and successful strategies reported in this feasibility study represent valuable information for planning future studies, and enhance recruitment and compliance with accelerometer protocols in SA and White British toddlers and parents.

Can maturity indicators be used to estimate chronological age in children?

CONTEXT: There is widespread concern over the use of maturity indicators to estimate chronological age in children. OBJECTIVE: To review the definition of maturity indicators, the criteria governing their identification and use and the problems of their interpretation. METHODS: The development of maturity indicators, the criteria for their selection and the relationship of maturity to chronological age is critically reviewed. RESULTS AND CONCLUSIONS: Maturity indicators are not related to the passage of chronological time, but to the progression of the individual from an immature to a mature state. They are discrete events in a continuous process or a series of processes (e.g. skeletal, sexual, dental, etc.) that highlight uneven maturation within the individual, the independence of maturational processes, sexual dimorphism and the relationship of maturity to size. The use of a timescale of development causes considerable problems in translating biological maturity into a developmental scale. One "year" of maturational time does not equate to 1 year of chronological time and, thus, the passage of time determined by developmental rather than temporal landmarks is both variable and inconsistent. Chronological age determination was not the aim of maturational assessment and, thus, its widespread use as an age determinant poses considerable interpretive challenges.

Modelling foetal growth in a bi-ethnic sample: results from the Born in Bradford (BiB) birth cohort.

BACKGROUND: Attempts to explain the increased risk for metabolic disorders observed in South Asians have focused on the "South Asian" phenotype at birth and subsequent post-natal growth, with little research on pre-natal growth. AIM: To identify whether divergent growth patterns exist for foetal weight, head (HC) and abdominal circumferences (AC) in a sample of Pakistani and White British foetuses. SUBJECTS AND METHODS: Models were based on 5553 (weight), 5154 (HC) and 5099 (AC) foetuses from the Born in Bradford birth cohort. Fractional polynomials and mixed effects models were employed to determine growth patterns from ~15 weeks of gestation-birth. RESULTS: Pakistani foetuses were significantly smaller and lighter as early as 20 weeks. However, there was no ethnic difference in the growth patterns of weight and HC. For AC, Pakistani foetuses displayed a trend for reduced growth in the final trimester. CONCLUSION: As the pattern of weight and HC growth was not significantly different during the period under investigation, the mechanism culminating in the reduced Pakistani size at birth may act earlier in gestation. Reduced AC growth in Pakistanis may represent reduced growth of the visceral organs, with consequences for post-natal liver metabolism and renal function.

Multi-level modelling of longitudinal child growth data from the Birth-to-Twenty Cohort: a comparison of growth models.

BACKGROUND: Different structural and non-structural models have been used to describe human growth patterns. However, few studies have compared the fitness of these models in an African transitioning population. AIM: To find model(s) that best describe the growth pattern from birth to early childhood using mixed effect modelling. SUBJECTS AND METHODS: The study compared the fitness of four structural (Berkey-Reed, Count, Jenss-Bayley and the adapted Jenss-Bayley) and two non-structural (2nd and 3rd order Polynomial) models. The models were fitted to physical growth data from an urban African setting from birth to 10 years using a multi-level modelling technique. The goodness-of-fit of the models was examined using median and maximum absolute residuals, Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). RESULTS: There were variations in how the different models fitted to the data at different measurement occasions. The Jenss-Bayley and the polynomial models did not fit well to growth measurements in the early years, with very high or very low percentage of positive residuals. The Berkey-Reed model fitted consistently well over the study period. CONCLUSION: The Berkey-Reed model, previously used and fitted well to infancy growth data, has been shown to also fit well beyond infancy into childhood.