Roland Hauspie

Maturational delay and temporal growth retardation in asthmatic boys

Growth in height, bone age, and sexual maturation have been studied in asthmatic boys 2 to 20 yr of age. The mean pattern of growth in height has been analyzed mixed-longitudinally in 531 patients (1,754 measures) and seemed to be determined by a delay in physiologic maturation. The asthmatic boys growth in height showed no retardation during infancy, a small but consistent retardation during childhood, a more pronounced delay at adolescence, and a catch-up growth toward adulthood. The mean adolescent growth spurt is delayed by about 1.3 yr. Bone age has been analyzed mixed-longitudinally in a subsample of 370 patients (660 observations) and showed a slight retardation at all ages between 6 and 13 yr. Development of pubic hair of 91 subjects analyzed cross-sectionally was definitely retarded when compared to adequate reference data. Evidence was given that factors secondary to the asthmatic syndrome are involved in the retardation of growth and development.

Growth of Belgian and Norwegian children compared to the WHO growth standards: prevalence below −2 and above +2 SD and the effect of breastfeeding

Background New national growth references have been published in Belgium and Norway. The WHO recommends universal use of their 2006 Child Growth Standards based on data from breastfed children. Objective To compare the growth of Belgian and Norwegian children with the WHO standards. Participants 6985 children 0–5 years of age from Belgium and Norway. Design Proportion of children below −2 SD and above +2 SD of the WHO standards was calculated for length/height, weight, body mass index and head circumference. Average SD scores of exclusively breastfed children of non-smoking mothers were compared with national reference data and with the WHO standards. Results Generally, the number of Belgian and Norwegian children below −2 SD lines of the WHO standards was lower and above +2 SD higher than expected. The largest differences were for head circumference (0.97% Belgian and 0.18% Norwegian children below −2 SD, 6.55% Belgian and 6.40% Norwegian children above +2 SD) and the smallest for length/height (1.25% Belgian and 1.43% Norwegian children below −2 SD, 3.47% Belgian and 2.81% Norwegian children above +2 SD). The growth pattern of breastfed children of non-smoking mothers was in both countries more alike the local national growth references than the WHO standards. Conclusions There are significant deviations in the proportion of children outside normal limits (±2 SD) of the WHO standards. This was true for all children, including those who were exclusively breastfed. Hence, adoption of the WHO growth charts could have consequences for clinical decision-making. These findings advocate the use of national references in Belgium and Norway, also for breastfed children.

A longitudinal study of the growth in height of boys and girls of West Bengal (India) aged six months to 20 years

This study is the first Indian longitudinal growth survey from early childhood to maturity. The heights of 303 boys and 260 girls, from middle-class families in a semi-urban area south of Calcutta, were measured at regular intervals over periods of up to 14 years (between 1952 and 1966). The data were analysed using appropriate mixed longitudinal and curve-fitting techniques. Growth in height of these middle-class Bengali children, who are not a representative sample of the Indian population, is slightly above the national Indian Council of Medical Research Standards. In both sexes, mean heights are below the 10th centile line of the British standards from an early age onwards, mainly due to a smaller prepubertal growth. The adolescent growth spurt in the Indians similar to that seen in British children, as is the age at which it occurs (peak height velocity at 14.0 years in boys, 12.5 years in girls). The sex difference of 14.0 cm in adult stature is attributable to a greater adolescent gain in the boys of 6.0 cm, a greater height in boys at the girls age at take-off of 3.3 cm and a gain in height by the boys of 4.7 cm between the girls and boys ages at take-off.

Growth references for Norwegian children

BACKGROUNDnThe growth charts currently used in Norway, are based on measurements from the 1970s and 80s. New data are available from the Bergen Growth Study collected in 2003 - 6. In 2006, WHO published international charts for 0-5 year-old children.nnnMATERIAL AND METHODSnNew growth charts based on data from the Bergen Growth Study and the Medical Birth Registry of Norway are presented for children aged 0-19 years. These were compared with existing references and with the WHO curves.nnnRESULTSnNorwegian children aged 0-4 years have length, height and weight measurements that are only marginally different from those in the Norwegian growth charts in current use. In older children there has been an increase in the 50-percentile for height up to 3.4 cm in boys and 2.5 cm in girls. For children older than four years, weight for height has increased, especially for the upper percentiles. The percentile lines in the new Norwegian reference are generally positioned above the WHO standard for weight at birth, and for length/height, weight and head circumference in the age group 6 months to 5 years.nnnINTERPRETATIONnThe secular trends in growth mirror the need for new charts. The fact that Norwegian children differ from the WHO standards may reflect population differences relating to environment or growth potential between the populations.

Testing for the presence of genetic variance in factors of face measurements of Belgian twins.

Factor analysis with VARIMAX rotation was used to analyse 15 face measurements in Belgian same-sexed twins, aged 18-25 years: 39 dizygotic and 57 monozygotic male pairs and 42 dizygotic and 67 monozygotic female paris. According to Christians model, we used the ratio of the within-mean squares of dizygotic and monozygotic pairs to test for the presence of a genetic component in the variance of the facial dimensions and of all the rotated factors were statistically significant (P less than 0.05), suggesting a genetic component in the variance. The probabilities of the F values were generally lower in males than in females. The factor analysis yielded five main factors of which three were well separated: face height, ear size and lips. The two others were breadth factors, but were less clearly defined, probably due to a bad selection of variables. A comparison of the F values of the factors with those of their contributing variables seemed to indicate that well-defined factors may better describe genetically determined structures than the original variables can.

Longitudinal Growth in Height, Weight, and Bone Age of Guatemalan Ladino and Indian Schoolchildren

Three longitudinal samples of Guatemalan schoolchildren are compared for amounts and rates of growth in height, weight, and bone age. The samples include children of two ethnic backgrounds: Ladinos, Spanish‐speaking people of, generally, Western cultural orientation; and Indians, people of Mayan cultural descent. The Indians are of very low socioeconomic status (SES) and attend a public school in a rural village. The Ladinos come from two SES groups living in Guatemala City, one of high SES attending a private school and the other of low SES attending a public school. Graphical and statistical analyses show that for all samples of boys and girls there are generally, significant differences between samples (high SES>low SES>Indian) for amounts of growth in height, weight, and bone age. Boys show significant differences in rates of growth between samples, with the high SES sample growing more rapidly than the two low SES samples. Girls show significant differences in the rate of growth in height, but not in the rate of growth in weight or bone age. For Both boys and girls, rates of growth in height and weight differ more between samples than does rate of Skeltal development. These results demonstrate that (1) SES‐related deficits in growth are cumulative during childhood and early adolescence, that (2) rates of growth for boys are, generally, more sensitive to the influence of SES than are the growth rates of girls, and that (3) childhood growth deficits of low SES children of low SES children are likely to carry over into adulthood.

On the independence of adult stature from the timing of the adolescent growth spurt

Longitudinal studies have shown repeatedly that little or no correlation exists between the timing of the pubertal spurt in stature and adult stature (AS). However, the possibility seems to have been overlooked that such near‐zero correlations may, at least theoretically, be an artefact resulting from two opposite tendencies that cancel each other out: a hypothetical “biological” tendency for early maturers to end up as slightly shorter adults and a socially induced tendency, resulting from the existence of social gradients in growth, for accelerated maturation to be accompanied by taller A.S. Data of the Wroclaw Growth Study (355 fitted growth curves) were used to see whether making a sample socially more homogeneous produces any increase in the correlation between age at PHV and AS. No such effects were found. Thus the validity of the view is confirmed that genes controlling the timing of the spurt also affect the shape of the growth curve in such a way that the shorter time available for completion of growth in the early maturers is compensated for by a greater intensity of the spurt itself.

Adolescence: Somatic Growth and Sex Differences

This chapter discusses the various approaches in modeling human growth. Growth in adolescence is characterized by the presence of an adolescent, or pubertal, growth spurt. The age at takeoff varies considerably, among populations, individuals, and sexes. Maximum velocity of height-increase is reached within 3–3.5 years after the onset of the spurt. The difference in age at takeoff and age at peak velocity can be used as a measure of the duration of the adolescent spurt. After having reached a peak, the growth velocity rapidly decreases, inducing the end of the growth cycle at full maturity, around 16–17 years for girls and 18–19 years for boys in Western populations. There is a wide variation among populations, individuals and the two sexes as to the attained size at each age, the timing of events such as adolescent growth spurt, and the age at which mature size is reached. The growth curve of height is typical for all post-cranial skeletal dimensions of the body. Various mathematical models have been proposed to estimate a smooth growth curve on the basis of a set of discrete measurements of growth of the same subject over time. The adult sex differences in longitudinal body dimensions are attributable mainly to the boys longer prepubertal growth cycle.

Heritability variations of morphometric traits in West Bengal (India) children aged 4-19 years: a mixed-longitudinal growth study.

Background: Longitudinal and semi-longitudinal growth studies on siblings reflecting heritability changes during growth are very scarce. Moreover, studies of variables other than height, weight and BMI are virtually non-existent. Aim: The study compared changes in the heritability of six body lengths, four body breadths, and three indices between ages 4 and 19 years on the basis of a mixed-longitudinal sample of siblings, and examined whether heritability estimates change during the growth period. The data consisted of 238 brothers and 214 sisters from 134 middle-class nuclear families living in Kolkata (India). The analysis of sibling correlation was performed by maximum likelihood. The age-related patterns of heritabilities of the various traits were described by a cubic spline. Results: The heritability was very high and significant in most traits, and at all considered ages. Mean heritability in the 10 morphometric traits was 69.3%, which was higher than the heritability values for the three indices. Conclusions: These results confirmed the existence of age-related trends in heritability of the considered morphometric traits. The sharp decline of the heritabilities at adolescence in most of the morphometric traits, and the acromio-iliac index in particular, may be due to the large inter-individual variation in the age at which the adolescent growth spurt is reached in both sexes.

Determinants of growth in body length from birth to 6 years of age: A longitudinal study of Lublin children

The effect of determinants of growth in body length from birth to 6 years of age were studied in a longitudinal sample of 59 male and 70 female infants from Lublin, Poland. Structural equation modeling (SEM) was used to study the effects of gender of the child, occupation of the parents, the educational level of the parents, per capita income, the stature of the parents, and the weight of the mother on body length at birth and at 1, 2, 3, and 6 years of age. Significant sex differences in length were observed at birth and during the first 2 years of postnatal life, but not in the period between 3 and 6 years of age. Socioeconomic status (SES), expressed as a latent variable in the SEM, was not related to body length at birth but was significantly related to body length during infancy and, to a lesser extent, to body length during childhood. Paternal stature was not related to body length at birth and during infancy, but was significantly related to body length from 3 years onwards. Maternal stature was significantly related to body length at birth and at 1 year of age, but not thereafter, while maternal weight was significantly related to body length at birth only.