Are inequalities in height narrowing? Comparing effects of social class on height in two generations

Age at peak height velocity in Polish adolescents: Effect of socioeconomic factors

Age at peak height velocity (APHV) is an indicator of maturity timing which is applicable to both sexes, and which is influenced by environmental factors. The objective of this study was to assess variation in APHV associated with several indicators of socioeconomic status (SES) in a longitudinal sample of Polish adolescents. The sample included 739 boys born in 1983 and followed annually from 12 to 16 years, and 597 girls born in 1985 and followed annually from 9 to 13 years. The height records were fitted with the SITAR model to estimate APHV. SES was estimated using principal component analysis of indicators of familial status based on parental education, family size, living conditions and household possessions. Statistical analyses included analysis of variance (one-way for general SES and three-way for parental education and family size) and Tukey post-hoc tests for unequal samples. General SES (p <.001) and family size (p < .05) significantly influenced APHV among boys, while only maternal education (p < .05) significantly influenced APHV among girls. Among youth from families of higher SES, as defined by the respective indicators, APHV was attained significantly earlier, on average, than in peers from families of lower SES. Overall, the results showed a sex-dependent effect of SES on APHV, and highlighted the influence of favorable socioeconomic conditions for optimal growth and maturation during adolescence.

Latent growth analysis of children's height growth trajectories

Characterizing and quantifying the trajectories of variables of interest through time in their field of study is of interest to a range of disciplines. The aim of this study was to investigate the growth speed in height of children and its determinants. A total of 3401 males and 3200 females from four low- and middle-income countries with measured height on five occasions from 2002 to 2016 were included in the study. Data were analyzed using a latent growth model. The results of the study reported that children in four low- and middle-income countries exhibited substantial growth inequalities. There was a significant gender difference in change of growth with males had a higher baseline, rate of change, and acceleration in height growth than females. Comparing the component of slopes across countries, the growth change inequalities were observed among children. These inequalities were statistically significant, with the highest rate of change observed in Peru and Vietnam.

Short men in poor lands: The agrarian workers from southwestern Spain in anthropometric perspective

With a sample of heights of almost 60,000 men, born between 1855 and 1979 and recruited between 1876 and 2000, our work analyzes the nutritional gap between the agrarian and non-agrarian population in Extremadura, a Spanish region located among the poorest ones in Europe. The analysis reveals that this difference is not only statistically significant, but also tends to increase as the average stature of the active population grows. Among the causes of the agrarian height penalty, our article focuses mainly on the economic differences. However, the research also insists on the roots of these differences, especially those linked to the adverse physical conditions of the territory, the dynamics of the Christian conquest in the Middle Ages and the strong and persistent concentration of land ownership in the region. In short, this paper concludes that the anthropometric gap between agrarian and non-agrarian workers is due not only to economic causes, but also to geographical, historical and institutional reasons.

Studying latent change process in height growth of children in Ethiopia, India, Peru and Vietnam

BACKGROUND

Anthropometric measurements of healthy children differ in different parts of the world due to the diverse ethnicity and cultural backgrounds of families. In longitudinal studies, appropriate modeling of repeated anthropometric measures can improve the understanding of patterns of change, determinants of patterns, and variations in patterns of change over time. The objective of this study was to examine the latent change in physical height of children in Ethiopia, India, Peru, and Vietnam.

METHOD

Longitudinal data of 6601 children aged 1 to 15 years were obtained from the Young Lives cohort study. The data were analyzed using a latent basis growth curve model.

RESULTS

The findings of the study revealed that the rates of growth did not remain constant across the time intervals, which indicates the nonlinearity of the growth trajectory over time. For instance, children had the highest rate of growth between age 1 and 5 years, then between age 8 and 12 years, and a low rate of growth was observed between age 12 and 15 years. At the first measurement occasion (age 1 year) females were 0.826 cm (p < 0.0001) times shorter than males. The mean height at one year of age ranged from 72.13 cm in Ethiopia to 72.62 cm in India. Children in India and Vietnam had higher mean height at age one year. However, no significant difference in mean height at age one year was found between Ethiopian and Peruvian children, ([Formula: see text]). Peruvian and Vietnamese children grew at a faster rate, while Indian children grew at a slower rate than Ethiopian children.

CONCLUSION

We found substantial latent growth variations among children in four low- and middle-income countries. The latent trajectories differed by gender and country. The outcomes of the study could aid in detecting inequalities in children's height growth.

Socio-economic disparities in child-to-adolescent growth trajectories in China: Findings from the China Health and Nutrition Survey 1991–2015

Backgrounds

Socio-economic disparities in growth trajectories of children from low-/middle-income countries are poorly understood, especially those experiencing rapid economic growth. We investigated socio-economic disparities in child growth in recent decades in China.

Methods

Using longitudinal data on 5095 children/adolescents (7–18 years) from the China Health and Nutrition Survey (1991–2015), we estimated mean height and BMI trajectories by socio-economic position (SEP) and sex for cohorts born in 1981–85, 1986–90, 1991–95, 1996–2000, using random-effects models. We estimated differences between high (urbanization index ≥median, household income per capita ≥median, parental education ≥high school, or occupational classes I–IV) and low SEP groups.

Findings

Mean height and BMI trajectories have shifted upwards across cohorts. In all cohorts, growth trajectories for high SEP groups were above those for low SEP groups across SEP indicators. For height, socio-economic differences persisted across cohorts (e.g. 3.8cm and 2.9cm in earliest and latest cohorts by urbanization index for boys at 10 year, and 3.6cm and 3.1cm respectively by household income). For BMI, trends were greater in high than low SEP groups, thus socio-economic differences increased across cohorts (e.g. 0.5 to 0.8kg/m² by urbanization index, 0.4 to 1.1kg/m² by household income for boys at 10 year). Similar trends were found for stunting and overweight/obesity by SEP. There was no association between SEP indicators and thinness.

Interpretation

Socio-economic disparities in physical growth persist among Chinese youth. Short stature was associated with lower SEP, but high BMI with higher SEP. Public health interventions should be tailored by SEP, in order to improve children's growth while reducing overweight/obesity.

Funding

MG is supported by UCL Overseas Research Scholarship and China Scholarship Council for her PhD study. WJ is supported by a UK Medical Research Council (MRC) New Investigator Research Grant (MR/P023347/1) and acknowledges support from the National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, which is a partnership between University Hospitals of Leicester NHS Trust, Loughborough University, and the University of Leicester.

Height and health in late eighteenth-century England

Adult stature has become a widely used indicator of childhood nutritional status in historical populations and may provide insights into health inequalities that are not discernible in mortality rates. However, most pre-twentieth-century British data on heights suffer from selection biases. Here we present unique evidence on heights of adult males by occupation from an unbiased sample of adult males in Dorset in 1798-99. The mean height of fully grown (married) men was very similar to that of older military recruits, and our sample therefore confirms the taller stature of English males relative to males of other European countries in the same period. In contrast to previous evidence of negligible or U-shaped socio-economic gradients in mortality in this period, we found a fairly linear gradient in height by socio-economic status, that is similar in magnitude to class differences in adult height among English males born in the mid-twentieth century.Supplementary material for this article is available at: https://doi.org/10.1080/00324728.2020.1823011.

Regional differences in short stature in England between 2006 and 2019: A cross-sectional analysis from the National Child Measurement Programme

BACKGROUND

Short stature, defined as height for age more than 2 standard deviations (SDs) below the population median, is an important indicator of child health. Short stature (often termed stunting) has been widely researched in low- and middle-income countries (LMICs), but less is known about the extent and burden in high-income settings. We aimed to map the prevalence of short stature in children aged 4-5 years in England between 2006 and 2019.

METHODS AND FINDINGS

We used data from the National Child Measurement Programme (NCMP) for the school years 2006-2007 to 2018-2019. All children attending state-maintained primary schools in England are invited to participate in the NCMP, and heights from a total of 7,062,071 children aged 4-5 years were analysed. We assessed short stature, defined as a height-for-age standard deviation score (SDS) below -2 using the United Kingdom WHO references, by sex, index of multiple deprivation (IMD), ethnicity, and region. Geographic clustering of short stature was analysed using spatial analysis in SaTScan. The prevalence of short stature in England was 1.93% (95% confidence interval (CI) 1.92-1.94). Ethnicity adjusted spatial analyses showed geographic heterogeneity of short stature, with high prevalence clusters more likely in the North and Midlands, leading to 4-fold variation between local authorities (LAs) with highest and lowest prevalence of short stature. Short stature was linearly associated with IMD, with almost 2-fold higher prevalence in the most compared with least deprived decile (2.56% (2.53-2.59) vs. 1.38% (1.35-1.41)). There was ethnic heterogeneity: Short stature prevalence was lowest in Black children (0.64% (0.61-0.67)) and highest in Indian children (2.52% (2.45-2.60)) and children in other ethnic categories (2.57% (2.51-2.64)). Girls were more likely to have short stature than boys (2.09% (2.07-2.10) vs. 1.77% (1.76-1.78), respectively). Short stature prevalence declined over time, from 2.03% (2.01-2.05) in 2006-2010 to 1.82% (1.80-1.84) in 2016-2019. Short stature declined at all levels of area deprivation, with faster declines in more deprived areas, but disparities by IMD quintile were persistent. This study was conducted cross-sectionally at an area level, and, therefore, we cannot make any inferences about the individual causes of short stature.

CONCLUSIONS

In this study, we observed a clear social gradient and striking regional variation in short stature across England, including a North-South divide. These findings provide impetus for further investigation into potential socioeconomic influences on height and the factors underlying regional variation.

Intergenerational change in anthropometry of children and adolescents in the New Delhi Birth Cohort

BACKGROUND

A comparison of the anthropometry of children and adolescents with that of their parents at the same age may provide a more precise measure of intergenerational changes in linear growth and body mass index (BMI).

METHODS

New Delhi Birth Cohort participants (F1), born between 1969 and 1972, were followed up for anthropometry at birth and at 6-monthly intervals until 21 years of age. At variable intervals 1447 children, aged 0-19 years (F2) and born to 818 F1 participants, were measured (weight and height), providing 2236 sets of anthropometries. Intergenerational changes (F2-F1) in height and BMI [absolute and standard deviation (SD) units] were computed by comparing children with their parents at corresponding ages.

RESULTS

F2 children were taller (P < 0.001) than their parents at corresponding ages; the increase {mean [95% confidence interval)CI)] World Health Organization SD units} was 0.97 (0.83, 1.11), 1.21 (1.10, 1.32), 1.09 (0.98, 1.19), 1.10 (1.00, 1.21) and 0.75 (0.65, 0.85) for age categories of 0-5, 5-7.5, 7.5-10, 10-12.5 and >12.5 years, respectively. In absolute terms, this increase ranged from 3.5 cm (0-5-year-olds) to 7.5 cm (10-12.5-year-olds). The corresponding increases in BMI SD scores were 0.32 (0.18, 0.47), 0.60 (0.45, 0.75), 1.13 (0.99, 1.27), 1.30 (1.15, 1.45) and 1.00 (0.85, 1.15), respectively. The absolute BMI increase ranged from 1-3 kg/m2 at >5 years age to ∼3 kg/m2 at >10-years of age. The intergenerational increases were comparable in both sexes, but were greater in children born and measured later. A positive change in socioeconomic status was associated with an increase in height across the generations.

CONCLUSIONS

Children and adolescents, throughout the ages 0-19 years, have become considerably taller and have a higher BMI than their parents at corresponding ages in an urban middle-class Indian population undergoing socioeconomic improvements.

Analysis of factors contributing to occupational health inequality in Korea: a cross-sectional study using nationally representative survey data

Background

Despite the consensus that higher occupational classes tend to have better health and lower mortality rates, one study has reported reversed occupational gradients in mortality rates among Korean men after the economic crisis in the late 2000s. To examine these patterns of health inequality in more detail, we investigated the tendency of occupational gradients in socioeconomic position and multiple pathway indicators known to affect mortality in Korea.

Methods

We used data from 4176 men aged 35–64 in Korea derived from the 2007–2009 and 2013–2015 Korean National Health and Nutrition Examination Surveys. We compared the age-standardized prevalence and age-adjusted mean values of each contributing factor to health inequality among occupational groups, which are divided into upper non-manual workers, lower non-manual workers, manual workers, and others. Contributing factors included childhood and adulthood socioeconomic position indicators, biological risk factors, health behaviors, psychosocial factors, and work environment.

Results

Upper non-manual workers had prominently higher levels of education, income, parental education, and economic activity than lower non-manual and manual workers. The rates of smoking and high-risk alcohol consumption were lower, and the rate of weight control activities was higher, in the non-manual classes. Further, the rates of depression and suicidal ideation were lower, and perceptions of the work environment were more favorable, among non-manual workers than among their manual counterparts.

Conclusions

We detected occupational inequality in a wide range of socioeconomic positions and pathway indicators in Korea with consistently favorable patterns for upper non-manual workers. These occupational gradients do not support the previously reported reversed pattern of higher mortality rates in non-manual groups versus in the manual job class in Korea.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-021-00638-9.

Secular trend and social variation in height of Polish schoolchildren between 1966 and 2012

AIM

To assess secular trend and changes in social inequalities of children's height across nearly 50 years, when vast socio-political changes took place in Poland.

METHODS

Data on schoolchildren aged 7-18 years were collected in 1966, 1978, 1988 and 2012 in Poland. Height was standardised for age using the LMS method. Socio-economic status (SES) was based on 4 factors: urbanisation level, mother's and father's education, and family size (number of children). Statistics included 2-way ANOVA with post hoc Tukey's test and effect size calculations.

RESULTS

Positive secular trend in height was observed across all years. All analysed SES factors had significant effect on height which differed depending on SES category and year of Survey. Differences in height between extreme categories of SES factors decreased gradually, starting from 1978. However, only general SES in girls and urbanisation level in both sexes became insignificant in 2012.

CONCLUSION

Improvement of living conditions across nearly 50 years was reflected in the secular trend in children's height. Despite this improvement, however, the biological effects of social inequalities, visible in differences in height, to some extent, are still present in Poland.

Reducing socioeconomic differences in anthropometric characteristics among young Polish women

The aim of this paper was to evaluate the socioeconomic differences in adult anthropometric parameters of young women in Poland. The study was cross-sectional and conducted in the years 2015 to 2018 among 1257 women aged 19-24 years. The heights, weights, wrist widths and waist, hip and chest circumferences of the subjects were measured. Body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), waist-to-chest ratio (WCR) and chest-to-height ratio (CHtR) were calculated. A survey was conducted to collect data on the women's socioeconomic characteristics. The application of the Generalized Linear Model (GLM) including all socioeconomic indicators (urbanization level of place of residence in childhood, parental education, number of siblings, material conditions) revealed no significant association of these with any of the analysed anthropometric traits. The results of the logistic regression showed no significant differences in the risk of underweight, too low abdominal adiposity or too high abdominal adiposity. However, the risk of overweight and obesity was significantly affected by the degree of urbanization of the women's place of residence in childhood and by their number of siblings. The results show that the socioeconomic factors that once had a significant influence on anthropometric traits currently do not play such an important role. This change can be explained by the equalization of living conditions and lifestyles of individual social groups in Poland.

Secular Trends in Height, Body Mass and Mean Menarche Age in Romanian Children and Adolescents, 1936-2016

Secular trends in anthropometric parameters have been documented in most European countries, but no data is available regarding Romanian. The aim of the study was to calculate secular trend in height, body mass and mean menarche age for Romanian children and adolescents.

METHODS

A secondary data analysis was performed using ten data sets for urban and eight data sets for rural boys and girls, age 5-15 years, covering 80 years (1936 to 2016). Secular trend in height (cm/decade), body mass(kg/decade) and mean menarche age (years) were calculated.

RESULTS

Overall, there was a positive secular trend for height in both genders, which parallels the gross domestic product (GDP)/capita difference, more pronounced in boys, across all age-groups, with a maximum for 15 years-old boys (~3 cm/decade) and 13 years-old girls (~2 cm/decade). Body mass trend was also positive, more accentuated in the rural population. Mean age at menarche was higher in rural compared to urban girls, had a negative trend with the disappearance of the difference in the latest available data set (2013).

CONCLUSION

In summary, an overall positive and ongoing secular trend in height and body mass was documented in Romanian children and adolescents, especially for the pubertal age-range, in concordance to other western countries, but out of phase by approximately 20 years.

Poverty and a child's height development during early childhood: A double disadvantage? A study of the 2006-2009 birth cohorts in Flanders

Introduction

Poverty is a well-known risk factor for a child’s health and development. This paper aimed to establish whether poverty negatively affected both intra-uterine growth and early childhood growth, i.e., whether children facing poverty were at a double disadvantage.

Methods

For this study, we made use of routinely collected data on child development throughout early childhood from the 2006–2009 birth cohorts in Kind & Gezin’s Ikaros database collected during 2,605,975 consultations with 273,935 children from birth to 730 days old. Indicators for child development at birth were gestational age and height-at-birth. A standardized height-for-age indicator captured height development throughout early childhood. A multidimensional indicator measured the risk of poverty. For the analysis of development at birth, we used linear and logistic regression; for the analysis of height development during early childhood, we estimated linear and logistic growth curve models.

Results

The risk of poverty negatively affected both gestational age and height-at-birth. Throughout early childhood, we observed a negative relation between the risk of poverty and height-for-age indicators. However, the effect varied throughout childhood. Children at risk of poverty (over)compensated for their smaller stature at birth, and between ages 6 and 18 months, approximately, the negative effects of risk of poverty decreased substantially or disappeared. However, towards the end of the period studied, children born in households at risk of poverty started to lag again in height development.

Conclusion

This study found that the risk of poverty indeed negatively affected a child’s growth, both in utero and in early childhood. However, the results suggest that developmental lags later in childhood were not merely an extension of such lags at birth.

Socioeconomic inequalities in childhood and adolescent body-mass index, weight, and height from 1953 to 2015: an analysis of four longitudinal, observational, British birth cohort studies

BACKGROUND

Socioeconomic inequalities in childhood body-mass index (BMI) have been documented in high-income countries; however, uncertainty exists with regard to how they have changed over time, how inequalities in the composite parts (ie, weight and height) of BMI have changed, and whether inequalities differ in magnitude across the outcome distribution. Therefore, we aimed to investigate how socioeconomic inequalities in childhood and adolescent weight, height, and BMI have changed over time in Britain.

METHODS

We used data from four British longitudinal, observational, birth cohort studies: the 1946 Medical Research Council National Survey of Health and Development (1946 NSHD), 1958 National Child Development Study (1958 NCDS), 1970 British Cohort Study (1970 BCS), and 2001 Millennium Cohort Study (2001 MCS). BMI (kg/m2) was derived in each study from measured weight and height. Childhood socioeconomic position was indicated by the father's occupational social class, measured at the ages of 10-11 years. We examined associations between childhood socioeconomic position and anthropometric outcomes at age 7 years, 11 years, and 15 years to assess socioeconomic inequalities in each cohort using gender-adjusted linear regression models. We also used multilevel models to examine whether these inequalities widened or narrowed from childhood to adolescence, and quantile regression was used to examine whether the magnitude of inequalities differed across the outcome distribution.

FINDINGS

In England, Scotland, and Wales, 5362 singleton births were enrolled in 1946, 17 202 in 1958, 17 290 in 1970, and 16 404 in 2001. Low socioeconomic position was associated with lower weight at childhood and adolescent in the earlier-born cohorts (1946-70), but with higher weight in the 2001 MCS cohort. Weight disparities became larger from childhood to adolescence in the 2001 MCS but not the earlier-born cohorts (pinteraction=0·001). Low socioeconomic position was also associated with shorter height in all cohorts, yet the absolute magnitude of this difference narrowed across generations. These disparities widened with age in the 2001 MCS (pinteraction=0·002) but not in the earlier-born cohorts. There was little inequality in childhood BMI in the 1946-70 cohorts, whereas inequalities were present in the 2001 cohort and widened from childhood to adolescence in the 1958-2001 cohorts (pinteraction<0·05 in the later three cohorts but not the 1946 NSHD). BMI and weight disparities were larger in the 2001 cohort than in the earlier-born cohorts, and systematically larger at higher quantiles-eg, in the 2001 MCS at age 11 years, a difference of 0·98 kg/m2 (95% CI 0·63-1·33) in the 50th BMI percentile and 2·54 kg/m2 (1·85-3·22) difference at the 90th BMI percentile were observed.

INTERPRETATION

Over the studied period (1953-2015), socioeconomic-associated inequalities in weight reversed and those in height narrowed, whereas differences in BMI and obesity emerged and widened. These substantial changes highlight the impact of societal changes on child and adolescent growth and the insufficiency of previous policies in preventing obesity and its socioeconomic inequality. As such, new and effective policies are required to reduce BMI inequalities in childhood and adolescence.

FUNDING

UK Economic and Social Research Council, Medical Research Council, and Academy of Medical Sciences/the Wellcome Trust.

Secular trends in height, weight and body mass index of primary school children in Turkey between 1993 and 2016

BACKGROUND

The aim of the study was to analyze the secular trends in height, weight and body mass index (BMI) of children in a Turkish primary school in a 23-year time interval.

METHODS

The height, weight and BMI of 1099 children between 7 and 15 years old were measured. Data were compared to those of children of the same ages from previous measurements carried out in 1993 (867 children) and in 2003 (1214 children) in the same school. The changes in weight, height and BMI were determined and analyzed statistically.

RESULTS

Weight increments between 7.7 and 16.2 kg/23 years and height increments between 1.1 and 8.3 cm/23 years were observed in boys. For girls, weight increments between 6.5 and 13.4 kg/23 years and height increments between 1.3 and 7.2 cm/23 years were indicated. Usually, there were significant height increments between 1993 and 2016 in both genders. However, there were no significant differences in height between 2003 and 2016 for all age groups. Furthermore, there were significant differences in BMI measurements in all age and gender groups between 1993 and 2016.

CONCLUSIONS

The secular ascending trend in height seems to stop between 2003 and 2016; however, increments in weight and mean BMI tend to continue in Turkish primary school children and adolescents.

Socioeconomic variation in height: analysis of National Child Measurement Programme data for England

OBJECTIVE

Short stature is associated with increased risk of ill health and mortality and can negatively impact on an individual's economic opportunity and psychological well-being. The aim of this study was to investigate the association between height and area-level deprivation by ethnic group in children in England.

DESIGN

Cross-sectional analysis of data gathered from the National Child Measurement Programme 2008/2009 to 2012/2013.

PARTICIPANTS/METHODS

Children (n=1 213 230) aged 4-5 and 10-11 years attending state-maintained primary schools in England. Mean height SD score (SDS) (based on the British 1990 growth reference) was calculated for children by Income Deprivation Affecting Children Index as a measure of area-level deprivation. Analyses were performed by sex and age group for white British, Asian and black ethnicities.

RESULTS

For white British children mean height decreased 0.2 SDS between the least and the most deprived quintile. For Asian children the relationship was weaker and varied between 0.08 and 0.18 SDS. For white British boys the magnitude of association was similar across age groups; for Asian boys the magnitude was higher in the age group of 10-11 years and in white British girls aged 10-11 years the association decreased. Height SDS was similar across all levels of deprivation for black children.

CONCLUSIONS

Social inequalities were shown in the height of children from white British and Asian ethnic groups. Further evaluation of height in black children is warranted. Action is needed to reduce inequalities in height by addressing the modifiable negative environmental factors that prevent healthy growth and development of children.

Trends in physical stature across socioeconomic groups of Chilean boys, 1880-1997

This paper studies the trends in height-by-age across socioeconomic groups of Chilean boys aged 5-18 born between 1880 and 1997, by performing a meta-analysis of 38 studies reporting height-by-age published since 1898. We estimate the trends using quantile regressions and by analyzing detailed height data from five selected studies. Both methods yield an average decennial increase in height of 1-1.1cm, and 0.9 and 1.2-1.3 cm for boys of upper and lower socioeconomic status (SES), respectively. SES differences in heights of 9-11 cm are observed up to the late 1940s. However, boys born after the 1930s exhibit substantial convergence in height between socioeconomic groups, driven by an increase in height of middle and lower SES boys of 1.5 and 1.4-2 cm per decade, respectively. As a result, SES differences in height decreased to 5 cm in 1990s. Since these changes occurred in a context of moderate economic growth and persistent income inequality, we argue that our findings are associated with the emergence and expansion of social policies in Chile since the 1940s, which delivered steady improvements in health, nutrition and living conditions.

Long-term changes of socioeconomic differences in height among young adult men in Southern Sweden, 1818-1968

The study explores the long-term trends in socioeconomic differences in height among young adult men. We linked information from conscript inspections to a longitudinal demographic database of five parishes in Southern Sweden. Detailed information on the occupation and landholding was used to investigate the differences in height. Even if there is indication of a reduction in the magnitude of the differences in height over time the reduction is neither dramatic nor uniform. The most systematic and consistent difference is that sons of fathers with white collar occupations were taller than others. They were 4cm taller than the sons of low-skilled manual workers in the first half of the 19th century, and almost 2cm taller in the mid-20th century. This difference is much smaller than those found between elite and destitute groups historically, in for example Britain, but comparable to that found in other studies on 19th century populations using information on family background. Most of the reduction in the socioeconomic differences in height was a result of reduced height penalty and premium for small disadvantaged and privileged groups. Changes in the distribution of income and the economic structure are plausible explanations for the changes in socioeconomic differences in height.

Socioeconomic differences in childhood length/height trajectories in a middle-income country: a cohort study

BACKGROUND

Socioeconomic disadvantage is associated with shorter adult stature. Few studies have examined socioeconomic differences in stature from birth to childhood and the mechanisms involved, particularly in middle-income former Soviet settings.

METHODS

The sample included 12,463 Belarusian children (73% of the original cohort) born in 1996-1997, with up to 14 stature measurements from birth to 7 years. Linear spline multi-level models with 3 knots at 3, 12 and 34 months were used to analyse birth length and growth velocity during four age-periods by parental educational achievement (up to secondary school, advanced secondary/partial university, completed university) and occupation (manual, non-manual).

RESULTS

Girls born to the most (versus least) educated mothers were 0.43 cm (95% confidence interval (CI): 0.28, 0.58) longer at birth; for boys, the corresponding difference was 0.30 cm (95% CI: 0.15, 0.46). Similarly, children of the most educated mothers grew faster from birth-3 months and 12-34 months (p-values for trend ≤ 0.08), such that, by age 7 years, girls with the most (versus least) educated mothers were 1.92 cm (95% CI: 1.47, 2.36) taller; after controlling for urban/rural and East/West area of residence, this difference remained at 1.86 cm (95% CI: 1.42, 2.31), but after additionally controlling for mid-parental height, attenuated to 1.10 cm (95% CI: 0.69, 1.52). Among boys, these differences were 1.95 cm (95% CI: 1.53, 2.37), 1.89 cm (95% CI: 1.47, 2.31) and 1.16 cm (95% CI: 0.77, 1.55), respectively. Additionally controlling for breastfeeding, maternal smoking and older siblings did not substantively alter these findings. There was no evidence that the association of maternal educational attainment with growth differed in girls compared to boys (p for interaction = 0.45). Results were similar for those born to the most (versus least) educated fathers, or who had a parent with a non-manual (versus manual) occupation.

CONCLUSIONS

In Belarus, a middle-income former Soviet country, socioeconomic differences in offspring growth commence in the pre-natal period and generate up to approximately 2 cm difference in height at age 7 years. These associations are partly explained by genetic or other factors influencing parental stature.

TRIAL REGISTRATION

Current Controlled Trials: NCT01352247 assigned 9 Sept 2005; ClinicalTrials.gov. Identifier: NCT01561612 received 20 Mar 2012.

Maternal education inequalities in height growth rates in early childhood: 2004 Pelotas birth cohort study

Socio-economic inequalities in attained height have been reported in many countries. The aim of this study was to explore the age at which maternal education inequalities in child height emerge among children from a middle-income country. Using data from the 2004 Pelotas cohort study from Brazil we modelled individual height growth trajectories in 2106 boys and 1947 girls from birth to 4 years using a linear spline mixed-effects model. We examined the associations of maternal education with birth length and trajectories of growth in length/height, and explored the effect of adjusting for a number of potential confounder or mediator factors. We showed linear and positive associations of maternal education with birth length and length/height growth rates at 0-3 months and 12-29/32 months with very little association at 3-12 months, particularly in boys. By age 4 years the mean height of boys was 101.06 cm (SE = 0.28) in the lowest and 104.20 cm (SE = 0.15) in the highest education category (mean difference 3.14 cm, SE = 0.32, P < 0.001). Among girls the mean height was 100.02 cm (SE = 0.27) and 103.03 cm (SE = 0.15) in the lowest and highest education categories, respectively (mean difference 3.01 cm, SE = 0.31, P < 0.001). For both boys and girls there was on average a 3-cm difference between the extreme education categories. Adjusting for maternal height reduced the observed birth length differences across maternal education categories, but differences in postnatal growth rates persisted. Our data demonstrate an increase in the absolute and relative inequality in height after birth; inequality increases from approximately 0.2 standard deviations of birth length to approximately 0.7 standard deviations of height at age 4, indicating that height inequality, which was already present at birth, widened through differential growth rates to age 2 years.

Social inequalities in height: persisting differences today depend upon height of the parents

Background

Substantial increases in height have occurred concurrently with economic development in most populations during the last century. In high-income countries, environmental exposures that can limit genetic growth potential appear to have lessened, and variation in height by socioeconomic position may have diminished. The objective of this study is to investigate inequalities in height in a cohort of children born in the early 1990s in England, and to evaluate which factors might explain any identified inequalities.

Methods and Findings

12,830 children from The Avon Longitudinal Study of Parents and Children (ALSPAC), a population based cohort from birth to about 11.5 years of age, were used in this analysis. Gender- and age-specific z-scores of height at different ages were used as outcome variables. Multilevel models were used to take into account the repeated measures of height and to analyze gender- and age-specific relative changes in height from birth to 11.5 years. Maternal education was the main exposure variable used to examine socioeconomic inequalities. The roles of parental and family characteristics in explaining any observed differences between maternal education and child height were investigated.

Children whose mothers had the highest education compared to those with none or a basic level of education, were 0.39 cm longer at birth (95% CI: 0.30 to 0.48). These differences persisted and at 11.5 years the height difference was 1.4 cm (95% CI: 1.07 to 1.74). Several other factors were related to offspring height, but few changed the relationship with maternal education. The one exception was mid-parental height, which fully accounted for the maternal educational differences in offspring height.

Conclusions

In a cohort of children born in the 1990s, mothers with higher education gave birth to taller boys and girls. Although height differences were small they persisted throughout childhood. Maternal and paternal height fully explained these differences.

Socioeconomic inequalities in height, leg length and trunk length among children aged 6.5 years and their parents from the Republic of Belarus: evidence from the Promotion of Breastfeeding Intervention Trial (PROBIT)

BACKGROUND

Lower socioeconomic position is associated with shorter stature, in particular shorter leg length, but the magnitude of these associations in non-Western countries has received little attention.

AIM

To examine socioeconomic differentials in height, leg and trunk length in 6.5 year olds from the Republic of Belarus and compare these to differentials in parental height.

METHODS

Multivariable linear regression was used to examine associations in a cohort of 13 889 children.

RESULTS

Children from non-manual households were 1.0 cm (95% confidence interval: 0.7-1.3 cm) taller than those from manual households. Mothers and fathers from non-manual backgrounds were 0.7 cm (0.5-0.8) and 1.8 cm (1.6-2.0) taller than those from manual backgrounds, respectively. Associations with higher parental educational attainment were similar. The magnitudes of the associations of socioeconomic position with leg length were similar to those with trunk length. Adjusting for mid-parental height and number of older siblings attenuated associations markedly.

CONCLUSIONS

In Belarus, similar socioeconomic differentials in height were observed in both children and their parents. Among children, height differentials were partly explained by mid-parental height and number of older siblings. Leg length was not a more sensitive indicator of childhood socioeconomic conditions than trunk length.

Intra- and intergenerational social mobility in relation to height, weight and body mass index in a British national cohort

Using a sample of 2090 father and son pairs, the extent of intra- and inter-generational social mobility (migration between social classes) was examined over a 42-year period in a British cohort in relation to height, weight and body mass index (BMI). The mean height difference between the highest and lowest social class decreased from about 4 cm in the fathers' generation to about 3 cm in the sons' generation, indicating a decline in heterogeneity in height between classes. For fathers downward intra-generational social mobility ranged between 11% and 18% while between 16% and 26% were upwardly mobile; for sons 15% were downwardly mobile and 21% upwardly mobile. On average downwardly mobile fathers were shorter by between 0.1 cm and 0.7 cm while upwardly mobile fathers were taller by, on average, 0.6 cm to 1.7 cm. For sons, the downwardly mobile were on average 0.7 cm shorter and the upwardly mobile 0.8 cm taller. For weight and BMI there were no consistent relationships with intra-generational mobility in either the fathers' or sons' generations. Inter-generationally, between 18% and 19% of sons were downwardly mobile and between 39% and 40% were upwardly mobile; the downwardly mobile were shorter by about 0.9 cm and the upwardly taller by between 0.6 cm and 1.2 cm. Sons with higher BMI were more likely to be inter-generationally downwardly mobile.

Patterns and correlates of adult height in Sri Lanka

The present study examines patterns and socioeconomic and demographic correlates of adult height among Sri Lankan adults. Data were available for height and socio-demographic factors from a nationally representative cross-sectional sample of 4477 subjects above 18 years. Recruitment was between 2005 and 2006. Mean age of all subjects was 46.1±15.1 years. Mean height of males and females were 163.6±6.9cm and 151.4±6.4cm respectively. Mean height showed a significant negative correlation with age (p<0.001, r=-0.207). Highest mean height in females 154.0±5.9cm and males 165.6±6.9cm were observed in those born after 1977. Rural females (151.4±6.2cm) were significantly taller than the urban (151.3±7.2cm). However, this was not observed in males. In multivariate analysis, year of birth, level of education and household income were significantly associated with height. Height demonstrated a significant negative correlation with systolic blood pressure (r=-0.032), presence of diabetes (r=-0.069), total cholesterol (r=-0.106), HDL cholesterol (r=-0.142) and LDL cholesterol (r=-0.104). Height was associated with household income and level of education in Sri Lanka and demonstrated a distinct increasing trend over successive generations.

Relationship between childhood short stature and academic achievement in adolescents and young adults--a longitudinal study

AIM

To determine if short stature at 14 or 21 years and patterns of 'catch-up' growth from 5 to 14 or 21 years are related to academic achievement in adolescents.

METHODS

The Mater University of Queensland Study of Pregnancy is a longitudinal study of 7223 singleton infants born between 1981 and 1984. Data were available for cross-sectional analyses of 3785 adolescents of whom 2149 were seen as young adults. Longitudinal patterns of growth were examined for 2936 subjects from 5 to 14 years and 1753 subjects from 5 to 21 years.

RESULTS

Adolescents or young adults with height <10th centile had a lower mean Wide Range Achievement Test (WRAT) score in adolescence and at 21 years than those of normal height (2.7 and 3.0 points, respectively) and increased odds of a WRAT score <85 (1.57 and 1.87, respectively) and learning difficulties (1.61 and 1.78, respectively). For growth patterns from 5 to 14 years, adolescents short at 5 years, irrespective of height at 14 years, had a lower mean WRAT score and increased odds of WRAT score <85 and learning difficulties. However, for growth patterns from 5 to 21 years, only the group short at both ages had increased learning difficulties.

CONCLUSIONS

Youth short at 14 years or at 21 years and those persistently short have an increased prevalence of academic difficulties. Catch-up growth by 21, although not 14 years, was associated with improved outcomes.

Nutritional composition of the diets of South Asian, black African-Caribbean and white European children in the United Kingdom: the Child Heart and Health Study in England (CHASE)

In the UK, South Asian adults have increased risks of CHD, type 2 diabetes and central obesity. Black African-Caribbeans, in contrast, have increased risks of type 2 diabetes and general obesity but lower CHD risk. There is growing evidence that these risk differences emerge in early life and that nutritional factors may be important. We have therefore examined the variations in nutritional composition of the diets of South Asian, black African-Caribbean and white European children, using 24 h recalls of dietary intake collected during a cross-sectional survey of cardiovascular health in eighty-five primary schools in London, Birmingham and Leicester. In all, 2209 children aged 9-10 years took part, including 558 of South Asian, 560 of black African-Caribbean and 543 of white European ethnicity. Compared with white Europeans, South Asian children reported higher mean total energy intake; their intakes of total fat, polyunsaturated fat and protein (both absolute and as proportions of total energy intake) were higher and their intakes of carbohydrate as a proportion of energy (particularly sugars), vitamin C and D, Ca and haem Fe were lower. These differences were especially marked for Bangladeshi children. Black African-Caribbean children had lower intakes of total and saturated fat (both absolute and as proportions of energy intake), NSP, vitamin D and Ca. The lower total and saturated fat intakes were particularly marked among black African children. Appreciable ethnic differences exist in the nutritional composition of children's diets, which may contribute to future differences in chronic disease risk.

Secular trends in social class differences of height, weight and BMI of boys from two schools in Lisbon, Portugal (1910-2000)

Data on the physical growth of children can provide useful information about the temporal changes in the economic conditions of the society in which they live and the extent of social inequalities within that society as well. Several studies have documented secular changes in the physical growth of children or of adult height, but seldom have the socioeconomic differences in secular trend been reported. The aim of this study is to examine differences in the secular trend of height, weight and BMI of 10-16-year-old boys enrolled in two schools of opposite socioeconomic makeup in Lisbon, Portugal, in the early and late 20th century. The samples from the upper-middle class come from the Colégio Militar, a military boarding school, and the lower-class samples come from the Casa Pia de Lisboa, a residential school for underprivileged boys. While boys from both schools show an approximate increase of 13.6cm in height, 13.5kg in weight and 2.4kg/m(2) in BMI, the Casa Pia students were shorter and lighter than their Colégio Militar counterparts throughout the 90-year period. Social class differences in mean height, weight and BMI tend to be greater in 1910 than in 2000, but results are statistically significant for height alone. When the two periods are taken together, Colégio Militar boys differ from their Casa Pia counterparts by approximately 6.4cm in height, 4.8kg in weight and 0.4kg/m(2) in BMI. Both samples show a considerable increase in height, weight and BMI but class differences in height, weight and BMI decreased slightly if at all, throughout the 90-year period. This suggests that socioeconomic disparities are persistent, having diminished only slightly since the early 20th century.

Secular trends in height and weight among children and adolescents of the Seychelles, 1956-2006

BACKGROUND

Height of individuals has long been considered as a significant index of nutrition and health of a population; still, there is little information regarding the trends of height and weight among developing or transitional countries. We assessed the secular trends in height and weight in children of the Seychelles, a rapidly developing island state in the Indian Ocean (African region).

METHODS

Height and weight were measured in all students of all schools in four selected school grades (kindergarten, 4th, 7th and 10th grades) for the periods 1998-9 (6391 children) and 2005-6 (8582 children). Data for 1956-7 was extracted from a previously published report.

RESULTS

At age 15.5 years, boys/girls were on average 10/13 cm taller and 15/9 kg heavier in 2005-6 than in 1956-7. Height increased in boys/girls by 1.62/0.93 cm/decade between 1956-7 and 1998-9 and by 1.14/1.82 cm/decade between 1998-9 and 2005-6. For weight, the linear increase in boys/girls was 1.38/1.10 kg/decade between 1956-7 and 1998-9 and 2.21/2.50 kg/decade between 1998-9 and 2005-6. Overall, the relative increase in weight between 1956-7 and 2005-6 was 5-fold higher than the relative increase in height.

CONCLUSION

Height and weight increased markedly over time in children aged <16 years in the Seychelles, consistent with large changes in socio-economic and nutritional indicators in the considered 50-year interval. The markedly steeper increase in weight than height over time is consistent with an epidemic of overweight and obesity.

An intergenerational and lifecourse study of health and mortality risk in parents of the 1958 birth cohort: (I) methods and tracing

OBJECTIVES

This paper describes the methods used to obtain information on mortality and cancer registrations for the parents of the British 1958 birth cohort, in order to create a dataset that can be used to examine intergenerational relationships on health and growth.

STUDY DESIGN

Intergenerational cohort study.

METHODS

The 1958 cohort includes all births occurring during 1 week in March 1958 in England, Scotland and Wales. For more than four decades of follow-up, information has been collected on cohort members, their parents and children. Information on the National Health Service (NHS) numbers of the parents was not available, but other details were collated for the Office for National Statistics to trace and flag the biological parents of the cohort members.

RESULTS

Tracing was successful in 90.2% of fathers (n = 14,334) and 94.9% of mothers (n = 15,076). The greatest success was achieved for parents in families where there was no indication for additional mother or father figures until the child was 16 years old (96.6% of the mothers traced, n = 14,274; 94.3% of the fathers traced, n = 13,256). Tracing rates were lower than average in unmarried mothers (59%) and for the small group who were separated, widowed or divorced in 1958 (81%); the rates were particularly poor for the corresponding fathers (24.4 and 54.7%, respectively). There were only small variations in tracing rates between different regions of Britain.

CONCLUSIONS

The tracing rates achieved were generally very high despite the lack of NHS number, especially where there was family stability throughout the childhood of cohort members. Parental status will need to be considered in future studies. With the high tracing rates achieved, the dataset provides an important resource with which to evaluate multigenerational associations with health and development in parents, their offspring and grandchildren.