Growth stunting in early life in relation to the onset of the childhood component of growth

Nutrition Justice: Uncovering Invisible Pathways to Malnutrition

We propose the use of the analytic frame of "nutrition justice" to reconcile the separate imperatives of Global Health for nutritional sufficiency for all, the requirement to eradicate childhood malnutrition, and the need for strategies to check the emerging pandemic of the double burden of malnutrition in the Global South. Malnutrition and its consequences of growth stunting are the result of disruption to the nutritional ecology of childhood from structural violence. This is mediated through loss of food security and perturbation to the cultural status of food, and on the prerequisites for nurture during infancy and early childhood. These socio-political factors obscure the role of biological adaptation to nutritional constraint on growth and hence the causal pathway to the double burden of malnutrition. In this paper we describe how the effects of historical and contemporary structural violence on the nutritional ecology of childhood are mediated using the examples of remote Aboriginal Australia and the Lao PDR. Both populations live by force of circumstance in a "metabolic ghetto" that has disrupted the prerequisites for parental nurturing through loss of food security and of traditional sources of transitional staple foods for weaning. Growth faltering and stunting of stature are markers of adaptation to nutritional constraint yet are also the first steps on the track to the double burden. We discuss the implications of these observations for strategies for global food sufficiency by mean of a thought-experiment of the effect of food and nutrient sufficiency for growth on future health and metabolic adaptation.

Estimating secular changes in longitudinal growth patterns underlying adult height with the QEPS model: the Grow Up Gothenburg cohorts

BACKGROUND

Over the past 150 years, humans have become taller, and puberty has begun earlier. It is unclear if these changes are continuing in Sweden, and how longitudinal growth patterns are involved. We aimed to evaluate the underlying changes in growth patterns from birth to adulthood by QEPS estimates in two Swedish cohorts born in 1974 and 1990.

METHODS

Growth characteristics of the longitudinal 1974 and 1990-birth cohorts (n = 4181) were compared using the QEPS model together with adult heights.

RESULTS

There was more rapid fetal/infancy growth in girls/boys born in 1990 compared to 1974, as shown by a faster Etimescale and they were heavier at birth. The laterborn were taller also in childhood as shown by a higher Q-function. Girls born in 1990 had earlier and more pronounced growth during puberty than girls born in 1974. Individuals in the 1990 cohort attained greater adult heights than those in the 1974 cohort; 6 mm taller for females and 10 mm for males.

CONCLUSION

A positive change in adult height was attributed to more growth during childhood in both sexes and during puberty for girls. The QEPS model proved to be effective detecting small changes of growth patterns, between two longitudinal growth cohorts born only 16 years apart.

A Prospective Longitudinal Cohort to Investigate the Effects of Early Life Giardiasis on Growth and All Cause Diarrhea

BACKGROUND

Growth stunting in children under 2 years of age in low-income countries is common. Giardia is a ubiquitous pathogen in this age group but studies investigating Giardia's effect on both growth and diarrhea have produced conflicting results.

METHODS

We conducted a prospective longitudinal birth cohort study in Dhaka, Bangladesh, with monthly Giardia and continuous diarrheal surveillance.

RESULTS

629 children were enrolled within the first 72 hours of life, and 445 completed 2 years of the study. 12% of children were stunted at birth with 57% stunted by 2 years. 7% of children had a Giardia positive surveillance stool in the first 6 months of life, whereas 74% had a positive stool by 2 years. The median time to first Giardia positive surveillance stool was 17 months. Presence of Giardia in a monthly surveillance stool within the first 6 months of life decreased length-for-age Z score at 2 years by 0.4 (95% confidence interval, -.80 to -.001; P value .05) whereas total number of Giardia positive months over the 2-year period of observation did not. Neither variable was associated with weight-for-age Z score at 2 years. In our model to examine predictors of diarrhea only exclusive breastfeeding was significantly associated with decreased diarrhea (P value <.001). Concomitant giardiasis was neither a risk factor nor protective.

CONCLUSIONS

Early life Giardia was a risk factor for stunting at age 2 but not poor weight gain. Presence of Giardia neither increased nor decreased odds of acute all cause diarrhea.

Effect of complementary feeding with lipid-based nutrient supplements and corn-soy blend on the incidence of stunting and linear growth among 6- to 18-month-old infants and children in rural Malawi

Low nutritional value of complementary foods is associated with high incidence of childhood growth stunting in low-income countries. This study was done to test a hypothesis that dietary complementation with lipid-based nutrient supplements (LNS) promotes linear growth and reduces the incidence of severe stunting among at-risk infants. A total of 840 6-month-old healthy infants in rural Malawi were enrolled to a randomised assessor-blinded trial. The participants received 12-month supplementation with nothing, milk-LNS, soy-LNS, or corn-soy blend (CSB). Supplements provided micronutrients and approximately 280 kcal energy per day. Outcomes were incidence of severe and very severe stunting [length-for-age z-score, (LAZ) < -3.00 and <-3.50, respectively], and change in LAZ. The incidence of severe stunting was 11.8%, 8.2%, 9.1% and 15.5% (P = 0.098) and that of very severe stunting 7.4%, 2.9%, 8.0% and 6.4% (P = 0.138) in control, milk-LNS, soy-LNS and CSB groups, respectively. Between 9 and 12 months of age, the mean change in LAZ was -0.15, -0.02, -0.12 and -0.18 (P = 0.045) for control, milk-LNS, soy-LNS and CSB groups, respectively. There was no significant between-group difference in linear growth during other age-intervals. Although participants who received milk-LNS had the lowest incidence of severe and very severe stunting, the differences between the groups were smaller than expected. Thus, the results do not provide conclusive evidence on a causal association between the LNS supplementation and the lower incidence of stunting. Exploratory analyses suggest that provision of milk-LNS, but not soy-LNS promotes linear growth among at-risk infants mainly between 9 and 12 months of age.

Impact of infancy duration on adult size in 22 subsistence-based societies

AIM

Humans evolved to withstand harsh environments by adaptively decreasing their body size. Thus, adaptation to a hostile environment defers the infancy-childhood transition age (ICT), culminating in short stature. In natural-fertility human societies, this transition is associated with weaning from breastfeeding and the mother's new pregnancy. We therefore used the interbirth interval (IBI) as a surrogate for the ICT.

METHODS

We hypothesized that long IBI will be associated with smaller body size. The sample used is 22 subsistence-based societies of foragers, horticulturalists and pastorals from Africa, South America, Australia and Southeast Asia.

RESULTS

The IBI correlated negatively with the average adult bodyweight but not height. After correction for 'pubertal spurt takeoff' and 'weight at age 5', the IBI explains 81% of 'average adult weight' variability.

CONCLUSIONS

This inter-population study confirms that body weight is adaptively smaller in hostile environments and suggests that the selected trait for this adaptation is the ICT age.

Evolutionary perspective in child growth

Hereditary, environmental, and stochastic factors determine a child's growth in his unique environment, but their relative contribution to the phenotypic outcome and the extent of stochastic programming that is required to alter human phenotypes is not known because few data are available. This is an attempt to use evolutionary life-history theory in understanding child growth in a broad evolutionary perspective, using the data and theory of evolutionary predictive adaptive growth-related strategies. Transitions from one life-history phase to the next have inherent adaptive plasticity in their timing. Humans evolved to withstand energy crises by decreasing their body size, and evolutionary short-term adaptations to energy crises utilize a plasticity that modifies the timing of transition from infancy into childhood, culminating in short stature in times of energy crisis. Transition to juvenility is part of a strategy of conversion from a period of total dependence on the family and tribe for provision and security to self-supply, and a degree of adaptive plasticity is provided and determines body composition. Transition to adolescence entails plasticity in adapting to energy resources, other environmental cues, and the social needs of the maturing adolescent to determine life-span and the period of fecundity and fertility. Fundamental questions are raised by a life-history approach to the unique growth pattern of each child in his given genetic background and current environment.

Child health, developmental plasticity, and epigenetic programming

Plasticity in developmental programming has evolved in order to provide the best chances of survival and reproductive success to the organism under changing environments. Environmental conditions that are experienced in early life can profoundly influence human biology and long-term health. Developmental origins of health and disease and life-history transitions are purported to use placental, nutritional, and endocrine cues for setting long-term biological, mental, and behavioral strategies in response to local ecological and/or social conditions. The window of developmental plasticity extends from preconception to early childhood and involves epigenetic responses to environmental changes, which exert their effects during life-history phase transitions. These epigenetic responses influence development, cell- and tissue-specific gene expression, and sexual dimorphism, and, in exceptional cases, could be transmitted transgenerationally. Translational epigenetic research in child health is a reiterative process that ranges from research in the basic sciences, preclinical research, and pediatric clinical research. Identifying the epigenetic consequences of fetal programming creates potential applications in clinical practice: the development of epigenetic biomarkers for early diagnosis of disease, the ability to identify susceptible individuals at risk for adult diseases, and the development of novel preventive and curative measures that are based on diet and/or novel epigenetic drugs.

Developmental plasticity in child growth and maturation

The ability of a given genotype to produce different phenotypes in response to different environments is termed "plasticity," and is part of the organism's "adaptability" to environmental cues. The expressions of suites of genes, particularly during development or life history transitions, probably underlie the fundamental plasticity of an organism. Plasticity in developmental programming has evolved in order to provide the best chances of survival and reproductive success to organisms under changing environments. Environmental conditions that are experienced in early life can profoundly influence human biology, child growth and maturation, and long-term health and longevity. Developmental origins of health and disease and life history transitions are purported to use placental, nutritional, and endocrine cues for setting long-term biological, mental, and behavioral strategies for child growth and maturation in response to local ecological and/or social conditions. The window of developmental plasticity extends from conception to early childhood, and even beyond to the transition from juvenility to adolescence, and could be transmitted transgenerationally. It involves epigenetic responses to environmental changes, which exert their effects during life history phase transitions.

Evo-devo of infantile and childhood growth

Human size is a tradeoff between the evolutionary advantages and disadvantages of being small or big. We now propose that adult size is determined to an important extent during transition from infancy to childhood. This transition is marked by a growth spurt. A delay in the transition has a lifelong impact on stature and is responsible for 44% of children with short stature in developed countries and many more in developing countries. Here, we present the data and theory of an evolutionary adaptive strategy of plasticity in the timing of transition from infancy into childhood to match the prevailing energy supply. We propose that humans have evolved to withstand energy crises by decreasing their body size, and that evolutionary short-term adaptations to energy crises trigger a predictive adaptive response that modify the transition into childhood, culminating in short stature.

Growth velocity standards from longitudinally measured infants of age 0-2 years born in Shiraz, southern Iran

This paper presents growth velocity data for a cohort of 317 infants (164 girls and 153 boys) born in Shiraz, southern Iran, in 1996 and followed longitudinally for 2 years. The growth velocity of five anthropometric measurements (height, weight, arm, head, and chest circumferences) declined rapidly from 2 weeks to 7 months of age and less steeply thereafter for both sexes. Growth velocities for boys were higher than girls in the first months but did not differ significantly later on. However, growth velocity centiles for girls lie below those for boys throughout the age range studied. Weight velocities in the Iranian infants were significantly lower than for corresponding infants in the U.K., the Middle East, and Africa, but height velocities were generally higher.

Longitudinal growth during infancy and childhood in children from shanghai: predictors and consequences of the age at onset of the childhood phase of growth

The age at onset of the childhood phase of growth, normally occurring between 6 and 12 mo, is recognized to be an important time during postnatal human development. The aims of this present work were to identify predictors for the age at onset of the childhood phase of growth. Furthermore, this work aimed to examine the consequences that this timing would have on the subsequent heights of 1720 Shanghai children. The mean age of the infants at onset of the childhood phase of growth was 11.2 mo in boys and 10.7 mo in girls. Compared with their Swedish counterparts, these means occurred 1.3 mo later in boys and 1.4 mo later in girls. Both age at onset of the childhood phase of growth and length at 6 mo of age significantly (p < 0.05) contributed to the attained height from 12 mo of age onward; 1-mo delay in the onset of the childhood phase of growth reduced height at 5 y of age by 0.4 cm in boys and 0.5 cm in girls. The age at onset of the childhood phase of growth was negatively associated (p < 0.001) with mid-parental height, although positively related (p < 0.001) to height at 6 mo of age. There was a distinct body mass index pattern of Chinese children between birth and 6 y of age in comparison with white values. There was a sharp increase in body mass index in Shanghainese during their first 6 mo of life, followed by a gradual decline up to 24 mo. In conclusion, the age at childhood onset is equally important when studying children from Shanghai as it is with their Swedish counterparts.

Critical growth phases for adult shortness in Hong Kong Chinese

OBJECTIVES

This study was designed to explore whether the influence of subnormal growth in fetal, infancy, childhood and pubertal phases on adult short stature was the same when comparing privileged and underprivileged populations.

METHODS

Data came from two longitudinal growth studies: 1) Hong Kong Chinese children who were born in 1967 (n = 132), and 2) the comparatively more privileged Swedish children who were born in 1973-1975 (n = 2,850).

RESULTS

68% of Hong Kong Chinese children had two or more growth phases subnormal, much higher than the 12.4% for Swedish children. 42.4% of Hong Kong Chinese were short at final height, much higher than the 2.2% for Swedish children. Subnormal growth in any growth phase was associated with an increased risk of adult short stature in both series (p<0.01). After adjustment for mid-parental height, the place of residence (Hong Kong/Sweden) was not significant for adult shortness (p>0.05) in the pooled data.

CONCLUSIONS

The impact of subnormal growth in any phase on adult shortness is similar in privileged and underprivileged populations. The much higher prevalence of subnormal growth and consequently adult short stature in developing countries is likely mainly attributable to adverse extrinsic or environmental influences.

Long-term consequences of early linear growth retardation (stunting) in Swedish children

Linear growth retardation (stunting) is prevalent (10-80%) in developing countries. It takes place between 6 and 18 mo of age and can be characterized by the delayed onset of the childhood phase of growth. The objective of this work was to study the existence of stunting in early life and, when present, its lifelong effects on final height in a normal healthy population in a developed country. A total of 2432 children with longitudinal height data from birth to adulthood were analyzed. The series represents a normal healthy population-based sample of full-term children born around 1974 in Göteborg, Sweden. We found the incidence of stunting to be about 10% as indicated by delayed onset of the childhood phase of growth (>12 mo of age): 14% in boys and 8% in girls. In a multiple linear regression model, final height was described by length at 6 mo of age, age at onset of the childhood phase of growth, and age at peak height velocity during puberty. All three measures contributed significantly (p < 0.05) to final height with a total R2 of 0.33. A final height difference of 5.0 cm could be explained by abnormal onset of the childhood phase of growth in this normal population. The timing of the childhood onset of growth did not correlate with the timing of puberty. For the first time, we can conclude that stunting in early life is not only a problem in developing countries. Its importance on final height achieved is clearly shown, even after controlling for the timing of puberty.

Fetal size to final height in Hong Kong Chinese children

OBJECTIVES

It has been known that size at birth is important for postnatal growth and final height. However, there are few data in the literature on the difference in height growth patterns from fetal size to final height between less privileged and more privileged populations. The aim of this study was to describe the important features in height growth from birth to maturity in an underprivileged Hong Kong Chinese cohort in comparison to a more privileged Swedish cohort.

METHODS

The longitudinal height growth data from birth to maturity in full-term healthy Hong Kong Chinese children (n=132) who were born in 1967 were analyzed, and compared with those for Swedish children who were born in 1973-75 (n=3650).

RESULTS

Children with longer birth length achieved taller adult stature with respect to their target height. The mean final height retained the same order as that of the mean length at birth for various birth length groups. All children in the Hong Kong Chinese series showed catch-down height growth during the first 2 years of life, in contrast to the catch-up in smaller babies and catch-down in larger babies for the Swedish series. The growth deficit for the Hong Kong Chinese was -0.9 SDS at birth, -1.8 SDS at 2.0 years of age, -2.1 SDS at 8 years of age, and -1.7 SDS at final height.

CONCLUSIONS

Fetal size is important for postnatal growth and attained final height with respect to a child's familial genetic potential in stature, not only for privileged populations, but also for underprivileged populations. However, children in underprivileged populations experience a persistent increasing growth deficit during infancy and childhood. Special attention should be given to monitor their growth status in early years and to institute appropriate intervention programs.