Predictors of growth velocity in early infancy in a resource-poor setting

Auxology of small samples: A method to describe child growth when restrictions prevent surveys

Background

Child growth in populations is commonly characterised by cross-sectional surveys. These require data collection from large samples of individuals across age ranges spanning 1–20 years. Such surveys are expensive and impossible in restrictive situations, such as, e.g. the COVID pandemic or limited size of isolated communities. A method allowing description of child growth based on small samples is needed.

Methods

Small samples of data (N~50) for boys and girls 6–20 years old from different socio-economic situations in Africa and Europe were randomly extracted from surveys of thousands of children. Data included arm circumference, hip width, grip strength, height and weight. Polynomial regressions of these measurements on age were explored.

Findings

Polynomial curves based on small samples correlated well (r = 0.97 to 1.00) with results of surveys of thousands of children from same communities and correctly reflected sexual dimorphism and socio-economic differences.

Conclusions

Fitting of curvilinear regressions to small data samples allows expeditious assessment of child growth in a number of characteristics when situations change rapidly, resources are limited and access to children is restricted.

The Consecutive 3-month Length Increment to Predict Early Linear Growth Failure

AIM: This study aimed to assess the consecutive 3-month length increment thresholds, by the first 6 months, to predict stunted at the age of 6 months. METHODS: We analyzed data from the Bogor Longitudinal Study on Child Growth and Development in West Java, Indonesia. A total of 635 free of stunting at birth children were analyzed in this study. Early linear growth faltering, as the dependent variable, was the stunted at 6 months of age. The four thresholds of the consecutive 3-month length increment were considered in predicting stunted at the age of 6 months. The thresholds were a consecutive 3-month length increment below 25th percentile, 15th percentile, and 5th percentile of the WHO Child Growth Velocity Standard. The 4th threshold was generated from the Bogor Longitudinal Study sample and determined using receiver operating characteristic analysis. The sensitivity, specificity, PPV, and NPV of the thresholds were calculated. RESULTS: Among the thresholds, the 25th percentile of the WHO Child Growth Velocity Standard generates the highest sensitivity. The ability of the 25th percentile threshold to correctly identify children who had stunting at 6 months of age is 56.7%. However, the children whose experience a consecutive 3-month length increment below 15th percentile had highest risk to become stunted at the age of 6 months, adjusted by sex, birthweight, and birth length. CONCLUSION: A consecutive 3-month length increment could be beneficial as a tool in identifying infants at high risk of early linear growth failure in stunted prevalent population.

Socioeconomic inequalities in children's weight, height and BMI trajectories in Norway

Studies exploring when social inequalities in body mass index (BMI) and its composites emerge and how these evolve with age are limited. Thus, this study explored parental income and education related inequalities in children's weight, height, weight velocity and body mass index among Norwegian children from 1 month to 8 years. The study population included 59,927 family/children pairs participating in the Norwegian Mother, Father, and Child Cohort Study. Growth was modelled using the Jenss-Bayley model and linear mixed effects analyses were conducted. Maternal and paternal educational differences in children's weight and BMI trajectories emerged during infancy, continuing to age 8 years. Parental income-related inequalities in children's weight were observed from the age of 1 month to 4 years for maternal and up to 1 year for paternal income-related differences but then disappeared. Parental income-related inequalities in child's BMI were observed from 18 months to 8 years for maternal income, and from 9 months to 8 years for paternal income-related differences. These results suggest that social inequalities in children's BMI present early in infancy and continue to 8 years of age. The inequalities sometimes differed by indicator of socioeconomic position used. Interventions to combat these inequalities early in life are, thus needed.

Comparison of growth models to describe growth from birth to 6 years in a Beninese cohort of children with repeated measurements

OBJECTIVE

To select a growth model that best describes individual growth trajectories of children and to present some growth characteristics of this population.

SETTINGS

Participants were selected from a prospective cohort conducted in three health centres (Allada, Sekou and Attogon) in a semirural region of Benin, sub-Saharan Africa.

PARTICIPANTS

Children aged 0 to 6 years were recruited in a cohort study with at least two valid height and weight measurements included (n=961).

PRIMARY AND SECONDARY OUTCOME MEASURES

This study compared the goodness-of-fit of three structural growth models (Jenss-Bayley, Reed and a newly adapted version of the Gompertz growth model) on longitudinal weight and height growth data of boys and girls. The goodness-of-fit of the models was assessed using residual distribution over age and compared with the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The best-fitting model allowed estimating mean weight and height growth trajectories, individual growth and growth velocities. Underweight, stunting and wasting were also estimated at age 6 years.

RESULTS

The three models were able to fit well both weight and height data. The Jenss-Bayley model presented the best fit for weight and height, both in boys and girls. Mean height growth trajectories were identical in shape and direction for boys and girls while the mean weight growth curve of girls fell slightly below the curve of boys after neonatal life. Finally, 35%, 27.7% and 8% of boys; and 34%, 38.4% and 4% of girls were estimated to be underweight, wasted and stunted at age 6 years, respectively.

CONCLUSION

The growth parameters of the best-fitting Jenss-Bayley model can be used to describe growth trajectories and study their determinants.

Criteria for undernutrition screening in hospitalised infants under 6 months: a diagnostic accuracy study in a resource-poor setting

PURPOSE

We aimed to describe the prevalence of undernutrition in hospitalised infants aged under 6 months and test the utility of simple index measures to detect undernutrition.

DESIGN

Diagnostic accuracy study: weight, length, mid-upper arm circumference (MUAC), triceps and subscapular skinfolds were measured in infants aged 2 weeks to 6 months admitted to a Teaching Hospital in Enugu, Nigeria. Index criteria : low (<-2SD) weight-for-age Z-scores (WAZ), weight-for-length Z-scores (WLZ); MUAC <11 cm. Reference definition: weight faltering (conditional weight gain below fifth percentile for healthy Nigerian infants) or sum of skinfolds (SSF) <10 mm.

RESULTS

Of 125 hospitalised infants, only 5% (6) were admitted specifically for undernutrition, but low SSF were found in 33% (41) and, 24% (25) with known birth weight had weight faltering, giving an undernutrition prevalence of 36%. Low WAZ was the most discriminating predictor of undernutrition (sensitivity 69%, positive predictive value 86%, likelihood ratio 5.5; area under receiver operator curves 0.90) followed by MUAC (73%, 73%, 4.9; 0.86), while WLZ performed least well (49%, 67%, 2.9; 0.84). Where both MUAC and WAZ were low, there was sensitivity 90%, positive predictive value 82% and likelihood ratio 8.7.

CONCLUSIONS

Infants aged under 6 months admitted to hospital in Nigeria had a high prevalence of undernutrition. In young, high-risk population, a low WAZ alone was a valuable screening criterion, while combining weight with MUAC gave even higher discrimination. Measurement of length to calculate WLZ was a less useful predictor in this population.

Neonatal azithromycin administration to prevent infant mortality: study protocol for a randomised controlled trial

INTRODUCTION

Biannual mass azithromycin distribution to children aged 1-59 months has been shown to reduce all-cause mortality. Children under 28 days of age were not treated in studies evaluating mass azithromycin distribution for child mortality due to concerns related to infantile hypertrophic pyloric stenosis (IHPS). Here, we report the design of a randomised controlled trial to evaluate the efficacy and safety of administration of a single dose of oral azithromycin during the neonatal period.

METHODS AND ANALYSIS

The Nouveaux-nés et Azithromycine: une Innovation dans le Traitement des Enfants (NAITRE) study is a double-masked randomised placebo-controlled trial designed to evaluate the efficacy of a single dose of azithromycin (20 mg/kg) for the prevention of child mortality. Newborns (n=21 712) aged 8-27 days weighing at least 2500 g are 1:1 randomised to a single, directly observed, oral dose of azithromycin or matching placebo. Participants are followed weekly for 3 weeks after treatment to screen for adverse events, including IHPS. The primary outcome is all-cause mortality at the 6-month study visit.

ETHICS AND DISSEMINATION

This study was approved by the Institutional Review Boards at the University of California, San Francisco in San Francisco, USA (Protocol #18-25027) and the Comité National d'Ethique pour la Recherche in Ouagadougou, Burkina Faso (Protocol #2018-10-123). The findings of this trial will be presented at local, regional and international meetings and published in open access peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03682653; Pre-results.

Factors associated with recovery from stunting among under-five children in two Nairobi informal settlements

Childhood stunting is a public health concern in many low-and-middle income countries, as it is associated with both short-term and long-term negative effects on child cognitive development, physical health, and schooling outcomes. There is paucity of studies on recovery from stunting among under five children in these countries. Most studies focused on the recovery much later in adolescence. We used longitudinal data from two Nairobi urban settlements to determine the incidence of recovery from stunting and understand the factors associated with post-stunting linear growth among under-five children. A total of 1,816 children were recruited between birth and 23 months and were followed-up until they reached five years. We first looked at the time to recover from stunting using event history analysis and Cox regression. Second, we used height-for-age z-score slope modelling to estimate the change in linear growth among children who were stunted. Finally, we fitted a linear regression model of the variation in HAZ on a second degree fractional polynomials in child’s age to identify the factors associated with post-stunting linear growth. The principal findings are: i) the incidence of recovery from stunting was 45% among stunted under-five children in the two settlements; ii) timely child immunization, age at stunting, mother’s parity and household socioeconomic status are important factors associated with time to recover from stunting within the first five years of life; and iii) child illness status and age at first stunting, mother’s parity and age have a strong influence on child post-stunting linear growth. Access to child health services and increased awareness among health professionals and child caregivers, would be critical in improving child growth outcomes in the study settings. Additionally, specific maternal and reproductive health interventions targeting young mothers in the slums may be needed to reduce adolescent and young mother’s vulnerability and improve their child health outcomes.

Mapping the content of mothers' knowledge, attitude and practice towards universal newborn hearing screening for development of a KAP survey tool

Understanding mother’s knowledge, attitude and practice (KAP) of permanent childhood hearing impairment (PCHI) is essential for the success of universal newborn hearing screening (UNHS) as poor compliance and follow-up remains a global challenge. To determine content area for a questionnaire that measures PCHI-related KAP in rural mothers, we trained moderators who interviewed 145 pregnant women (17 groups) from 5 ante-natal clinics. Interviews were recorded, transcribed, summarised and analysed using thematic framework analysis. Four knowledge themes were identified: 1) PCHI was perceived as the malfunction of hearing leading to disability; 2) a poorly-responsive/communicative child may have PCHI; 3) lifestyle, hereditary and environmental factors are significant causes of PCHI; 4) medical management of PCHI was doubted, with some advocating birth and ancestral rituals. Two themes were identified for attitude: 1) beliefs that PCHI was emotionalised due to the negative lifelong impact on the child and family; 2) UNHS processes were favourable though some preferred other belief systems. Three themes were identified for practice: 1) doctors were the first choice followed by traditional healers; 2) willingness to continue follow-up although challenges exist; 3) minimal family support during consultation. The contextualised KAP of women regarding UNHS processes and PCHI provided content area for the design of a KAP tool.

Growth curves and their associated weight and height factors in children from birth to 4 years old in West Azerbaijan Province, northwest Iran

BACKGROUND

Growth trajectory standards are important components that need to be monitored for suitable child growth. This study examined longitudinal data to identify the factors affecting growth trajectory standards of height and weight for infants.

METHODS

This study included 566 neonates (286 boys and 280 girls) born in West Azerbaijan Province, northwest Iran, who were followed from birth to 4 years of age. The subjects' weight and height were recorded at birth, 1, 2, 4, 6, 9 months and 1, 1.5, 2, 3, and 4 years of age. In this study, the Lambda-Mu-Sigma (LMS) method was used to construct the growth curves for each measure. The linear mixed model was employed to determine the factors affecting the growth trajectory.

RESULTS

The study demonstrates that the place of birth, duration of breastfeeding, and infants' gender had a significant effect on the growth trajectory. Nonetheless, other variables did not have any significant effect on growth. Growth curves for significant factors of weight and height (5th, 50th, 95th percentiles) were obtained. There was a rapid increase in the growth curve from birth to 2 years of age, which then remained relatively constant up to 4 years of age.

DISCUSSION

This paper provides the first local growth trajectory standards of height and weight for infants by analyzing longitudinal measurements in West Azerbaijan province. This study determined the factors affecting the growth trend in both indices. It seems that there was a significant difference in the growth trajectories of infants in subgroups of the effective factor.

Weight-Gain Velocity in Newborn Infants Managed with the Kangaroo Method and Associated Variables

Objectives The Kangaroo method helps promote maternal breastfeeding and adequate growth of low birthweight preterm infants. The objective of this study was to analyze the association between weight-gain velocity during use of the Kangaroo method and maternal and infant variables. Methods A nested cross-sectional study in a cohort of newborn infants managed using the Kangaroo method was carried out at a reference center for the method in Brazil. Data on low birthweight and preterm infants managed using the Kangaroo Method (n = 78) and on their respective mothers (n = 70) was collected between January and July 2014. Maternal and infant variables were associated and correlated with weight-gain velocity (g/kg/day) at each phase of the method (p < 0.05). Results Mean weight-gain velocity increased from 0.12 ± 11.11 g/kg/day in the first phase to 13.47 ± 4.84 g/kg/day in the third phase (p < 0.001), and percentage of adequate weight increased at phase 3 (p < 0.001). Birthweight was inversely correlated with weight-gain velocity at phases 1 and 2 of the Kangaroo method. Birthweight of under 1500 g was associated with a lower likelihood of inadequate weight-gain velocity of the newborn at phase 1 (OR = 0.1; 95 % CI 0.01-0.78; p = 0.012). In phase 3, maternal age was directly correlated with weight-gain velocity. Conclusions Weight-gain velocity was associated with maternal (age) and infant (gestational age at birth, birthweight, weight for gestational age at birth, length of hospital stay and five-minute Apgar score) variables. Knowledge of the factors influencing weight-gain velocity and its behavior at each phase of the method can help guide conduct toward potentializing factors that promote adequate weight-gain.

Low birth weight, very low birth weight and extremely low birth weight in African children aged between 0 and 5 years old: a systematic review

Low birth weight (LBW<2500), very low birth weight (VLBW<1500), extremely low birth weight (ELBW<1500) infants are at high risk for growth failure that result in delayed development. Africa is a continent that presents high rates of children born with LBW, VLBW and ELBW particularly sub-Saharan Africa. To review the existing literature that explores the repercussions of LBW, VLBW and ELBW on growth, neurodevelopmental outcome and mortality in African children aged 0–5 years old. A systematic review of peer-reviewed articles using Academic Search Complete in the following databases: PubMed, Scopus and Scholar Google. Quantitatives studies that investigated the association between LBW, VLBW, ELBW with growth, neurodevelopmental outcome and mortality, published between 2008 and 2015 were included. African studies with humans were eligible for inclusion. From the total of 2205 articles, 12 articles were identified as relevant and were subsequently reviewed in full version. Significant associations were found between LBW, VLBW and ELBW with growth, neurodevelopmental outcome and mortality. Surviving VLBW and ELBW showed increased risk of death, growth retardation and delayed neurodevelopment. Post-neonatal interventions need to be carried out in order to minimize the short-term effects of VLBW and ELBW.

Longitudinal standards for growth velocity of infants from birth to 4 years born in West Azerbaijan Province of northwest Iran

OBJECTIVES:

Growth velocity is an important factor to monitor for appropriate child growth. This study presents the growth velocity of infants based on length, weight, and head circumference.

METHODS:

The subjects of this study were 308 neonates (160 boys and 148 girls) born in West Azerbaijan Province of northwestern Iran who were followed from birth for 4 years. The weights and lengths of the subjects were recorded at birth, 1, 2, 4, 6, and 9 months, and 1, 1.5, 2, 3, and 4 years of age, while the head circumferences were measured just up to 1.5 years of age. In this study, the Lambda-Mu-Sigma (LMS) method using LMS Chartmaker Pro (Institute of Child Health, London, UK) was utilized to obtain growth velocity percentiles.

RESULTS:

After obtaining growth velocity charts for weight, length, and head circumference (5th, 50th, and 95th percentiles), the researchers could deduce that there was a sharp decrease in the velocity growth charts from birth to 2 years of age but these charts remained relatively stable up to 4 years for both sexes. Growth velocities for the length and weight of boys in the present sample are slightly but not significantly greater than those in girls through the first months of infancy and there was no significant difference between girls and boys up to 4 years.

CONCLUSIONS:

This paper provided the first local growth velocity standards of length, weight, and head circumference for infants by analyzing longitudinal measurements produced for West Azerbaijan Province, which should be updated periodically. It seems that there has been a significant difference between the growth velocity of infants in northwestern Iran and southern Iran within the past few years.

HIV infection, viral load, low birth weight, and nevirapine are independent influences on growth velocity in HIV-exposed South African infants

Data from a prospective multisite cohort study were used to examine the effect of HIV exposure, untreated HIV infection, and single-dose nevirapine on infant growth velocity. The 2009 WHO growth velocity standards constitute a new tool for this type of investigation and are in need of functional validation. In period 1 (3-24 wk), 65 HIV-infected, 502 HIV-exposed uninfected (HEU), and 216 HIV-unexposed infants were included. In period 2 (25-36 wk), 31 infants moved from the HEU group to the HIV-infected group. We compared weight velocity Z-scores (WVZ) and length velocity Z-scores (LVZ) by HIV group and assessed their independent influences. In period 1, mean WVZ (95% CI) was significantly (P < 0.001) lower in infected [-0.87 (-1.77, 0.04)] than HEU [0.81 (0.67, 0.94)] and unexposed [0.55 (0.33, 0.78)] infants. LVZ showed similar associations. In both periods, sick infants and those exposed to higher maternal viral loads had lower WVZ. Higher mean LVZ was associated with low birth weight. Infants that had received nevirapine had higher LVZ. In conclusion, HIV infection and not exposure was associated with low WVZ and LVZ in period 1. Eliminating infant HIV infection is a critical component in averting HIV-related poor growth patterns in infants in the first 6 mo of life.

Newborn length predicts early infant linear growth retardation and disproportionately high weight gain in a low-income population

BACKGROUND

Stunting is prevalent by the age of 6 months in the indigenous population of the Western Highlands of Guatemala.

AIM

The objective of this study was to determine the time course and predictors of linear growth failure and weight-for-age in early infancy.

STUDY DESIGN AND SUBJECTS

One hundred and forty eight term newborns had measurements of length and weight in their homes, repeated at 3 and 6 months. Maternal measurements were also obtained.

RESULTS

Mean ± SD length-for-age Z-score (LAZ) declined from newborn -1.0 ± 1.01 to -2.20 ± 1.05 and -2.26 ± 1.01 at 3 and 6 months respectively. Stunting rates for newborn, 3 and 6 months were 47%, 53% and 56% respectively. A multiple regression model (R(2) = 0.64) demonstrated that the major predictor of LAZ at 3 months was newborn LAZ with the other predictors being newborn weight-for-age Z-score (WAZ), gender and maternal education∗maternal age interaction. Because WAZ remained essentially constant and LAZ declined during the same period, weight-for-length Z-score (WLZ) increased from -0.44 to +1.28 from birth to 3 months. The more severe the linear growth failure, the greater WAZ was in proportion to the LAZ.

CONCLUSION

The primary conclusion is that impaired fetal linear growth is the major predictor of early infant linear growth failure indicating that prevention needs to start with maternal interventions.

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.

Pattern and characteristics of growth faltering in early infancy in an urban sub-Saharan African setting

OBJECTIVE

To determine the pattern of and factors associated with changes in nutritional status in early infancy in a resource-poor setting.

METHODS

A cohort study in Lagos, Nigeria, in which the nutritional status at birth was compared with status at the first postnatal check-up routinely scheduled for 6-8 weeks based on the World Health Organization's multicenter growth reference and the Centers for Disease Control and Prevention 2000 growth charts. Factors associated with improved, worsened or steady nutritional status at follow-up based on z-scores for weight-for-age, length-for-age and weight-for-length were determined with multinomial regression analysis.

RESULTS

The mean length-for-age and weight-for-length based on the Centers for Disease Control and Prevention for the 445 full-term singletons studied were higher than the corresponding World Health Organization's multicenter growth reference values at birth and at follow-up, while mean weight-for-age was lower at birth but higher subsequently. Some 20.7% of infants were undernourished by at least one nutritional measure initially, which declined to 16.4% at follow-up. Also 8.1% of the infants remained undernourished, 8.3% became undernourished, and 5.6% became well-nourished at follow-up. Low birthweight full-term infants were significantly likely to remain undernourished (p < 0.001) or become well-nourished (p < 0.001) at follow-up while the offspring of elderly mothers (p = 0.024) or first-time mothers (p = 0.036) had an elevated risk of remaining undernourished by at least one measure at follow-up.

CONCLUSIONS

Many infants are likely to exhibit individual nutritional changes at variance with the overall/summary trend. Those whose nutritional status is likely to deteriorate or remain poor require timely intervention to minimize the risk of subsequent developmental delays/deficits from early infancy.

Early growth velocities and weight gain plasticity improve linear growth in Peruvian infants

Growth velocity patterns have the potential to signal unhealthy responses to environmental insults with long-term consequences. We aimed to investigate velocities in Peruvian infants (n = 259) in relation to attained anthropometric outcomes at 12 months and to identify determinants of velocities during critical periods of infancy. From 1995 to 1997, a randomised controlled trial of maternal zinc supplementation was conducted in a peri-urban slum area of Lima. Infants were followed monthly through 1 year on a range of anthropometric measures. Three types of velocity variables were studied: (1) incremental velocity (1 months and 3 months); (2) proportional changes (% of total size gained/month); and (3) individual velocity variability [standard deviation (SD) of individual child incremental velocities]. Mean individual child SD of weight velocity was 417 g (±126). In multivariate ordinary least squares regression analyses, growth velocities in month 1 and individual weight velocity variability positively predicted attained length and weight by 12 months. Panel regression by generalised least-squares with random effects of length and weight velocities confirmed the exponentially decelerating pace of growth through infancy and the importance of birth size in driving this trajectory. This study contributes evidence to support the importance of early growth velocities and greater degrees of weight gain plasticity for attained length and weight.