Timing of growth faltering in rural Malawi

Weight Velocity in Addition to Latest Weight Does Not Improve the Identification of Wasting or the Prediction of Stunting and Mortality: A Longitudinal Analysis Using Data from Malawi, South Africa, and Pakistan

BACKGROUND

In low/middle-income countries, most nutritional assessments use the latest weights, without reference to growth trajectory.

OBJECTIVES

This study explores whether velocity, in addition to the latest weight, improves the prediction of wasting, stunting, or mortality in the first 2 years of life.

METHODS

We analyzed a combined data set with weight and height data collected monthly in the first year of 3447 children from Pakistan, Malawi, and South Africa, with height and survival recorded till 24 m. The main exposures were weight-for-age z-score (WAZ) at the end of each 2-m period and weight velocity-for-age z-score (WVZ2) across that period. The outcomes were wasting, stunting, or all-cause mortality in the next 1-2 mo. As a sensitivity analysis, we also used WVZ over 6 mo (WVZ6), with matching WAZ. Cox proportional hazard models with repeated growth measures were used to study the association between exposures and mortality. Mixed Poisson models were used for stunting and wasting.

RESULTS

Children who were already stunted or wasted were most likely to remain so. Higher WVZ2 was associated with a lower risk of subsequent stunting (risk ratio [RR]: 0.95; 95% confidence interval [CI]: 0.93, 0.96), but added minimal prediction (difference in AUC = 0.004) compared with a model including only WAZ. Similarly, lower WVZ2 was associated with wasting (RR: 0.74; 95% CI 0.72, 0.76) but the prediction was only marginally greater than for WAZ (difference in AUC = 0.015). Compared with WAZ, WVZ6 was less predictive for both wasting and stunting. Low WVZ6 (but not WVZ2) was associated with increased mortality (hazard ratios: 0.75, 95% CI: 0.67, 0.85), but added only marginal prediction to a model including WAZ alone (difference in C = 0.015).

CONCLUSIONS

The key anthropometric determinant of impending wasting, stunting, and mortality appears to be how far below the normal range the child's weight is, rather than how they reached that position.

Low length-for-age Z-score within 1 month after birth predicts hyperdynamic circulation at the age of 21 years in rural Malawi

Low birth weight predisposes to the development of hypertension in middle- and high-income countries. We examined the relation of early life length-for-age score (Z-score) on cardiovascular function in young adults in Malawi, a low-income country. Capture of supine, seated, and standing brachial pulse waveforms (Mobil-O-Graph) were performed in 223 females and 152 males (mean age 21 years), and analyzed according to the length-for-age Z-score tertiles during the first month of life. Plasma LDL cholesterol in young adulthood was slightly lower in the lowest versus highest tertile. Otherwise, blood hemoglobin and plasma chemistry were similar in all tertiles. Irrespective of posture, blood pressure, forward and backward wave amplitudes, and pulse wave velocity were corresponding in all tertiles. In the three postures, the lowest tertile presented with 4.5% lower systemic vascular resistance than the highest tertile (p = 0.005), and 4.4% and 5.5% higher cardiac output than the middle and highest tertiles, respectively (p < 0.01). Left cardiac work was 6.8% and 6.9% higher in the lowest tertile than in the middle and highest tertiles, respectively (p < 0.01). To conclude, in a low-income environment, low length-for-age Z-score after birth predicted hyperdynamic circulation at 21 years of age without changes in blood pressure and metabolic variables.

Age heterogeneities in child growth and its associated socio-demographic factors: a cross-sectional study in India

BACKGROUND

The impacts of socio-demographic and environmental risk factors on child growth have been widely documented. However, it remains unclear whether the impacts of such risk factors on child growth have remained static or changed with child's age. The present study aims to assess the underlying age heterogeneities in child growth and its potential determinants over age in under-five children.

METHODS

Cross-sectional data on child height (measured as height-for-age z-score, i.e., HAZ) and weight (measured as weight-for-age z-score, i.e., WAZ) and potential confounding factors from India's 2015-16 National Family Health Survey (NFHS) were used to construct anthropometric age-profiles by a number of bio-demographic and socioeconomic characteristics. Further, age-interacted multilevel regression analyses were performed to examine differential effects of such/those risk factors on child height and weight by age.

RESULTS

Faltered height and weight growth during first two years of life was noticed in children of all socioeconomic groups studied, albeit with varying magnitude. In case of child's height, factors such as short birth interval, higher birth order, maternal education, household wealth, district level mortality rate have shown strong interaction with child's age during the first 23 months, signifying their age-varying role in different developmental stages of child growth. These factors explain the observed upward and downward shifts in height curve during first two years. Some of these variables (e.g., household wealth) have shown even stronger age interactions after the second birthday of children. For child's weight, interactive effects of most socio-demographic risk factors attenuated parabolically with child's age.

CONCLUSIONS

The impacts of several risk factors, measured at the child, mother, community, and district levels, on child growth indicators varied significantly with the child's age. Nutritional interventions aimed at preventing poor linear growth in children in India should consider these underlying age heterogeneities for growth determinants into account.

Timing and pattern of growth faltering in children up-to 18 months of age and the associated feeding practices in an urban setting of Sri Lanka

BACKGROUND

Growth faltering is commonly encountered in breastfed infants during 4-6 months of age in low socioeconomic communities. The objective of this study was to describe the changes of growth indices with age, timing of growth faltering and its association with the feeding practices in children up-to 18 months of age.

METHODS

A cross sectional descriptive study was conducted in 254 children aged 12 and 18 months attending an immunization clinic. Data on growth were extracted from the Child Health Development Record. Weight and length were measured using standard methods. Feeding practices were assessed using interviewer-administered questionnaire. A drop of > 0.25 in weight-for-age Standard Deviation Score (SDS) from birth SDS was defined as weight faltering.

RESULTS

Weight faltering occurred at some point in 64.2% (n = 163) during first 18 months of life, and 78.5% of whom, had the onset ≤ 4 months of age. Majority (76.6%, n = 98) with weight for age faltering by 4 months remained so at 12 months (p = 0.497), while 29.7% (n = 38) had a weight-for-length below-2SD (p < 0.001). Prevalence of weight faltering was 50.4%, 46.1%, 48.4% and 48% at 4, 6, 9 and 12 months respectively. Exclusive breastfeeding was given at least until 4 months in 88% (n = 223) and up to 6 months in 60% (n = 153) while 92.9% (n = 236) were breastfed at 12 months, with 38.2% (n = 97) were breastfed on demand after six months. Complementary feeding (CF) was started before 6 months in 40.6% (n = 52) with early weight faltering, but only 20.3% received it with proper consistency. Breastfeeding throughout the night was significantly associated with current weight-for-length being < -1SD (OR = 1.89, CI, 1.04-3.45; p = 0.037).

CONCLUSIONS

Early growth faltering was found in this population with high exclusive breastfeeding rates and persisting growth faltering was associated with poor feeding practices. Therefore, timely individualized interventions need to be taken to improve long term growth.

Posture-Related Differences in Cardiovascular Function Between Young Men and Women: Study of Noninvasive Hemodynamics in Rural Malawi

Background

Cardiovascular risk is higher in men than in women, but little information exists about sex‐related differences in cardiovascular function from low‐income countries. We compared hemodynamics between sexes in rural Malawi in a cohort followed up since their birth.

Methods and Results

Supine, seated, and standing hemodynamics were recorded from 251 women and 168 men (mean age, 21 years; body mass index, 21 kg/m²) using oscillometric brachial waveform analyses (Mobil‐O‐Graph). The results were adjusted for estimated glomerular filtration rate, and plasma potassium, lipids, and glucose. Men had higher brachial and aortic systolic blood pressure and stroke index regardless of posture (P<0.001), and higher upright but similar supine diastolic blood pressure than women. Regardless of posture, heart rate was lower in men (P<0.001), whereas cardiac index did not differ between sexes. Women presented with lower supine and standing systemic vascular resistance index (P<0.001), whereas supine‐to‐standing increase in vascular resistance (P=0.012) and decrease in cardiac index (P=0.010) were higher in women. Supine left cardiac work index was similar in both sexes, whereas standing and seated left cardiac work index was higher in men than in women (P<0.001).

Conclusions

In young Malawian adults, men had higher systolic blood pressure, systemic vascular resistance, and upright cardiac workload, whereas women presented with higher posture‐related changes in systemic vascular resistance and cardiac output. These findings show systematic sex‐related differences in cardiovascular function in a cohort from a low‐income country with high exposure to prenatal and postnatal malnutrition and infectious diseases.

Monthly measurement of child lengths between 6 and 27 months of age in Burkina Faso reveals both chronic and episodic growth faltering

BACKGROUND

Linear growth faltering is determined primarily by attained heights in infancy, but available data consist mainly of cross-sectional heights at each age.

OBJECTIVES

This study used longitudinal data to test whether faltering occurs episodically in a few months of very low growth, which could potentially be prevented by timely intervention, or is a chronic condition with slower growth in every month of infancy and early childhood.

METHODS

Using anthropometric data collected monthly between August 2014 and December 2016, we investigated individual growth curves of 5039 children ages 6-27 mo in Burkina Faso (108,580 observations). We evaluated growth-curve smoothness by level of attained length at ∼27 mo by analyzing variation in changes in monthly growth rates and using 2-stage regressions: 1) regressing each child's length on their age and extracting R2 to represent curve smoothness, initial length, and average velocity by age; and 2) regressing extracted parameters on individual-level attained length.

RESULTS

Short children started smaller and remained on their initial trajectories, continuously growing slower than taller children. Growth between 9 and 11 mo was the most influential on attained length; for each 1-cm/mo increase in growth velocity during this period, attained length increased by 6.71 cm (95% CI: 6.59, 6.83 cm). Furthermore, a 0.01 increase in R2 from individual regression of length on age was associated with a 3.10-cm higher attained length (95% CI: 2.80, 3.41 cm), and having 2 consecutive months of slow growth (<15th centile relative to the sample) was associated with 1.7-cm lower attained length (95% CI: -1.80, -1.59 cm), with larger effects in younger children, suggesting that smoother growth patterns were also associated with higher attained length.

CONCLUSIONS

Children who experience extreme growth faltering are likely less resilient to systematic growth-limiting conditions as well as episodic insults to their growth.This trial was registered at clinicaltrials.gov as NCT02071563.

Wasting and Stunting in Infants and Young Children as Risk Factors for Subsequent Stunting or Mortality: Longitudinal Analysis of Data from Malawi, South Africa, and Pakistan

BACKGROUND

Few studies have had sufficient longitudinal data to track how different malnourished states relate to mortality at different ages and interrelate over time.

OBJECTIVES

This study aims to describe the RRs and proportions of mortality associated with wasting and stunting and the pathways into and out of these nutritional states.

METHODS

Longitudinal growth data sets collected for children ages 0-24 months from Malawi, South Africa, and Pakistan were combined (n = 5088). Children were classified as deceased, wasted (weight for height < -2 SD; 1-4%), stunted (length < -2SD; 20-47%), or wasted and stunted (WaSt; 2-5%) at ages 3, 6, 9, 12, 18, and 24 months. Mixed-effects Cox models were used to study the association between nutritional status and mortality.

RESULTS

By age 3 months, 20% of children were already stunted, rising to 49% by 24 months, while wasting (4.2% and 2.2% at 3 months, respectively) and WaSt (0.9% and 3.7% at 24 months, respectively) were less common. The HR for mortality in WaSt was 9.5 (95% CI, 5.9-15), but 60% of WaSt-associated mortality occurred at 3-6 months. Wasting or WaSt was associated with 10-23% of deaths beyond 6 months, but in the second year over half of deaths occurred in stunted, nonwasted children. Stunting persisted in 82% of children and wasting persisted in 44%. Wasted children were more likely than nonwasted, nonstunted children to become stunted (RR, 1.93; 95% CI, 1.7-2.2), but 94% of children who progressed to stunting had not been wasted in the prior period.

CONCLUSIONS

WaSt greatly increased the risk of death, particularly in very young infants, but more deaths overall were associated with stunting. Most stunting appeared to be either intrauterine in origin or arose in children without prior wasting. Either stunting and wasting represent alternative responses to restricted nutrition, or stunting also has other, nonnutritional causes.

Aflatoxin M1 in raw cow milk and associated hepatocellular carcinoma risk among dairy farming households in Malawi

In the present study, a total of 112 raw milk samples were collected between October and December of 2018 from dairy farming households in Malawi and analyzed for aflatoxin M1 (AFM1) using VICAM aflatest fluorometry procedure. These data together with the consumption data obtained through a milk consumption frequency questionnaire were used for the calculation of AFM₁ exposure and its association with hepatocarcinoma (HCC) risk in dairy farming population. Average daily milk intake by children and adults were approximately 300 ± 0.07 and 541.7 ± 0.14 mL, respectively. All raw milk samples tested positive to AFM₁ averaging 0.551 μg/L. Probable mean daily exposure to AFM₁ for adults was 4.98 ± 7.25 ng/kg BW/day almost half that of children (8.28 ± 11.82 ng/kg BW/day). Estimated risk of AFM₁-induced HCC associated with consumption of milk among children and adults were 0.038 and 0.023 cases per 100,000 individuals per year, respectively. Although the results of this investigation suggest a low risk of HCC, other negative health effects of AFM₁ justify its continuous monitoring and update of the risk assessment. This work presents the first insight in the occurrence of AFM₁ in cow milk in Malawi as well as associated AFM₁ exposure in dairy farming population.

Effect of Differences in Month and Location of Measurement in Estimating Prevalence and Trend of Wasting and Stunting in India in 2005-2006 and 2015-2016

BACKGROUND

Child undernutrition in India remains widespread. Data from the National Family Health Survey 3 and 4 (NFHS-3 and NFHS-4) suggest that wasting prevalence has increased while stunting prevalence has declined.

OBJECTIVE

The objectives of this study were to do the following: 1) describe wasting and stunting by month of measurement in India in children <5 y of age in NFHS-3 and NFHS-4 surveys, and 2) test whether differences in the timing of anthropometric data collection and in states between survey years introduced bias in the comparison of estimates of wasting and stunting between NFHS-3 and NFHS-4.

METHODS

Data on wasting and stunting for 42,608 and 232,744 children aged >5 y in the NFHS-3 and NFHS-4 survey rounds were analyzed. Differences in the prevalence of wasting and stunting by month of year and by state of residence were examined descriptively. Regression analyses were conducted to test the sensitivity of the estimate of differences in wasting and stunting prevalence across survey years to both state differences and seasonality.

RESULTS

Examination of the patterns of wasting and stunting by month of measurement and by state across survey years reveal marked variability. When both state and month were adjusted, regardless of the method used to account for sample size, there was a small negative difference from 2005-2006 to 2015-2016 in the prevalence of wasting (-0.8 ± 0.6 percentage points; P = 0.2) and a negative difference in stunting prevalence (-8.3 ± 0.7 percentage points; P < 0.001), indicating a small bias for wasting but not for stunting in unadjusted analyses.

CONCLUSIONS

State and seasonal differences may have introduced bias to the estimated difference in prevalence of wasting between the survey years but did not do so for stunting. Future data collection should be designed to maximize consistency in coverage of both time and place.

Supplementation With Lactoferrin and Lysozyme Ameliorates Environmental Enteric Dysfunction: A Double-Blind, Randomized, Placebo-Controlled Trial

INTRODUCTION

Environmental enteric dysfunction (EED) predisposes children throughout the developing world to high rates of systemic exposure to enteric pathogens and stunting. Effective interventions that treat or prevent EED may help children achieve their full physical and cognitive potential. The objective of this study is to test whether 2 components of breast milk would improve a biomarker of EED and linear growth during the second year of life.

METHODS

A prospective, randomized, double-blind, placebo-controlled clinical trial among children aged 12-23 months was conducted in rural Malawi. The experimental group received a daily supplement of 1.5 g of lactoferrin and 0.2 g of lysozyme for 16 weeks. The primary outcome was an improvement in EED, as measured by the change in the percentage of ingested lactulose excreted into the urine (Δ%L).

RESULTS

Among 214 children who completed the study, there was a significant difference in Δ%L between the control and experimental groups over 8 weeks (an increase of 0.23% vs 0.14%, respectively; P = 0.04). However, this relative improvement was not as strongly sustained over the full 16 weeks of the study (an increase of 0.16% vs 0.11%, respectively; P = 0.17). No difference in linear growth over this short period was observed. The experimental intervention group had significantly lower rates of hospitalization and the development of acute malnutrition during the course of the study (2.5% vs 10.3%, relative risk 0.25; P < 0.02).

DISCUSSION

Supplementation with lactoferrin and lysozyme in a population of agrarian children during the second year of life has a beneficial effect on gut health. This intervention also protected against hospitalization and the development of acute malnutrition, a finding with a significant clinical and public health importance. This finding should be pursued in larger studies with longer follow-up and optimized dosing.

[Correlation of size and age in Colombian indigenous children based on WHO and NCHS references]

Objective To evaluate the correlation of size, according to age, of the anthropometric growth references of Colombian indigenous children studied in Encuesta Nacional de la Situación Nutricional de Colombia 2010 -ENSIN 2010 (National Survey of Nutrition in Colombia - 2010). Method A secondary analysis of 2598 data of indigenous Colombian children under five years of age, evaluated by ENSIN in 2010, was performed. The considered variables were size according to age, gender, height, place of residence, department and socioeconomic position. The classification of the deficit in size, based on the references of the National Center for Health Statistics (NCHS) and the World Health Organization (WHO), was made by using the Z <-2 score and the Anthro software. The Kappa coefficient was estimated to assess the correlation between anthropometric categories and was classified taking into account the proposal of Altman DG. Results One in four children had a deficit in size in the light of both anthropometric references. The prevalence of the deficit was higher when using the WHO standard, increased with age and was higher in children who resided in low altitude (m). The correlation between the two references was good (kappa ≥0,688, p=0,000) for children of both genders and all ages; the exception corresponded to children of age two, since it was moderate (kappa=0,601, p=0,000). The greatest disagreement in the classification was observed in the category "tall". Conclusion According to the statistical correlation found between the two anthropometric references (WHO vs. NCHS), any reference could be used for assessment of size according to for age.

Height gain after two-years-of-age is associated with better cognitive capacity, measured with Raven's coloured matrices at 15-years-of-age in Malawi

Stunting is a measure of chronic undernutrition, and it affects approximately 160 million children worldwide. Cognitive development of stunted children is compromised, but evidence about the association between height gain in late childhood and adolescent cognitive capacity is scarce. We aimed to determine the association between height gains at different ages, including late childhood, and cognitive capacity at 15-years-of-age. We conducted a prospective cohort study in a rural African setting in Southern Malawi. The study cohort was enrolled between June 1995 and August 1996. It originally comprised mothers of 813 fetuses, and the number of children born live was 767. These children were followed up until the age of 15 years. The anthropometrics were measured at one and 24-months-of-age and 15-years-of-age, and cognitive capacity of participants was assessed at 15-years-of-age with Raven's Coloured Matrices score, mathematic test score, median reaction time (RT) (milliseconds) and RT lapses. The associations between growth and the outcome measures were assessed with linear regression. Raven's Coloured Matrices score was predicted by height gain between 24 months and 15-years-of-age (coefficient 0.85, P = 0.03) and (coefficient 0.69, P = 0.06), but not by earlier growth, when possible confounders were included in the model. The association weakened when school education was further added in the model (coefficient = 0.69, P = 0,060). In conclusion, in rural Malawi, better growth in late childhood is likely to lead to better cognitive capacity in adolescence, partly through more school education. In light of these results, growth promotion should not only be limited to early childhood.

Age-Specific Correlates of Child Growth

Growth faltering describes a widespread phenomenon that height- and weight-for-age of children in developing countries collapse rapidly in the first two years of life. We study age-specific correlates of child nutrition using Demographic and Health Surveys from 56 developing countries to shed light on the potential drivers of growth faltering. Applying nonparametric techniques and exploiting within-mother variation, we find that maternal and household factors predict best the observed shifts and bends in child nutrition age curves. The documented interaction between age and maternal characteristics further underlines the need not only to provide nutritional support during the first years of life but also to improve maternal conditions.

Linear growth trajectories in Zimbabwean infants

BACKGROUND

Undernutrition in early life underlies 45% of child deaths globally. Stunting malnutrition (suboptimal linear growth) also has long-term negative effects on childhood development. Linear growth deficits accrue in the first 1000 d of life. Understanding the patterns and timing of linear growth faltering or recovery during this period is critical to inform interventions to improve infant nutritional status.

OBJECTIVE

We aimed to identify the pattern and determinants of linear growth trajectories from birth through 24 mo of age in a cohort of Zimbabwean infants.

DESIGN

We performed a secondary analysis of longitudinal data from a subset of 3338 HIV-unexposed infants in the Zimbabwe Vitamin A for Mothers and Babies trial. We used k-means clustering for longitudinal data to identify linear growth trajectories and multinomial logistic regression to identify covariates that were associated with each trajectory group.

RESULTS

For the entire population, the mean length-for-age z score declined from -0.6 to -1.4 between birth and 24 mo of age. Within the population, 4 growth patterns were identified that were each characterized by worsening linear growth restriction but varied in the timing and severity of growth declines. In our multivariable model, 1-U increments in maternal height and education and infant birth weight and length were associated with greater relative odds of membership in the least-growth restricted groups (A and B) and reduced odds of membership in the more-growth restricted groups (C and D). Male infant sex was associated with reduced odds of membership in groups A and B but with increased odds of membership in groups C and D.

CONCLUSION

In this population, all children were experiencing growth restriction but differences in magnitude were influenced by maternal height and education and infant sex, birth weight, and birth length, which suggest that key determinants of linear growth may already be established by the time of birth. This trial was registered at clinicaltrials.gov as NCT00198718.

Transition between stunted and nonstunted status: both occur from birth to 15 years of age in Malawi children

AIM

The timing and frequency of stunting and possible catch-up growth are ambiguous in low-income settings. This study explored the timing and extent of becoming stunted and nonstunted between birth and 15 years of age in a resource-poor area of Malawi, south-east Africa.

METHODS

We followed 767 children from the foetal period until 15 years of age and examined the transition between stunted and nonstunted status and the pubertal stage at 15 years of age. We also plotted smoothed curves for the mean absolute deficits in centimetres and height-for-age standard deviation scores (HAZ) according to the World Health Organization's 2006 and 2007 references.

RESULTS

Most two-year olds (80%) were stunted (HAZ < -2 SD), but this had declined to 37% at 15 years of age. During the three five-year intervals, new stunting cases ranged from 3.9 to 21.3% and the percentage who became nonstunted was 9.1 to 15%. The majority (85%) of the children, who were moderately stunted at two years of age, became nonstunted during the follow-up period. Only, 9% of boys and 20% of girls had reached advanced puberty by the age of 15.

CONCLUSION

Becoming stunted and nonstunted status both occurred throughout the period from birth to 15 years of age in Malawi children. The small percentage who had reached advanced puberty by the age of 15 suggests significant further growth potential.

Effects of Birth Month on Child Health and Survival in Sub-Saharan Africa

Birth month is broadly predictive of both under-5 mortality rates and stunting throughout most of sub-Saharan Africa (SSA). Observed factors, such as mother's age at birth and educational status, are correlated with birth month but are not the main factors underlying the relationship between birth month and child health. Accounting for maternal selection via a fixed-effects model attenuates the relationship between birth month and health in many SSA countries. In the remaining countries, the effect of birth month may be mediated by environmental factors. This study found that birth month effects on mortality typically do not vary across age intervals; the differential mortality rates by birth month are evident in the neonatal period and continue across age intervals. The male-to-female sex ratio at birth did not vary by birth month, which suggests that in utero exposures are not influencing fetal loss, and that therefore the birth month effects are not likely a result of selective survival during the in utero period. In one-third of the sample, the birth month effects on stunting diminished after the age of 2 years; therefore, some children were able to catch up. Policies to improve child health should target pregnant women and infants and must take seasonality into account.

Exclusive breastfeeding duration during the first 6 months of life is positively associated with length-for-age among infants 6-12 months old, in Mangochi district, Malawi

OBJECTIVES

To examine the association between breastfeeding pattern and growth in the first year of life.

METHODS

A cross-sectional survey was carried out on 349 mothers with infants <12 months in a rural and a semi-urban community in Mangochi district, Malawi. Data on socio-demographic characteristics, infant weight, length and feeding patterns since birth were collected. Multivariate linear regression was performed to test the association between feeding pattern and infant anthropometric status.

RESULTS

Exclusive breastfeeding (EBF) until 6 months was practised by 13.1% semi-urban and 1.3% rural mothers. No infant was exclusively breastfed beyond 6 months. Breastfeeding was continued among all infants who had stopped EBF. Among infants 6-12 months of age, duration of EBF during the first 6 months was positively associated with length-for-age Z-score (LAZ) (regression coefficient=0.19, 95% confidence interval: 0.06, 0.31) in a model adjusted for socio-demographic factors. Urban residence and female gender yielded positive associations in the same model. The model explained 27% of the variation in LAZ. Among infants <6 months, duration of EBF was not significantly associated with LAZ, but being female and urban residence yielded positive associations. Breastfeeding patterns were not associated with weight-for-age Z-score (WAZ) or weight-for-height Z-score (WLZ) either in the 0-6-month or in the 6-12-month group. Birth outside a health facility was negatively associated with WAZ and WLZ in the older group.

CONCLUSION

EBF in the first 6 months of life was associated with increased linear growth, but not weight gain, in later infancy. Promotion of EBF could reduce the prevalence of chronic child undernutrition in the study area.

Lipid-based nutrient supplements do not decrease breast milk intake of Malawian infants

BACKGROUND

The potential for small-quantity lipid-based nutrient supplements (LNS) to promote growth and development after 6 mo of age is currently being investigated. Because infants self-regulate energy intake, consumption of LNS may reduce breast milk intake and potentially decrease the beneficial effects of breast milk.

OBJECTIVE

The objective was to test the hypothesis that the breast milk intake of 9- to 10-mo-old rural Malawian infants receiving LNS would not be lower than that of infants receiving no supplementation.

DESIGN

This was a substudy of the International Lipid-based Nutrient Supplements (iLiNS) DOSE trial, in which 6-mo-old infants were randomly assigned to receive 10, 20, or 40 g LNS/d containing 56, 117, or 241 kcal/d, respectively, or no LNS until 18 mo of age. A subset was randomly selected to estimate breast milk intake at 9-10 mo of age with the dose-to-mother deuterium oxide dilution method. The noninferiority margin was <10% of total energy requirements.

RESULTS

Baseline characteristics (n = 376) were similar across groups. The mean (± SD) daily breast milk intake of unsupplemented infants was 730 ± 226 g. The differences (95% CIs) in mean intake of infants provided with 10, 20, or 40 g LNS/d, compared with controls, were +62 (-18, +143), +30 (-40, +99), and +2 (-68, +72) g/d, respectively. Non-breast milk oral water intake did not differ by group (P = 0.39) and was inversely (r = -0.22, P < 0.01) associated with breast milk intake.

CONCLUSION

In this rural Malawian population, breast milk intake at 9-10 mo of age was not reduced by supplementation with complementary foods with 10-40 g LNS/d.

Feasibility and validity of the ActiGraph GT3X accelerometer in measuring physical activity of Malawian toddlers

AIM

To test the feasibility and validity of the ActiGraph GT3X accelerometer in measuring physical activity of rural Malawian toddlers.

METHODS

Fifty-six children aged 16.0-18.5 months wore the accelerometer on their right hip for 7 days. We analysed days with a minimum of 600 min of wear time, excluding night time and periods when the unit registered zero for 20 consecutive minutes. The first and last days were excluded as they were incomplete. Accelerometer counts were compared with coded free play video recordings to define median accelerometer counts for sedentary, light, moderate and vigorous activity. Count cut points were defined for moderate to vigorous physical activity, with predictive validity assessed using a second set of video recordings.

RESULTS

Median wear time was 797 min/day, with 79% of participants completing at least four eligible days. Accelerometer counts were significantly higher for observed moderate to vigorous physical activity, than lighter activity, with cut points of 208 counts/15 sec for vector magnitude and 35 counts/15 sec for vertical axis, showing sensitivity of 94.2% and 84.1% and specificity of 90.9% and 84.6%, respectively.

CONCLUSION

The accelerometer proved a feasible and valid method of assessing physical activity among Malawian toddlers.

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.

Neonatal length inaccuracies in clinical practice and related percentile discrepancies detected by a simple length-board

AIM

The study aims to assess accuracy of standard practice measurement of neonatal length compared with a gold-standard length-board technique.

METHODS

Data were obtained from a population-based, cross-sectional study of 602 term babies at Royal Prince Alfred Hospital, Sydney, Australia, in 2010. Neonatal length was measured by standard clinical practice and by a length-board (gold standard) and measurements compared. Standard growth curve percentiles were used to plot length measurements. The Bland and Altman method was used to assess agreement, and acceptable levels of agreement were set at ≤1 cm and ≤0.5 cm.

RESULTS

The limits of agreement were between -3.06 cm (95% CI -3.08 to -3.04) and 2.67 cm (95% CI 2.65 to 2.69). Neonates whose standard-practice length fell within 0.5 cm of the gold standard totalled 41% (241 neonates), while 59% (342) were >0.5 cm. The change in length resulted in a change in the percentile range of 53% (309) on a standard growth curve percentile. When examining neonates whose length was plotted at the extremes of percentile regions, the positive predictive value results of the standard practice compared with the gold standard were poor, with positive predictive values of 37.5%, 57.1% and 31.3% for neonates who were measured as <3rd, <10th and ≥90th percentile, respectively.

CONCLUSIONS

In current clinical practice, measures of neonatal length are often inaccurate, which has implications for potentially erroneous clinical care. Health-care providers should be educated on the importance of length and trained in how to measure length with the correct technique using a length-board.

Child development at 5 years of age predicted mathematics ability and schooling outcomes in Malawian adolescents

AIM

This study aimed to examine the association between child development at 5 years of age and mathematics ability and schooling outcomes at 12 years of age in Malawian children.

METHODS

A prospective cohort study looking at 609 rural Malawian children. Outcome measures were percentage of correctly answered mathematics questions, highest school grade completed and number of times repeating school grades at 12 years of age. A child development summary score obtained at 5 years of age was the main exposure variable. Regression analyses were used to estimate the association and adjust for confounders. Sensitivity analysis was performed by handling losses to follow-up with multiple imputation (MI) method.

RESULTS

The summary score was positively associated with percentage of correctly answered mathematics questions (p = 0.057; p = 0.031 MI) and with highest school grade completed (p = 0.096; p = 0.070 MI), and negatively associated with number of times repeating school grades (p = 0.834; p = 0.339 MI). Fine motor score at 5 years was independently associated with the mathematic score (p = 0.032; p = 0.011 MI). The association between child development and mathematics ability did not depend on school attendance.

CONCLUSION

Child development at 5 years of age showed signs of positive association with mathematics ability and possibly with highest school grade completed at 12 years of age.

Use of lipid-based nutrient supplements by HIV-infected Malawian women during lactation has no effect on infant growth from 0 to 24 weeks

The Breastfeeding, Antiretrovirals, and Nutrition Study evaluated the effect of daily consumption of lipid-based nutrient supplements (LNS) by 2121 lactating, HIV-infected mothers on the growth of their exclusively breast-fed, HIV-uninfected infants from 0 to 24 wk. The study had a 2 × 3 factorial design. Malawian mothers with CD4(+) ≥250 cells/mm(3), hemoglobin ≥70 g/L, and BMI ≥17 kg/m(2) were randomized within 36 h of delivery to receive either no LNS or 140 g/d of LNS to meet lactation energy and protein needs, and mother-infant pairs were assigned to maternal antiretroviral drugs (ARV), infant ARV, or no ARV. Sex-stratified, longitudinal, random effects models were used to estimate the effect of the 6 study arms on infant weight, length, and BMI. Logistic regression models were used to calculate the odds of growth faltering [decline in weight-for-age Z-score (WAZ) or length-for-age Z-score (LAZ) >0.67] using the control arm as the reference. Although some differences between study arms emerged with increasing infant age in boys, there were no consistent effects of the maternal supplement across the 3 growth outcomes in longitudinal models. At the ages where differences were observed, the effects on weight and BMI were quite small (≤200 g and ≤0.4 kg/m(2)) and unlikely to be of clinical importance. Overall, 21 and 34% of infants faltered in WAZ and LAZ, respectively. Maternal supplementation did not reduce the odds of infant weight or length faltering from 0 to 24 wk in any arm. These results indicate that blanket supplementation of HIV-infected lactating women may have little impact on infant growth.

Developmental outcomes among 18-month-old Malawians after a year of complementary feeding with lipid-based nutrient supplements or corn-soy flour

The major aim of this trial was to compare the development of 18-month-old infants who received complementary feeding for 1 year either with lipid-based nutrient supplements or micronutrient fortified corn-soy porridge. Our secondary aim was to determine the socio-economic factors associated with developmental outcomes in the same population. A total of 163 six-month-old rural Malawian children were enrolled in a randomized controlled trial where the control population received daily supplementation with 71 g corn-soy flour [Likuni Phala (LP)] (282 kcal) and individuals in the intervention groups received daily either 50 g of lipid-based nutrient supplement (FS50) (264 kcal) or 25 g of lipid-based nutrient supplement (FS25) (130 kcal). The main outcome measures were Griffiths' developmental scores at 0-2 years. Independent comparison of study groups was carried out using analysis of variance (ANOVA) statistics where mean raw scores, quotients, or mental ages were compared. Association of developmental outcome with predictor variables were examined using multiple regression. At 18 months of chronological age, the mean ± standard deviation (SD) mental ages in the LP, FS50, and FS25 groups were 17.9 ± 1.3, 17.9 ± 1.3, and 17.9 ± 1.2 (P > 0.99), respectively. Likewise, the mean raw developmental scores and mean developmental quotients did not differ significantly. Length-for-age z-score gain during the intervention period, and maternal education were associated with developmental outcome at 18 months (P = 0.03 and P = 0.04; respectively). In conclusion, rural Malawian infants receiving 12-month daily supplementation of their diet either with the tested lipid-based nutrient supplements or fortified corn-soy flour have comparable development outcomes by 18 months of age.

Revisiting the relationship of weight and height in early childhood

Ponderal and linear growth of children has been widely studied; however, epidemiologic evidence of a relationship between the two is inconsistent. Child undernutrition in the form of low height for age and low weight for height continues to burden the developing world. A downward shift in the distribution of height for age in the first 2 y of life is commonly observed in many developing countries and is usually summarized as the percentage stunted (height for age Z-score <-2). Similar shifts are seen in weight for height; however, weight-for-height shifts are often less extreme, perhaps because weight for height is more tightly biologically controlled. Low height for age and low weight for height in childhood share some common factors, including food insecurity, infectious diseases, and inappropriate feeding practices. Reductions in weight for height, generally seen as a short-term response to inadequate dietary intake or utilization, are thought to precede decreases in height for age; however, given an adequate diet and no further insults, catch-up linear growth can occur. Serial instances of decreased weight for height, however, are thought to limit the degree of catch-up growth attained, contributing to linear growth retardation. Additional research is needed to identify the factors associated with recovery of linear growth after a child experiences decreased weight for height. Although the direct relationship between weight for height and height for age is likely limited, each of these measurements indicates important information about the general health of children and their risk of the development of illness or dying; therefore, eliminating the downward shift of height for age and weight for height in developing countries should be prioritized as a public policy.

Height gain during early childhood is an important predictor of schooling and mathematics ability outcomes

AIM

To examine the association between height gain at different stages of early childhood and schooling and cognitive outcomes in 12-year-old Malawian children.

METHODS

A prospective cohort study looking at the growth and development of 325 rural Malawian children. Main outcome measures were highest school grade completed, number of times repeating grades and percentage of correctly answered mathematical questions at 12 years of age. Height-for-age at 1 month and conditional height gain for 6, 18 and 60 months were used as predictors. Ordinal logistic and linear regression analyses were used to estimate the association and adjust for confounder.

RESULTS

The conditional height gain during 18-60 months was positively associated with mathematics test results (p=0.003) and negatively associated with number of times repeating grades (p=0.011). It was not significantly associated with highest grade completed (p=0.194) if those who never attended school were included as having completed zero grade, but was positively (p=0.049) associated with this outcome among those who ever attended school.

CONCLUSION

Height gain during the 18-60 months period of age was related to schooling and mathematics ability at age 12 years. The importance of promoting catch-up growth after the period when stunting is common should receive attention.

Acceptability of three novel lipid-based nutrient supplements among Malawian infants and their caregivers

We tested the acceptability of three new lipid-based nutrient supplements (LNSs) in two independent phases among 18 8-12-month-old healthy rural Malawians and their caregivers. In phase 1, acceptability was assessed by offering three new LNSs in random order, and an LNS already determined to be acceptable, Nutributter(®), each added to 30 g of warm maize porridge over three consecutive days. In phase 2, infants from each village were provided one of the new supplements for a 2-week home-use trial. Outcome measures included the amount consumed, time completion of the dose and the maternal rating of likeability on a 5-point scale. The supplements were rated acceptable if consumption was over 50% of the offered dose in phase 1. The mean (95% confidence interval) proportion of the LNS test meals consumed under direct observation was 88% (82-94%) for LNS-10gM, 90% (84-95%) for LNS-20gM, 87% (79-95%) for LNS-20gNoM, and 86% (83-90%) for Nutributter. The median (25th and 75th centile) time (minutes) for completing the offered test meal was 4 (2, 7) for LNS-10gM, 5 (3, 6) for LNS-20gM, 4 (3, 8) for LNS-20gNoM and 4 (2, 6) for Nutributter. During both phases, almost all caregivers rated all study foods very likeable for themselves and their children, with mean scores slightly lower among the caregivers than among the infants. In the home-use phase, the test foods were almost exclusively used by the study participants with minimal sharing with siblings and other household members. Some infants were reported to prefer the new investigational products over traditional complementary food. Considering that the novel LNS was largely acceptable. Efficacy trials are now needed to assess their impact on child growth and development.

The duration of diarrhea and fever is associated with growth faltering in rural Malawian children aged 6-18 months

Nutrition support programs that only focus upon better complementary feeding remain an insufficient means of limiting growth faltering in vulnerable populations of children. To determine if symptoms of acute infections correlate with the incidence of growth faltering in rural Malawian children, the associations between fever, diarrhea, and cough with anthropometric measures of stunting, wasting, and underweight were investigated. Data were analyzed from a trial where 209 children were provided with adequate complementary food and followed fortnightly from 6-18 months of age. Linear mixed model analysis was used to test for associations. Diarrheal disease was inversely associated with changes in height-for-age Z-score (HAZ), mid-upper arm circumference Z-score (MUACZ), and weight-for-age Z-score (WAZ). Fever was also inversely associated with changes in MUACZ and WAZ. These results suggest that initiatives to reduce febrile and diarrheal diseases are needed in conjunction with improved complementary feeding to limit growth faltering in rural Malawi.

The validity of a structured interactive 24-hour recall in estimating energy and nutrient intakes in 15-month-old rural Malawian children

This study aimed to compare the nutritional intake values among 15-month-old rural Malawian children obtained by weighed food record (WFR) with those obtained by modified 24-hour recall (mod 24-HR), and to develop algorithm for adjusting mod 24-HR values so as to predict mean intake based on WFRs. The study participants were 169 15-month-old children who participated in a clinical trial. Food consumption on one day was observed and weighed (established criterion) by a research assistant to provide the estimates of energy and nutrient intakes. On the following day, another research assistant, blinded to the direct observation, conducted the structured interactive 24-hour recall (24-HR) interview (test method). Paired t-tests and scatter-plots were used to compare intake values of the two methods. The structured interactive 24-HR method tended to overestimate energy and nutrient intakes (each P < 0.001). The regression-through-the-origin method was used to develop adjustment algorithms. Results showed that multiplying the mean energy, protein, fat, iron, zinc and vitamin A intake estimates based on the test method by 0.86, 0.80, 0.68, 0.69, 0.72 and 0.76, respectively, provides an approximation of the mean values based on WFRs.

Ratio of weight to height gain: a useful tool for identifying children at risk of becoming overweight or obese at preschool age

PURPOSE

To analyze the usefulness of the weight gain/height gain ratio from birth to two and three years of age as a predictive risk indicator of excess weight at preschool age.

METHODS

The weight and height/length of 409 preschool children at daycare centers were measured according to internationally recommended rules. The weight values and body mass indices of the children were transformed into a z-score per the standard method described by the World Health Organization. The Pearson correlation coefficients (rP) and the linear regressions between the anthropometric parameters and the body mass index z-scores of preschool children were statistically analyzed (alpha = 0.05).

RESULTS

The mean age of the study population was 3.2 years (± 0.3 years). The prevalence of excess weight was 28.8%, and the prevalence of overweight and obesity was 8.8%. The correlation coefficients between the body mass index z-scores of the preschool children and the birth weights or body mass indices at birth were low (0.09 and 0.10, respectively). There was a high correlation coefficient (rP = 0.79) between the mean monthly gain of weight and the body mass index z-score of preschool children. A higher coefficient (rP = 0.93) was observed between the ratio of the mean weight gain per height gain (g/cm) and the preschool children body mass index z-score. The coefficients and their differences were statistically significant.

CONCLUSION

Regardless of weight or length at birth, the mean ratio between the weight gain per g/cm of height growth from birth presented a strong correlation with the body mass index of preschool children. These results suggest that this ratio may be a good indicator of the risk of excess weight and obesity in preschool-aged children.

Postintervention growth of Malawian children who received 12-mo dietary complementation with a lipid-based nutrient supplement or maize-soy flour

BACKGROUND

Therapeutic feeding with micronutrient-fortified lipid-based nutrient supplements (LNSs) has proven useful in the rehabilitation of severely malnourished children. We recently reported that complementary feeding of 6-18-mo-old infants with an LNS known as FS50 was associated with improved linear growth and a reduction in the incidence of severe stunting during the supplementation period.

OBJECTIVE

Our objective was to assess whether a reduction in stunting seen with 12-mo LNS supplementation was sustained over a subsequent 2-y nonintervention period.

DESIGN

One hundred eighty-two 6-mo-old healthy rural Malawian infants were randomly assigned to receive daily supplementation for 12 mo with 71 g of maize-soy flour [likuni phala (LP); control group, 282 kcal] or either 50 g of FS50 (264 kcal; main intervention group), or 25 g of FS25 (130 kcal). Main outcome measures were incidence of severe stunting and mean z score changes in weight-for-age, length-for-age, and weight-for-length during a 36-mo follow-up period.

RESULTS

The cumulative 36-mo incidence of severe stunting was 19.6% in LP, 3.6% in FS50, and 10.3% in FS25 groups (P = 0.03). Mean weight-for-age changes were -1.09, -0.76, and -1.22 (P = 0.04); mean length-for-age changes were -0.47, -0.37, and -0.71 (P = 0.10); and mean weight-for-length changes were -1.52, -1.18, and -1.48 (P = 0.27). All differences were more marked among individuals with baseline length-for-age below the median. Differences in length developed during the intervention at age 10-18 mo, whereas weight differences continued to increase after the intervention.

CONCLUSIONS

Twelve-month-long complementary feeding with 50 g/d FS50 is likely to have a positive and sustained impact on the incidence of severe stunting in rural Malawi. Half-dose intervention may not have the same effect. This trial was registered at (clinicaltrials.gov) as NCT00131209.

Under-reporting of gravidity in a rural Malawian population

BACKGROUND

Mis-reporting of data by study participants in a questionnaire-based study is an important source of bias in studies.

OBJECTIVE

To determine the prevalence and factors influencing mis-reporting of gravidity among rural women in Malawi.

MATERIALS AND METHODS

Data from cross sectional study conducted in 2004 were analysed using logistic regression analysis and the logit modeling.

RESULTS

7118 women were in the reproductive age group, 2387(33.5%) had ever attended school, 4556 (64.0%) had never and results for 175 (2.5%) were missing. Of those who attended school, 94.9% (2297) had attained a maximum primary level, 5.04% (122) secondary level and 0.08% (2) tertiary level. 81.6% of the women were aged between 12 and 36 years of age, mean was 26.1 years (SD 10.05 years). The remaining 18.4% were aged between 37 and 49 years of age. The mean number of pregnancies attained was 4.0 (SD 3.4), live births was 3.0 (SD 3.2), mean number of stillbirths was almost zero (SD 0.9) and the mean number of children alive was 2.0 (SD 2.3). The prevalence of mis-reporting of gravidity was 7.9%. Factors influencing the risk of under-reporting gravidity were: previous experience of a still-birth, young age, not being married and having ever attended some level of education.

CONCLUSIONS

We suggest that women who perceived that the community expected them, or they expected themselves to have fewer or no pregnancy at all, censured themselves in reporting low number of pregancies. Researchers using questionnaires should keep in mind possibility of mis-reporting of number of pregnancies among women as this may introduce error in research results. Incorporating multiple questions asking the same thing but in a different way has potential to identify biases as these other questions serve as consistency checks.

Maternal common mental disorder and infant growth--a cross-sectional study from Malawi

The objective of the study was to investigate the association between maternal common mental disorder (CMD) and infant growth in rural Malawi. A cross-sectional study was conducted at a district hospital child health clinic. Participants were consecutive infants due for measles vaccination, and their mothers. Mean infant weight-for-age and length-for-age z-scores were compared between infants of mothers with and without CMD as measured using the self-reporting questionnaire (SRQ). Of 519 eligible infants/mothers, 501 were included in the analysis. Median infant age was 9.9 months. 29.9% of mothers scored 8 or above on the SRQ indicating CMD. Mean length-for-age z-score for infants of mothers with CMD (-1.50 SD 1.24) was significantly lower than for infants of mothers without CMD (-1.11 SD 1.12) Student's t-test: P = 0.001. This association was confirmed in multivariate analysis. Mean weight-for-age z-score for infants of mothers with CMD (-1.77 SD 1.16) was lower than for infants of mothers without CMD (-1.59 SD 1.09) but this difference was not significant on univariate (Student's t-test: P = 0.097) or multivariate analysis. The study demonstrates an association between maternal CMD and infant growth impairment in rural sub-Saharan Africa.

Anthropometric measurements of children attending a vaccination clinic in Yaounde, Cameroon

BACKGROUND

Growth faltering is a frequent public health problem in children and anthropometric measurements are useful tools for follow-up and early diagnosis. This problem has not been studied in the Cameroonian setting, that's why we undertook this study.

OBJECTIVES

To have a synopsis of the nutritional status in apparently healthy children attending a vaccination clinic and show the importance of anthropometric measurements in routine child health care.

DESIGN

A retrospective study.

PATIENTS AND PARTICIPANTS

1351 children aged (6-24 months), who attended the vaccination clinic of the Yaounde Gynaeco-Obstetric and Pediatric Hospital over a 6 month period, were enrolled in the study.

METHOD

The registers of the vaccination clinic of the above hospital were retrospectively reviewed from 1st March to 31st August 2005. The following parameters were noted: age, height, weight, mid-upper arm circumference (MUAC), and Z scores calculated for the following indicators: weight for age (WAZ), weight for height (WHZ), and height for age (HAZ).

RESULTS

Our results show that 12 children (1.1 percent) in the 0-6 months age group and 4 (1.6 percent) in the 6-12 months age group had WAZ less than -2 indicating underweight. Also 10 children (0.9 percent) and 2 (0.8 percent) in the 0-6 and 6-12 months age groups respectively had WHZ less than -2, indicating wasting. HAZ was less than -2 in 70 children (6.4 percent) and in 8 (3.2 percent) in the 0-6 and 6-12 months age groups respectively indicating stunting. The MUAC was less than 12.5 cm in 6 children (2.4 percent).

CONCLUSIONS

From our results, we conclude that growth faltering is common in supposedly healthy children attending our vaccination clinic. Anthropometric measurements are thus recommended and should be encouraged in routine child care settings for early diagnosis of growth retardation and to provide useful interventions.

Implication of new WHO growth standards on identification of risk factors and estimated prevalence of malnutrition in rural Malawian infants

BACKGROUND

The World Health Organization (WHO) released new Child Growth Standards in 2006 to replace the current National Center for Health Statistics (NCHS) growth reference. We assessed how switching from the NCHS to the newly released WHO Growth Standards affects the estimated prevalence of wasting, underweight and stunting, and the pattern of risk factors identified.

METHODOLOGY/PRINCIPAL FINDINGS

Data were drawn from a village-informant driven Demographic Surveillance System in Northern Malawi. Children (n = 1328) were visited twice at 0-4 months and 11-15 months. Data were collected on the demographic and socio-economic environment of the child, health history, maternal and child anthropometry and child feeding practices. Weight-for-length, weight-for-age and length-for-age were derived in z-scores using the two growth references. In early infancy, prevalence estimates were 2.9, 6.1, and 8.5 fold higher for stunting, underweight, and wasting respectively using the WHO standards compared to NCHS reference (p<0.001 for all). At one year, prevalence estimates for wasting and stunting did not differ significantly according to reference used, but the prevalence of underweight was half that with the NCHS reference (p<0.001). Patterns of risk factors were similar with the two growth references for all outcomes at one year although the strength of association was higher with WHO standards.

CONCLUSIONS/SIGNIFICANCE

Differences in prevalence estimates differed in magnitude but not direction from previous studies. The scale of these differences depends on the population's nutritional status thus it should not be assumed a priori. The increase in estimated prevalence of wasting in early infancy has implications for feeding programs targeting lactating mothers and ante-natal multiple micronutrients supplementation to tackle small birth size. Risk factors identified using WHO standards remain comparable with findings based on the NCHS reference in similar settings. Further research should aim to identify whether the young infants additionally diagnosed as malnourished by this new standard are more appropriate targets for interventions than those identified with the NCHS reference.

Complementary feeding with fortified spread and incidence of severe stunting in 6- to 18-month-old rural Malawians

OBJECTIVE

To compare growth and incidence of malnutrition in infants receiving long-term dietary supplementation with ready-to-use fortified spread (FS) or micronutrient-fortified maize-soy flour (likuni phala [LP]).

DESIGN

Randomized, controlled, single-blind trial.

SETTING

Rural Malawi.

PARTICIPANTS

A total of 182 six-month-old infants.

INTERVENTION

Participants were randomized to receive 1 year of daily supplementation with 71 g of LP (282 kcal), 50 g of FS (FS50) (256 kcal), or 25 g of FS (FS25) (130 [corrected] kcal).

OUTCOME MEASURES

Weight and length gains and the incidences of severe stunting, underweight, and wasting.

RESULTS

Mean weight and length gains in the LP, FS50, and FS25 groups were 2.37, 2.47, and 2.37 kg (P = .66) and 12.7, 13.5, and 13.2 cm (P = .23), respectively. In the same groups, the cumulative 12-month incidence of severe stunting was 13.3%, 0.0%, and 3.5% (P = .01), of severe underweight was 15.0%, 22.5%, and 16.9% (P = .71), and of severe wasting was 1.8%, 1.9%, and 1.8% (P > .99). Compared with LP-supplemented infants, those given FS50 gained a mean of 100 g more weight and 0.8 cm more length. There was a significant interaction between baseline length and intervention (P = .04); in children with below-median length at enrollment, those given FS50 gained a mean of 1.9 cm more than individuals receiving LP.

CONCLUSION

One-year-long complementary feeding with FS does not have a significantly larger effect than LP on mean weight gain in all infants, but it is likely to boost linear growth in the most disadvantaged individuals and, hence, decrease the incidence of severe stunting.

An energy-dense complementary food is associated with a modest increase in weight gain when compared with a fortified porridge in Malawian children aged 6-18 months

Poor complementary feeding practices are associated with stunting and growth faltering throughout the developing world. The objective was to compare the effect of using peanut-/soy-based fortified spread (FS) and corn porridge fortified with fish powder (FP) as complementary foods on growth in rural Malawian children. A total of 240 children were enrolled at the age of 6 mo and randomized to receive FS or FP. Both complementary foods provided 836 kJ/d from 6 to 9 mo of age and 1254 kJ/d from 9 to 18 mo of age. Children were followed monthly for anthropometry and fortnightly for the symptoms of fever, cough, or diarrhea until they were 18 mo old. Zn and Se status were assessed at 6 and 12 mo. The primary outcomes were the rates of weight and length gain from 6-12 mo and from 12-18 mo. Children who received FS gained 110 g more (95% CI 220 to 10) from 6-12 mo of age than children receiving FP. Weight gain did not differ between children receiving FS and FP between 12 and 18 mo of age, nor did statural growth from 6 to 12 mo or 12 to 18 mo. A total of 23% of all children were Zn deficient at 6 mo of age and this increased to 37% at 12 mo of age. Neither FS nor FP was associated with significantly improved Zn status. FS was associated with better weight gain from 6-12 mo of age and may be useful in conjunction with additional interventions to improve infant growth in the developing world.

[Growth of full term low and adequate birth weight infants during the first two years of life]

OBJECTIVE

To assess the growth pattern of full term low and adequate birth weight infants during the first two years of life and to identify the determinants at the time of the greatest growth deceleration.

METHODS

A prospective cohort study was conducted with 148 full term infants in five small towns of the state of Pernambuco, Northeastern Brazil. Newborns were recruited from maternities between January 1993 and January 1994 and their anthropometric measurements were taken at one, two, four, six, 12 and 24 months of life. Risk factors were analyzed using multivariable linear regression.

RESULTS

The increment of mean weight-for-age and length-for-age were more evident for low birth weight when compared with adequate weight infants, especially during the first two months after birth. From this point onward it was observed a progressive mean growth deceleration in both indexes up to 12 months of life. All infants had similar weight and length growth patterns. However, adequate birth weight infants remained in an upper level. Socioeconomic variables explained 23% of variation for weight-for-age, followed by 4% for birth weight. Socioeconomic condition was also the factor mostly affecting length-for-age, explaining 28% of its variation, followed by birth weight, maternal height and diarrhea.

CONCLUSIONS

The study results suggest that interventions aiming to adequate growth should focus on prenatal care and social and environmental factors during childhood as a way of ensuring full expression of the genetic potential of this population.

Breast milk intake is not reduced more by the introduction of energy dense complementary food than by typical infant porridge

The effect of different energy densities of complementary foods on breast milk consumption is not well understood. In this study, we tested the hypothesis that provision of fortified spread (FS), a micronutrient fortified, energy-dense (22 kJ/g), ready-to-use food, to Malawian infants would not decrease their breast milk intake more than a traditional corn + soy blended flour (CSB). Forty-four healthy 6-mo-old infant and mother pairs were enrolled in a prospective, parallel group, investigator-blinded, randomized controlled complementary feeding trial. Infants were randomized to receive 25 g/d of FS, 50 g/d of FS, or 72 g/d of CSB. The primary outcome was the difference in breast milk intake after 1 mo of complementary feeding as measured by the dose-to-mother deuterium oxide dilution technique. Outcomes were compared using repeated measures ANOVA. A total of 41 mother-infant pairs completed the study. At enrollment, 88% of the infants had received corn porridge. At baseline, the infants consumed 129 +/- 18 g.kg body wt(-1) x d(-1) (mean +/- SD) of breast milk. After 1 mo of complementary feeding with 25 g/d FS, 50 g/d FS, or 72 g/d CSB, their breast milk consumption was 115 +/- 18 g.kg body wt(-1) x d(-1), a significant reduction; however, the effects of the complementary foods did not differ from one another (F-value model = 4.33, P = 0.0008 for effect of time and P = 0.69 for effect of type of food). The results suggest that complementary feeding of Malawian infants with FS has the same effect on their breast milk intake as complementary feeding with traditional CSB porridge.

Growth and change in blood haemoglobin concentration among underweight Malawian infants receiving fortified spreads for 12 weeks: a preliminary trial

OBJECTIVE

Fortified spreads (FSs) have proven effective in the rehabilitation of severely malnourished children. We examined acceptability, growth and change in blood haemoglobin (Hb) concentration among moderately underweight ambulatory infants given FS.

METHODS

This was a randomised, controlled, parallel-group, investigator-blind clinical trial in rural Malawi. Six- to 17-month-old underweight infants (weight for age < -2), whose weight was greater than 5.5 kg and weight-for-height z score greater than -3 received for 12 weeks at home 1 of 8 food supplementation schemes: nothing, 5, 25, 50, or 75 g/day milk-based FS or 25, 50, or 75 g/day soy-based FS. Outcome measures included change in weight, length and blood Hb concentration.

RESULTS

A total of 126 infants started and 125 completed the intervention. All infants accepted the spread well, and no intolerance was recorded. Average weight and length gains were higher among infants receiving daily 25 to 75 g FS than among those receiving only 0 to 5 g FS. Mean Hb concentration remained unchanged among unsupplemented controls but increased by 10 to 17 g/L among infants receiving any FS. All average gains were largest among infants receiving 50 g of FS daily: mean difference (95% confidence interval) in the 12-week gain between infants in 50 g milk-based FS group and the unsupplemented group was 290 g (range, -130 to 700 g), 0.9 cm (range, -0.3 to 2.2 cm), and 17 g/L (range, 0 to 34 g/L) for weight, length and blood Hb concentration, respectively. In soy- vs milk-based FS groups, average outcomes were comparable.

CONCLUSIONS

Supplementation with 25 to 75 g/day of highly fortified spread is feasible and may promote growth and alleviate anaemia among moderately malnourished infants. Further trials should test this hypothesis.

Sex differences in the relationships among weight gain, subcutaneous skinfold tissue and saltatory length growth spurts in infancy

As the mechanisms controlling the amount and timing of growth saltations are not well understood, the identification of physiologic coupling in weight and length growth are important for further understanding normal growth biology. Thirty-four healthy infants (13 males, 21 females) participated in a longitudinal growth study during the first year. Weekly weights and s.c. skinfolds (limb and trunk) were analyzed in a growth event-focused study. Coincident analysis tested the null hypothesis of chance concurrence between significant weight gain and saltatory length growth spurts. Logistic regression quantified this relationship and investigated the interaction between incremental weight gain and s.c. skinfolds on length growth spurts. The null hypothesis of random coincidence between weight gain and saltatory length growth was not supported. For girls, significant weight gain and length growth were coupled during the same week and length saltations were 42% more likely during the weeks of significant weight gain, with no interaction from s.c. skinfolds. For boys, length growth saltations were coupled to both previous and concomitant weight gain but were predicted only by previous weight gain, controlling for confounders. Boys were 68% more likely to grow in length the week following significant weight gain, and initial abdominal to suprailiac skinfold ratios conferred a 4-fold increased likelihood of length growth within the week, controlling for confounders. These data generate the hypothesis that a common growth signal cascade couples growth in weight and length/height with a time delay due to sex-specific biology, reflected in a s.c. fat fold interface.

Catch-up growth in Malawian babies, a longitudinal study of normal and low birthweight babies born in a malarious endemic area

INTRODUCTION

Infant growth has not been studied in developing countries in relation to maternal factors related to malaria in pregnancy and maternal illiteracy.

OBJECTIVE

To describe growth patterns in infants with low and normal birthweight and determine maternal risk factors for infant undernutrition.

METHODS

Babies born in a rural district of southern Malawi were recruited. An infant cohort was selected on the basis of low or normal birthweight. Weight and length were recorded at birth and at 4-weekly intervals until at 52 weeks after birth. Maternal characteristics at first antenatal attendance and delivery were obtained. Odds ratios in univariate analysis were adjusted for birthweight. Factors included in the multivariate regression included maternal illiteracy, season of birth, maternal iron deficiency and number of infant illness episodes.

RESULTS

Low birthweight infants were shorter and lighter throughout infancy than either normal birthweight or international reference values. At 12 months, placental or peripheral malaria at delivery (adjusted odds 1.8; 1.0, 3.1), number of infant illness episodes (AOR = 2.1; 1.2, 3.6) and maternal illiteracy (AOR = 2.7; 1.5, 4.9) were independently associated with low weight for age. Maternal short stature (AOR = 1.8; 1.1. 3.2), male sex (AOR = 2.4; 1.4, 4.1), number of infant illness episodes (AOR = 2.6; 1.5, 4.4), and birth in the rainy season (2.1; 1.2, 3.7) were independently associated with stunting. Placental or peripheral malaria at delivery (AOR = 2.2; 1.1, 4.4) and number of illness episodes (AOR = 2.2; 1.1, 4.5) were independently associated with thinness.

CONCLUSION

Malaria during pregnancy and maternal illiteracy are important maternal characteristics associated with infant undernutrition. Innovative health/literacy strategies are required to address malaria control in pregnancy in order to reduce the magnitude of its effects on infant undernutrition.