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Background: Early growth faltering accounts for one-third of child deaths, and adversely impacts the health and human capital of surviving children. Social as well as biological factors contribute to growth faltering, but their relative strength and interrelations in different contexts have not been fully described., Objective: The aim of this study was to use structural equation modelling to explore social and biological multidetermination of child height at age 2 y in longitudinal data from 4 birth cohort studies in low- and middle-income countries., Methods: We analyzed data from 13,824 participants in birth cohort studies in Brazil, India, the Philippines, and South Africa. We used exploratory structural equation models, with height-for-age at 24 mo as the outcome to derive factors, and path analysis to estimate relations among a wide set of social and biological variables common to the 4 sites., Results: The prevalence of stunting at 24 mo ranged from 14.0% in Brazil to 67.7% in the Philippines. Maternal height and birthweight were strongly predictive of height-for-age at 24 mo in all 4 sites (all P values <0.001). Three social-environmental factors, which we characterized as "child circumstances," "family socioeconomic status," and "community facilities," were identified in all sites. Each social-environmental factor was also strongly predictive of height-for-age at 24 mo (all P values <0.001), with some relations partly mediated through birthweight. The biological pathways accounted for 59% of the total explained variance and the social-environmental pathways accounted for 41%. The resulting path coefficients were broadly similar across the 4 sites., Conclusions: Early child growth faltering is determined by both biological and social factors. Maternal height, itself a marker of intergenerational deprivation, strongly influences child height at 2 y, including indirect effects through birthweight and social factors. However, concurrent social factors, many of which are modifiable, directly and indirectly contribute to child growth. This study highlights opportunities for interventions that address both biological and social determinants over the long and short term.

Background: Performance in intelligence tests tends to be higher among individuals breastfed as infants, but little is known about the association between breastfeeding and achieved schooling. We assessed the association of infant feeding with school achievement in five cohorts from low- and middle-income countries. Unlike high-income country settings where most previous studies come from, breastfeeding is not positively associated with socioeconomic position in our cohorts, thus reducing the likelihood of a spurious positive association., Methodology and Principal Findings: Participants included 10,082 young adults from five birth cohorts (Brazil, India, Guatemala, the Philippines, and South Africa). The exposures variables were whether the subject was ever breastfed, total duration of breastfeeding, and age at introduction of complementary foods. We adjusted the estimates for age at follow up, sex, maternal age, smoking during pregnancy, birthweight and socioeconomic position at birth. The key outcome was the highest grade achieved at school. In unadjusted analyses, the association between ever breastfeeding and schooling was positive in Brazil, inverse in the Philippines, and null in South Africa; in adjusted analyses, these associations were attenuated. In Brazil, schooling was highest among individuals breastfed for 3-12 months whereas in the Philippines duration of breastfeeding was inversely associated with schooling; and null associations were observed in South Africa and Guatemala. These associations were attenuated in adjusted models. Late introduction of solid foods was associated with lower schooling achievement in Brazil and South Africa., Conclusion: Measures of breastfeeding are not consistently related to schooling achievement in contemporary cohorts of young adults in lower and middle-income countries.

Objective: We examined associations of birth weight and weight gain in infancy and early childhood with type 2 diabetes (DM) risk in five cohorts from low- and middle-income countries., Research Design and Methods: Participants were 6,511 young adults from Brazil, Guatemala, India, the Philippines, and South Africa. Exposures were weight at birth, at 24 and 48 months, and adult weight, and conditional weight gain (CWG, deviation from expected weight gain) between these ages. Outcomes were adult fasting glucose, impaired fasting glucose or DM (IFG/DM), and insulin resistance homeostasis model assessment (IR-HOMA, three cohorts)., Results: Birth weight was inversely associated with adult glucose and risk of IFG/DM (odds ratio 0.91[95% CI 0.84-0.99] per SD). Weight at 24 and 48 months and CWG 0-24 and 24-48 months were unrelated to glucose and IFG/DM; however, CWG 48 months-adulthood was positively related to IFG/DM (1.32 [1.22-1.43] per SD). After adjusting for adult waist circumference, birth weight, weight at 24 and 48 months and CWG 0-24 months were inversely associated with glucose and IFG/DM. Birth weight was unrelated to IR-HOMA, whereas greater CWG at 0-24 and 24-48 months and 48 months-adulthood predicted higher IR-HOMA (all P < 0.001). After adjusting for adult waist circumference, birth weight was inversely related to IR-HOMA., Conclusions: Lower birth weight and accelerated weight gain after 48 months are risk factors for adult glucose intolerance. Accelerated weight gain between 0 and 24 months did not predict glucose intolerance but did predict higher insulin resistance.

Objective: To examine the association between household socio-economic status (SES) at birth and poor infant growth such as small for gestational age (SGA) and stunting across two different socio-cultural settings: South Africa and the Philippines., Design: Data were from two longitudinal birth cohorts, the Birth to Twenty (Bt20) study in South Africa and the Cebu Longitudinal Health and Nutrition Survey (CLHNS) in the Philippines., Subjects: Bt20 infants (n 2293 total; reduced to 758 (SGA), 450 (stunting 1 year) and 401 (stunting 2 years)) and CLHNS infants (n 2513 total; reduced to 2161 (SGA), 1820 (stunting 1 year) and 1710 (stunting 2 years))., Results: CLHNS infants were significantly more likely to be born SGA (20.9 v. 11.7 %) and be stunted at 1 year (32.6 v. 8.7 %) and 2 years (48.9 v. 21.1 %) compared with Bt20 infants. Logistic regression analyses showed that SES (index) was a significant predictor of stunting at 1 and 2 years of age in the CLHNS cohort. SES (index or individual variables) was not a significant predictor of SGA in either cohort, or of stunting in the Bt20 cohort. Maternal education, ownership of a television and toilet facilities were all independent predictors of stunting in the CLHNS cohort., Conclusions: The social and economic milieu within the Philippines appears to place CLHNS infants at greater risk of being born SGA and being stunted compared with Bt20 infants. The present research highlights the importance of investigating the individual SES variables that predict infantile growth faltering, to identify the key areas for context-specific policy development and intervention.