Susan M. Chang

Inequality in early childhood: Risk and protective factors for early child development

Inequality between and within populations has origins in adverse early experiences. Developmental neuroscience shows how early biological and psychosocial experiences affect brain development. We previously identified inadequate cognitive stimulation, stunting, iodine deficiency, and iron-deficiency anaemia as key risks that prevent millions of young children from attaining their developmental potential. Recent research emphasises the importance of these risks, strengthens the evidence for other risk factors including intrauterine growth restriction, malaria, lead exposure, HIV infection, maternal depression, institutionalisation, and exposure to societal violence, and identifies protective factors such as breastfeeding and maternal education. Evidence on risks resulting from prenatal maternal nutrition, maternal stress, and families affected with HIV is emerging. Interventions are urgently needed to reduce childrens risk exposure and to promote development in affected children. Our goal is to provide information to help the setting of priorities for early child development programmes and policies to benefit the worlds poorest children and reduce persistent inequalities.

Effects of early childhood psychosocial stimulation and nutritional supplementation on cognition and education in growth-stunted Jamaican children: prospective cohort study

Growth retardation affects about a third of children younger than age 5 years in developing countries and is associated with poor development. Previously, we did a trial of nutritional supplementation and psychosocial stimulation in stunted children aged 9-24 months. Non-stunted children were also assessed. Both types of intervention improved development. We now present the effects of early interventions on cognition and education in 103 of the 129 stunted children and compare them with 64 of the 84 non-stunted children now aged 17-18 years. We recorded no significant effects of nutritional supplementation. Compared with no intervention, stimulation resulted in higher full scale IQ scores (coefficient 0.38, 95% CI 0.06-0.71, p=0.02) and higher scores on the verbal subscale (0.37, 0.07-0.68, p=0.02), Peabody picture vocabulary test (7.84, 0.73-14.95, p=0.03), verbal analogies (0.26, 0.03-0.49, p=0.03), and reading tests (4.73, 1.31-8.14, p=0.007, and 2.7, 1.12-4.37, p=0.001). Overall, stunted non-stimulated participants had significantly poorer scores than the non-stunted group on 11 of 12 cognitive and educational tests. Stunting in early childhood is associated with cognitive and educational deficits in late adolescence, which are reduced by stimulation at a young age.

Labor market returns to an early childhood stimulation intervention in Jamaica

Help as hungry children helps young adults Supporters of early childhood interventions follow the rule “better early than late,” but so far theres been limited evidence that the rule applies to disadvantaged children in developing countries. Gertler et al. looked at the earnings of young adults in Jamaica, 20 years after, as toddlers, they were given 2 years of help from community health workers. The earnings of the treatment group caught up to those of a comparison group of well-fed children, but the control group of undernourished children that did not receive the health worker visits has lagged behind. Science, this issue p. 998 Encouraging greater mother-child interactions can compensate in the long term for poor nutrition. A substantial literature shows that U.S. early childhood interventions have important long-term economic benefits. However, there is little evidence on this question for developing countries. We report substantial effects on the earnings of participants in a randomized intervention conducted in 1986–1987 that gave psychosocial stimulation to growth-stunted Jamaican toddlers. The intervention consisted of weekly visits from community health workers over a 2-year period that taught parenting skills and encouraged mothers and children to interact in ways that develop cognitive and socioemotional skills. The authors reinterviewed 105 out of 129 study participants 20 years later and found that the intervention increased earnings by 25%, enough for them to catch up to the earnings of a nonstunted comparison group identified at baseline (65 out of 84 participants).

Early childhood stunting and later behaviour and school achievement.

BACKGROUND Stunting in early childhood is common in developing countries and is associated with poorer cognition and school achievement in later childhood. The effect of stunting on childrens behaviours is not as well established and is examined here. METHOD Children who were stunted at age 9 to 24 months and had taken part in a 2-year intervention programme of psychosocial stimulation with or without nutritional supplementation were reexamined at age 11-12 years and compared with non-stunted children from the same neighbourhoods. Their school and home behaviours were assessed using the Rutter Teacher and Parent Scales and school achievement was measured using the Wide Range Achievement Test (WRAT) and the Suffolk Reading Scales. RESULTS No significant intervention effects were found among the stunted groups. Thus data from the four intervention groups were aggregated for subsequent analyses, comparing all 116 stunted children with 80 non-stunted children. Controlling for social background variables, the stunted group had more conduct difficulties (p < .05) as rated by their parents. They also had significantly lower scores in arithmetic, spelling, word reading and reading comprehension than the non-stunted children (all p < .001). Conduct difficulties and hyperactivity were related to poorer school achievement. Controlling for the childrens IQ, the stunted childrens arithmetic scores remained significantly lower than those of the non-stunted children, but reading and spelling scores were not different. CONCLUSIONS Previously stunted children had more conduct difficulties at home, regardless of their social background, than non-stunted children. Their educational attainment was also poorer than non-stunted children and these results are suggestive of a specific arithmetic difficulty. Children with behaviour problems performed less well at school.

Early Childhood Stimulation Benefits Adult Competence and Reduces Violent Behavior

OBJECTIVE: An estimated 178 million children younger than 5 years in developing countries experience linear growth retardation and are unlikely to attain their developmental potential. We aimed to evaluate adult benefits from early childhood stimulation and/or nutritional supplementation in growth-retarded children. METHODS: In Kingston, Jamaica, 129 growth-retarded children aged 9 to 24 months took part in a 2-year trial of nutritional supplementation (1 kg milk-based formula per week) and/or psychosocial stimulation (weekly play sessions to improve mother-child interaction). We assessed IQ, educational attainment, and behavior at 22 years old in 105 participants. We used multivariate regressions, weighted to adjust for loss to follow-up, to determine treatment benefits. RESULTS: We found no significant benefits from supplementation. Participants who received stimulation reported less involvement in fights (odds ratio: 0.36 [95% confidence interval (CI) 0.12–1.06]) and in serious violent behavior (odds ratio: 0.33 [95% CI: 0.11–0.93]) than did participants with no stimulation. They also had higher adult IQ (coefficient: 6.3 [95% CI: 2.2–10.4]), higher educational attainment (achievement, grade level attained, and secondary examinations), better general knowledge, and fewer symptoms of depression and social inhibition. CONCLUSIONS: Early psychosocial intervention had wide-ranging benefits in adulthood that are likely to facilitate functioning in everyday life. The reductions in violent behavior are extremely important given the high levels of violence in many developing countries. The study provides critical evidence that early intervention can lead to gains in adult functioning.

Effects of psychosocial stimulation and dietary supplementation in early childhood on psychosocial functioning in late adolescence: follow-up of randomised controlled trial

Abstract Objective To determine whether dietary supplementation or psychosocial stimulation given to growth retarded (stunted) children age 9-24 months has long term benefits for their psychosocial functioning in late adolescence. Design Sixteen year follow-up study of a randomised controlled trial. Setting Poor neighbourhoods in Kingston, Jamaica. Participants Of 129 stunted children identified at age 9-24 months, 103 adolescents aged 17-18 were followed up. Intervention Supplementation with 1 kg milk based formula each week or psychosocial stimulation (weekly play sessions with mother and child), or both, for two years. Main outcome measures Anxiety, depression, self esteem, and antisocial behaviour assessed by questionnaires administered by interviewers; attention deficit, hyperactivity, and oppositional behaviour assessed by interviews with parents. Results Primary analysis indicated that participants who received stimulation had significantly different overall scores from those who did not (F = 2.047, P = 0.049). Supplementation had no significant effect (F = 1.505, P = 0.17). Participants who received stimulation reported less anxiety (mean difference - 2.81, 95% confidence interval - 5.02 to - 0.61), less depression (- 0.43, - 0.78 to - 0.07), and higher self esteem (1.55, 0.08 to 3.02) and parents reported fewer attention problems (- 3.34, - 6.48 to - 0.19). These differences are equivalent to effect sizes of 0.40-0.49 standard deviations. Conclusions Stimulation in early childhood has sustained benefits to stunted childrens emotional outcomes and attention.

Nutritional deficiencies and later behavioural development

The literature on the long-term effects of nutritional deficiencies in early life is reviewed. The severity and duration of the deficiency, the stage of the childrens development, the biological condition of the children and the socio-cultural context may all modify the effect. There is substantial evidence that reduced breast-feeding, small-for-gestational-age birth weight, Fe and I deficiency, and protein-energy malnutrition (PEM) are associated with long-term deficits in cognition and school achievement. However, all these conditions are associated with poverty and poor health, which may account for the association. It is difficult to establish that the long-term relationship is causal, as it requires a randomized treatment trial with long-term follow-up. Such studies are only available for I deficiency in utero and early childhood PEM. Results from these studies indicate that I deficiency has a long-term effect and PEM probably has a long-term effect.

The effect of psychosocial stimulation on cognition and behaviour at 6 years in a cohort of term, low‐birthweight Jamaican children

Aim  The aim of this study was to determine whether psychosocial stimulation up to the age of 2 years benefits cognition and behaviour at age 6 years in low‐birthweight, term‐born (LBW‐T) children (gestational age ≥37wk, birthweight <2500g), and to compare LBW‐T and normal‐birthweight (NBW) children.

Nutrition, anaemia, geohelminth infection and school achievement in rural Jamaican primary school children

Objective: To determine whether nutritional status, anaemia and geohelminth infections were related to school achievement and attendance in Jamaican children.Design: A cross-sectional study using a randomly selected sample.Subjects: Eight hundred children aged 9–13 y randomly selected from those enrolled in grade 5 in 16 primary schools in rural Jamaica.Results: The mean height-for-age of the children was −0.37 z-score±1.0 s.d. with 4.9% having heights-for-age <−2 s.d. of the NCHS references. Anaemia (Hb<11 ;g/dl) was present in 14.7% of the children, 38.3% were infected with Trichuris trichiura and 19.4% with Ascaris lumbricoides. Achievement levels on the Wide Range Achievement Test were low, with children performing at grade 3 level. In multilevel analyses, controlling for socioeconomic status, children with Trichuris infections had lower achievement levels than uninfected children in spelling, reading and arithmetic (P<0.05). Children with Ascaris infections had lower scores in spelling and reading (P<0.05) Height-for-age (P<0.01) was positively associated with performance in arithmetic. Ascaris infection (P<0.001) and anaemia (P<0.01) predicted poorer school attendance.Conclusion: Despite mild levels, undernutrition and geohelminth infections were associated with achievement, suggesting that efforts to increase school achievement levels in developing countries should include strategies to improve the health and nutritional status of children.Sponsorship: Funding was provided by the Commonwealth Caribbean Medical Research Council and the Inter-American Development Bank.

The association between early childhood stunting and weight status in late adolescence

Background:Cross-sectional studies have shown associations between stunting and overweight; however, there are few prospective studies of stunted children.Objectives:To determine whether stunting before age 2 years is associated with overweight and central adiposity at 17–18 years and whether growth in height among stunted children predicts body mass index (BMI) in late adolescence.Design:Prospective cohort study.Participants:One-hundred and three participants stunted by age 2 years and 64 non-stunted participants (78% of participants enrolled in childhood). Participants were measured in early childhood and at ages 7, 11 and 17 years.Results:Stunted subjects remained shorter and had lower BMIs, smaller skinfolds and circumferences than non-stunted subjects. Overweight (BMI ⩾25 m2) was not significantly different among stunted and non-stunted male subjects (5.2 and 12.5%) but non-stunted female subjects were more likely to be overweight than those who experienced early childhood stunting (11.1 and 34.4%, P=0.013). Centralization of fat (waist to hip ratio (WHR), subscapular/triceps skinfold ratio (SSF/TSF)) did not differ between stunted and non-stunted groups (mean WHR 0.77 and mean SSF/TSF 1.18 in both groups). Stunted subjects with greater increases in height-for-age for the intervals 3–7 and 7–11 years had higher BMI at age 17 years (P=0.04 and P=0.001, respectively).Conclusion:Participants stunted by age 2 years were less likely to be overweight than those who were never stunted. This suggests that cross-sectional studies of the association between stunting and overweight may be misleading. Among stunted children, greater linear growth during mid- to late childhood was associated with greater BMI at age 17 years.