S Grantham-McGregor Centre for Health and Development, Institute of Child Health, University College London Child development in developing countries

The Lancet series: The development of children <5 yrs in developing countries (Grantham-McGregor et al 2007, Walker et al 2007,P Engle et al 2007) International Child Development Steering Group: S Grantham-McGregor, P Engle, M Black, J Meeks Gardner, B Lozoff, T Wachs, S Walker, Paper 1&2, Y B Cheung, S Cueto, P Glewwe, Richter, B Strupp, J Meeks Gardner, GA Wasserman, E Pollitt, JA Carter 1.The size of the problem 2.The causes

Overall Aims of Lancet Series To increase awareness of the problem of poor development in early childhood in low resource countries. To make the promotion of optimal child development an international priority. Bring together academics from many different disciplines from universities, UN agencies and NGOs to develop a consensus for action.

Aims of paper Estimate the size of the problem Identify the location of affected children Estimate cost and consequences Factors causing poor development

Why focus on early childhood?  Brain development most rapid and vulnerable from conception to 5 years  Insults and interventions can have lasting effects  Interventions are more cost effective than at other ages  Cognitive ability & behaviour on entry school progress

Sensory- motor Cognitive- language Social- emotional Domains of Child Development

Major problem with estimating numbers of affected children Insufficient data on early cognitive ability for most developing countries to estimate prevalence

Need to use risk factors as indicators of poor child development to assess prevalence 1. Stunting (<-2SD) 2. Poverty<$1 per day ( adjusted for purchasing power by country, World Bank 2005)

Requirements of indicators Standardised measures across countries Global data available Relevant in most countries Consistently related to poor child development and school achievement in developing countries ?

Stunting in children > 28 studies X-sectional associations between stunting & poor cognition or school achievement

Longitudinal data essential Jamaica Walker South African Richter, Norris Phillipines Cebu study Uganda data Family Life Study Brazil Victora, Barros, Damiani, Lima, Gigante, Horta Peru Berkman, Lescano Guatemala Martorell

Cognitive or schooling deficits associated with moderate stunting <3yrs in 7 longitudinal studies Philippines S Africa Indonesia Brazil Peru Jamaica Guatemala 7yrs 9yrs 17-18yrs18yrs 15yrs 18-25yrs SD scores

Reasonable to use stunting as an indicator of poor child development Conclusion

Poverty <1 per day >60 X-sectional studies showed associations with wealth and school achievement or cognition

Later cognitive deficits associated with being in the lowest wealth quintile <3yrs in 5 longitudinal studies (SD scores) Philippines Indonesia S Africa Brazil^ Guatemala* ^Grades attained *boys 15yrs7yrs 18yrs 18-26yrs

Reasonable to use poverty as an indicator of poor child development Conclusion

Millions of children < 5y not fulfilling their potential in development (WHO, 2006; UNICEF 2006) Stunted Poverty Disadvantaged 156m 126m 219m (39% of children <5y) Stunted + Poverty not stunted

% of disadvantaged children <5yrs by region

Limitations Other risk factors not included Cut off for poverty uncertain Estimate for numbers of children based on poverty rates for total population Underestimate

1.Deficit in grades attained (Brazil) 2. Deficit in learning per grade (Phillipines, Jamaica) 3. Estimate total deficit (1+2) 4. Using estimate of 9% loss in income per grade (53 countries Psacharopoulos 2004, Duflo 2001) 20 % loss of yearly adult income Loss of yearly adult income

Deficit in grades attained Deficit in learning per grade % loss of yearly adult income Mean % Stunted % Poor0.71???5.9 Stunted & poor

Conclusion Loss of children’s potential is an enormous problem affecting >200million It has economic and social costs both to individual and nations

Risk factors affecting child development in low resource countries

Selection criteria Modifiable by interventions or public policy Affect large number of children less than 5 years in developing countries Risks with little information from developing countries excluded

Four main risks  Chronic undernutrition leading to stunting  Iodine deficiency  Iron deficiency anemia (IDA) Inadequate cognitive stimulation

Deficits at 17 yrs in Jamaican children stunted before 2 yrs IQ, vocabulary, cognition school achievement /drop out fine motor depression, anxiety, attention deficit, self esteem, hyperactive, oppositional Walker et al 2005, 2006

Inadequate cognitive stimulation or learning opportunities A biological insult

Mean Corticosterone Levels Pre & Post Stress in Non- handled, Handled and Maternally-separated Rats Plotsky & Meaney 1993 µg/dl Pre-stress Time (min) (n= 8 per group)

Intervention studies 15 of 16 intervention studies providing cognitive stimulation show benefits to development Centre based or home based: Effect size SD Lancet paper2

Effects of visiting frequency in disadvantaged children DQ Powell & Grantham-McGregor, 1989 fortnightly monthly no visits Pre-testPost-test weekly

McKay et al, 1979 Cognitive ability Cognitive ability at 7 years by duration of center based intervention; Colombia Periods of intervention

Interventions with stunted children DQ non-stuntedcontrol Grantham-McGregor et al, 1991 both Rxs supplemented stimulated

Sustained: Benefits at Years From Early Childhood Stimulation in Stunted Children Standard scores P value Walker et al, 2005 ********** *** *** nsnsnsns *p<.1; **p<.05, ***p<.01

Sustained: Benefits at years from stimulation in early childhood in stunted children Standard scores ******ns**nsns* P value Walker et al unpublished *p<.1; **p<.05

Consistent concurrent benefits to child’s DQ Consistent concurrent benefits to child’s DQ Benefits greater in : Benefits greater in : more intense, longer, include nutrition Sustainable cognitive,education and mental health benefits at 17-18yrs Sustainable cognitive,education and mental health benefits at 17-18yrs Summary of stimulation studies

Conclusion: Good evidence for 4 main risks  Chronic undernutrition leading to stunting  Iodine deficiency  Iron deficiency  Inadequate cognitive stimulation

Other risk factors Risk factors with consistent epidemiological evidence showing association with development Lack of interventions with evaluation of effectiveness

Other risks identified Small for gestational age Malaria Maternal depression Exposure to violence Exposure to environmental toxins

Multiple risks in early childhood and achievement scores in adolescence Gorman and Pollitt, 1996 Risk factors

Mean Developmental Quotients on Griffiths Test DQ Age months Urban middle class n=78 Urban poor n=268 (Walker et al)

Poverty Poor care and home stimulation Maternal stress/ depression Low education Poor cognitive, socio-emotional development Stunting & wasting, iodine & iron deficiency, diarrhoea, infections Poor school achievement Poor sanitation, Food insecurity Poor hygiene, feeding practices, care-seeking

national economy

Countries with highest % of children < 5y who are stunted in Latin America & the Caribbean (UNICEF 2006) %

Types of evidence 1.Randomised trials and intervention studies 2.Prospective cohort studies 3.Associational studies (with control for confounders)

Vocabulary scores by SES quartiles in 36 to 72 month old children Equador Paxson and Shady 2005 age in months

Why health services? Only service accessing children in first 3 years Already has an infrastructure Development an integral part of health Poor health & nutrition poor development Mothers enjoy and can facilitate other activities We cannot wait for new services

Why psychosocial stimulation interventions? Malnourished children do not catch up with nutrition aloneMalnourished children do not catch up with nutrition alone Stimulation changes brain function in animalsStimulation changes brain function in animals Adoption studies show vast improvementAdoption studies show vast improvement In USA disadvantaged children have shown sustained benefitsIn USA disadvantaged children have shown sustained benefits

IQ scores of stunted and non-stunted Jamaican children from age 9-24 mo to 18 y Non-stunted Stunted Griffiths on Enrollment (9-24 mo) Griffiths (33-48 mo) Stanford- Binet (7-8 y) WISC-R (11-12 y) WAIS (17-18 y) SD score Walker et al 2005

7 longitudinal studies of stunting <3yrs & later function Country Follow-up age Outcome Indonesia 7 cognitive test S Africa 7 cognitive test Peru 9 IQ Philippines 15 schooling Jamaica schooling, IQ Brazil 18 attained grades Guatemala schooling, IQ