Lynnette M. Neufeld

Role of cash in conditional cash transfer programmes for child health, growth, and development: an analysis of Mexico's Oportunidades

BACKGROUND Many governments have implemented conditional cash transfer (CCT) programmes with the goal of improving options for poor families through interventions in health, nutrition, and education. Families enrolled in CCT programmes receive cash in exchange for complying with certain conditions: preventive health requirements and nutrition supplementation, education, and monitoring designed to improve health outcomes and promote positive behaviour change. Our aim was to disaggregate the effects of cash transfer from those of other programme components. METHODS In an intervention that began in 1998 in Mexico, low-income communities (n=506) were randomly assigned to be enrolled in a CCT programme (Oportunidades, formerly Progresa) immediately or 18 months later. In 2003, children (n=2449) aged 24-68 months who had been enrolled in the programme their entire lives were assessed for a wide variety of outcomes. We used linear and logistic regression to determine the effect size for each outcome that is associated with a doubling of cash transfers while controlling for a wide range of covariates, including measures of household socioeconomic status. FINDINGS A doubling of cash transfers was associated with higher height-for-age Z score (beta 0.20, 95% CI 0.09-0.30; p<0.0001), lower prevalence of stunting (-0.10, -0.16 to -0.05; p<0.0001), lower body-mass index for age percentile (-2.85, -5.54 to -0.15; p=0.04), and lower prevalence of being overweight (-0.08, -0.13 to -0.03; p=0.001). A doubling of cash transfers was also associated with children doing better on a scale of motor development, three scales of cognitive development, and with receptive language. INTERPRETATION Our results suggest that the cash transfer component of Oportunidades is associated with better outcomes in child health, growth, and development.

Effect of timing of umbilical cord clamping on iron status in Mexican infants: a randomised controlled trial

BACKGROUND Delayed clamping of the umbilical cord increases the infants iron endowment at birth and haemoglobin concentration at 2 months of age. We aimed to assess whether a 2-minute delay in the clamping of the umbilical cord of normal-weight, full-term infants improved iron and haematological status up to 6 months of age. METHODS 476 mother-infant pairs were recruited at a large obstetrics hospital in Mexico City, Mexico, randomly assigned to delayed clamping (2 min after delivery of the infants shoulders) or early clamping (around 10 s after delivery), and followed up until 6 months postpartum. Primary outcomes were infant haematological status and iron status at 6 months of age, and analysis was by intention-to-treat. This study is registered with ClinicalTrials.gov, number NCT00298051. FINDINGS 358 (75%) mother-infant pairs completed the trial. At 6 months of age, infants who had delayed clamping had significantly higher mean corpuscular volume (81.0 fL vs 79.5 fL 95% CI -2.5 to -0.6, p=0.001), ferritin (50.7 mug/L vs 34.4 mug/L 95% CI -30.7 to -1.9, p=0.0002), and total body iron. The effect of delayed clamping was significantly greater for infants born to mothers with low ferritin at delivery, breastfed infants not receiving iron-fortified milk or formula, and infants born with birthweight between 2500 g and 3000 g. A cord clamping delay of 2 minutes increased 6-month iron stores by about 27-47 mg. INTERPRETATION Delay in cord clamping of 2 minutes could help prevent iron deficiency from developing before 6 months of age, when iron-fortified complementary foods could be introduced.

10-year effect of Oportunidades, Mexico's conditional cash transfer programme, on child growth, cognition, language, and behaviour: a longitudinal follow-up study

BACKGROUND Mexicos conditional cash transfer programme, Oportunidades, was started to improve the lives of poor families through interventions in health, nutrition, and education. We investigated the effect of Oportunidades on children almost 10 years after the programme began. METHODS From April, 1998, to October, 1999, low-income communities were randomly assigned to be enrolled in Oportunidades immediately (early treatment, n=320) or 18 months later (late treatment, n=186). In 2007, when 1093 children receiving early treatment and 700 late treatment in these communities were aged 8-10 years, they were assessed for outcomes including physical growth, cognitive and language development, and socioemotional development. The primary objective was to investigate outcomes associated with an additional 18 months in the programme. We used cluster-adjusted t tests and multivariate regressions to compare effects of programme participation for height-for-age, body-mass index (BMI), and cognitive language and behavioural assessment scores in early versus late treatment groups. FINDINGS Early enrolment reduced behavioural problems for all children in the early versus late treatment group (mean behaviour problem score -0.09 [SD 0.97] vs 0.13 [1.03]; p=0.0024), but we identified no difference between groups for mean height-for-age Z scores (-1.12 [0.96] vs -1.14 [0.97]; p=0.88), BMI-for-age Z scores (0.14 [0.99] vs 0.17 [1.06]; p=0.58), or assessment scores for language (98.8 [13.8] vs 98.4 [14.6] p=0.90) or cognition (98.8 [12.9] vs 100.2 [13.2]; p=0.26). An additional 18 months of the programme before age 3 years for children aged 8-10 years whose mothers had no education resulted in improved child growth of about 1.5 cm assessed as height-for-age [corrected] Z score (beta 0.23 [0.023-0.44] p=0.029), independently of cash received. INTERPRETATION An additional 18 months in the Oportunidades programme has independent beneficial effects other than money, especially for women with no formal education. The money itself also has significant effects on most outcomes, adding to existing evidence for interventions in early childhood. FUNDING Mexican Ministry of Social Development and the National Institutes of Child Health and Human Development.

Hemoglobin measured by Hemocue and a reference method in venous and capillary blood: a validation study

OBJECTIVE To assess the comparability of hemoglobin concentration (Hb) in venous and capillary blood measured by Hemocue and an automated spectrophotometer (Celldyn) and to document the influence of type of blood (capillary or venous) and analysis method on anemia prevalence estimates. MATERIAL AND METHODS Between February and May 2000, capillary and venous samples were collected from 72 adults and children at Hospital del Niño Morelense (Morelos State Childrens Hospital) in Cuernavaca, Morelos, Mexico, and assessed for Hb using the Hemocue and Celldyn methods. Estimated Hb levels were compared using the concordance correlation coefficient and Students t test for paired data. The sensitivity and specificity for anemia diagnosis were estimated and compared between type of blood and method of assessment. RESULTS Capillary blood had higher Hb (+0.5 g/dl) than venous blood in adults and children, as did samples assessed by Celldyn compared to Hemocue (+0.3 g/dl). Specificity to detect anemia was adequate (> 0.90) but sensitivity was low for capillary blood assessed by Hemocue (< 0.80). CONCLUSIONS The difference in Hb between venous and capillary blood is likely related to biological variability. Hemoglobin concentration in capillary blood assessed by Hemocue provides an adequate estimation of population anemia prevalence but may result in excess false negative diagnoses among individuals. The results of this study stress the importance of sample collection technique, particularly for children. Method of analysis and sampling site need to be taken into consideration in field studies. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.

Dietary Associations of Household Food Insecurity among Children of Mexican Descent: Results of a Binational Study

BACKGROUND/OBJECTIVE Children of Mexican descent frequently experience household food insecurity both in the United States and Mexico. However, little is known about the associations of food insecurity with dietary intake. This study aimed to understand the level of perceived food insecurity and its association with dietary intake among children of Mexican descent residing in the United States and Mexico. DESIGN This cross-sectional study utilized data from a 2006 binational study of 5-year-old children of Mexican descent living in migrant communities in California and Mexico. METHODS In California, children were 301 participants from the Center for the Health Assessment of Mothers and Children of Salinas study, a longitudinal birth cohort in a Mexican immigrant community. Mexican children (n=301) were participants in the Proyecto Mariposa study, which was designed to capture a sample of women and their children living in Mexico who closely resembled the California sample, yet who never migrated to the United States. Household food insecurity was measured using the US Department of Agriculture Food Security Scale and dietary intake was assessed with food frequency questionnaires. Analysis of variance was used to examine unadjusted and adjusted differences in total energy, nutrient intake, and consumption of food groups by household food security status. RESULTS Approximately 39% of California mothers and 75% of Mexico mothers reported low or very low food security in the past 12 months (P<0.01). Children in the United States experiencing food insecurity consumed more fat, saturated fat, sweets, and fried snacks than children not experiencing food insecurity. In contrast, in Mexico food insecurity was associated with lower intake of total carbohydrates, dairy, and vitamin B-6. CONCLUSIONS Programs and policies addressing food insecurity in the United States and Mexico may need to take steps to address dietary intake among children in households experiencing food insecurity, possibly through education and programs to increase resources to obtain healthful foods.

Maternal Perceptions of Early Childhood Ideal Body Weight Differ among Mexican-Origin Mothers Residing in Mexico Compared to California

OBJECTIVE To assess maternal perceptions of childrens current and ideal body sizes, and the meaning of and factors contributing to overweight in infancy and early childhood among Mexican-origin mothers living in Mexico and in California. DESIGN A quali-quantitative study combining focus groups and a self-administered questionnaire. SUBJECTS/SETTING A purposive sample of 84 low-income, Mexican-origin mothers of 4- to 6-year-old children recruited between March 2006 and January 2008 from rural and urban communities in Mexico and California. STATISTICAL ANALYSES Bivariate, multivariate, and qualitative analyses of maternal perceptions of childrens actual and ideal body size supplemented by qualitative analyses of meaning of and factors contributing to childhood overweight/obesity. RESULTS Ideal child body size was considerably lower among Mexican-origin mothers living in California (3.86+/-0.56) than it was among mothers living in Mexico (4.32+/-0.83), and this difference was significant (P=0.001) after adjusting for sociodemographic covariates. Among mothers of overweight children, 82% of mothers in California were dissatisfied with their childs weight compared with 29% of mothers in Mexico (P=0.003). Focus-group results suggest that these differences in the perception of childrens ideal body size can be attributable to differences in body size norms among mothers and awareness of the negative effects of obesity that occur after migration to California. CONCLUSIONS Maternal perceptions of early childhood overweight appear to differ among Mexican-origin women living in Mexico and California. Recognition of the negative health consequences of obesity and identification of barriers to achieving weight control are important first steps toward childhood obesity prevention. Interventions directed at Mexican-origin mothers should focus on culturally acceptable ways of transmitting weight-control information.

Multiple micronutrient supplementation during early childhood increases child size at 2 y of age only among high compliers

BACKGROUND Micronutrient deficiencies are common, even in middle-income countries. OBJECTIVE The objectives were to determine whether multiple micronutrient (MM) supplementation from 3 to 24 mo of age improves growth and whether the effect is modified by MM supplementation during pregnancy. DESIGN We conducted a randomized, double-blind, controlled trial in central Mexico. Singleton live births (n = 650) from a prenatal MM trial were randomly assigned to receive either MM supplements (1-1.5 times the Recommended Dietary Allowance of vitamins A, B-6, B-12, and C; folic acid; iron; zinc; and other nutrients) or supplements containing similar amounts of iron and vitamin A (Fe-A) within the maternal supplementation groups (MM and iron only) 6 d/wk from 3 to 24 mo of age. Anthropometric measurements were obtained at 3 and 24 mo of age. RESULTS There was no effect of supplement group on child growth in intention-to-treat analyses. However, infants who consumed MM supplements regularly (greater than the median compliance of 79%) were 0.8 (95% CI: -0.4, 1.9) and 1.6 (95% CI: 0.4, 2.8) cm taller at 24 mo in the maternal MM and iron-only groups, respectively, than were those in the Fe-A group; these differences were 0.2 (95% CI: -1.0, 1.4) and -0.5 (95% CI: -1.7, 0.7) cm among those with compliance below the median. Mean body mass index (in kg/m(2)) was significantly higher in those exposed to iron only in utero and Fe-A during childhood (16.2) than in the other groups (15.8). CONCLUSIONS MM supplements increased the length of children who consumed them regularly from 3 to 24 mo. Strategies that promote compliance through effective delivery of micronutrient interventions are needed.

Parallel deficits in linear growth and mental development in low-income Mexican infants in the second year of life

OBJECTIVE To explore anthropometric indicators and mental development in very-low-income children in the second year of life. DESIGN Cross-sectional survey. SETTING Low-income areas (income <20th percentile) in semi-urban Mexico (defined as towns or cities with 2,500-50,000 inhabitants). SUBJECTS Eight hundred and ninety-six children aged 12.5-23.5 months surveyed from September to December 2001. METHODS Questionnaire survey and anthropometric survey of households. Multivariate regression models evaluated differences across age in anthropometry (height-for-age Z-score (HAZ) and weight-for-height Z-score) and cognitive function (Mental Development Index (MDI) of the Bayley Scales of Infant Development) while controlling for socio-economic and parental characteristics. RESULTS There was a significant decline in HAZ and in age-adjusted MDI score across the second year of life. Although the children showed MDI scores close to the mean, normed US values at 13-14 months, the scores were significantly lower than expected in older children (P < 0.0001), even after controlling for socio-economic status and parental characteristics. At 13-14 months, only 3% of children received scores below 70 (less than minus two standard deviations), whereas by 19-20 months, almost 17% of children were performing below this level. No socio-economic or parental characteristics were significant predictors of HAZ or MDI. CONCLUSIONS Parallel deficits are evident in both height-for-age and cognitive functioning during the second year of life in low-income Mexican infants. The consistency of these growth and development findings further stresses the need for targeted interventions to reduce the vulnerability of low-income Mexican children very early in life.

Expanding the Frontiers of Population Nutrition Research: New Questions, New Methods, and New Approaches

Nutrition research, ranging from molecular to population levels and all points along this spectrum, is exploring new frontiers as new technologies and societal changes create new possibilities and demands. This paper defines a set of frontiers at the population level that are being created by the increased societal recognition of the importance of nutrition; its connection to urgent health, social, and environmental problems; and the need for effective and sustainable solutions at the population level. The frontiers are defined in terms of why, what, who, and how we study at the population level and the disciplinary foundations for that research. The paper provides illustrations of research along some of these frontiers, an overarching framework for population nutrition research, and access to some of the literature from outside of nutrition that can enhance the intellectual coherence, practical utility, and societal benefit of population nutrition research. The frontiers defined in this paper build on earlier forward-looking efforts by the American Society for Nutrition and extend these efforts in significant ways. The American Society for Nutrition and its members can play pivotal roles in advancing these frontiers by addressing a number of well-recognized challenges associated with transdisciplinary and engaged research.

Rationale design methodology and sample characteristics for the Vietnam pre-conceptual micronutrient supplementation trial (PRECONCEPT): a randomized controlled study.

BackgroundLow birth weight and maternal anemia remain intractable problems in many developing countries. The adequacy of the current strategy of providing iron-folic acid (IFA) supplements only during pregnancy has been questioned given many women enter pregnancy with poor iron stores, the substantial micronutrient demand by maternal and fetal tissues, and programmatic issues related to timing and coverage of prenatal care. Weekly IFA supplementation for women of reproductive age (WRA) improves iron status and reduces the burden of anemia in the short term, but few studies have evaluated subsequent pregnancy and birth outcomes.The Preconcept trial aims to determine whether pre-pregnancy weekly IFA or multiple micronutrient (MM) supplementation will improve birth outcomes and maternal and infant iron status compared to the current practice of prenatal IFA supplementation only. This paper provides an overview of study design, methodology and sample characteristics from baseline survey data and key lessons learned.Methods/designWe have recruited 5011 WRA in a double-blind stratified randomized controlled trial in rural Vietnam and randomly assigned them to receive weekly supplements containing either: 1) 2800 μg folic acid 2) 60 mg iron and 2800 μg folic acid or 3) MM. Women who become pregnant receive daily IFA, and are being followed through pregnancy, delivery, and up to three months post-partum. Study outcomes include birth outcomes and maternal and infant iron status. Data are being collected on household characteristics, maternal diet and mental health, anthropometry, infant feeding practices, morbidity and compliance.DiscussionThe study is timely and responds to the WHO Global Expert Consultation which identified the need to evaluate the long term benefits of weekly IFA and MM supplementation in WRA. Findings will generate new information to help guide policy and programs designed to reduce the burden of anemia in women and children and improve maternal and child health outcomes in resource poor settings.Trial registrationNCT01665378