Laura E. Caulfield

Maternal and child undernutrition: global and regional exposures and health consequences

Maternal and child undernutrition is highly prevalent in low-income and middle-income countries, resulting in substantial increases in mortality and overall disease burden. In this paper, we present new analyses to estimate the effects of the risks related to measures of undernutrition, as well as to suboptimum breastfeeding practices on mortality and disease. We estimated that stunting, severe wasting, and intrauterine growth restriction together were responsible for 2·2 million deaths and 21% of disability-adjusted life-years (DALYs) for children younger than 5 years. Deficiencies of vitamin A and zinc were estimated to be responsible for 0·6 million and 0·4 million deaths, respectively, and a combined 9% of global childhood DALYs. Iron and iodine deficiencies resulted in few child deaths, and combined were responsible for about 0·2% of global childhood DALYs. Iron deficiency as a risk factor for maternal mortality added 115 000 deaths and 0·4% of global total DALYs. Suboptimum breastfeeding was estimated to be responsible for 1·4 million child deaths and 44 million DALYs (10% of DALYs in children younger than 5 years). In an analysis that accounted for co-exposure of these nutrition-related factors, they were together responsible for about 35% of child deaths and 11% of the total global disease burden. The high mortality and disease burden resulting from these nutrition-related factors make a compelling case for the urgent implementation of interventions to reduce their occurrence or ameliorate their consequences.

The associations of parity and maternal age with small-for-gestational-age preterm and neonatal and infant mortality: a meta-analysis.

BackgroundPrevious studies have reported on adverse neonatal outcomes associated with parity and maternal age. Many of these studies have relied on cross-sectional data, from which drawing causal inference is complex. We explore the associations between parity/maternal age and adverse neonatal outcomes using data from cohort studies conducted in low- and middle-income countries (LMIC).MethodsData from 14 cohort studies were included. Parity (nulliparous, parity 1-2, parity ≥3) and maternal age (<18 years, 18-<35 years, ≥35 years) categories were matched with each other to create exposure categories, with those who are parity 1-2 and age 18-<35 years as the reference. Outcomes included small-for-gestational-age (SGA), preterm, neonatal and infant mortality. Adjusted odds ratios (aOR) were calculated per study and meta-analyzed.ResultsNulliparous, age <18 year women, compared with women who were parity 1-2 and age 18-<35 years had the highest odds of SGA (pooled adjusted OR: 1.80), preterm (pooled aOR: 1.52), neonatal mortality (pooled aOR: 2.07), and infant mortality (pooled aOR: 1.49). Increased odds were also noted for SGA and neonatal mortality for nulliparous/age 18-<35 years, preterm, neonatal, and infant mortality for parity ≥3/age 18-<35 years, and preterm and neonatal mortality for parity ≥3/≥35 years.ConclusionsNulliparous women <18 years of age have the highest odds of adverse neonatal outcomes. Family planning has traditionally been the least successful in addressing young age as a risk factor; a renewed focus must be placed on finding effective interventions that delay age at first birth. Higher odds of adverse outcomes are also seen among parity ≥3 / age ≥35 mothers, suggesting that reproductive health interventions need to address the entirety of a woman’s reproductive period.FundingFunding was provided by the Bill & Melinda Gates Foundation (810-2054) by a grant to the US Fund for UNICEF to support the activities of the Child Health Epidemiology Reference Group.

Effectiveness of an educational intervention delivered through the health services to improve nutrition in young children: a cluster-randomised controlled trial

BACKGROUND Malnutrition is the underlying cause of half of child mortality. Many programmes attempt to remedy this issue but there is a lack of evidence on effective ways to decrease child malnutrition. METHODS We did a cluster-randomised trial of an educational intervention in a poor periurban area (ie, shanty town) of Peru. Guided by formative research, the intervention aimed to enhance the quality and coverage of existing nutrition education and to introduce an accreditation system in six government health facilities compared with six control facilities. The primary outcome measure was growth that was measured by weight, length, and Z scores for weight-for-age and length-for-age at age 18 months. Main secondary outcomes were the percentage of children receiving recommended feeding practices and the 24-h dietary intake of energy, iron, and zinc from complementary food at ages 6, 9, 12, and 18 months. Analysis was by intention to treat. FINDINGS We enrolled a birth cohort of 187 infants from the catchment areas of intervention centres and 190 from control areas. Caregivers in intervention areas were more likely to report receiving nutrition advice from the health service than were caregivers in control health facilities (16 [52%] of 31 vs 9 [24%] of 37, p=0.02). At 6 months more babies in intervention areas were fed nutrient-dense thick foods at lunch (a recommended complementary feeding practice) than were controls (48 [31%] of 157 vs 29 [20%] of 147; difference between groups 19 [11%], p=0.03). Fewer children in intervention areas failed to meet dietary requirements for energy (8 months: 30 [18%] of 170 vs 45 [27%] of 167, p=0.04; 12 months: 64 [38%] of 168 vs 82 [49%] of 167, p=0.043), iron (8 months: 155 [91%] of 170 vs 161 [96%] of 167, 9 months: 152 [93%] of 163 vs 165 [99%] of 166, p=0.047), and zinc (9 months: 125 [77%] of 163 vs 145 [87%] of 166, p=0.012) than did controls. Children in control areas were more likely to have stunted growth (ie, length for age less than 2 SD below the reference population median) at 18 months than children in intervention groups (26 [16%] of 165 vs 8 [5%] of 171; adjusted odds ratio 3.04 [95% CI 1.21-7.64]). Adjusted mean changes in weight gain, length gain, and Z scores were all significantly better in the intervention area than in the control area. INTERPRETATION Improvement of nutrition education delivered through health services can decrease the prevalence of stunted growth in childhood in areas where access to food is not a limiting factor.

Potential contribution of maternal zinc supplementation during pregnancy to maternal and child survival.

Mild-to-moderate zinc deficiency may be relatively common worldwide, but the public health importance of this degree of zinc deficiency is not well defined. The purpose of this review was to provide a conceptual framework for evaluating the public health importance of maternal zinc deficiency as it relates to fetal growth and development, complications of pregnancy, labor and delivery, and maternal and infant health. The mechanisms through which zinc deficiency could influence health outcomes are well described. The results of experimental studies conducted in animal models have motivated concern about the potential health effects of mild-to-moderate maternal zinc deficiency. Observational studies in human populations have produced strong associations between poor maternal zinc status and various indicators of poor pregnancy outcome, but supplementation trials have not produced strong, or even consistent results. Supplementation trials are needed to define the public health importance of maternal zinc deficiency worldwide.

National and regional estimates of term and preterm babies born small for gestational age in 138 low-income and middle-income countries in 2010

Summary Background National estimates for the numbers of babies born small for gestational age and the comorbidity with preterm birth are unavailable. We aimed to estimate the prevalence of term and preterm babies born small for gestational age (term-SGA and preterm-SGA), and the relation to low birthweight (<2500 g), in 138 countries of low and middle income in 2010. Methods Small for gestational age was defined as lower than the 10th centile for fetal growth from the 1991 US national reference population. Data from 22 birth cohort studies (14 low-income and middle-income countries) and from the WHO Global Survey on Maternal and Perinatal Health (23 countries) were used to model the prevalence of term-SGA births. Prevalence of preterm-SGA infants was calculated from meta-analyses. Findings In 2010, an estimated 32·4 million infants were born small for gestational age in low-income and middle-income countries (27% of livebirths), of whom 10·6 million infants were born at term and low birthweight. The prevalence of term-SGA babies ranged from 5·3% of livebirths in east Asia to 41·5% in south Asia, and the prevalence of preterm-SGA infants ranged from 1·2% in north Africa to 3·0% in southeast Asia. Of 18 million low-birthweight babies, 59% were term-SGA and 41% were preterm. Two-thirds of small-for-gestational-age infants were born in Asia (17·4 million in south Asia). Preterm-SGA babies totalled 2·8 million births in low-income and middle-income countries. Most small-for-gestational-age infants were born in India, Pakistan, Nigeria, and Bangladesh. Interpretation The burden of small-for-gestational-age births is very high in countries of low and middle income and is concentrated in south Asia. Implementation of effective interventions for babies born too small or too soon is an urgent priority to increase survival and reduce disability, stunting, and non-communicable diseases. Funding Bill & Melinda Gates Foundation by a grant to the US Fund for UNICEF to support the activities of the Child Health Epidemiology Reference Group (CHERG).

Interventions to Improve Intake of Complementary Foods by Infants 6 to 12 Months of Age in Developing Countries: Impact on Growth and on the Prevalence of Malnutrition and Potential Contribution to Child Survival

To evaluate programmatic efforts to improve dietary intake and growth in 6- to 12-month-old infants in developing countries, we reviewed the results of 5 efficacy trials and 16 programmes conducted in 14 countries. Efficacy trials were able to improve infant dietary intakes by 65 to 302 kcal/day and infant growth by 0.04 to 0.46 SD. Programmes reported large improvements in maternal knowledge and practices concerning infant feeding. Four programmes that provided information reported improvements in dietary intakes of 71 to 164 kcal/day and changes in growth of −0.08 to 0.87 SD. Despite variability in the results, the majority of research and programmatic efforts improved growth rates by 0.10 to 0.50 SD. in absolute terms, this range of improvement in growth would reduce prevalences of malnutrition (< −2 SD) at 12 months of age by 1% to 19% and could reduce deaths due to malnutrition by 2% to 13%, depending on the underlying prevalence of malnutrition in the community.

Arsenic in drinking water and lung cancer: A systematic review

Exposure to inorganic arsenic via drinking water is a growing public health concern. We conducted a systematic review of the literature examining the association between arsenic in drinking water and the risk of lung cancer in humans. Towards this aim, we searched electronic databases for articles published through April 2006. Nine ecological studies, two case-control studies, and six cohort studies were identified. The majority of the studies were conducted in areas of high arsenic exposure (100 microg/L) such as southwestern Taiwan, the Niigata Prefecture, Japan, and Northern Chile. Most of the studies reported markedly higher risks of lung cancer mortality or incidence in high arsenic areas compared to the general population or a low arsenic exposed reference group. The quality assessment showed that, among the studies identified, only four assessed arsenic exposure at the individual level. Further, only one of the ecological studies presented results adjusted for potential confounders other than age; of the cohort and case-control studies, only one-half adjusted for cigarette smoking status in the analysis. Despite these methodologic limitations, the consistent observation of strong, statistically significant associations from different study designs carried out in different regions provide support for a causal association between ingesting drinking water with high concentrations of arsenic and lung cancer. The lung cancer risk at lower exposure concentrations remains uncertain.

Cruciferous vegetable consumption and lung cancer risk: a systematic review.

Background: Cruciferous vegetables, rich in isothiocyanates, may protect against lung cancer. Glutathione S-transferases are important in metabolizing isothiocyanates; hence, variants in GST genes may modify the association between cruciferous vegetable intake and lung cancer. We carried out a systematic review to characterize the association between cruciferous vegetable intake and lung cancer risk, with an emphasis on the potential interaction between cruciferous vegetables and GSTM1 and GSTT1 gene variants. Methods: A search of the epidemiologic literature through December 2007 was conducted using 15 bibliographic databases without language restrictions. Thirty studies on the association between lung cancer and either total cruciferous vegetable consumption (6 cohort and 12 case-control studies) or specific cruciferous vegetables (1 cohort and 11 case-control studies) were included. Results: The risk for lung cancer among those in the highest category of total cruciferous vegetable intake was 22% lower in case-control studies [random-effects pooled odds ratio, 0.78; 95% confidence interval (95% CI), 0.70-0.88] and 17% lower in cohort studies (pooled relative risk, 0.83; 95% CI, 0.62-1.08) compared with those in the lowest category of intake. The strongest inverse association of total cruciferous vegetable intake with lung cancer risk was seen among individuals with GSTM1 and GSTT1 double null genotypes (odds ratio, 0.41; 95% CI, 0.26-0.65; P for interaction = 0.01). Conclusions: Epidemiologic evidence suggests that cruciferous vegetable intake may be weakly and inversely associated with lung cancer risk. Because of a gene-diet interaction, the strongest inverse association was among those with homozygous deletion for GSTM1 and GSTT1. (Cancer Epidemiol Biomarkers Prev 2009;18(1):184–95)

WIC-Based Interventions to Promote Breastfeeding Among African-American Women in Baltimore: Effects on Breastfeeding Initiation and Continuation

We evaluated the single and combined effects of introducing a motivational video and peer counseling into four matched WIC clinics on breastfeeding initiation and continuation at 7-10 days among African-American WIC participants. Of the 242 women with complete data, 48% initiated breastfeeding, but only 31% were still breastfeeding at 7-10 days. Initiation was associated with cesarean delivery, infant feeding instruction, no artificial milk discharge pack, attending the peer counselor only-intervention site, and intention to breastfeed. Continuation was influenced by infant feeding instruction, no artificial milk discharge pack, and intention to breastfeed. Overall, trends toward a positive impact of the breastfeeding promotion activities were evident but weak, and largely gone by 7-10 days postpartum.

Determinants of gestational weight gain outside the recommended ranges among black and white women

Objectives To identify factors influencing risk of gaining outside the Institute of Medicine recommendations for pregnancy weight gain, and to determine whether these factors differ by race. Methods Multivariate methods were used to identify risk factors for under- and over-gain among 2617 black and 1253 white women delivering at the Johns Hopkins Hospital during 1987–1989. Results Only 28.2% of black women and 32.5% of white women gained the recommended amounts of weight during pregnancy, Maternal pre-pregnancy body mass index (BMI), height, parity, education, smoking, hypertension, duration of pregnancy, and fetal sex influenced risk for under-gain or over-gain. Black women were 1.51 (95% confidence interval [CI] 1.23–1.85) times more likely to under-gain, but 0.89% (95% CI 0.74–1.08) times less likely to over-gain than white women. No interactions were found between any factor examined and BMI or race. Conclusion Only about one-third of women are gaining the recommended amounts of weight during pregnancy. Black women are at increased risk for gaining less weight than recommended, and selected maternal characteristics associated with race do not explain this difference. Further, risk factors for under- or over-gain do not differ between black and white women.