Ines Gonzalez-Casanova

Physical activity during the school day in public primary schools in Mexico City

OBJECTIVE To quantify the physical activity (PA) of students and describe the school environment surrounding PA. MATERIAL AND METHODS Between November 2005 and March 2006, in Mexico City, we conducted quantitative and qualitative observations to describe the PA and the school context. RESULTS Recess and physical education class (PE) were the only opportunities to participate in PA. PE occurred one time per week with a duration of 39.8+/-10.6 minutes which is less than national and international recommendations. Students participated in moderate-to-vigorous PA 29.2+/-17.8% of PE. The dynamics of PE did not promote the inclusion of all students or PA. During recess there was overcrowding of the school patio and no equipment for PA or organization of PA. DISCUSSION The PA of students in public schools in Mexico City can be improved by increasing the quantity and quality of PE and increasing opportunities for activity during recess.

The dual burden of malnutrition in Colombia

BACKGROUND Almost all nutrition policies in Colombia currently focus on either undernutrition or obesity, with the predominant emphasis on undernutrition. It is crucial to assess the prevalence of the dual burden of malnutrition in Colombia to better target programs and policies. OBJECTIVE The aim was to estimate the national prevalence of the dual burden of malnutrition in Colombia at the individual and household levels in children aged <5 y, school-age children, adolescents, and adults. DESIGN This was a cross-sectional analysis from the 2010 Colombian Demographic and Health Survey and the National Nutritional Survey that included 17,696 children aged <5 y, 25,508 school-aged children, 28,328 adolescents, 89,164 adults, and 10,487 households with mothers and children aged <5 y. The dual burden of malnutrition was defined as the coexistence of overweight and stunting or anemia in the same person or household. RESULTS In Colombia, low to high prevalences of overweight and obesity (3.4-51.2%) coexist with moderate to high prevalences of anemia (8.1-27.5%) and stunting (13.2%). The observed prevalence of the dual burden was lower than expected. Approximately 5% of households had at least one stunted child aged <5 y and an overweight mother compared with an expected prevalence of 6.9% (P < 0.001). Among school-aged children, 0.1% were classified as stunted and obese and 1.4% were both anemic and overweight compared with expected prevalences of 0.5% (P < 0.001) and 1.5% (P = 0.037), respectively. Among 13- to 49-y-old women, 3.4% had anemia and were overweight compared with an expected prevalence of 3.5% (P = 0.038). CONCLUSIONS National estimates of the dual burden of malnutrition in Colombia are lower than expected. Despite the independence of the occurrence of these conditions, the fact that the dual burden coexists at the national, household, and intraindividual levels suggests that public policies should address both conditions through multiple strategies. It is imperative to evaluate the current nutrition policies to inform malnutrition prevention efforts in Colombia and to share lessons with other countries at a similar stage of nutritional transition.

Comparing three body mass index classification systems to assess overweight and obesity in children and adolescents

OBJECTIVE To compare the International Obesity Task Force (IOTF) 2005, Centers for Disease Control and Prevention (CDC) 2000, and World Health Organization (WHO) 2007 body mass index (BMI) classification systems in terms of prevalence estimation and association with demographic factors. METHODS The 18 265 children and adolescents ages 5 to 18 years (mean = 11.2 years, standard deviation = 3.9 years) in the nationally representative Colombian National Nutrition Survey of 2005 were classified as overweight or obese according to IOTF, CDC, and WHO criteria. Prevalence estimates were compared according to each system and associations with age, sex, socioeconomic status, and population density were tested. RESULTS Prevalence estimates of combined overweight and obesity differed by system (males: IOTF = 8.5%, CDC = 10.8%, WHO = 14.1%; females: IOTF = 14.6%, CDC = 13.8%, WHO = 17.1%; P < 0.001). The association between combined overweight and obesity and age and sex varied by system. The odds of having overweight and obesity in children (5 to 10 years) compared with adolescents (11 to 18 years) were: IOTF, odds ratio (OR) = 0.87 and 95% confidence interval (CI) = 0.77-0.98; CDC, OR = 1.27 and CI = 1.14-1.42; WHO, OR = 1.21 and CI = 1.08-1.35. The values for females compared with males were: IOTF, OR = 1.84 and CI = 1.6-2.10; CDC, OR = 1.33 and CI = 1.17-1.51; WHO, OR = 1.25 and CI = 1.12-1.41. CONCLUSIONS There is a lack of consistency among the three main international systems in assessing overweight and obesity in children and adolescents. Appreciably different estimates of prevalence and associations with age and sex are obtained depending on which system is used. Future studies should assess how well each system reflects valid measures of body composition.

Micronutrient Intakes among Women of Reproductive Age in Vietnam

Background Micronutrient deficiencies are a public health concern worldwide negatively affecting maternal and child health outcomes. The primary underlying causes of micronutrient deficiencies are insufficient intake and poor bioavailability of micronutrients. However, reliable data on micronutrient intakes are sparse. The objectives of this study were to identify the key local food sources providing the majority of micronutrients and assess the adequacy and determinants of micronutrient intakes. Methods The study used data from a survey of 4,983 rural women of reproductive age (WRA) participating in a preconception micronutrient supplementation trial in Vietnam. Micronutrient intakes were assessed using a validated 107-item semi-quantitative food-frequency questionnaire. Multivariate linear and logistic regression analyses were used to examine the association between socioeconomic status and micronutrient intakes. Results Starchy staples were the main source of iron and zinc (37% and 54%, respectively) with only a small proportion from meat (10% and 18%, respectively). The primary source of folate and vitamin A were vegetables; vitamin B12 came from meat and eggs. The proportion of the population with intakes below the estimated average requirement was 25% for iron, 16% for zinc, 54% for folate, 64% for vitamin B12 and 27% for vitamin A. Socioeconomic status was the main determinant of micronutrient intakes. WRA in the highest quintile consumed 26% more iron, 19% more zinc, 36% more folate, 82% more vitamin B12 and 47% more vitamin A compared to those in the lowest quintile. Women in the upper quintiles of SES were more likely to obtain nutrients from more nutritious and higher bioavailable foods than those in the lowest quintile. Conclusions Underprivileged women were at increased risk for insufficient micronutrient intakes due to poor diet quality. Targeted efforts to promote the consumption of local nutrient rich foods along with educational programs and social development are needed.

Neither Preconceptional Weekly Multiple Micronutrient nor Iron–Folic Acid Supplements Affect Birth Size and Gestational Age Compared with a Folic Acid Supplement Alone in Rural Vietnamese Women: A Randomized Controlled Trial

BACKGROUND Maternal nutritional status before and during early pregnancy plays a critical role in fetal growth and development. The benefits of periconception folic acid (FA) supplementation in the prevention of neural tube defects is well recognized, but the evidence for preconception micronutrient interventions for improving pregnancy outcomes is limited. OBJECTIVE This study aimed to evaluate whether preconception supplementation with weekly iron and folic acid (IFA) or multiple micronutrients (MMs) improves birth outcomes compared with FA alone. METHODS We recruited 5011 women of reproductive age in a double-blind, randomized controlled trial in Vietnam and provided weekly supplements containing either 2800 μg FA, 60 mg Fe and 2800 μg FA (IFA), or the same amount of FA and iron plus other MMs until they conceived (n = 1813). All pregnant women received daily IFA through delivery, and were followed up for birth outcomes, including birth weight, gestational age, preterm delivery and small for gestational age (SGA). Group comparisons were done with the use of ANOVA or chi-square tests for both intention-to-treat (n = 1599) and per-protocol analyses (women consumed supplements ≥26 wk before conception; n = 824). Effect modification by baseline underweight or anemia status was tested with the use of generalized linear models. RESULTS The mean age of the women was 26 y, 30% were underweight, and <10% were nulliparous. The groups were similar for most baseline characteristics. The mean ± SD duration of the preconception intervention was 33 ± 25 wk and compliance was high (>90%). Infants born to the 3 groups of women did not differ (P ≥ 0.05) on mean ± SD birth weight (3076.8 ± 444.5 g) or gestational age (39.2 ± 2.0 wk), or prevalence of SGA (12%), low birth weight (5%) and preterm delivery (10%). There were no significant differences in women who consumed supplements ≥26 wk before conception or by baseline underweight or anemia. CONCLUSION Weekly supplementation with MMs or IFA before conception did not affect birth outcomes compared with FA in rural Vietnamese women. The trial was registered at clinicaltrials.gov as NCT01665378.

Prenatal Supplementation with Docosahexaenoic Acid Has No Effect on Growth through 60 Months of Age

BACKGROUND Prenatal supplementation with docosahexaenoic acid (DHA) has been shown to increase birth size, but it is unclear whether these differences translate into improved postnatal growth. OBJECTIVE We assessed the effect of prenatal supplementation with DHA on offspring weight, length, and body mass index (BMI) through 60 mo of age. METHODS We examined growth patterns (height, weight, and BMI) in a cohort of 802 Mexican children whose mothers participated in a randomized, controlled trial of daily supplementation with 400 mg/d of DHA or a placebo from week 18-22 of gestation through delivery, with the use of a longitudinal multilevel model of growth. RESULTS Overall, means ± SDs of height-, weight-, and BMI-for-age z scores relative to WHO growth standards at 60 mo were -0.49 ± 0.91, -1.15 ± 1.07 and 0.13 ± 1.11, respectively. There were no significant differences by treatment group (all P > 0.05) for height, weight, or BMI at any age through 60 mo. Similarly, DHA did not affect the average growth or the trajectories for these measures through 60 mo. CONCLUSION Prenatal DHA supplementation did not affect height, weight, or BMI through 60 mo of age. This trial was registered at clinicaltrials.gov as NCT00646360.

Impact of Preconception Micronutrient Supplementation on Anemia and Iron Status during Pregnancy and Postpartum: A Randomized Controlled Trial in Rural Vietnam

Objective Preconception micronutrient interventions may be a promising approach to reduce anemia and iron deficiency during pregnancy, but currently we have limited data to inform policies. We evaluated whether providing additional pre-pregnancy weekly iron-folic acid (IFA) or multiple micronutrient (MM) supplements compared to only folic acid (FA) improves iron status and anemia during pregnancy and early postpartum. Methods We conducted a double blind randomized controlled trial in which 5011 Vietnamese women were provided with weekly supplements containing either only 2800 μg FA (control group), IFA (60 mg Fe and 2800 μg FA) or MM (15 micronutrients with similar amounts of IFA). All women who became pregnant (n = 1813) in each of the 3 groups received daily IFA (60 mg Fe and 400 μg FA) through delivery. Hematological indicators were assessed at baseline (pre-pregnancy), during pregnancy, 3 months post-partum, and in cord blood. Adjusted generalized linear models were applied to examine the impact of preconception supplementation on anemia and iron stores, using both intention to treat and per protocol analyses (women consumed supplements ≥ 26 weeks before conception). Results At baseline, 20% of women were anemic, but only 14% had low iron stores (ferritin <30 μg/L) and 3% had iron deficiency (ferritin <12 μg/L). The groups were balanced for baseline characteristics. Anemia prevalence increased during pregnancy and post-partum but was similar among intervention groups. In intention to treat analyses, prenatal ferritin was significantly higher among women receiving MM (geometric mean (μg/L) [95% CI]: 93.6 [89.3–98.2]) and IFA (91.9 [87.6–96.3]) compared to control (85.3 [81.5–89.2]). In per protocol analyses, women receiving MM or IFA had higher ferritin 3 months postpartum (MM 118.2 [109.3–127.8]), IFA 117.8 [108.7–127.7] vs control 101.5 [94.0–109.7]) and gave birth to infants with greater iron stores (MM 184.3 [176.1–192.9]), IFA 189.9 [181.6–198.3] vs control 175.1 [167.9–182.6]). Conclusion Preconception supplementation with MM or IFA resulted in modest increases in maternal and infant iron stores but did not impact anemia. Further research is needed to characterize the etiology of anemia in this population and identify effective interventions for reducing prenatal anemia. Trial Registration ClinicalTrials.Gov NCT01665378

Mid-Upper-Arm and Calf Circumferences are Useful Predictors of Underweight in Women of Reproductive Age in Northern Vietnam

Background Mid-upper-arm circumference (MUAC) and calf circumference (CC) are correlated with body mass index (BMI) in adults and may be useful for screening women with underweight (BMI < 18.5 kg/m2). However, there is no consensus on appropriate MUAC and CC cutoff points in diverse populations, especially in women of reproductive age. Objective To assess the accuracy of different MUAC and CC cutoff points to screen for underweight and to identify the most appropriate cutoff points in a sample of women of reproductive age from rural northern Vietnam. Methods Anthropometric measurements (weight, height, MUAC, CC, and triceps and subscapular skinfold thicknesses) were obtained for 4,981 women of reproductive age who participated in a micronutrient intervention trial (PRECONCEPT) in Thái Nguyên Province, Viet- nam. Receiver operating characteristic (ROC) analysis was used to evaluate different cutoff values of MUAC and CC and identify the most appropriate cutoff values to predict underweight. Results The overall prevalence of underweight was 32%. The MUAC value of 23.5 cm and the CC value of 31 cm were identified as the best cutoffs based on low misclassification (16% for MUAC and 21% for CC) and good balance of sensitivity (89% and 85%, respectively) and specificity (71% and 67%, respectively. The ROC curves were similar across different ethnic groups, with the area under the curve (AUC) values reaching 0.89 to 0.93 for MUAC and 0.83 to 0.89 for CC. Conclusions MUAC and CC perform adequately in screening for underweight in women. The utility of these measurements in predicting functional outcomes should be examined.

Patterns of Fetal Growth Based on Ultrasound Measurement and its Relationship with Small for Gestational Age at Birth in Rural Vietnam.

BACKGROUND Small for gestational age (SGA) is a global health problem. Identifying the timing of fetal growth faltering is critical for developing preventive interventions. We aim to describe patterns of fetal growth and to predict SGA at birth using fetal ultrasound measurements. METHODS We studied 1412 pregnant women enrolled in a randomised-controlled trial evaluating maternal micronutrient supplementation in Thai Nguyen province, Vietnam. Ultrasound examinations included biparietal diameter (BPD), head circumference (HC) and abdominal circumference (AC), and femur length (FL). Measures were assessed using the new international fetal growth standards (INTERGROWTH-21st Project). Generalised linear mixed logit regression models were used to examine the association between ultrasound measures and SGA at birth. RESULTS Overall fetal growth restriction began in early pregnancy and continued through delivery, but the timing of growth faltering varied by measure: it began by 20 weeks for HC, BPD and AC, earlier as compared to FL growth that started >30 weeks. SGA infants had significantly lower mean fetal growth parameters as early as 14 weeks. Ultrasound measures below the 10th percentile were associated with a two to four times higher risk of SGA at birth compared to fetuses greater than the 50th percentile, with the largest odds ratios for AC (OR 3.9, 95% confidence interval (CI) 2.7, 5.7). CONCLUSIONS Fetal growth faltering by ultrasound begins in early gestation among rural Vietnamese populations; these patterns clearly identified those to be born SGA. Efforts to prevent fetal growth faltering must begin early in pregnancy and perhaps even before pregnancy.

Maternal single nucleotide polymorphisms in the fatty acid desaturase 1 and 2 coding regions modify the impact of prenatal supplementation with DHA on birth weight

BACKGROUND Specific single nucleotide polymorphisms (SNPs) in the fatty acid desaturase (FADS) gene affect the activity and efficiency of enzymes that are responsible for the conversion of polyunsaturated fatty acids (PUFAs) into their long-chain active form. A high prevalence of SNPs that are associated with slow PUFA conversion has been described in Hispanic populations. OBJECTIVE We assessed the heterogeneity of the effect of prenatal supplementation with docosahexaenoic acid (DHA) on birth weight across selected FADS SNPs in a sample of Mexican women and their offspring. DESIGN We obtained information on the maternal genotype from stored blood samples of 654 women who received supplementation with 400 mg DHA/d or a placebo from weeks 18 to 22 of gestation through delivery as part of a randomized controlled trial conducted in Cuernavaca, Mexico. We selected 4 tag SNPs (rs174455, rs174556, rs174602, and rs498793) in the FADS region for analysis. We used an ANOVA to test for the heterogeneity of the effect on birth weight across each of the 4 SNPs. RESULTS The mean ± SD birth weight was 3210 ± 470 g, and the weight-for-age z score (WAZ) was -0.24 ± 1.00. There were no intention-to-treat differences in birth weights. We showed significant heterogeneity by SNP rs174602 (P= 0.02); offspring of carriers of alleles TT and TC in the intervention group were heavier than those in the placebo group (WAZ: -0.13 ± 0.14 and -0.20 ± 0.08 compared with -0.55 ± 0.15 and -0.39 ± 0.09, respectively); there were no significant differences in offspring of rs174602 CC homozygotes (WAZ: -0.26 ± 0.09 in the intervention group compared with -0.04 ± 0.09 in the placebo group). We showed no significant heterogeneity across the other 3 FADS SNPs. CONCLUSION Differential responses to prenatal DHA supplementation on the basis of the genetic makeup of target populations could explain the mixed evidence of the impact of DHA supplementation on birth weight. This trial was registered at clinicaltrials.gov as NCT00646360.