Paulina Pino

Prevention of iron-deficiency anemia: Comparison of high- and low-iron formulas in term healthy infants after six months of life

OBJECTIVES For bottle-fed babies or nursing infants who receive milk supplements, the American Academy of Pediatrics recommends the use of iron-fortified infant formula. Because these recommendations have not been universally adopted, the hematologic effects of currently available low-iron formulas need to be determined. STUDY DESIGN Healthy Chilean 6-month-old infants (without iron-deficiency anemia, born at term weighing > or 3.0 kg) who were totally or partially weaned from the breast were randomly allocated in a double-blind fashion to receive high-iron (n = 430) or low-iron formula (n = 405), containing an average of 12.7 mg/L or 2.3 mg/L, respectively, of elemental iron as ferrous sulfate. Iron status was determined at 12 months. RESULTS The prevalence of iron-deficiency anemia was not different in the high- and low-iron groups (2.8% versus 3.8%, p = 0.35). Nevertheless, infants receiving high-iron formula had somewhat higher levels of hemoglobin and serum ferritin, greater mean cell volumes, and lower erythrocyte protoporphyrin levels (p < 0.005). CONCLUSIONS Although high-iron formulas are more efficacious in improving iron status, currently available low-iron formulas may prevent iron-deficiency anemia in selected healthy, term infant populations with otherwise poor sources of dietary iron after 6 months of life. Formulas with relatively small amounts of iron appear to prevent iron-deficiency anemia. We speculate that the optimal level of iron fortification likely lies somewhere between the current levels in high- and low-iron formulas.

Fine particulate matter and wheezing illnesses in the first year of life.

Background: Recent evidence implicates fine particulate matter (PM2.5), principally from vehicular exhaust, as a major cause of increased mortality and morbidity. However, there are limited data on the impact of PM2.5 on infant respiratory illnesses. Methods: We conducted a cohort study of 504 infants recruited at 4 months of age from primary health care units in southeastern Santiago, Chile. Project physicians followed infants through the first year of life via monthly check-ups and by appointments on demand. We obtained data for fine particulate matter, sulfur dioxide (SO2), and nitrogen dioxide (NO2) from the governmental monitoring network. Results: The most frequent diagnosis during follow-up was wheezing bronchitis, occurring 19.5 times per 100 infants per month. After adjusting for sex, socioeconomic level, family history of asthma, minimum temperature, and number of older siblings, we found that an increase of 10 μg/m3 of PM2.5 24-hour average was related to a 5% increase (95% confidence interval 0–9%) in the risk for wheezing bronchitis (1-day lag). This association was present for different lags, with a maximum observed for a 9-day lag (9%; 6–12%). No consistent association was detected with NO2 or SO2 ambient levels. Lower socioeconomic status and having older siblings were also associated with the risk of wheezing bronchitis. The association of PM2.5 and wheezing bronchitis was stronger among infants with a family history of asthma than among infants without. Conclusions: Air pollution in the form of fine particulates, mostly from vehicular exhaust, may adversely affect infants’ respiratory health with potential for chronic effects later in life.

Factores de riesgo para el desarrollo psicomotor en lactantes nacidos en óptimas condiciones biológicas

OBJETIVO: Avaliar o efeito dos fatores de risco para o desenvolvimento infantil em criancas de nivel socioeconomico baixo, nascidos em otimas condicoes biologicas, mas expostos a condicoes sociais adversas. METODOLOGIA: Lactentes dos dois sexos, no total de 788, foram exaustivamente estudados quanto a alimentacao, crescimento, ambiente fisico e psicossocial controladas. Controlaram-se prospectivamente ate os 12 meses de idade, momento em que se avaliou o desenvolvimento mental (MDI) e o motor (PDI) atraves da escala de Bayley. A partir das variaveis medidas, identificaram-se 18 fatores de risco, que foram dicotomizados (baixo e alto risco). RESULTADOS: Amamentacao materna, temperamento da crianca, inteligencia materna e estimulo no lar associam-se consistentemente com MDI e PDI. Apos ajuste por co-variaveis, o estimulo no lar persiste como fator significativo na explicacao da variabilidade do MDI e do PDI, e o sexo da crianca aparece-se como fator condicionante do desenvolvimento motor. O efeito acumulado de sete ou mais fatores de risco associa-se a uma diminuicao significativa das pontuacoes de desenvolvimento. A combinacao de categorias de risco de temperamento infantil, inteligencia materna, papel do pai e estimulo no lar, atinge melhor predicao do desenvolvimento infantil que outras combinacoes analisadas. CONCLUSAO: Conclui-se que, mesmo para as criancas em otimas condicoes biologicas, o desenvolvimento psicomotor e afetado na presenca de condicoes ambientais adversas que agem simultaneamente.

Rapid drop in infant blood lead levels during the transition to unleaded gasoline use in Santiago, Chile

This study was conducted to relate blood lead levels in infants to changes in lead emissions in Santiago, Chile, a heavily polluted setting where leaded gasoline began to be replaced with unleaded gasoline in 1993. Over an 18-mo period, 422 infants had blood lead levels, cotinine, and iron status determined at 12 mo. Blood lead levels fell at an average rate of 0.5 μ/dl every 2 mo, from 8.3 to 5.9 μ/dl, as the city experienced a net fall of 30% in the quantity of leaded gasoline sold. Time progression, car ownership, serum cotinine, and type of housing were significantly associated with a blood lead level ⩾ 10 μ/dl. In this study, the authors demonstrated that infant blood lead levels, even if relatively low, can drop very rapidly in conjunction with decreases in environmental lead exposure.

Importancia del apoyo social en la permanencia de la abstinencia del consumo de drogas

We studied 306 subjects that were treated in drug addiction centers, financed by the NationalCouncil for Drug Control (CONACE). At discharge, social and demographic data were recordedand the Medical Outcomes Study (MOS) questionnaire was given to evaluate social support.Subjects that achieved abstinence at the moment of discharge were contacted six months laterand interrogated about eventual drug consumption thereafter.

Efectos agudos de las partículas respirables y del dióxido de azufre sobre la salud respiratoria en niños del área industrial de Puchuncaví, Chile

This study investigated the acute effect of air pollution on the respiratory health of children living in the industrial area of Puchuncaví, in Region V of Chile. The 114 children studied were from 6 to 12 years old; 57 of them had chronic respiratory symptoms and 57 did not. Each day for 66 days the air was checked for levels of sulfur dioxide (SO2) and of breathable particles that were < 10 microns (PM10). The children were selected and classified according to their susceptibility to chronic respiratory disease by means of a questionnaire used with 882 children living within the area of the emissions from a copper foundry and a thermoelectric plant. Each day, each studied childs peak expiratory flow (PEF) and incidence of respiratory symptoms were checked and recorded. Using regression models (generalized estimation equations), estimates were made of the association of SO2 and PM10 levels with PEF and the incidence of cough, expectoration, episodes of wheezing, dyspnea, and use of bronchodilators. Among the children who were initially symptomatic, an increase of 50 micrograms/m3 in the daily mean level of SO2 caused a reduction of -1.42 L/min (95% confidence interval (95% CI): -2.84 to -0.71) in the PEF of the following day. An increase of 30 micrograms/m3 in the cumulative concentration of PM10 over three days produced a PEF reduction of -2.84 L/min (95% CI: -4.26 to 0.00). With respect to symptoms, an increase of 30 micrograms/m3 in the weekly mean level of PM10 was related with a 26% increase (odds ratio (OR) = 1.26; 95% CI: 1.01 to 1.57) in the incidence of cough and of 23% (OR = 1.23; 95% CI: 1.00 to 1.50) in the incidence of expectoration. An increase of 50 micrograms/m3 in the mean level of SO2 for three days was associated with a 5% increase (OR = 1.05; 95% CI: 1.00 to 1.10) in the incidence of expectoration. An increase of 30 micrograms/m3 in the daily average of PM10 increased the use of bronchodilators two days later by 10% (OR = 1.10; 95% CI: 1.03 to 1.18). Among the initially asymptomatic children, a significant effect from PM10 exposure was found after an increase of 30 micrograms/m3 in the mean daily PM10 level, with a reduction of -1.34 L/min (95% CI: -2.68 to -0.67) in the PEF of the following day. A similar increase in the cumulative exposure over three days was associated with an increase of 9% in the incidence of episodes of wheezing (OR = 1.09; 95% CI: 1.01 to 1.31). It is concluded that high levels of PM10 and SO2 affect the respiratory health of children living in the industrial area of Puchuncaví.Se investigo el efecto agudo de la contaminacion atmosferica sobre la salud respiratoria en 114 ninos de 6 a 12 anos de edad residentes en la zona industrial de Puchuncavi, V Region de Chile: 57 con sintomas respiratorios cronicos y 57 asintomaticos. Durante 66 dias se midieron diariamente los niveles de particulas respirables de tamano < 10 mym (PM10) y de dioxido de azufre (SO2) en el aire. Los participantes fueron seleccionados y clasificados segun su susceptibilidad a la enfermedad respiratoria cronica, para lo cual se utilizo un cuestionario de sintomas respiratorios aplicado a un total de 882 ninos residentes en el area de influencia de las emisiones de una fundicion de cobre y de una central termoelectrica. Diariamente se registraron el flujo espiratorio maximo (FEM) y la incidencia de sintomas respiratorios. La asociacion de los niveles de PM10 y SO2 con el FEM y la incidencia de tos, expectoracion, sibilancias, disnea y uso de broncodilatadores fue estimada por modelos de regresion (ecuaciones estimativas generalizadas). En los ninos inicialmente sintomaticos, un incremento de 50 myg/m³ en el nivel medio diario de SO2 dio lugar a una reduccion de -1,42 L/min (intervalo de confianza de 95% (IC95%): -2,84 a -0,71) en el FEM del dia siguiente, mientras que un aumento de 30 myg/m³ en la concentracion acumulada de tres dias de PM10 produjo una disminucion de -2,84 L/min (IC95%: -4,26 a 0,00). Con respecto a los sintomas, un aumento de 30 myg/m³ en el nivel medio semanal de PM10 se relaciono con un incremento de 26% (razon de posibilidades (RP) = 1,26; IC95%: 1,01 a 1,57) en la incidencia de tos y de 23% (RP = 1,23; IC95%: 1,00 a 1,50) en la incidencia de expectoracion, un aumento de 50 myg/m³ en el nivel medio de SO2 durante tres dias se asocio a un incremento de 5% (RP = 1,05; IC95%: 1,00 a 1,10) en la incidencia de expectoracion y un aumento de 30 (myg/m³ en el promedio diario de PM10 incremento el uso de broncodilatadores dos dias mas tarde en 10% (RP = 1,10; IC95%: 1,03 a 1,18). En los ninos inicialmente asintomaticos solo se registraron efectos significativos por la exposicion a las PM10: tras un incremento de 30 myg/m³ en su nivel medio diario se observo una reduccion de -1,34 L/min (IC95%: -2,68 a -0,67) en el FEM del dia siguiente y un incremento similar en la exposicion acumulada de tres dias se asocio a un aumento de 9% en la incidencia de sibilancias (RP = 1,09; IC95%: 1,01 a 1,31). Se concluye que la salud respiratoria de los ninos residentes en el area industrial de Puchuncavi se ve afectada por los altos niveles de PM10 y SO2.

Higher Infant Blood Lead Levels with Longer Duration of Breastfeeding

OBJECTIVE To determine whether longer breastfeeding is associated with higher infant lead concentrations. STUDY DESIGN Data were analyzed from 3 studies of developmental effects of iron deficiency in infancy: Costa Rica (1981-1984), Chile (1991-1996), and Detroit (2002-2003). The relation between duration of breastfeeding and lead levels was assessed with Pearson product-moment or partial correlation coefficients. RESULTS More than 93% of the Costa Rica and Chile samples was breastfed (179 and 323 breastfed infants, respectively; mean weaning age, 8-10 months), as was 35.6% of the Detroit sample (53 breastfed infants; mean weaning age, 4.5 months). Lead concentrations averaged 10.8 microg/dL (Costa Rica, 12-23 months), 7.8 microg/dL (Chile, 12 months), and 2.5 microg/dL (Detroit, 9-10 months). Duration of breastfeeding as sole milk source and total breastfeeding correlated with lead concentration in all samples (r values = 0.14-0.57; P values = .06-<.0001). CONCLUSIONS Longer breastfeeding was associated with higher infant lead concentration in 3 countries, in 3 different decades, in settings differing in breastfeeding patterns, environmental lead sources, and infant lead levels. The results suggest that monitoring lead concentrations in breastfed infants be considered.

DOES PREVENTING IRON-DEFICIENCY ANEMIA (IDA) IMPROVE DEVELOPMENTAL TEST SCORES? • 800

Several studies have shown that IDA in infants is associated with lower developmental test scores, but this association is confounded by environmental disadvantages. A double-blind placebo-controlled preventive trial was undertaken in which 944 healthy Chilean 6-mo-old infants were randomly assigned to supplemental iron or no added iron (current feeding routine in Chile) until 12 months of age. All infants were born at term, BW > 3.0 kg, had no acute or chronic illness, had normal Hb levels at 6 mos, and almost all had been breast fed. Supplemented and unsupplemented groups were comparable in growth, family background, and Hb levels at study entry. At 12 mo, the supplemented group had less anemia (Hb 90% power to detect a 3 point difference if present. The study suggests that factors other than IDA per se account for lower Bayley scores observed in iron-deficient anemic infants. Differences between this and other samples suggest such factors might be environmental disadvantage, no breast feeding, BW 6 mo. Funded by NICHD; milk and formula donated by Ross Laboratories. Table

Exposure to lead from a storage site associated with intellectual impairment in Chilean children living nearby.

Abstract This study assesses the degree of impairment of childrens IQ scores due to exposure to lead from a storage site. In 2005, we studied 192 children in Antofagasta, Chile, age 7–16 years who had been exposed to a lead storage site from birth until its removal in 1998. We used past (1998) and current (2005) blood lead levels as explanatory variables for IQ, which was measured once in 2005 using the WISC-r test. Multilevel mixed-effects linear regression models were constructed, adjusting for potential confounders. Current blood lead level (BPb, 2005) was associated with a significant decrease in full-scale IQ (P value = 0.03), whereas blood lead level measured in 1998 (BPb, 1998) showed an inverse but not significant association with full-scale IQ (P value = 0.35). The findings provide evidence that exposure to an open source of environmental lead can exert an effect on IQ. Policy efforts should be targeted to prevent lead exposure to avoid childrens intellectual impairment.

Alcohol-Attributable Mortality and Years of Potential Life Lost in Chile in 2009

AIMS The aim of the study was to estimate mortality and years of potential life lost (YPLL) attributable to alcohol consumption in 2009 in Chile. METHODS The population considered for this study included those 15 years and over. Exposure to alcohol in the population was estimated by triangulating the records of alcohol per capita consumption in Chile with information from the Eighth National Study of Drugs in the General Population (2008). The effect of alcohol consumption on each cause of death (relative risk) was extracted from previously published meta-analyses. With this information we estimated the alcohol-attributable fraction (AAF) and deaths and YPLL due to alcohol consumption. The confidence intervals for the AAF were estimated with Monte Carlo sampling using the estimated variances of the exposure prevalence and relative effect. RESULTS The estimated total number of deaths attributable to alcohol consumption was 8753 (95% CI: 6257, 11,584) corresponding to 9.8% (95% CI: 7.01%, 12.98%) of all deaths in Chile in 2009. The total estimated YPLL attributable to alcohol were 195,475 (95% CI: 164,287, 227,726), corresponding to 21.5% (95% CI: 18.1%, 25.0%) of total YPLL for that year in Chile. CONCLUSION Alcohol consumption is a major risk factor and accounts for nearly one of ten deaths in Chile. These results may be used to guide the design of public health policies and evaluations.