Prenatal exposure to air pollutant mixtures and birthweight in the upstate KIDS cohort.

BACKGROUND: Single-pollutant models have linked prenatal PM2.5 exposure to lower birthweight. However, analyzing air pollutant mixtures better captures pollutant interactions and total effects. Unfortunately, strong correlations between pollutants restrict traditional methods. OBJECTIVES: We explored the association between exposure to a mixture of air pollutants during different gestational age windows of pregnancy and birthweight. METHODS: We included 4,635 mother-infant dyads from a New York State birth cohort born 2008-2010. Air pollution data were sourced from the EPA's Community Multiscale Air Quality model and matched to the census tract centroid of each maternal home address. Birthweight and gestational age were extracted from vital records. We applied linear regression to study the association between prenatal exposure to PM2.5, PM10, NOX, SO2, and CO and birthweight during six sensitive windows. We then utilized Bayesian kernel machine regression to examine the non-linear effects and interactions within this five-pollutant mixture. Final models adjusted for maternal socio-demographics, infant characteristics, and seasonality. RESULTS: Single-pollutant linear regression models indicated that most pollutants were associated with a decrement in birthweight, specifically during the two-week window before birth. An interquartile range increase in PM2.5 exposure (IQR: 3.3 µg/m3) from the median during this window correlated with a 34 g decrement in birthweight (95 % CI: -54, -14), followed by SO2 (IQR: 2.0 ppb; ß: -31), PM10 (IQR: 4.6 µg/m3; ß: -29), CO (IQR: 60.8 ppb; ß: -27), and NOX (IQR: 7.9 ppb; ß: -26). Multi-pollutant BKMR models revealed that PM2.5, NOX, and CO exposure were negatively and non-linearly linked with birthweight. As the five-pollutant mixture increased, birthweight decreased until the median level of exposure. DISCUSSION: Prenatal exposure to air pollutants, notably PM2.5, during the final two weeks of pregnancy may negatively impact birthweight. The non-linear relationships between air pollution and birthweight highlight the importance of studying pollutant mixtures and their interactions.

Early Infant Feeding Practices and Associations with Growth in Childhood.

Early infant growth trajectories have been linked to obesity risk. The aim of this study was to examine early infant feeding practices in association with anthropometric measures and risk of overweight/obesity in childhood. A total of 2492 children from Upstate KIDS, a population-based longitudinal cohort, were included for the analysis. Parents reported breastfeeding and complementary food introduction from 4 to 12 months on questionnaires. Weight and height were reported at 2-3 years of age and during later follow-up at 7-9 years of age. Age and sex z-scores were calculated. Linear mixed models were conducted, adjusting for maternal and child sociodemographic factors. Approximately 54% of infants were formula-fed at <5 months of age. Compared to those formula-fed, BMI- (adjusted B, -0.23; 95% CI: -0.42, -0.05) and weight-for-age z-scores (adjusted B, -0.16; -0.28, -0.03) were lower for those exclusively breastfed. Infants breastfed for ≥12 months had a lower risk of being overweight (aRR, 0.33; 0.18, 0.59) at 2-3 years, relative to formula-fed infants. Compared to introduction at <5 months, the introduction of fruits and vegetables between 5 and 8 months was associated with lower risk of obesity at 7-9 years (aRR, 0.45; 0.22, 0.93). The type and duration of breastfeeding and delayed introduction of certain complementary foods was associated with lower childhood BMI.

Macronutrient Adequacy of a Mediterranean-type Meal Examined at Recommended and Below Recommended Energy Values.

Background: Mediterranean style eating pattern is regarded as among the worlds' healthiest. Numerous studies have shown that the Mediterranean eating pattern can promote weight loss, however, if combined with caloric restriction as promoted via internet sites, are inherent advantages retained or do macronutrients fall below recommended levels and if so, at which energy values does this occur? Objective: To address this question. Methods: We have formulated a meal which was developed from items on menus in Barcelona, Spain. Macronutrients were determined using NDSR software and the meal was assessed for carbohydrate, fat and protein content at recommended levels of 2500 and 2000 kcal/day as well as at 1600, 1200 and 800 kcal/day through control of portion sizes. Authenticity of the meal as being Mediterranean- type was verified by comparison to established standards contained in dietary guidelines for Americans as well as similarity to percent of macronutrients published in the literature. Results: Comparison of our results to guidelines for a Mediterranean style eating pattern showed fruit, protein and oil intake to be sufficient but not so for the vegetables, grains and dairy food groups. All macronutrients reached dietary recommended amounts when analyzed at energy values of 2500 and 2000 kcal/day. Fat and carbohydrate content satisfied recommended amounts at intakes of 1600 and 1200 kcal/day but the amount of protein was insufficient at all values below 2000 kcal/day. Conclusion: Although a Mediterranean-style eating pattern is among the healthiest, in order to maintain macronutrient adequacy, it should not be energy compromised.