Predictors of Developmental Patterns of Obesity in Young Children

Educational Review: The Impact of Perinatal Oxidative Stress on the Developing Kidney

Oxidative stress occurs when there is an imbalance between reactive oxygen species/reactive nitrogen species and antioxidant systems. The interplay between these complex processes is crucial for normal pregnancy and fetal development; however, when oxidative stress predominates, pregnancy related complications and adverse fetal programming such as preterm birth ensues. Understanding how oxidative stress negatively impacts outcomes for the maternal-fetal dyad has allowed for the exploration of antioxidant therapies to prevent and/or mitigate disease progression. In the developing kidney, the negative impact of oxidative stress has also been noted as it relates to the development of hypertension and kidney injury mostly in animal models. Clinical research addressing the implications of oxidative stress in the developing kidney is less developed than that of the neurodevelopmental and respiratory conditions of preterm infants and other vulnerable neonatal groups. Efforts to study the oxidative stress pathway along the continuum of the perinatal period using a team science approach can help to understand the multi-organ dysfunction that the maternal-fetal dyad sustains and guide the investigation of antioxidant therapies to ameliorate the global toxicity. This educational review will provide a comprehensive and multidisciplinary perspective on the impact of oxidative stress during the perinatal period in the development of maternal and fetal/neonatal complications, and implications on developmental programming of accelerated aging and cardiovascular and renal disease for a lifetime.

Infant temperament is associated with maternal feeding behaviors in early infancy

Parental feeding practices shape infant eating behaviors and may impact obesity risk. For example, feeding on a schedule and using food to soothe have been associated with greater infant weight gain and future obesity risk. Most studies focus on parental determinants of feeding practices, but infant temperament might influence feeding practices parents select. Studies examining associations of infant temperament with parental feeding practices in early infancy are needed. Thus, the purpose of this cross-sectional, observational study was to test the hypothesis that infant temperament would be associated with use of food to soothe and feeding on a schedule. Mother-infant dyads (N = 98) from 3 parent birth cohort studies presented for clinic visits at infant age of 3-5 months. Mothers completed a demographic questionnaire. Feeding practices (use of food to soothe and feeding on a schedule) and maternal perceptions of 3 dimensions of infant temperament (surgency, orienting/regulating, and negative affect) were collected by survey. Spearman partial correlations were used to examine if any of the 3 infant temperament dimensions were associated with use of food to soothe or feeding on a schedule, adjusting for maternal marital status, race/ethnicity, BMI, infant age at the visit, and infant weight-for-length z-score. Greater perceived infant surgency/extraversion was associated with greater use of food to calm (Spearman partial r = 0.25, p < 0.05), but not feeding on a schedule (Spearman partial r = -0.11, p = 0.31). Greater perceived infant negative affect was associated with greater use of food to calm (Spearman partial r = 0.21, p < 0.05). Perceived infant orienting/regulating was not associated with either of the feeding practices examined. These results provide evidence that as early as 3-5 months of age, perceived infant temperament is associated with maternal feeding practices which influence infant growth outcomes.

Prenatal exposure to ambient air pollutants and early infant growth and adiposity in the Southern California Mother's Milk Study

BACKGROUND

Prior epidemiological and animal work has linked in utero exposure to ambient air pollutants (AAP) with accelerated postnatal weight gain, which is predictive of increased cardiometabolic risk factors in childhood and adolescence. However, few studies have assessed changes in infant body composition or multiple pollutant exposures. Therefore, the objective of this study was to examine relationships between prenatal residential AAP exposure with infant growth and adiposity.

METHODS

Residential exposure to AAP (particulate matter < 2.5 and 10 microns in aerodynamic diameter [PM2.5, PM10]; nitrogen dioxide [NO2]; ozone [O3]; oxidative capacity [Oxwt: redox-weighted oxidative potential of O3 and NO2]) was modeled by spatial interpolation of monitoring stations via an inverse distance-squared weighting (IDW2) algorithm for 123 participants from the longitudinal Mother's Milk Study, an ongoing cohort of Hispanic mother-infant dyads from Southern California. Outcomes included changes in infant growth (weight, length), total subcutaneous fat (TSF; calculated via infant skinfold thickness measures) and fat distribution (umbilical circumference, central to total subcutaneous fat [CTSF]) and were calculated by subtracting 1-month measures from 6-month measures. Multivariable linear regression was performed to examine relationships between prenatal AAP exposure and infant outcomes. Models adjusted for maternal age, pre-pregnancy body mass index, socioeconomic status, infant age, sex, and breastfeeding frequency. Sex interactions were tested, and effects are reported for each standard deviation increase in exposure.

RESULTS

NO2 was associated with greater infant weight gain (β = 0.14, p = 0.02) and TSF (β = 1.69, p = 0.02). PM10 and PM2.5 were associated with change in umbilical circumference (β = 0.73, p = 0.003) and TSF (β = 1.53, p = 0.04), respectively. Associations of Oxwt (pinteractions < 0.10) with infant length change, umbilical circumference, and CTSF were modified by infant sex. Oxwt was associated with attenuated infant length change among males (β = -0.60, p = 0.01), but not females (β = 0.16, p = 0.49); umbilical circumference among females (β = 0.92, p = 0.009), but not males (β = -0.00, p = 0.99); and CTSF among males (β = 0.01, p = 0.03), but not females (β = 0.00, p = 0.51).

CONCLUSION

Prenatal AAP exposure was associated with increased weight gain and anthropometric measures from 1-to-6 months of life among Hispanic infants. Sex-specific associations suggest differential consequences of in utero oxidative stress. These results indicate that prenatal AAP exposure may alter infant growth, which has potential to increase childhood obesity risk.

Developmental and Early Life Origins of Cardiometabolic Risk Factors: Novel Findings and Implications

The intent of this review is to critically consider the data that support the concept of programming and its implications. Birth weight and growth trajectories during childhood are associated with cardiometabolic disease in adult life. Both extremes, low and high birth weight coupled with postnatal growth increase the early presence of cardiometabolic risk factors and vascular imprinting, crucial elements of this framework. Data coming from epigenetics, proteomics, metabolomics, and microbiota added relevant information and contribute to better understanding of mechanisms as well as development of biomarkers helping to move forward to take actions. Research has reached a stage in which sufficiently robust data calls for new initiatives focused on early life. Prevention starting early in life is likely to have a very large impact on reducing disease incidence and its associated effects at the personal, economic, and social levels.

Grow well/Crecer bien: a protocol for research on infant feeding practices in low-income families

BACKGROUND

The prevalence of obesity among children remains high. Given obesity's significant lifelong consequences, there is great interest in preventing obesity early in life. There is a need to better understand the relation of common infant feeding styles and practices to obesity in infants using longitudinal study designs. There is also an urgent need to understand the role of caregivers other than mothers in feeding. A better understanding of variation in feeding styles and practices can inform the identification of risk groups and the tailoring of interventions to them.

METHODS

In partnership with Early Head Start programs across four counties in southern California, mothers and infants will be enrolled in a two-year longitudinal study collecting survey and anthropometric data. A subsample of mothers and their selected other caregivers will participate in qualitative research involving feeding diaries and dyadic interviews. The results will be used to develop and test an enhanced nutrition education program.

DISCUSSION

We outline a study methodology to examine feeding styles and practices and their association with early childhood obesity risk and enhance an existing intervention to promote healthy infant feeding and growth among children in low-income families.