The Joint Association of Small for Gestational Age and Nighttime Sleep with Blood Pressure in Childhood

Integration of proteomics with prospective birth cohort to elucidate early life origins of cardiometabolic diseases: rationale, study design, lab assay, and quality control

There is growing evidence that the plasma proteome provides insights into personal health status at different stages of life. However, limited data are available on high-throughput proteomic studies in pediatric populations, especially, using prospective birth cohorts. We launched a proteomics study in 990 children from a US predominantly urban, low-income, multi-ethnic prospective Boston Birth Cohort (BBC, referred as "BBC proteomics study"), which aimed to leverage proteomics to investigate the biological pathways underlying the link between preterm birth and child long-term cardiometabolic health. The objective of this paper is to describe the rationale, study design, proteomic assay and quality control steps for the BBC proteomics study in a subset of children with available proteomic profiling. Using the OLINK® Explore 3072 platform, proteomic profiling was performed in cord plasma at birth and in postnatal plasma collected during early childhood. Quality control (QC) steps were performed, including calculation of coefficient of variation (CV), missingness rates per sample or per protein, principal component analyses to identify clustering and outliers, and correlation analyses among the duplicates to indicate reproducibility. A total of 2,941 proteins from eight OLINK panels were successfully measured at both time points. Almost 100% of samples passed lab-prespecified QC. Approximately 89% of proteins were detected in > 50% samples; 79.6% had intra-CV < 15% and 79.9% of had inter-CV < 30%. Four samples were identified as outliers due to high missingness rates. Our data also demonstrated that this assay had a good reproducibility with correlation coefficient (r) > 0.65 in most of the duplicates, although we also identified potential batch effects. In conclusion, our data suggests that this high-throughput proteomic profiling is feasible and reproducible in archived plasma samples, including cord blood. We anticipated that successful completion of this proteomics study will help identify novel predictive biomarkers and therapeutic targets so that high-risk newborns can be identified, and effective interventions can be initiated during the earliest developmental window when they may have the greatest life-long benefit.

Mediterranean-Style Diet and Birth Outcomes in an Urban, Multiethnic, and Low-Income US Population

Findings on the role of Mediterranean-style diet (MSD) on duration of pregnancy and birth weight have been inconsistent and based largely on Non-Hispanic white populations, making it unclear as to whether they could extend to African Americans who are at a higher risk of unfavorable birth outcomes. Our study addresses this gap using a large urban, multiethnic, predominantly low-income cohort of mother-infant dyads from Boston, MA, USA. Dietary information was obtained via food frequency questionnaires; health information including birth outcomes were extracted from medical records. A Mediterranean-style diet score (MSDS) was formulated based on intake history, and linear and log-binomial regressions were performed to assess its association with birth outcomes. After adjustment, the lowest MSDS quintile from the overall sample was found to be associated with an increased relative risk (RR) of overall preterm birth (RR 1.18; 95% CI: 1.06-1.31), spontaneous preterm birth (1.28; 1.11-1.49), late preterm birth (1.21; 1.05-1.39), and low birth weight (1.11; 1.01-1.22), compared to the highest quintile. The findings were similar for the African American sample. Our study adds to the current understanding of the diet's influence on birth outcomes by demonstrating that adherence to MSD may improve birth outcomes for African American women.

Pre-pregnancy underweight and obesity are positively associated with small-for-gestational-age infants in a Chinese population

The association between suboptimal pre-pregnancy body mass index (BMI) and small-for-gestational-age (SGA) infants is not well defined. We investigated the association between pre-pregnancy BMI and the risk of SGA infants in a Chinese population. We performed a cohort study among 12029 mothers with a pregnancy. This cohort consisted of pregnant women that were: normal-weight (62.02%), underweight (17.09%), overweight (17.77%) and obese (3.12%). Birth sizes were reduced in the underweight and obese groups compared with the normal-weight group. Linear regression analysis indicated that birth size was positively associated with BMI in both the underweight and normal-weight groups. Further analysis showed that 12.74% of neonates were SGA infants in the underweight group, higher than 7.43% of neonates reported in the normal-weight group (adjusted RR = 1.92; 95% CI: 1.61, 2.30). Unexpectedly, 17.60% of neonates were SGA infants in the obese group, much higher than the normal-weight group (adjusted RR = 2.17; 95% CI: 1.57, 3.00). Additionally, 18.40% of neonates were large-for-gestational-age (LGA) infants in the obese group, higher than 7.26% of neonates reported in the normal-weight group (adjusted RR = 3.00; 95% CI: 2.21, 4.06). These results suggest that pre-pregnancy underweight increases the risk of SGA infants, whereas obesity increases the risks of not only LGA infants, but also SGA infants.