Descriptive Epidemiology of Objectively Measured Walking Among US Pregnant Women: National Health and Nutrition Examination Survey, 2005-2006

Independent and joint effects of neighborhood-level environmental and socioeconomic exposures on body mass index in early childhood: The environmental influences on child health outcomes (ECHO) cohort

Past studies support the hypothesis that the prenatal period influences childhood growth. However, few studies explore the joint effects of exposures that occur simultaneously during pregnancy. To explore the feasibility of using mixtures methods with neighborhood-level environmental exposures, we assessed the effects of multiple prenatal exposures on body mass index (BMI) from birth to age 24 months. We used data from two cohorts: Healthy Start (n = 977) and Maternal and Developmental Risks from Environmental and Social Stressors (MADRES; n = 303). BMI was measured at delivery and 6, 12, and 24 months and standardized as z-scores. We included variables for air pollutants, built and natural environments, food access, and neighborhood socioeconomic status (SES). We used two complementary statistical approaches: single-exposure linear regression and quantile-based g-computation. Models were fit separately for each cohort and time point and were adjusted for relevant covariates. Single-exposure models identified negative associations between NO2 and distance to parks and positive associations between low neighborhood SES and BMI z-scores for Healthy Start participants; for MADRES participants, we observed negative associations between O3 and distance to parks and BMI z-scores. G-computations models produced comparable results for each cohort: higher exposures were generally associated with lower BMI, although results were not significant. Results from the g-computation models, which do not require a priori knowledge of the direction of associations, indicated that the direction of associations between mixture components and BMI varied by cohort and time point. Our study highlights challenges in assessing mixtures effects at the neighborhood level and in harmonizing exposure data across cohorts. For example, geospatial data of neighborhood-level exposures may not fully capture the qualities that might influence health behavior. Studies aiming to harmonize geospatial data from different geographical regions should consider contextual factors when operationalizing exposure variables.

Associations Between Maternal Physical Activity, Maternal Lipid Levels, and Infant Anthropometric Outcomes at Two Weeks of Age

BACKGROUND

This study determined the relationship between physical activity (PA), circulating lipids throughout pregnancy and infant anthropometric outcomes at birth and 2 weeks of age.

METHODS

Women (N = 234) with normal weight (NW, BMI 18.5-24.9 kg/m²) and with overweight and class I obesity (OW/OB, BMI 25-35 kg/m²) were categorized into high and low PA based on average cohort steps during pregnancy (8099 steps/day). Circulating fasting lipids were measured at each trimester. Standardized methods were used to obtain anthropometrics measures. Infant body composition was estimated by quantitative nuclear magnetic resonance (EchoMRI-AH small; ECHO Medical Systems).

RESULTS

Women with NW who had higher activity had lower circulating triglycerides (TG) and total cholesterol (TC) levels at 12 weeks compared to women with NW and low activity (p < 0.05). Women with OW/OB and high activity level throughout pregnancy had lower circulating TG, and low density lipoprotein (LDL), at 12 weeks, lower LDL at 24 weeks, and lower TG at 36 weeks compared to the women with OW/OB who had low activity levels (p < 0.05). For children born to women with OW/OB, maternal circulating TG and LDL were most associated with infant anthropometrics at 2 weeks of age.

CONCLUSION

This study supports that higher PA during pregnancy is associated with lower lipid levels throughout pregnancy with a greater effect size in women with OW/OB. Maternal lipids were associated with anthropometrics and infant body composition at two weeks of life in women with OW/OB.

Walking in pregnancy and prevention of insomnia in third trimester using pedometers: study protocol of Walking_Preg project (WPP). A randomized controlled trial

BACKGROUND

Previous studies in pregnancy have not focused in evaluating the effect of walking during pregnancy and prevention of insomnia. Our general objective is to determine the effect of a walking program in preventing the appearance of insomnia in the third trimester of pregnancy, increasing sleep quality and improving quality of life throughout pregnancy.

METHODS

Randomized Controlled trial in parallel in healthy sedentary pregnant women (n = 265), Walking_Preg Project (WPP), from university hospital in Granada, Spain. At 12th gestational week (GW), they will be invited to participate and randomly assigned to one of the three arms of study: the intervention group I1 (pedometer, goal of 11,000 steps/day), intervention group I2 (pedometer, no goal) and control (no pedometer). Duration of intervention: 13-32 GW. At 12th, 19th and 31st GW the average steps/day will be measured in groups I1 and I2. At 13th, 20th and 32nd GW, Athens Insomnia Scale (AIS), Pittsburgh Sleep Quality Index (PSQI), Adherence to Mediterranean Diet (AMD), physical activity (short IPAQ), quality of life (PSI), and consumption of toxic substances (caffeine, illegal drugs, alcohol and tobacco) will be collected. Student t test or Mann-Whitney U will be used to compare 19th and 31st GW mean of daily steps between I1 and I2 groups. To compare differences between groups in terms of frequency of insomnia/quality of life for each trimester of pregnancy, Pearson's Chi-square test or Fisher's exact test will be used. To determine differences in hours of sleep and quality of sleep throughout each trimester of pregnancy, analysis of variance or Friedman test will be used. McNemar-Bowker test will be used to assess differences in life quality in pre-post analyses in the 3 arms. We will use Stata 15 statistical software.

DISCUSSION

promoting walking in second half of pregnancy through use of pedometer and health pre-registration of a goal to be achieved -'10,000-11,000 steps a day'- should prevent appearance of insomnia in third trimester, will increase sleep quality and quality of life in pregnant women.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03735381 . Registered 8th November, 2018.

Adaptation of an exercise intervention for pregnant women to community-based delivery: a study protocol

INTRODUCTION

Despite well-established guidelines and benefits to exercise, the majority of pregnant women in the USA fail to meet recommended activity levels. Studies need to determine feasible ways to translate clinical interventions to community settings by engaging pregnant women in widely accessible locations to ensure benefits to more women. The aim of this study is to adapt and determine feasibility, acceptability and fidelity of the research clinic-based Expecting intervention (NCT02125149) with pregnant women with obesity in community settings.

METHODS AND ANALYSIS

We will use the Replicating Effective Programs (REP) to guide the adaptation and implementation of the research clinic-based intervention into the community. REP provides a four-phase process for implementing evidence-based interventions including collection of feedback from community stakeholders, iterative piloting of the intervention in the community and a process for standardising the intervention across community settings. Following adaptation, the updated intervention will be piloted. The pilot study will include 60 expecting women. We will randomise half to receive the community-adapted Expecting intervention (intervention, N=30) and half to receive standard of care (control, N=30). Feasibility and Acceptability of Intervention Measures are primary outcomes as key indicators of feasibility. Secondary outcomes will include the number of intervention sessions completed, the change in the number of minutes of physical activity as measured by accelerometer, as well as change in health indicators from enrolment to time of delivery and 6 months post-delivery (ie, body mass index, blood pressure and total cholesterol).

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board (#260132). Findings will be shared with study participants and stakeholder advisors through written summaries and in-person presentations; results will also be shared through presentations at scientific conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04298125; Pre-results.

Maternal residential greenness and congenital heart defects in infants: A large case-control study in Southern China

BACKGROUND

Proximity to greenness has shown protective effects on coronary heart diseases by limiting exposure to environmental hazards, encouraging physical activity, and reducing mental stress. However, no studies have previously evaluated the impacts of greenness on congenital heart defects (CHDs). We examined the association between maternal residential greenness and the risks of CHDs.

METHODS

We conducted a case-control study (8042 children with major CHDs and 6887 controls without malformations) in 21 cities in Southern China, 2004 - 2016. CHDs cases were diagnosed and verified by obstetrician, pediatrician, or pediatric cardiologists, within one year. We estimated maternal residential greenness using satellite-derived normalized difference vegetation index (NDVI) in zones of 500 meters (m) and 1000 m surrounding participants' residences. Logistic regression models were used to assess NDVI-CHD relationships adjusting for confounders.

RESULTS

Interquartile range NDVI increases within 500 m or 1000 m were associated with odds ratios (OR) of 0.95 (95% confidence interval (CI): 0.92, 0.98) and 0.94 (95%CI: 0.91, 0.97) for total CHDs respectively. Air pollutants mediated 52.1% of the association. We also identified a protective threshold at 0.21 NDVI on CHD. Similar protective effects from greenness were found in most CHDs subtypes. The protective associations were stronger for fall, urban or permanent residents, higher household income maternal age ≤35 years of age, and high maternal education (ORs: ranged from 0.85 to 0.96).

CONCLUSION

Our findings suggest a beneficial effect of maternal residential greenness on CHDs. Further studies are needed to confirm our findings, which will help to refine preventive health and urban design strategies.

Sedentary behavior patterns in non-pregnant and pregnant women

Sedentary behavior has been associated with adverse health outcomes among pregnant women; however, few studies have characterized sedentary behavior patterns in this population. We described patterns of accelerometer-determined indicators of sedentary behavior among a national sample of US pregnant (n = 234) women and non-pregnant (n = 1146) women participating in the NHANES 2003-06 cycles. We included women with ≥ 4 days of accelerometer wear of ≥ 10 h/day. A count threshold of < 100 cpm was used to describe sedentary behavior as: 1) total accumulated sedentary time by bout length categories; 2) accumulated sedentary time within discrete bout length categories; 3) mean, median, and usual bout length; and 4) and bout frequency. Both non-pregnant and pregnant women spent up to 60% of their accelerometer wear time in sedentary behavior depending on the minimum bout threshold applied. Sedentary time was higher among pregnant women compared to non-pregnant women when lower bout thresholds (i.e. 10 min or less) were applied. The majority of total sedentary time was accumulated in bouts lasting < 10 min. The women averaged less than two prolonged sedentary bouts (i.e., ≥ 30 min) per day, which accounted for nearly 20% of total accumulated sedentary time. When applying a minimum threshold of at least 15 min, sedentary time increased across pregnancy trimesters, while sedentary time was similar across trimesters when using lower thresholds. These findings provide the first characterization of accelerometer-determined indicators of sedentary behavior in pregnant women. The minimum bout threshold applied influenced estimates of sedentary time and patterns sedentary time accumulation across pregnancy trimesters.

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How we operationalized sedentary behavior affects estimates of sedentary time.

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How women accumulate their sedentary time, changes over trimesters of pregnancy.

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Most sedentary bouts are short in duration (i.e. < 10 min).

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Long sedentary bouts (i.e. ≥ 30 min) account for ~ 20% of total sedentary time.