Maternal Body Mass Index, Neighborhood Characteristics and Early Childhood Obesity

Objective: Childhood obesity is a leading cause of morbidity among US children with nearly 1 in 10 children ages 2 – 5 with a BMI greater than the 95th percentile. Childhood obesity is associated with multiple comorbidities including early-onset type II diabetes, sleep apnea, mood disorders, social marginalization and bullying. Moreover, obese children are more likely to become obese adults. Maternal pre-pregnancy BMI is one gestational exposure consistently associated with offspring obesity. Neighborhood characteristics, including socioeconomic deprivation and food environment, represent shared maternal-child exposures which have also been associated with child obesity. The objective of this thesis was to evaluate the association between maternal socio-demographic, pre-pregnancy health, pregnancy health and neighborhood characteristics and child BMI percentile at 5 years (aim 1) and BMI trajectory from 2 – 8 years (aim 2). Methods: The study sample was drawn from the Delaware Mother and Baby Cohort (DMBC), a prospective cohort of 4,852 women who delivered at Christiana Care Health System (CCHS) in Newark, Delaware between January 1, 2004 and December 31, 2007; and who accessed pediatric care for their child through the Nemours Children’s Health System (NCHS) at least once between January 1, 2004 and May 31, 2011. The DMBC was linked with Delaware birth certificates, the 2010 US Census and the Delaware Healthy Toolkit Food Resource Database. The primary dependent variables were age- and sex- standardized BMI percentile at age 5 (aim 1) and rate of change in BMI (kg/m2/month) from 2 - 8 years (aim 2). The main independent variables included maternal pre-pregnancy BMI, neighborhood socioeconomic deprivation and distance between mother’s residence and closest healthy food outlet. Associations found in bivariable analyses informed multivariable modeling. Multivariable multinomial logistic regression was performed to identify the independent influence of maternal pre-pregnancy BMI, neighborhood food environment and census-tract socioeconomic deprivation on child BMI percentile at 5-years and BMI trajectory from 2 to 8 years after adjusting for other covariables. For all analyses, p-values < 0.05 were considered statistically significant. All analyses were performed using Stata/IC Version 13.0 and Comprehensive R Archive Network (R) Version 3.4.2. This study was approved by the Christiana Care Health System and University of Wisconsin – Madison Institutional Review Boards. Results: A total of 3,101 (63.9%) of DMBC participants met inclusion criteria for aim 1 and 3,862 (79.6%) of DMBC participants met inclusion criteria for aim 2. The sample characteristics were similar for both study aims; one-quarter of DMBC women had a pre-pregnancy BMI ≥ 30 kg/m2, one-quarter of dyads lived < 0.5 miles from the nearest healthy food outlet and 35% of participants resided in census-tracts with extreme socioeconomic deprivation. In multivariable models, maternal pre-pregnancy BMI was strongly associated with overweight and obesity at 5-years as well as steady and rapid gain BMI trajectory from 2 – 8 years old; it was not associated with a declining BMI trajectory. Children who resided in communities characterized by extreme socio-economic deprivation had significantly higher odds of obesity at 5-years than their counterparts in less deprived communities but proximity to healthy food outlets was not associated with child BMI at 5-years. Neither census-tract socio-economic deprivation nor neighborhood food environment was associated with child BMI trajectory. Conclusions: The odds of childhood obesity at 5-years and steady or rapid childhood BMI gain from 2 – 8 years were independently associated with maternal pre-pregnancy obesity after adjusting for maternal socio-demographic, pre-pregnancy health, pregnancy health and community characteristics. BMI at age 5 but not BMI trajectory was independently associated with neighborhood census-tract socioeconomic deprivation. Local food environment was not associated with child BMI or BMI trajectory. Children of obese women carry the highest odds of obesity in early childhood. Additional research is needed to better understand the association between neighborhood characteristics and early childhood BMI among offspring of obese and non-obese mothers

Residency Exposures and Anticipated Future Involvement in Community Settings

Objective— To assess how exposures to community activities in residency impact anticipated future involvement in community child health settings. Methods— Prospective cohort study of pediatric residents from 10 programs (12 sites) who completed training between 2003 and 2009. Residents reported annual participation for ≥8 days in each of 7 community activities (eg, community settings, child health advocacy) in the prior year. At the start and end of residency, residents reported anticipated involvement in 10 years in 8 community settings (eg, school, shelter). Anticipated involvement was dichotomized: moderate/ substantial (“high”) versus none/limited (“low”). Logistic regression modeled whether residency exposures independently influenced anticipated future involvement at the end of residency. Results— A total of 683 residents completed surveys at the start and end of residency (66.8% participation). More than half of trainees reported ≥8 days’ of involvement in community settings (65.6%) or child health advocacy (53.6%) in residency. Fewer anticipated high involvement in at least 1 community setting at the end of residency than at the start (65.5% vs 85.6%, P < .001). Participation in each community activity mediated but did not moderate relations between anticipated involvement at the start and end of residency. In multivariate models, exposure to community settings in residency was associated with anticipated involvement at end of residency (adjusted odds ratio 1.5; 95% confidence interval 1.2, 2.0). No other residency exposures were associated. Conclusions— Residents who anticipate high involvement in community pediatrics at the start of residency participate in related opportunities in training. Exposure to community settings during residency may encourage community involvement after training

Maternal Body Mass Index, Neighborhood Characteristics and Early Childhood Obesity

Objective: Childhood obesity is a leading cause of morbidity among US children with nearly 1 in 10 children ages 2 – 5 with a BMI greater than the 95th percentile. Childhood obesity is associated with multiple comorbidities including early-onset type II diabetes, sleep apnea, mood disorders, social marginalization and bullying. Moreover, obese children are more likely to become obese adults. Maternal pre-pregnancy BMI is one gestational exposure consistently associated with offspring obesity. Neighborhood characteristics, including socioeconomic deprivation and food environment, represent shared maternal-child exposures which have also been associated with child obesity. The objective of this thesis was to evaluate the association between maternal socio-demographic, pre-pregnancy health, pregnancy health and neighborhood characteristics and child BMI percentile at 5 years (aim 1) and BMI trajectory from 2 – 8 years (aim 2). Methods: The study sample was drawn from the Delaware Mother and Baby Cohort (DMBC), a prospective cohort of 4,852 women who delivered at Christiana Care Health System (CCHS) in Newark, Delaware between January 1, 2004 and December 31, 2007; and who accessed pediatric care for their child through the Nemours Children’s Health System (NCHS) at least once between January 1, 2004 and May 31, 2011. The DMBC was linked with Delaware birth certificates, the 2010 US Census and the Delaware Healthy Toolkit Food Resource Database. The primary dependent variables were age- and sex- standardized BMI percentile at age 5 (aim 1) and rate of change in BMI (kg/m2/month) from 2 - 8 years (aim 2). The main independent variables included maternal pre-pregnancy BMI, neighborhood socioeconomic deprivation and distance between mother’s residence and closest healthy food outlet. Associations found in bivariable analyses informed multivariable modeling. Multivariable multinomial logistic regression was performed to identify the independent influence of maternal pre-pregnancy BMI, neighborhood food environment and census-tract socioeconomic deprivation on child BMI percentile at 5-years and BMI trajectory from 2 to 8 years after adjusting for other covariables. For all analyses, p-values < 0.05 were considered statistically significant. All analyses were performed using Stata/IC Version 13.0 and Comprehensive R Archive Network (R) Version 3.4.2. This study was approved by the Christiana Care Health System and University of Wisconsin – Madison Institutional Review Boards. Results: A total of 3,101 (63.9%) of DMBC participants met inclusion criteria for aim 1 and 3,862 (79.6%) of DMBC participants met inclusion criteria for aim 2. The sample characteristics were similar for both study aims; one-quarter of DMBC women had a pre-pregnancy BMI ≥ 30 kg/m2, one-quarter of dyads lived < 0.5 miles from the nearest healthy food outlet and 35% of participants resided in census-tracts with extreme socioeconomic deprivation. In multivariable models, maternal pre-pregnancy BMI was strongly associated with overweight and obesity at 5-years as well as steady and rapid gain BMI trajectory from 2 – 8 years old; it was not associated with a declining BMI trajectory. Children who resided in communities characterized by extreme socio-economic deprivation had significantly higher odds of obesity at 5-years than their counterparts in less deprived communities but proximity to healthy food outlets was not associated with child BMI at 5-years. Neither census-tract socio-economic deprivation nor neighborhood food environment was associated with child BMI trajectory. Conclusions: The odds of childhood obesity at 5-years and steady or rapid childhood BMI gain from 2 – 8 years were independently associated with maternal pre-pregnancy obesity after adjusting for maternal socio-demographic, pre-pregnancy health, pregnancy health and community characteristics. BMI at age 5 but not BMI trajectory was independently associated with neighborhood census-tract socioeconomic deprivation. Local food environment was not associated with child BMI or BMI trajectory. Children of obese women carry the highest odds of obesity in early childhood. Additional research is needed to better understand the association between neighborhood characteristics and early childhood BMI among offspring of obese and non-obese mothers