Racial and ethnic disparities in outcomes through 1 year of life in infants born prematurely: a population based study in California.

OBJECTIVES: To investigate racial/ethnic differences in rehospitalization and mortality rates among premature infants over the first year of life. STUDY DESIGN: A retrospective cohort study of infants born in California from 2011 to 2017 (n = 3,448,707) abstracted from a California Office of Statewide Health Planning and Development database. Unadjusted Kaplan-Meier tables and logistic regression controlling for health and sociodemographic characteristics were used to predict outcomes by race/ethnicity. RESULTS: Compared to White infants, Hispanic and Black early preterm infants were more likely to be readmitted; Black late/moderate preterm (LMPT) infants were more likely to be readmitted and to die after discharge; Hispanic and Black early preterm infants with BPD were more likely to be readmitted; Black LMPT infants with RDS were more likely to be readmitted and die after discharge. CONCLUSIONS: Racial/ethnic disparities in readmission and mortality rates exist for premature infants across several co-morbidities. Future studies are needed to improve equitability of outcomes.

Preterm birth and nativity among Black women with gestational diabetes in California, 2013-2017: a population-based retrospective cohort study.

BACKGROUND: Despite the disproportionate prevalence of gestational diabetes (GDM) and preterm birth (PTB) and their associated adverse perinatal outcomes among Black women, little is known about PTB among Black women with GDM. Specifically, the relationship between PTB by subtype (defined as indicated PTB and spontaneous PT labor) and severity, GDM, and nativity has not been well characterized. Here we examine the risk of PTB by severity (early < 34 weeks, late 34 to 36 weeks) and early term birth (37 to 38 weeks) by nativity among Black women with GDM in California. METHODS: This retrospective cohort study used linked birth certificate and hospital discharge data for 8609 of the 100,691 self-identifying non-Hispanic Black women with GDM who had a singleton live birth between 20 and 44 weeks gestation in California in 2013-2017. Adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were examine risks for PTB, by severity and subtype, and early term birth using multivariate regression modeling. RESULTS: Approximately, 83.9% of Black women with GDM were US-born and 16.1% were foreign-born. The overall prevalence of early PTB, late PTB, and early term birth was 3.8, 9.5, and 29.9%, respectively. Excluding history of prior PTB, preeclampsia was the greatest overall risk factor for early PTB (cOR = 6.7, 95%, CI 5.3 to 8.3), late PTB (cOR = 4.3, 95%, CI 3.8 to 5.0), and early term birth (cOR = 1.8, 95%, CI 1.6 to 2.0). There was no significant difference in the prevalence of PTB by subtypes and nativity (p = 0.5963). Overall, 14.2% of US- compared to 8.9% of foreign-born women had a PTB (early PTB: aOR = 0.56, 95%, CI 0.38 to 0.82; late PTB: aOR = 0.57, 95%, CI 0.45 to 0.73; early term birth: aOR = 0.67, 95%, CI 0.58 to 0.77). CONCLUSIONS: Foreign-born status remained protective of PTB, irrespective of severity and subtype. Preeclampsia, PTB, and GDM share pathophysiologic mechanisms suggesting a need to better understand differences in perinatal stress, chronic disease, and vascular dysfunction based on nativity in future epidemiologic studies and health services research.

Environmental and Socioeconomic Factors Influence the Live-Born Incidence of Congenital Heart Disease: A Population-Based Study in California.

BACKGROUND The development of congenital heart disease (CHD) is multifactorial with genetic and environmental influences. We sought to determine the relationship between socioeconomic and environmental factors with the incidence of CHD among live-born infants in California and to determine whether maternal comorbidities are in the causal pathway. METHODS AND RESULTS This was a population-based cohort study in California (2007-2012). The primary outcome was having significant CHD. Predictors included socioeconomic status and environmental exposure to pollutants determined by U.S. Census data. A social deprivation index and environmental exposure index was assigned based on neighborhood socioeconomic variables, categorized into 4 quartiles. Quartile 1 was the best with the least exposure to pollutants and social deprivation, and quartile 4 was the worst. Multivariate logistic regression and mediation analyses were performed. Among 2 419 651 live-born infants, the incidence of CHD was 3.2 per 1000 live births. The incidence of CHD was significantly higher among those in quartile 4 compared with quartile 1 (social deprivation index: 0.35% versus 0.29%; odds ratio [OR], 1.31; 95% CI, 1.21-1.41; environmental exposure index: 0.35% versus 0.29%; OR, 1.23; 95% CI, 1.15-1.31) after adjusting for maternal race/ethnicity and age and accounting for the relationship between the 2 primary predictors. Maternal comorbidities explained 13% (95% CI, 10%-20%) of the relationship between social deprivation index and environmental exposure index with the incidence of CHD. CONCLUSIONS Increased social deprivation and exposure to environmental pollutants are associated with the incidence of live-born CHD in California. Maternal comorbidities explain some, but not all, of this relationship. These findings identify targets for social policy initiatives to minimize health disparities.

Association of Revised WIC Food Package With Perinatal and Birth Outcomes: A Quasi-Experimental Study.

IMPORTANCE: The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) serves more than one-quarter of pregnant and postpartum women. In October 2009, the WIC food package underwent revisions to improve nutritional content. No studies have investigated the downstream effects of this revision on maternal and infant health. OBJECTIVE: To investigate whether the revised WIC food package improved perinatal and birth outcomes among recipients. DESIGN, SETTING, AND PARTICIPANTS: We conducted a quasi-experimental difference-in-differences analysis, comparing WIC recipients (the treatment group) before and after the package revisions while accounting for temporal trends among nonrecipients (the control group). Multivariable linear regressions were adjusted for sociodemographic covariates. This study was conducted using linked birth certificate and hospital discharge data from California from January 2007 to December 2012. Analysis began July 2018. EXPOSURES: Whether pregnant women received the revised WIC package, which included more whole grains, fruit, vegetables, and low-fat milk. MAIN OUTCOMES AND MEASURES: Measures of maternal and infant health, including maternal preeclampsia, gestational diabetes, and gestational weight gain as well as infant gestational age, birth weight, and hospitalizations. RESULTS: The sample included 2 897 537 infants born to 2 441 658 mothers. WIC recipients were more likely to be Hispanic, less educated, of greater parity, and younger than nonrecipients. The revised WIC food package was associated with reductions in maternal preeclampsia (-0.6% points; 95% CI, -0.8 to -0.4) and more than recommended gestational weight gain (-3.2% points; 95% CI, -3.6 to -2.7), increased likelihood of as recommended (2.3% points; 95% CI, 1.8 to 2.8) and less than recommended (0.9% points; 95% CI, 0.5 to 1.2) gestational weight gain, and longer gestational age (0.2 weeks; 95% CI, 0.001 to 0.034). Among infants, an increased likelihood of birth weight that was appropriate for gestational age was observed (0.9% points; 95% CI, 0.5 to 1.3). Although birth weight itself was reduced (-0.009 SDs; 95% CI, -0.016 to -0.001), this was accompanied by reductions in small for gestational age (-0.4% points; 95% CI, -0.7 to -0.1), large for gestational age (-0.5% points; 95% CI, -0.8 to -0.2), and low-birth-weight infants (-0.2% points; 95% CI, -0.4 to -0.004), suggesting that the revised food package improved distributions of birth weight. CONCLUSIONS AND RELEVANCE: The revised WIC food package, intended to improve women's nutrition during pregnancy, was associated with beneficial impacts on maternal and child health. This suggests that WIC policy may be an important lever to reduce health disparities among high-risk women and children at a critical juncture in the life course.

Maternal factors influencing late entry into prenatal care: a stratified analysis by race or ethnicity and insurance status.

Objective: Examine factors influencing late (> sixth month of gestation) entry into prenatal care by race/ethnicity and insurance payer. Methods: The study population was drawn from singleton live births in California from 2007 to 2012 in the birth cohort file maintained by the California Office of Statewide Health Planning and Development, which includes linked birth certificate and mother and infant hospital discharge records. The sample was restricted to infants delivered between 20 and 44 weeks gestation. Logistic regression was used to calculate relative risks (RR) and 95% confidence intervals (CI) for factors influencing late entry into prenatal care. Maternal age, education, smoking, drug or alcohol abuse/dependence, mental illness, participation in the Women, Infants and Children's program and rural residence were evaluated for women entering prenatal care > sixth month of gestation compared with women entering < fourth month. Backwards stepwise logistic regression was used to create final multivariable models of risk and protective factors for late prenatal care entry for each race or ethnicity and insurance payer. Results: The sample included 2,963,888 women. The percent of women with late entry into prenatal care was consistently higher among women with public versus private insurance. Less than 1% of white non-Hispanic and Asian women with private insurance entered prenatal care late versus more than 4% of white non-Hispanic and black women with public insurance. After stratifying by race or ethnicity and insurance status, women less than 18 years of age were more likely to enter prenatal care late, with young Asian women with private insurance at the highest risk (15.6%; adjusted RR 7.4, 95%CI 5.3-10.5). Among all women with private insurance, > 12-year education or age >34 years at term reduced the likelihood of late prenatal care entry (adjusted RRs 0.5-0.7). Drugs and alcohol abuse/dependence and residing in a rural county were associated with increased risk of late prenatal care across all subgroups (adjusted RRs 1.3-3.8). Participation in the Women, Infants, and Children's program was associated with decreased risk of late prenatal care for women with public insurance (adjusted RRs 0.6-0.7), but increased risk for women with private insurance (adjusted RRs 1.4-2.1). Conclusions: The percent of women with late entry into prenatal care was consistently higher among women with public insurance. Younger women, women with <12-year education, those who used drugs or alcohol or resided in rural counties were more likely to enter prenatal care late, with Asian women <18 years at especially high risk. Participation in the Women, Infants, and Children's program and maternal age >34 years at delivery increased the likelihood of late prenatal care for some subgroups of women and decreased the likelihood for others. These findings can inform institutional factors influencing late prenatal care, especially among lower income women, and may assist efforts aimed at encouraging earlier entry into prenatal care. Rationale: Optimal prenatal care includes initiation before the 14th week of gestation. Beginning care in the first trimester provides an opportunity for sonographic pregnancy dating or confirmation with best accuracy, which can later prove critical for management of preterm labor, maternal or fetal complications, or prolonged pregnancy. In order to improve maternal and infant health by increasing the number of women seeking prenatal care in the first trimester, it is important to examine the drivers for late entry. Here, we examine factors influencing late (> sixth month of gestation) entry into prenatal care by race/ethnicity and insurance payer. We found the percent of women with late entry into prenatal care was consistently higher among women with public insurance. Younger women, women with <12-year education, those who used drugs or alcohol or resided in rural counties were more likely to enter prenatal care late, with Asian women <18 years at especially high risk. These findings can inform institutional factors influencing late prenatal care, especially among lower income women, and may assist efforts aimed at encouraging earlier entry into prenatal care.

Using Index of Concentration at the Extremes as Indicators of Structural Racism to Evaluate the Association with Preterm Birth and Infant Mortality-California, 2011-2012.

Disparities in adverse birth outcomes for Black women continue. Research suggests that societal factors such as structural racism explain more variation in adverse birth outcomes than individual-level factors and societal poverty alone. The Index of Concentration at the Extremes (ICE) measures spatial social polarization by quantifying extremes of deprived and privileged social groups using a single metric and has been shown to partially explain racial disparities in black carbon exposures, mortality, fatal and non-fatal assaults, and adverse birth outcomes such as preterm birth and infant mortality. The objective of this analysis was to assess if local measures of racial and economic segregation as proxies for structural racism are associated and preterm birth and infant mortality experienced by Black women residing in California. California birth cohort files were merged with the American Community Survey by zip code (2011-2012). The ICE was used to quantify privileged and deprived groups (i.e., Black vs. White; high income vs. low income; Black low income vs. White high income) by zip code. ICE scores range from - 1 (deprived) to 1 (privileged). ICE scores were categorized into five quintiles based on sample distributions of these measures: quintile 1 (least privileged)-quintile 5 (most privileged). Generalized linear mixed models were used to test the likelihood that ICE measures were associated with preterm birth or with infant mortality experienced by Black women residing in California. Black women were most likely to reside in zip codes with greater extreme income concentrations, and moderate extreme race and race + income concentrations. Bivariate analysis revealed that greater extreme income, race, and race + income concentrations increased the odds of preterm birth and infant mortality. For example, women residing in least privileged zip codes (quintile 1) were significantly more likely to experience preterm birth (race + income ICE OR = 1.31, 95% CI = 1.72-1.46) and infant mortality (race + income ICE OR = 1.70, 95% CI = 1.17-2.47) compared to women living in the most privileged zip codes (quintile 5). Adjusting for maternal characteristics, income, race, and race + income concentrations remained negatively associated with preterm birth. However, only race and race + income concentrations remained associated with infant mortality. Findings support that ICE is a promising measure of structural racism that can be used to address racial disparities in preterm birth and infant mortality experienced by Black women in California.

Socioeconomic Mediators of Racial and Ethnic Disparities in Congenital Heart Disease Outcomes: A Population-Based Study in California.

Background Racial/ethnic and socioeconomic disparities exist in outcomes for children with congenital heart disease. We sought to determine the influence of race/ethnicity and mediating socioeconomic factors on 1-year outcomes for live-born infants with hypoplastic left heart syndrome and dextro-Transposition of the great arteries. Methods and Results The authors performed a population-based cohort study using the California Office of Statewide Health Planning and Development database. Live-born infants without chromosomal anomalies were included. The outcome was a composite measure of mortality or unexpected hospital readmissions within the first year of life defined as >3 (hypoplastic left heart syndrome) or >1 readmissions (dextro-Transposition of the great arteries). Hispanic ethnicity was compared with non-Hispanic white ethnicity. Mediation analyses determined the percent contribution to outcome for each mediator on the pathway between race/ethnicity and outcome. A total of 1796 patients comprised the cohort (n=964 [hypoplastic left heart syndrome], n=832 [dextro-Transposition of the great arteries]) and 1315 were included in the analysis (n=477 non-Hispanic white, n=838 Hispanic). Hispanic ethnicity was associated with a poor outcome (crude odds ratio, 1.72; 95% confidence interval [CI], 1.37-2.17). Higher maternal education (crude odds ratio 0.5; 95% CI , 0.38-0.65) and private insurance (crude odds ratio, 0.65; 95% CI , 0.45-0.71) were protective. In the mediation analysis, maternal education and insurance status explained 33.2% (95% CI , 7-66.4) and 27.6% (95% CI , 6.5-63.1) of the relationship between race/ethnicity and poor outcome, while infant characteristics played a minimal role. Conclusions Socioeconomic factors explain a significant portion of the association between Hispanic ethnicity and poor outcome in neonates with critical congenital heart disease. These findings identify vulnerable populations that would benefit from resources to lessen health disparities.

Racial and Ethnic Disparities in Preterm Infant Mortality and Severe Morbidity: A Population-Based Study.

BACKGROUND: Disparities exist in the rates of preterm birth and infant mortality across different racial/ethnic groups. However, only a few studies have examined the impact of race/ethnicity on the outcomes of premature infants. OBJECTIVE: To report the rates of mortality and severe neonatal morbidity among multiple gestational age (GA) groups stratified by race/ethnicity. METHODS: A retrospective cohort study utilizing linked birth certificate, hospital discharge, readmission, and death records up to 1 year of life. Live-born infants ≤36 weeks born in the period 2007-2012 were included. Maternal self-identified race/ethnicity, as recorded on the birth certificate, was used. ICD-9 diagnostic and procedure codes captured neonatal morbidities (intraventricular hemorrhage, retinopathy of prematurity, periventricular leukomalacia, bronchopulmonary dysplasia, and necrotizing enterocolitis). Multiple logistic regression was performed to evaluate the impact of race/ethnicity on mortality and morbidity, adjusting for GA, birth weight, sex, and multiple gestation. RESULTS: Our cohort totaled 245,242 preterm infants; 26% were white, 46% Hispanic, 8% black, and 12% Asian. At 22-25 weeks, black infants were less likely to die than white infants (odds ratio [OR] 0.76; 95% confidence interval [CI] 0.62-0.94). However, black infants born at 32-34 weeks (OR 1.64; 95% CI 1.15-2.32) or 35-36 weeks (OR 1.57; 95% CI 1.00-2.24) were more likely to die. Hispanic infants born at 35-36 weeks were less likely to die than white infants (OR 0.66; 95% CI 0.50-0.87). Racial disparities at different GAs were also detected for severe morbidities. CONCLUSIONS: The impact of race/ethnicity on mortality and severe morbidity varied across GA categories in preterm infants. Disparities persisted even after adjusting for important potential confounders.

High quality genome-wide genotyping from archived dried blood spots without DNA amplification.

Spots of blood are routinely collected from newborn babies onto filter paper called Guthrie cards and used to screen for metabolic and genetic disorders. The archived dried blood spots are an important and precious resource for genomic research. Whole genome amplification of dried blood spot DNA has been used to provide DNA for genome-wide SNP genotyping. Here we describe a 96 well format procedure to extract DNA from a portion of a dried blood spot that provides sufficient unamplified genomic DNA for genome-wide single nucleotide polymorphism (SNP) genotyping. We show that SNP genotyping of the unamplified DNA is more robust than genotyping amplified dried blood spot DNA, is comparable in cost, and can be done with thousands of samples. This procedure can be used for genome-wide association studies and other large-scale genomic analyses that require robust, high-accuracy genotyping of dried blood spot DNA.