County-Level Maternal Vulnerability and Preterm Birth in the US.

2023

e2315306

05/2023

2574-3805

IMPORTANCE: Appreciation for the effects of neighborhood conditions and community factors on perinatal health is increasing. However, community-level indices specific to maternal health and associations with preterm birth (PTB) have not been assessed.

OBJECTIVE: To examine the association of the Maternal Vulnerability Index (MVI), a novel county-level index designed to quantify maternal vulnerability to adverse health outcomes, with PTB.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used US Vital Statistics data from January 1 to December 31, 2018. Participants included 3 659 099 singleton births at 22 plus 0/7 to 44 plus 6/7 weeks of gestation born in the US. Analyses were conducted from December 1, 2021, through March 31, 2023.

EXPOSURE: The MVI, a composite measure of 43 area-level indicators, categorized into 6 themes reflecting physical, social, and health care landscapes. Overall MVI and theme were stratified by quintile (very low to very high) by maternal county of residence.

MAIN OUTCOMES AND MEASURES: The primary outcome was PTB (gestational age <37 weeks). Secondary outcomes were PTB categories: extreme (gestational age ≤28 weeks), very (gestational age 29-31 weeks), moderate (gestational age 32-33 weeks), and late (gestational age 34-36 weeks). Multivariable logistic regression quantified associations of MVI, overall and by theme, with PTB, overall and by PTB category.

RESULTS: Among 3 659 099 births, 298 847 (8.2%) were preterm (male, 51.1%; female, 48.9%). Maternal race and ethnicity included 0.8% American Indian or Alaska Native, 6.8% Asian or Pacific Islander, 23.6% Hispanic, 14.5% non-Hispanic Black, 52.1% non-Hispanic White, and 2.2% with more than 1 race. Compared with full-term births, MVI was higher for PTBs across all themes. Very high MVI was associated with increased PTB in unadjusted (odds ratio [OR], 1.50 [95% CI, 1.45-1.56]) and adjusted (OR, 1.07 [95% CI, 1.01-1.13]) analyses. In adjusted analyses of PTB categories, MVI had the largest association with extreme PTB (adjusted OR, 1.18 [95% CI, 1.07-1.29]). Higher MVI in the themes of physical health, mental health and substance abuse, and general health care remained associated with PTB overall in adjusted models. While the physical health and socioeconomic determinant themes were associated with extreme PTB, physical health, mental health and substance abuse, and general health care themes were associated with late PTB.

CONCLUSIONS AND RELEVANCE: The findings of this cohort study suggest that MVI was associated with PTB even after adjustment for individual-level confounders. The MVI is a useful measure for county-level PTB risk that may have policy implications for counties working to lower preterm rates and improve perinatal outcomes.

10.1001/jamanetworkopen.2023.15306

JAMA Netw Open

37227724

Addressing Maternal Mortality in the US-A Pediatrics Responsibility.

2023

05/2023

1538-3598

10.1001/jama.2023.6234

JAMA

37155191

Assessing Racial Residential Segregation as a Risk Factor for Severe Maternal Morbidity.

2023

05/2023

1873-2585

PURPOSE: To measure associations of area-level racial and economic residential segregation with severe maternal morbidity (SMM).

METHODS: We conducted a retrospective cohort study of births at two Philadelphia hospitals between 2018-2020 to analyze associations of segregation, quantified using the Index of Concentration at the Extremes (ICE), with SMM. We used stratified multivariable, multilevel, logistic regression models to determine whether associations of ICE with SMM varied by self-identified race or hospital catchment.

RESULTS: Of the 25,979 patients (44.1% Black, 35.8% White), 1,381 (5.3%) had SMM (Black [6.1%], White [4.4%]). SMM was higher among patients residing outside (6.3%), then inside, (5.0%) Philadelphia (P<0.001). Overall, ICE was not associated with SMM. However, ICE (higher proportion of White vs. Black households) was associated with lower odds of SMM among patients residing inside Philadelphia (aOR 0.87, 95% CI: 0.80-0.94) and higher odds outside Philadelphia (aOR 1.12, 95% CI: 0.95-1.31). Moran's I indicated spatial autocorrelation of SMM overall (P<0.001); when stratified, autocorrelation was only evident outside Philadelphia.

CONCLUSIONS: Overall, ICE was not associated with SMM. However, higher ICE was associated with lower odds of SMM among Philadelphia residents. Findings highlight the importance of hospital catchment area and referral patterns in spatial analyses of hospital datasets.

10.1016/j.annepidem.2023.04.018

Ann Epidemiol

37146923

Resilience as a potential modifier of racial inequities in preterm birth.

2023

04/2023

1873-2585

PURPOSE: In the United States, preterm birth is 55% more common among Black compared to White individuals and psychosocial stressors may contribute. Resilience is associated with improved health outcomes outside of pregnancy. However, whether resilience modifies preterm birth inequity is unknown. We hypothesized that high resilience would reduce inequities in preterm birth risk.

METHODS: This study analyzes data from 535 pregnancies among Black (n=101, 19%) and White (n=434, 81%) participants from the Spontaneous Prematurity and Epigenetics of the Cervix prospective cohort. Participants completed the Connor-Davidson Resilience Scale. We calculated risk ratios (RR) for preterm birth among Black compared to White participants, stratified by resilience tertiles, to test for effect measure modification.

RESULTS: Among those in the lowest resilience tertile, there were 6 (20.7%) preterm births among Black and 7 (4.9%) among White participants (RR: 4.26; 95% confidence interval (CI): 1.53, 11.81). Among those in the highest resilience tertile, there were 8 (18.2%) preterm births among Black and 14 (9.5%) among White participants (RR: 1.92; 95% CI: 0.87, 4.24. Adjusting for education and income, the Black:White RR was 2.00 (95% CI 0.47, 8.64) in the lowest tertile, and 3.49 (95% CI 1.52, 8.01) in the highest tertile.

CONCLUSIONS: Black-White preterm birth inequity did not differ among resilience strata and remained significant in the highest tertile. Our findings suggest that high resilience is inadequate to overcome Black:White racial inequity in preterm birth.

10.1016/j.annepidem.2023.04.010

Ann Epidemiol

37088321

Variation in NICU Head CT Utilization Among U.S. Children's Hospitals.

2023

106-141

02/2023

2154-1671

OBJECTIVES: Evaluate nationwide 12-year trend and hospital-level variation in head computed tomography (CT) utilization among infants admitted to pediatric hospital NICUs. We hypothesized there was significant variation in utilization.

METHODS: We conducted a retrospective cohort study examining head CT utilization for infants admitted to the NICU within 31 United States children's hospitals within the Pediatric Health Information System database between 2010 and 2021. Mixed effects logistic regression was used to estimate head CT, head MRI, and head ultrasound utilization (% of admissions) by year. Risk-adjusted hospital head CT rates were examined within the 2021 cohort.

RESULTS: Between 2010 and 2021, there were 338 644 NICU admissions, of which 10 052 included head CT (3.0%). Overall, head CT utilization decreased (4.9% in 2010 to 2.6% in 2021, P < .0001), with a concomitant increase in head MRI (12.1% to 18.7%, P < .0001) and head ultrasound (41.3% to 43.4%, P < .0001) utilization. In 2021, significant variation in risk-adjusted head CT utilization was noted across centers, with hospital head CT rates ranging from 0% to 10% of admissions. Greatest hospital-level variation was noted for patients with codes for seizure or encephalopathy (hospital head CT rate interquartile range [IQR] = 11.6%; 50th percentile = 12.0%), ventriculoperitoneal shunt (IQR = 10.8%; 50th percentile = 15.4%), and infection (IQR = 10.1%; 50th percentile = 7.5%).

CONCLUSIONS: Head CT utilization within pediatric hospital NICUs has declined over the past 12-years, but substantial hospital-level variation remains. Development of CT stewardship guidelines may help decrease variation and reduce infant radiation exposure.

10.1542/hpeds.2021-006322

Hosp Pediatr

36617983

Associations of gestational exposure to organophosphate esters with gestational age and neonatal anthropometric measures: The HOME study.

2023

120516

01/2023

1873-6424

Organophosphate esters (OPEs) are developmental toxicants in experimental studies of animals, but limited evidence is available in humans. We included 340 mother-infant pairs in the Health Outcomes and Measures of the Environment (HOME) Study (Cincinnati, Ohio, USA) for the analysis. We evaluated gestational exposure to OPEs with gestation age at birth and newborn anthropometric measures. We quantified four OPE urinary metabolites at 16 weeks and 26 weeks of gestation. We extracted gestational age at birth, newborn weight, length, and head circumference from the chart review. We calculated z-scores for these anthropometric measures and the ponderal index. We used multiple informant models to examine the associations between repeated OPE measurements and the outcomes. We used modified Poisson regression to estimate the association of gestational exposure to OPEs with preterm birth. We also explored effect modification by infant sex and the potential mediation effect by the highest maternal blood pressure and glucose levels. We found that bis(2-chloroethyl) phosphate (BCEP) at 16 weeks and diphenyl phosphate at 26 weeks of pregnancy were positively associated with gestational age and inversely associated with preterm birth. In female newborns, BCEP at 16 weeks was inversely related to birth weight and length z-scores. In male newborns, we observed negative associations of 26-week di-n-butyl phosphate with the ponderal index at birth. No mediation by the highest maternal blood pressure or glucose levels during pregnancy was identified. In this cohort, gestational exposure to some OPEs was associated with gestational age, preterm birth, and neonatal anthropometric measures. Certain associations tended to be window- and infant sex-specific.

10.1016/j.envpol.2022.120516

Environ Pollut

36341822

Bringing postpartum care to the NICU-An opportunity to improve health in a high-risk obstetric population.

2023

1-2

01/2023

1476-5543

10.1038/s41372-022-01525-z

J Perinatol

36198771

Variation in NICU Head CT Utilization Among U.S. Children's Hospitals.

2023

01/2023

2154-1671

OBJECTIVES: Evaluate nationwide 12-year trend and hospital-level variation in head computed tomography (CT) utilization among infants admitted to pediatric hospital NICUs. We hypothesized there was significant variation in utilization.

METHODS: We conducted a retrospective cohort study examining head CT utilization for infants admitted to the NICU within 31 United States children's hospitals within the Pediatric Health Information System database between 2010 and 2021. Mixed effects logistic regression was used to estimate head CT, head MRI, and head ultrasound utilization (% of admissions) by year. Risk-adjusted hospital head CT rates were examined within the 2021 cohort.

RESULTS: Between 2010 and 2021, there were 338 644 NICU admissions, of which 10 052 included head CT (3.0%). Overall, head CT utilization decreased (4.9% in 2010 to 2.6% in 2021, P < .0001), with a concomitant increase in head MRI (12.1% to 18.7%, P < .0001) and head ultrasound (41.3% to 43.4%, P < .0001) utilization. In 2021, significant variation in risk-adjusted head CT utilization was noted across centers, with hospital head CT rates ranging from 0% to 10% of admissions. Greatest hospital-level variation was noted for patients with codes for seizure or encephalopathy (hospital head CT rate interquartile range [IQR] = 11.6%; 50th percentile = 12.0%), ventriculoperitoneal shunt (IQR = 10.8%; 50th percentile = 15.4%), and infection (IQR = 10.1%; 50th percentile = 7.5%).

CONCLUSIONS: Head CT utilization within pediatric hospital NICUs has declined over the past 12-years, but substantial hospital-level variation remains. Development of CT stewardship guidelines may help decrease variation and reduce infant radiation exposure.

10.1542/hpeds.2021-006322

Hosp Pediatr

36617983

Cervical microRNA expression and spontaneous preterm birth.

2023

100783

01/2023

2589-9333

BACKGROUND: Preterm birth remains a major public health issue affecting 10% of all pregnancies and increases risks of neonatal morbidity and mortality. Approximately 50% to 60% of preterm births are spontaneous, resulting from preterm premature rupture of membranes or preterm labor. The pathogenesis of spontaneous preterm birth is incompletely understood, and prediction of preterm birth remains elusive. Accurate prediction of preterm birth would reduce infant morbidity and mortality through targeted patient referral to hospitals equipped to care for preterm infants. Two previous studies have analyzed cervical microRNAs in association with spontaneous preterm birth and the length of gestation, but the extent to which microRNAs serve as predictive biomarkers remains unknown.

OBJECTIVE: This study aimed to examine associations between cervical microRNA expression and spontaneous preterm birth, with the specific goal of identifying a subset of microRNAs that predict spontaneous preterm birth.

STUDY DESIGN: We performed a prospective, nested, case-control study of 25 cases with spontaneous preterm birth and 49 term controls. Controls were matched to cases in a 2:1 ratio on the basis of age, parity, and self-identified race. Cervical swabs were collected at a mean gestational age of 17.1 (4.8) weeks of gestation, and microRNAs were analyzed using a quantitative polymerase chain reaction array. Normalized microRNA expression was compared between cases and controls, and a false discovery rate of 0.2 was applied to account for multiple comparisons. Histopathologic analysis of slides of cervical swab samples was performed to quantify leukocyte burden for adjustment in conditional regression models. We explored the use of Relief-based unsupervised identification of top microRNAs and support vector machines to predict spontaneous preterm birth. We performed microRNA enrichment analysis to explore potential biologic targets and pathways in which up-regulated microRNAs might be involved.

RESULTS: Of the 754 microRNAs on the polymerase chain reaction array, 346 were detected in ≥75% of participants' cervical swabs. Average cervical microRNA expression was significantly higher in cases of spontaneous preterm birth than in controls (P=.01). There were 95 significantly up-regulated individual microRNAs (>2-fold change) in cases of subsequent spontaneous preterm birth compared with term controls (P<.05; q<0.2). Notably, miR-143, miR-30e-3p, and miR-199b were all significantly up-regulated, which is consistent with the 1 previous study of cervical microRNA and spontaneous preterm birth. A Relief-based, novel variable (feature) selection machine learning approach had low-to-moderate prediction accuracy, with an area under the receiver operating curve of 0.71. Enrichment analysis revealed that identified microRNAs may modulate inflammatory cell signaling.

CONCLUSION: In this prospective nested case-control study of cervical microRNA expression and spontaneous preterm birth, we identified a global increase in microRNA expression and up-regulation of 95 distinct microRNAs in association with subsequent spontaneous preterm birth. Larger and more diverse studies are required to determine the ability of microRNAs to accurately predict spontaneous preterm birth, and mechanistic work to facilitate development of novel therapeutic interventions to prevent spontaneous preterm birth is warranted.

10.1016/j.ajogmf.2022.100783

Am J Obstet Gynecol MFM

36280145

Associations of gestational exposure to organophosphate esters with gestational age and neonatal anthropometric measures: The HOME study.

2022

120516

10/2022

1873-6424

Organophosphate esters (OPEs) are developmental toxicants in experimental studies of animals, but limited evidence is available in humans. We included 340 mother-infant pairs in the Health Outcomes and Measures of the Environment (HOME) Study (Cincinnati, Ohio, USA) for the analysis. We evaluated gestational exposure to OPEs with gestation age at birth and newborn anthropometric measures. We quantified four OPE urinary metabolites at 16 weeks and 26 weeks of gestation. We extracted gestational age at birth, newborn weight, length, and head circumference from the chart review. We calculated z-scores for these anthropometric measures and the ponderal index. We used multiple informant models to examine the associations between repeated OPE measurements and the outcomes. We used modified Poisson regression to estimate the association of gestational exposure to OPEs with preterm birth. We also explored effect modification by infant sex and the potential mediation effect by the highest maternal blood pressure and glucose levels. We found that bis(2-chloroethyl) phosphate (BCEP) at 16 weeks and diphenyl phosphate at 26 weeks of pregnancy were positively associated with gestational age and inversely associated with preterm birth. In female newborns, BCEP at 16 weeks was inversely related to birth weight and length z-scores. In male newborns, we observed negative associations of 26-week di-n-butyl phosphate with the ponderal index at birth. No mediation by the highest maternal blood pressure or glucose levels during pregnancy was identified. In this cohort, gestational exposure to some OPEs was associated with gestational age, preterm birth, and neonatal anthropometric measures. Certain associations tended to be window- and infant sex-specific.

10.1016/j.envpol.2022.120516

Environ Pollut

36341822