Distance from home to birth hospital, transfer, and mortality in neonates with hypoplastic left heart syndrome in California

Transfer Patterns Among Infants Born at 28 to 34 Weeks' Gestation

BACKGROUND

Although postnatal transfer patterns among high-risk (eg, extremely preterm or surgical) infants have been described, transfer patterns among lower-risk populations are unknown. The objective was to examine transfer frequency, indication, timing, and trajectory among very and moderate preterm infants.

METHODS

Observational study of the US Vermont Oxford Network all NICU admissions database from 2016 to 2021 of inborn infants 280/7 to 346/7 weeks. Infants' first transfer was assessed by gestational age, age at transfer, reason for transfer, and transfer trajectory.

RESULTS

Across 467 hospitals, 294 229 infants were eligible, of whom 12 552 (4.3%) had an initial disposition of transfer. The proportion of infants transferred decreased with increasing gestational age (9.6% [n = 1415] at 28 weeks vs 2.4% [n = 2646] at 34 weeks) as did the median age at time of transfer (47 days [interquartile range 30-73] at 28 weeks vs 8 days [interquartile range 3-16] at 34 weeks). The median post menstrual age at transfer was 34 or 35 weeks across all gestational ages. The most common reason for transfer was growth or discharge planning (45.0%) followed by medical and diagnostic services (30.2%), though this varied by gestation. In this cohort, 42.7% of transfers were to a higher-level unit, 10.2% to a same-level unit, and 46.7% to a lower-level unit, with indication reflecting access to specific services.

CONCLUSIONS

Over 4% of very and moderate preterm infants are transferred. In this population, the median age of transfer is later and does not reflect immediate care needs after birth, but rather the provision of risk-appropriate care.

Neonatal Depression Is Associated With 1-Year Mortality in Critical Congenital Heart Disease

Background Low 5-minute Apgar scores (AS) are predictive of term and preterm neonatal mortality but have not been well studied in the critical congenital heart disease (CCHD) population. We analyzed US national vital statistics data to evaluate the association between neonatal depression (AS 0-3) and 1-year mortality in CCHD. Methods and Results We performed a retrospective cohort study using 2014 to 2018 Centers for Disease Control and Prevention cohort-linked birth certificate and infant death records. Five-minute AS were categorized as ≤3, 4 to 6, or ≥7. We calculated birth rates and associated mortality rates by AS group in infants with and without CCHD. Multivariable logistic regression analyzed neonatal, maternal, and pregnancy-related risk factors for neonatal depression and 1-year mortality. Of 11 642 neonates with CCHD (0.06% of all births), the 5.8% with AS 0 to 3 accounted for 23.3% of all 1-year CCHD mortality, with 69.9% of deaths occurring within 1 month of life. Gestational age at birth, growth restriction, extracardiac defects, race, and low maternal education were associated with an increased odds of AS 0 to 3 in neonates with CCHD relative to those with AS 7 to 10 on multivariable analysis. AS 0 to 3 was associated with 1-year CCHD mortality after adjusting for these factors, prenatal care, and delivery location (adjusted odds ratio, 14.57 [95% CI, 11.73-18.10]). Conclusions The AS is a routine clinical measure providing important prognostic information in CCHD. These findings suggest that prenatal and perinatal factors, beyond those included in current risk stratification tools, are important for CCHD outcomes. Multidisciplinary collaboration to understand the pathophysiology underlying neonatal depression may help identify interventions to improve CCHD mortality rates.

Linked birth cohort files for perinatal health research: California as a model for methodology and implementation

PURPOSE

Rigorous perinatal epidemiologic research depends on population-based parental and neonatal sociodemographic and clinical data. Here we describe the creation of linked birth cohort files, an enriched data source that combines information from vital records with maternal delivery and infant hospital encounter records.

METHODS

Probabilistic linkage techniques were used to link vital records (i.e., birth and fetal death certificates) from the California Department of Public Health with hospital inpatient, ambulatory surgery and emergency department encounter data for mothers and infants from the California Department of Health Care Access and Information.

RESULTS

From 2012 to 2018, 95% of live birth records were successfully linked to maternal and newborn hospital records while 85% of fetal death records were linked to a maternal delivery record. Overall, 93% of postnatal hospital encounters of infants (i.e., <1 year old) were matched to a linked record.

CONCLUSIONS

The linked birth cohort files is a rich resource opening many possibilities for understanding perinatal health outcomes and opportunities for linkage to longitudinal, social determinant, and environmental data. To optimally use this file for research, analysts should evaluate possible shortcomings or biases of the data sources being linked.