A spatial analysis of birth defects in Texas, 1999-2011

Temporal Trends of Neonatal Surgical Conditions in Texas and Accessibility to Pediatric Surgical Care

INTRODUCTION

Texas consistently accounts for approximately 10% of annual national births, the second highest of all US states. This temporal study aimed to evaluate incidences of neonatal surgical conditions across Texas and to delineate regional pediatric surgeon accessibility.

METHODS

The Texas Birth Defects Registry was queried from 1999 to 2018, based on 11 well-established regions. Nine disorders (30,476 patients) were identified as being within the operative scope of pediatric surgeons: biliary atresia (BA), pyloric stenosis (PS), Hirschsprung's disease, stenosis/atresia of large intestine/rectum/anus, stenosis/atresia of small intestine, tracheoesophageal fistula/esophageal atresia, gastroschisis, omphalocele, and congenital diaphragmatic hernia. Annual and regional incidences were compared (/10,000 births). Statewide pediatric surgeons were identified through the American Pediatric Surgical Association directory. Regional incidences of neonatal disorder per surgeon were evaluated from 2010 to 2018 as a surrogate for provider disparity.

RESULTS

PS demonstrated the highest incidence (14.405/10,000), while BA had the lowest (0.707/10,000). Overall, incidences of PS and BA decreased significantly, while incidences of Hirschsprung's disease and small intestine increased. Other diagnoses remained stable. Regions 2 (48.24/10,000) and 11 (47.79/10,000) had the highest incidence of neonatal conditions; Region 6 had the lowest (34.68/10,000). Three rural regions (#2, 4, 9) lacked pediatric surgeons from 2010 to 2018. Of regions with at least one surgeon, historically underserved regions (#10, 11) along the Texas-Mexico border consistently had the highest defect per surgeon rates.

CONCLUSIONS

There are temporal and regional differences in incidences of neonatal conditions treated by pediatric surgeons across Texas. Improving access to neonatal care is a complex issue that necessitates collaborative efforts between state legislatures, health systems, and providers.

Unmatched spatially stratified controls: A simulation study examining efficiency and precision using spatially-diverse controls and generalized additive models

Unmatched spatially stratified random sampling (SSRS) of non-cases selects geographically balanced controls by dividing the study area into spatial strata and randomly selecting controls from all non-cases within each stratum. The performance of SSRS control selection was evaluated in a case study spatial analysis of preterm birth in Massachusetts. In a simulation study, we fit generalized additive models using controls selected by SSRS or simple random sample (SRS) designs. We compared mean squared error (MSE), bias, relative efficiency (RE), and statistically significant map results to the model results with all non-cases. SSRS designs had lower average MSE (0.0042-0.0044) and higher RE (77-80%) compared to SRS designs (MSE: 0.0072-0.0073; RE across designs: 71%). SSRS map results were more consistent across simulations, reliably identifying statistically significant areas. SSRS designs improved efficiency by selecting controls that are geographically distributed, particularly from low population density areas, and may be more appropriate for spatial analyses.

The medical and surgical management of gastroschisis

Gastroschisis (GS) is a full-thickness abdominal wall defect in which fetal intestine herniates alongside the umbilical cord into the intrauterine cavity, resulting in an intestinal injury of variable severity. An increased prevalence of gastroschisis has been observed across several continents and is a focus of epidemiologic study. Prenatal diagnosis of GS is common and allows for delivery planning and treatment in neonatal intensive care units (NICUs) by collaborative interdisciplinary teams (neonatology, neonatal nursing and pediatric surgery). Postnatal treatment focuses on closure of the defect, optimized nutrition, complication avoidance and a timely transition to enteral feeding. Babies born with complex GS are more vulnerable to complications, have longer and more resource intensive hospital stays and benefit from standardized care pathways provided by teams with expertise in managing infants with intestinal failure. This article will review the current state of knowledge related to the medical and surgical management and outcomes of gastroschisis with a special focus on the role of the neonatologist in supporting integrated team-based care.