Tuesday, September 8, 2015

Neurodevelopmental morbidity of late preterm and early term birth

NZ Rabie; TM Bird; EF Magann; RW Hall; SS McKelvey.  ADHD and Developmental Speech/Language Disorders in Late Preterm, Early Term and Term Infants. J Perinatol. 2015;35(8):660-664

Objective: We sought to compare the long-term neurodevelopmental outcomes of late preterm, early term and term infants while controlling for a wide range of maternal complications and comorbidities.
Study design: Data for the study was obtained from the South Carolina Medicaid claims and vital records databases from 1 January 2000 to 31 December 2003. We included infants weighing between 1500 and 4500 g, born between 34 0/7 and 41 6/7 weeks, and with no congenital anomalies. Outcome measures were based on the presence of ICD-9-CM codes for attention deficit hyperactivity disorders and developmental speech or language disorders.
Result: A total of 3270 late preterm (LPIs), 11 527 early term (ETIs) and 24 005 term infants met the eligibility criteria. Rates for all outcome variables were statistically significant and elevated for LPI, but adjusted hazard ratios (AHRs) were only significant for the risk of developmental speech and/or language delay (LPI: AHR 1.36 95% confidence interval (CI) 1.23 to 1.50; ETI: AHR 1.27 95% CI 1.17 to 1.37).
Conclusion: Late preterm and early term deliveries have adverse long-term neurodevelopmental outcomes, and these outcomes should be considered when determining the timing of delivery.

From the article:

Recently, however, there has been increased awareness of the problems associated with late preterm deliveries. In large part, the increased awareness is due to a 2005 national workshop that coined the term "late preterm" and focused on the morbidities and knowledge gaps of this segment of preterm births. A driving force for this workshop was the 31% increase in preterm births since 1981, with a large portion of this increase due to late preterm births. At this workshop, a late preterm birth was defined as occurring between 34 0/7 weeks and 36 6/7 weeks of gestation. These infants have increased morbidities, but the magnitude of the problem has not been well studied. In 2011, 71% of all preterm births (8.3% of all births) were late preterm, and these infants accounted for about 20 to 25% of neonatal intensive care unit admissions. It is well known that late preterm infants (LPI) have increased rates of short-term morbidities, including hypoglycemia, infection, respiratory distress syndrome, feeding difficulties and hyperbilirubinemia. The rates of long-term neurodevelopmental problems in LPI are less certain.

In addition to LPI, early term infants (ETIs)—defined as births occurring between 37 0/7 weeks and 38 6/7 weeks of gestation—also experience a higher rate of morbidity and mortality. ETIs have higher rates of respiratory distress syndrome and transient tachypnea of the newborn, and the American College of Obstetricians and Gynecologists recommends against elective deliveries before 39 weeks without medical indication or evidence of fetal lung maturity.

Identifying long-term outcomes attributable to early delivery is complicated by the fact that a variety of prenatal conditions, maternal risks and clinical practices may jointly influence both early delivery and subsequent adverse outcomes. Without controlling for these confounding factors, it is unclear whether ETIs and LPIs born of otherwise uncomplicated pregnancies are at any greater risk of long-term morbidity than term infants. The aim of the current study is to determine if there is an increased risk of neurodevelopmental problems with late preterm and early term deliveries, while controlling for a wide range of maternal complications and comorbidities...

There were 82 862 infants in the initial data set... A total of 77 763 infants were available for the first stage of the model and 38 802 infants were available for the second stage of the model.


NZ Rabie; TM Bird; EF Magann; RW Hall; SS McKelvey

No comments:

Post a Comment