T. Michael O’Shea

The Relationship between Early Concentrations of 25 Blood Proteins and Cerebral White Matter Injury in Preterm Newborns: The ELGAN Study

OBJECTIVE To evaluate whether concentrations of inflammation-related proteins are elevated in the blood of preterm newborns who develop cerebral white matter damage. STUDY DESIGN We measured 25 proteins in blood collected on days 1, 7, and 14 from 939 infants born before the 28th week of gestation. Brain ultrasound scans were read by at least two sonologists, who agreed on the presence or absence of lesions. A protein concentration was considered elevated if it was in the highest quartile for gestational age and the day on which the specimen was collected. RESULTS In time-oriented models, elevated concentrations of vascular endothelial growth factor receptor 1, serum amyloid A, and macrophage inflammatory protein 1β on day 1 and interleukin-8 on day 7 were associated with increased risk of ventriculomegaly. Elevated concentrations of macrophage inflammatory protein 1β on day 1 and intercellular adhesion molecule 1 on day 7 were associated with increased risk of an echolucent lesion. Infants with elevated concentrations of inflammation-related proteins on two separate days were at significantly increased risk for ventriculomegaly, but at only modestly increased risk for an echolucent lesion. CONCLUSIONS Concentrations of inflammation-related proteins in the circulation in the first days after preterm birth provide information about the risk of sonographic white matter damage. The inflammatory process might begin in utero.

Elevated Concentrations of Inflammation-Related Proteins in Postnatal Blood Predict Severe Developmental Delay at 2 Years of Age in Extremely Preterm Infants

OBJECTIVE To evaluate the hypothesis that elevated levels of inflammation-related proteins in early postnatal blood predict impaired mental and motor development in extremely preterm infants. STUDY DESIGN We measured concentrations of 25 inflammation-related proteins in blood collected on postnatal days 1, 7, and 14 from 939 infants born before 28 weeks gestation. An elevated level was defined as a concentration in the highest quartile for gestational age and day of blood collection. We identified impaired development at age 24 months using the Bayley Scales of Infant Development, Second Edition. The primary outcomes were scores on the Mental Scale or the Motor Scale of <55 (more than 3 SDs below the mean). RESULTS For 17 of the 25 inflammation-related proteins, 1 or more statistically significant associations (P<.01) was found between an elevated blood level of the protein and a developmental impairment. Elevations on multiple days were more often associated with developmental impairment than were elevations present for only 1 day. The highest number of predictive elevations was found in day-14 blood. CONCLUSION In extremely preterm infants, elevated levels of inflammation-related proteins in blood collected on postnatal days 7 and 14, especially when sustained, are associated with impaired mental and motor development at age 2 years.

Inflammation-initiating illnesses, inflammation-related proteins, and cognitive impairment in extremely preterm infants.

Neonatal inflammation is associated with perinatal brain damage. We evaluated to what extent elevated blood levels of inflammation-related proteins supplement information about the risk of impaired early cognitive function provided by inflammation-related illnesses. From 800 infants born before the 28th week of gestation, we collected blood spots on days 1, 7 and 14, for analysis of 25 inflammation-related proteins, and data about culture-positive bacteremia, necrotizing enterocolitis (Bell stage IIIb), and isolated perforation of the intestine, during the first two weeks, and whether they were ventilated on postnatal day 14. We considered a protein to be persistently or recurrently elevated if its concentration was in the top quartile (for gestational age and day blood was collected) on two separate days one week apart. We assessed the children at 2 years of age with the Bayley Mental Development Index (MDI). The combinations of NEC and ventilation on day 14, and of bacteremia and ventilation on day 14 consistently provided information about elevated risk of MDI <55, regardless of whether or not a variable for an elevated protein concentration was included in the model. A variable for a persistently or recurrently elevated concentration of each of the following proteins provided additional information about an increased risk of MDI <55: CRP, SAA, IL-6, TNF-alpha, IL-8, MIP-1beta, ICAM-1, E-SEL, and IGFBP-1. We conclude that elevated blood concentrations of inflammation-related proteins provide information about the risk of impaired cognitive function at age 2 years that supplements information provided by inflammation-associated illnesses.

Inflammation-related proteins in the blood of extremely low gestational age newborns. The contribution of inflammation to the appearance of developmental regulation

BACKGROUND We wanted to assess to what extent concentrations of circulating proteins appear to be developmentally regulated, and to what extent such regulation is influenced by intra-uterine inflammation. METHODS We measured 22 proteins in blood obtained on postnatal days 1, 7, and 14 from 818 children born before the 28th week of gestation for whom we also had information about placenta morphology. RESULTS Within the narrow gestational age range of this sample, some protein concentrations increase in blood with increasing gestational age. More commonly, the concentrations of inflammation-related proteins decrease with increasing gestational age. We observed this inverse pattern both in children whose placenta was and was not inflamed. CONCLUSIONS/INFERENCES: Regardless of whether or not the placenta is inflamed, the concentrations of inflammation-related proteins in early blood specimens appear to be developmentally regulated with the most common pattern being a decrease with increasing gestational age.

Systemic inflammation associated with mechanical ventilation among extremely preterm infants

Little evidence is available to document that mechanical ventilation is an antecedent of systemic inflammation in preterm humans. We obtained blood on postnatal day 14 from 726 infants born before the 28th week of gestation and measured the concentrations of 25 inflammation-related proteins. We created multivariable models to assess the relationship between duration of ventilation and protein concentrations in the top quartile. Compared to newborns ventilated for fewer than 7 days (N=247), those ventilated for 14 days (N=330) were more likely to have elevated blood concentrations of pro-inflammatory cytokines (IL-1β, TNF-α), chemokines (IL-8, MCP-1), an adhesion molecule (ICAM-1), and a matrix metalloprotease (MMP-9), and less likely to have elevated blood concentrations of two chemokines (RANTES, MIP-1β), a matrix metalloproteinase (MMP-1), and a growth factor (VEGF). Newborns ventilated for 7-13 days (N=149) had systemic inflammation that approximated the pattern of newborns ventilated for 14 days. These relationships were not confounded by chorioamnionitis or antenatal corticosteroid exposure, and were not altered appreciably among infants with and without bacteremia. These findings suggest that 2 weeks of ventilation are more likely than shorter durations of ventilation to be accompanied by high blood concentrations of pro-inflammatory proteins indicative of systemic inflammation, and by low concentrations of proteins that might protect from inflammation-mediated organ injury.

Respiratory outcomes of the surfactant positive pressure and oximetry randomized trial (SUPPORT).

OBJECTIVE To explore the early childhood pulmonary outcomes of infants who participated in the National Institute of Child Health and Human Developments Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial (SUPPORT), using a factorial design that randomized extremely preterm infants to lower vs higher oxygen saturation targets and delivery room continuous positive airway pressure (CPAP) vs intubation/surfactant. STUDY DESIGN The Breathing Outcomes Study, a prospective secondary study to the Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial, assessed respiratory morbidity at 6-month intervals from hospital discharge to 18-22 months corrected age (CA). Two prespecified primary outcomes-wheezing more than twice per week during the worst 2-week period and cough longer than 3 days without a cold-were compared for each randomized intervention. RESULTS One or more interviews were completed for 918 of the 922 eligible infants. The incidences of wheezing and cough were 47.9% and 31.0%, respectively, and did not differ between the study arms of either randomized intervention. Infants randomized to lower vs higher oxygen saturation targets had a similar risk of death or respiratory morbidity (except for croup and treatment with oxygen or diuretics at home). Infants randomized to CPAP vs intubation/surfactant had fewer episodes of wheezing without a cold (28.9% vs 36.5%; P<.05), respiratory illnesses diagnosed by a doctor (47.7% vs 55.2%; P<.05), and physician or emergency room visits for breathing problems (68.0% vs 72.9%; P<.05) by 18-22 months CA. CONCLUSION Treatment with early CPAP rather than intubation/surfactant is associated with less respiratory morbidity by 18-22 months CA. Longitudinal assessment of pulmonary morbidity is necessary to fully evaluate the potential benefits of respiratory interventions for neonates.

Influence of clinical status on the association between plasma total and unbound bilirubin and death or adverse neurodevelopmental outcomes in extremely low birth weight infants

Objectives:  To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants.

Two-hit model of brain damage in the very preterm newborn: small for gestational age and postnatal systemic inflammation

Background:We sought to disentangle the contributions of perinatal systemic inflammation and being small for gestational age (SGA) to the occurrence of low Bayley Mental Development Indices (MDIs) at the age of 2 y.Methods:We measured the concentration of 25 inflammation-related proteins in blood obtained during the first two postnatal weeks from 805 infants who were born before the 28th wk of gestation and who had MDI measurements at the age of 2 y and were able to walk independently.Results:SGA newborns who did not have systemic inflammation (a concentration of an inflammation-related protein in the top quartile for gestational age on two days a week apart) were at a greater risk of an MDI <55, but not 55–69, than their peers who had neither SGA nor systemic inflammation. SGA infants who had elevated blood concentrations of interleukin (IL)-1β, tumor necrosis factor-α, or IL-8 during the first 2 postnatal weeks were at even higher risk of an MDI <55 than their SGA peers without systemic inflammation and their non-SGA peers with systemic inflammation.Conclusion:SGA appears to place very preterm newborns at an increased risk of a very low MDI. Systemic inflammation adds considerably to the increased risk.

Cytokines and Neurodevelopmental Outcomes in Extremely Low Birth Weight Infants

OBJECTIVE To determine if selected pro-inflammatory and anti-inflammatory cytokines and/or mediators of inflammation reported to be related to the development of cerebral palsy (CP) predict neurodevelopmental outcome in extremely low birth weight infants. STUDY DESIGN Infants with birth weights ≤1000 g (n = 1067) had blood samples collected at birth and on days 3 ± 1, 7 ± 1, 14 ± 3, and 21 ± 3 to examine the association between cytokines and neurodevelopmental outcomes. The analyses were focused on 5 cytokines (interleukin [IL] 1β; IL-8; tumor necrosis factor-α; regulated upon activation, normal T-cell expressed, and secreted (RANTES); and IL-2) reported to be most predictive of CP in term and late preterm infants. RESULTS IL-8 was higher on days 0-4 and subsequently in infants who developed CP compared with infants who did not develop CP in both unadjusted and adjusted analyses. Other cytokines (IL-12, IL-17, tumor necrosis factor-β, soluble IL rα, macrophage inflammatory protein 1β) were found to be altered on days 0-4 in infants who developed CP. CONCLUSIONS CP in former preterm infants may, in part, have a late perinatal and/or early neonatal inflammatory origin.

Systemic Inflammation and Cerebral Palsy Risk in Extremely Preterm Infants

The authors hypothesized that among extremely preterm infants, elevated concentrations of inflammation-related proteins in neonatal blood are associated with cerebral palsy at 24 months. In 939 infants born before 28 weeks gestation, the authors measured blood concentrations of 25 proteins on postnatal days 1, 7, and 14 and evaluated associations between elevated protein concentrations and cerebral palsy diagnosis. Protein elevations within 3 days of birth were not associated with cerebral palsy. Elevations of tumor necrosis factor-α, tumor necrosis factor-α-receptor-1, interleukin-8, and intercellular adhesion molecule-1 on at least 2 days were associated with diparesis. Recurrent-persistent elevations of interleukin-6, E-selectin, or insulin-like growth factor binding protein-1 were associated with hemiparesis. Diparesis and hemiparesis were more likely among infants who had at least 4 of 9 protein elevations that previously have been associated with cognitive impairment and microcephaly. Repeated elevations of inflammation-related proteins during the first 2 postnatal weeks are associated with increased risk of cerebral palsy.