Serum ferritin values in neonates <29 weeks' gestation are highly variable and do not correlate with reticulocyte hemoglobin content.

OBJECTIVES: To compare serum ferritin and RET-He values among extremely low gestational age neonates ELGANs with other markers of iron-deficient erythropoiesis. STUDY DESIGN: This is a secondary analysis of the NICHD Darbepoetin Trial. Study data from placebo recipients who had a serum ferritin, a RET-He, and a mean corpuscular volume (MCV) measurement within a 24-hour period were analyzed for correlation. RESULTS: Mixed linear regression models showed no association between ferritin and RET-He at both early (ß = 0.0016, p = 0.40) and late (ß = -0.0001, p = 0.96) time points. Positive associations were observed between RET-He and MCV at baseline, early, and late time points (p < 0.01, =0.01, <0.001, respectively), while ferritin was not associated with MCV at any time point. CONCLUSIONS: Our study shows that RET-He is better correlated with MCV as a marker of iron-limited erythropoiesis than ferritin. The results suggest that ferritin is limited as a marker of iron sufficiency in premature infants. STUDY IDENTIFICATION: FDA IND Number 100138; ClinicalTrials.gov number NCT03169881; NRN ID number NICHD-NRN-0058 (Darbe).

Status and Influencing Factors of Parenteral Nutrition Practice for Late Preterm Infants in China.

Objectives: To explore the status of parental nutrition practice of hospitalized late preterm infants and the factors influencing the clinical prescription. Methods: A multi-center, prospective cohort study was conducted during October 2015 to October 2017. Infants born after 34 weeks and before 37 weeks were enrolled from twenty-five hospitals in the Beijing area of China. Data of enteral and parenteral nutrition were collected. Results: A total of 1,463 late preterm infants were enrolled in this study, 53.9% of infants were supported by parenteral nutrition. Over 60% of 34 weeks' infants were on parenteral nutrition during the 2nd to the 4th day. Logistic regression analysis showed that gestational age(GA) (OR = 0.69, 95%CI 0.58-0.81), birth weight (OR = 0.41, 95%CI 0.26-0.65), hypoglycemia (OR = 2.77, 95%CI 1.90-4.04), small for gestational age (SGA) (OR = 2.18, 95%CI 1.34-3.55), feeding intolerance (OR = 6.41, 95%CI 1.90-21.59), neonatal respiratory distress syndrome (NRDS) (OR = 2.16, 95%CI 1.12-4.18), neonatal infection(OR = 1.56 95%CI 1.16-2.10), and slow enteral nutrition advancement rate (OR = 0.92, 95%CI 0.90-0.95) were factors influencing the administration of parenteral nutrition. Conclusion: Over half of hospitalized late preterm infants were prescribed with parenteral nutrition. Infants with lower GA, lower birth weight, diagnosed with hypoglycemia, SGA, feeding intolerance, NRDS, neonatal infection, or a slower rate of enteral nutrition advancement had a higher likelihood of receiving parenteral nutrition.

Association Between Increased Seizures During Rewarming After Hypothermia for Neonatal Hypoxic Ischemic Encephalopathy and Abnormal Neurodevelopmental Outcomes at 2-Year Follow-up: A Nested Multisite Cohort Study.

Importance: Compared with normothermia, hypothermia has been shown to reduce death or disability in neonatal hypoxic ischemic encephalopathy but data on seizures during rewarming and associated outcomes are scarce. Objective: To determine whether electrographic seizures are more likely to occur during rewarming compared with the preceding period and whether they are associated with abnormal outcomes in asphyxiated neonates receiving hypothermia therapy. Design, Setting, and Participants: This prespecified nested cohort study of infants enrolled in the Optimizing Cooling (OC) multicenter Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network trial from December 2011 to December 2013 with 2 years' follow-up randomized infants to either 72 hours of cooling (group A) or 120 hours (group B). The main trial included 364 infants. Of these, 194 were screened, 10 declined consent, and 120 met all predefined inclusion criteria. A total of 112 (90%) had complete data for death or disability. Data were analyzed from January 2018 to January 2020. Interventions: Serial amplitude electroencephalography recordings were compared in the 12 hours prior and 12 hours during rewarming for evidence of electrographic seizure activity by 2 central amplitude-integrated electroencephalography readers blinded to treatment arm and rewarming epoch. Odds ratios and 95% CIs were evaluated following adjustment for center, prior seizures, depth of cooling, and encephalopathy severity. Main Outcomes and Measures: The primary outcome was the occurrence of electrographic seizures during rewarming initiated at 72 or 120 hours compared with the preceding 12-hour epoch. Secondary outcomes included death or moderate or severe disability at age 18 to 22 months. The hypothesis was that seizures during rewarming were associated with higher odds of abnormal neurodevelopmental outcomes. Results: A total of 120 newborns (70 male [58%]) were enrolled (66 in group A and 54 in group B). The mean (SD) gestational age was 39 (1) weeks. There was excellent interrater agreement (κ, 0.99) in detection of seizures. More infants had electrographic seizures during the rewarming epoch compared with the preceding epoch (group A, 27% vs 14%; P = .001; group B, 21% vs 10%; P = .03). Adjusted odd ratios (95% CIs) for seizure frequency during rewarming were 2.7 (1.0-7.5) for group A and 3.2 (0.9-11.6) for group B. The composite death or moderate to severe disability outcome at 2 years was significantly higher in infants with electrographic seizures during rewarming (relative risk [95% CI], 1.7 [1.25-2.37]) after adjusting for baseline clinical encephalopathy and seizures as well as center. Conclusions and Relevance: Findings that higher odds of electrographic seizures during rewarming are associated with death or disability at 2 years highlight the necessity of electroencephalography monitoring during rewarming in infants at risk. Trial Registration: ClinicalTrials.gov Identifier: NCT01192776.

Morbidity and cost burden of prenatal myelomeningocele repair.

OBJECTIVE: This study compared the morbidities and financial burden associated with prenatal open myelomeningocele repair versus postnatal repair. MATERIALS AND METHODS: The retrospective study cohort included 23 mother-infant dyads undergoing prenatal repair and 30 with postnatal repair. Financial, demographic, and medical information were obtained for mother-infant dyads from each infant's birth through the first year of life. RESULTS: Infants in the prenatal repair group were significantly affected by sequelae of prematurity, including apnea, bronchopulmonary dysplasia, and retinopathy of prematurity. Importantly, fewer of these infants required ventriculoperitoneal shunt procedures and the overall improved composite outcome of shunting or death. Infants in the postnatal repair group required more hospital readmissions in the first year of life. Financial costs for mother-infant dyads in the prenatal repair group were higher, driven by the length of stay in the neonatal intensive care unit and maternal hospital admissions. Kaplan-Meier curves analyzing the relative contributions of the length of stay and total charges in the population were constructed. The maternal contribution was markedly different between groups due to postoperative hospitalization, readmission, and close fetal surveillance required. Though these differences did not reach statistical significance, it highlights an important burden on families and the medical system. CONCLUSIONS: This is the first study to report the contributions of prematurity in relation to maternal and infant morbidity and financial costs. The benefits of prenatal myelomeningocele repair include lower risk for ventriculoperitoneal shunting and fewer hospital readmissions. The risk of preterm birth and its neonatal sequelae continue to be a significant burden.

Higher or Lower Hemoglobin Transfusion Thresholds for Preterm Infants.

BACKGROUND: Limited data suggest that higher hemoglobin thresholds for red-cell transfusions may reduce the risk of cognitive delay among extremely-low-birth-weight infants with anemia. METHODS: We performed an open, multicenter trial in which infants with a birth weight of 1000 g or less and a gestational age between 22 weeks 0 days and 28 weeks 6 days were randomly assigned within 48 hours after delivery to receive red-cell transfusions at higher or lower hemoglobin thresholds until 36 weeks of postmenstrual age or discharge, whichever occurred first. The primary outcome was a composite of death or neurodevelopmental impairment (cognitive delay, cerebral palsy, or hearing or vision loss) at 22 to 26 months of age, corrected for prematurity. RESULTS: A total of 1824 infants (mean birth weight, 756 g; mean gestational age, 25.9 weeks) underwent randomization. There was a between-group difference of 1.9 g per deciliter (19 g per liter) in the pretransfusion mean hemoglobin levels throughout the treatment period. Primary outcome data were available for 1692 infants (92.8%). Of 845 infants in the higher-threshold group, 423 (50.1%) died or survived with neurodevelopmental impairment, as compared with 422 of 847 infants (49.8%) in the lower-threshold group (relative risk adjusted for birth-weight stratum and center, 1.00; 95% confidence interval [CI], 0.92 to 1.10; P = 0.93). At 2 years, the higher- and lower-threshold groups had similar incidences of death (16.2% and 15.0%, respectively) and neurodevelopmental impairment (39.6% and 40.3%, respectively). At discharge from the hospital, the incidences of survival without severe complications were 28.5% and 30.9%, respectively. Serious adverse events occurred in 22.7% and 21.7%, respectively. CONCLUSIONS: In extremely-low-birth-weight infants, a higher hemoglobin threshold for red-cell transfusion did not improve survival without neurodevelopmental impairment at 22 to 26 months of age, corrected for prematurity. (Funded by the National Heart, Lung, and Blood Institute and others; TOP ClinicalTrials.gov number, NCT01702805.).

Individualized Human Milk Fortification to Improve the Growth of Hospitalized Preterm Infants.

BACKGROUND: Human milk (HM) is the first choice for preterm infants, but exclusive HM feeding is inadequate for the growth of very preterm infants. The hypothesis of this trial is that infants fed according to an individualized fortification regimen will have higher protein intake and improved weight gain velocity (WGV). METHODS: A prospective, randomized, controlled study was conducted. Infants <34 weeks of gestational age were enrolled when enteral feeding volume reached 60 mL/kg/d and were randomly allocated to the individualized fortification (IF) group or the standard fortification group. The IF group was fed using a regimen that featured modifying HM fortifier and supplemental protein powder based on the protein concentration in HM, current body weight of infants, and blood urea nitrogen (fortification level was set as L-1, L0, L1, L2, L3; the amount of HM fortifier and protein powder were determined accordingly). RESULTS: Between September 2012 and August 2016, 51 preterm infants completed the study. In the IF group, 62.5% (15/24) of preterm infants were fed with HM fortified to level 1, 29.2% (7/24) to level 2, and 12.5% (3/24) to level 3. The WGV of the third week in the IF group was greater than the standard group (20.8 ± 7.9 vs 14.9 ± 4.5 g/kg/d, P = 0.022). CONCLUSION: About two-thirds of preterm infants needed to adjust the HM fortification to a higher level. The WGV of infants in the IF group was better than that of the standard group in the third week of this study.

Achieved oxygen saturations and retinopathy of prematurity in extreme preterms.

OBJECTIVE: To identify achieved oxygen saturations (SpO2) associated with increased risk of severe retinopathy of prematurity (ROP). DESIGN: This is a secondary analysis of the Surfactant Positive Airway Pressure and Pulse Oximetry Trial (SUPPORT)randomised controlled trial. SpO2 was recorded up to 36 weeks' postmenstrual age. Saturations through 9 postnatal weeks were explored graphically, and logistic regression models were created to predict severe ROP. SETTING: 20 centres of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. PATIENTS: 984 surviving infants of 24-27 weeks' gestational age born in 2005-2009. INTERVENTIONS: SUPPORT targeted SpO2 to a lower (85%-89%) or higher (91%-95%) range through 36 weeks' postmenstrual age or off respiratory support. MAIN OUTCOME MEASURES: Severe ROP defined as threshold ROP, ophthalmological surgery or bevacizumab treatment. RESULTS: There were statistically significant interactions between duration of oxygen supplementation and percentage of time in certain achieved saturation ranges. Specifically, for infants who spent at least 2 weeks on oxygen in postnatal weeks 1-5, a higher percentage of time at 91%-96% SpO2 was associated with increased odds of severe ROP. For infants who spent at least 3 weeks on oxygen in postnatal weeks 6-9, a higher percentage of time at 97%-100% SpO2 was associated with increased odds of severe ROP. Other significant risk factors were lower gestational age and birth weight, non-Hispanic white versus black race, prospectively defined severe illness, late-onset sepsis or meningitis, and clinical centre. CONCLUSIONS: Among extremely preterm survivors to discharge, the association between SpO2 and severe ROP depended on the timing and duration of oxygen supplementation.

Effects of Myo-inositol on Type 1 Retinopathy of Prematurity Among Preterm Infants <28 Weeks' Gestational Age: A Randomized Clinical Trial.

Importance: Previous studies of myo-inositol in preterm infants with respiratory distress found reduced severity of retinopathy of prematurity (ROP) and less frequent ROP, death, and intraventricular hemorrhage. However, no large trials have tested its efficacy or safety. Objective: To test the adverse events and efficacy of myo-inositol to reduce type 1 ROP among infants younger than 28 weeks' gestational age. Design, Setting, and Participants: Randomized clinical trial included 638 infants younger than 28 weeks' gestational age enrolled from 18 neonatal intensive care centers throughout the United States from April 17, 2014, to September 4, 2015; final date of follow-up was February 12, 2016. The planned enrollment of 1760 participants would permit detection of an absolute reduction in death or type 1 ROP of 7% with 90% power. The trial was terminated early due to a statistically significantly higher mortality rate in the myo-inositol group. Interventions: A 40-mg/kg dose of myo-inositol was given every 12 hours (initially intravenously, then enterally when feeding; n = 317) or placebo (n = 321) for up to 10 weeks. Main Outcomes and Measures: Type 1 ROP or death before determination of ROP outcome was designated as unfavorable. The designated favorable outcome was survival without type 1 ROP. Results: Among 638 infants (mean, 26 weeks' gestational age; 50% male), 632 (99%) received the trial drug or placebo and 589 (92%) had a study outcome. Death or type 1 ROP occurred more often in the myo-inositol group vs the placebo group (29% vs 21%, respectively; adjusted risk difference, 7% [95% CI, 0%-13%]; adjusted relative risk, 1.41 [95% CI, 1.08-1.83], P = .01). All-cause death before 55 weeks' postmenstrual age occurred in 18% of the myo-inositol group and in 11% of the placebo group (adjusted risk difference, 6% [95% CI, 0%-11%]; adjusted relative risk, 1.66 [95% CI, 1.14-2.43], P = .007). The most common serious adverse events up to 7 days of receiving the ending dose were necrotizing enterocolitis (6% for myo-inositol vs 4% for placebo), poor perfusion or hypotension (7% vs 4%, respectively), intraventricular hemorrhage (10% vs 9%), systemic infection (16% vs 11%), and respiratory distress (15% vs 13%). Conclusions and Relevance: Among premature infants younger than 28 weeks' gestational age, treatment with myo-inositol for up to 10 weeks did not reduce the risk of type 1 ROP or death vs placebo. These findings do not support the use of myo-inositol among premature infants; however, the early termination of the trial limits definitive conclusions.

Multi-center Study of Enteral Feeding Practices in Hospitalized Late Preterm Infants in China.

OBJECTIVE: To investigate the current enteral feeding practices in hospitalized late preterm infants in the Beijing area of China. METHODS: A multi-center, cross-sectional study was conducted. Infants born after 34 weeks and before 37 weeks of gestation were enrolled from 25 hospitals in the Beijing area of China from October 2015 to October 2017. Data on enteral feeding practices were collected and analyzed. RESULTS: A total of 1,463 late preterm infants were enrolled, with a mean gestational age (GA) of 35.6 (34.9, 36.1) weeks. The percentage of exclusive breastfeeding was 4.5% at the initiation of enteral feeding but increased to 14.4% at discharge. When human milk was not available, most infants (46.1%) were fed with preterm infant formula. The rate of exclusive human milk feeding in infants born at 34 weeks gestation was higher than at discharge (21.1% of infants born at 34 weeks' GA versus 12.1% of infants born at 35 weeks' GA versus 12.3% of infants born at 36 weeks' GA, P < 0.001). Only 28.4% of late preterm infants achieved full enteral feeding at discharge, and only 19.2% achieved 120 kcal/(kg•d) by enteral feeding at discharge. Importantly, 40.5% of infants did not regain the birth weight at discharge. CONCLUSION: Enteral feeding support of late preterm infants has not been standardized to achieve optimal growth. Moreover, the human milk feeding rate was low, and many late preterm infants did not achieve the goal of enteral feeding and failed to regain birth weight at the time of discharge. More aggressive enteral feedings protocols are needed to promote human milk feeding and optimize growth for late preterm infants.

A quality improvement initiative to reduce necrotizing enterocolitis across hospital systems.

OBJECTIVE: Necrotizing enterocolitis (NEC) is a devastating intestinal disease in premature infants. Local rates of NEC were unacceptably high. We hypothesized that utilizing quality improvement methodology to standardize care and apply evidence-based practices would reduce our rate of NEC. STUDY DESIGN: A multidisciplinary team used the model for improvement to prioritize interventions. Three neonatal intensive care units (NICUs) developed a standardized feeding protocol for very low birth weight (VLBW) infants, and employed strategies to increase the use of human milk, maximize intestinal perfusion, and promote a healthy microbiome. RESULTS: The primary outcome measure, NEC in VLBW infants, decreased from 0.17 cases/100 VLBW patient days to 0.029, an 83% reduction, while the compliance with a standardized feeding protocol improved. CONCLUSION: Through reliable implementation of evidence-based practices, this project reduced the regional rate of NEC by 83%. A key outcome and primary driver of success was standardization across multiple NICUs, resulting in consistent application of best practices and reduction in variation.

The Impact of Maternal Antibiotics on Neonatal Disease.

OBJECTIVES: We examined the impact of prenatal exposure to maternal antibiotics on risk of necrotizing enterocolitis (NEC), late onset sepsis (LOS), and death in infants born preterm. STUDY DESIGN: Secondary data analysis was conducted via an extant cohort of 580 infants born <32 weeks of gestation and enrolled in 3 level III neonatal intensive care units. Prenatal antibiotic exposure was defined as antibiotics received by the mother within 72 hours before delivery. Postnatal empiric antibiotic exposure was defined as antibiotic initiated within the first day of life without documented infection, categorized as low (<5 days) or high (>5 days) duration. RESULTS: Two-thirds of mothers received antibiotics within 72 hours before delivery, of whom 59.8% received >1 antibiotic. Ampicillin (37.6%) and azithromycin (26.4%) were the most common antibiotics given. NEC occurred in 7.5%, LOS in 11.1%, death in 9.6%, and the combined outcome of NEC, LOS, or death in 21.3% of study infants. In multiple logistic regression models adjusted for gestational age, postnatal empiric antibiotic exposure, and other factors, prenatal antibiotic exposure was associated with reduced risk of NEC (OR 0.28; 95% CI 0.14-0.56; P < .001), death (OR 0.29; 95% CI 0.14-0.60; P = .001), but not LOS (OR 1.59; 95% CI 0.84-2.99; P = .15), although protection was significant for the combined outcome (OR 0.52, P < .001). High postnatal empiric antibiotic exposure was associated with greater risk of death but not other outcomes in multiple regression models (OR 3.18, P = .002). CONCLUSIONS: Prenatal antibiotic exposure was associated with lower rates of NEC or death of infants born preterm, and its impact on infant outcomes warrants further study.

Surgical necrotizing enterocolitis in extremely premature neonates is associated with genetic variations in an intergenic region of chromosome 8.

BackgroundTwin studies suggest that genetic factors may account for up to 50% increased risk for necrotizing enterocolitis (NEC), but genome-wide association studies for NEC are lacking.MethodsGenotyping was done on Illumina BeadChip, followed by analysis using PLINK with logistic regression under an additive model.ResultsAmong 751 extremely-low-birth-weight (<1,000 g, >401 g) neonates, 30 had surgical NEC. Two hundred and sixty-one single-nucleotide polymorphisms (SNPs) showed association with NEC at P<0.05, of which 35 were significant at P<10-7. Minor allele(s) in a cluster of SNPs spanning a 43-kb region of chromosome 8 (8q23.3) conferred an odds ratio of 4.72 (95% confidence interval (CI): 2.51-8.88) for elevated risk of NEC. Two smaller clusters on chromosome 14 and chromosome 11 exhibited P values of 10-7-10-8. The chromosome 8 cluster is in an intergenic region between CUB and Sushi multiple domains 3 (-1.43 Mb) and trichorhinophalangeal syndrome I (+542 kb). RNA sequencing in this region identified a potential novel open-reading frame corresponding to a long interspersed element-1 retrotransposable element.ConclusionGenetic variation in an intergenic region of chromosome 8 is associated with increased risk for NEC with a mechanism that is yet to be identified.

Effect of Depth and Duration of Cooling on Death or Disability at Age 18 Months Among Neonates With Hypoxic-Ischemic Encephalopathy: A Randomized Clinical Trial.

IMPORTANCE: Hypothermia for 72 hours at 33.5°C for neonatal hypoxic-ischemic encephalopathy reduces death or disability, but rates continue to be high. OBJECTIVE: To determine if cooling for 120 hours or to a temperature of 32.0°C reduces death or disability at age 18 months in infants with hypoxic-ischemic encephalopathy. DESIGN, SETTING, AND PARTICIPANTS: Randomized 2 × 2 factorial clinical trial in neonates (≥36 weeks' gestation) with hypoxic-ischemic encephalopathy at 18 US centers in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network between October 2010 and January 2016. INTERVENTIONS: A total of 364 neonates were randomly assigned to 4 hypothermia groups: 33.5°C for 72 hours (n = 95), 32.0°C for 72 hours (n = 90), 33.5°C for 120 hours (n = 96), or 32.0°C for 120 hours (n = 83). MAIN OUTCOMES AND MEASURES: The primary outcome was death or moderate or severe disability at 18 to 22 months of age adjusted for center and level of encephalopathy. Severe disability included any of Bayley Scales of Infant Development III cognitive score less than 70, Gross Motor Function Classification System (GMFCS) level of 3 to 5, or blindness or hearing loss despite amplification. Moderate disability was defined as a cognitive score of 70 to 84 and either GMFCS level 2, active seizures, or hearing with amplification. RESULTS: The trial was stopped for safety and futility in November 2013 after 364 of the planned 726 infants were enrolled. Among 347 infants (95%) with primary outcome data (mean age at follow-up, 20.7 [SD, 3.5] months; 42% female), death or disability occurred in 56 of 176 (31.8%) cooled for 72 hours and 54 of 171 (31.6%) cooled for 120 hours (adjusted risk ratio, 0.92 [95% CI, 0.68-1.25]; adjusted absolute risk difference, -1.0% [95% CI, -10.2% to 8.1%]) and in 59 of 185 (31.9%) cooled to 33.5°C and 51 of 162 (31.5%) cooled to 32.0°C (adjusted risk ratio, 0.92 [95% CI, 0.68-1.26]; adjusted absolute risk difference, -3.1% [95% CI, -12.3% to 6.1%]). A significant interaction between longer and deeper cooling was observed (P = .048), with primary outcome rates of 29.3% at 33.5°C for 72 hours, 34.5% at 32.0°C for 72 hours, 34.4% at 33.5°C for 120 hours, and 28.2% at 32.0°C for 120 hours. CONCLUSIONS AND RELEVANCE: Among term neonates with moderate or severe hypoxic-ischemic encephalopathy, cooling for longer than 72 hours, cooling to lower than 33.5°C, or both did not reduce death or moderate or severe disability at 18 months of age. However, the trial may be underpowered, and an interaction was found between longer and deeper cooling. These results support the current regimen of cooling for 72 hours at 33.5°C. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01192776.

Neonatal outcomes of moderately preterm infants compared to extremely preterm infants.

BackgroundExtremely preterm infants (EPT, <29 weeks' gestation) represent only 0.9% of births in the United States; yet these infants are the focus of most published research. Moderately preterm neonates (MPT, 29-336/7 weeks) are an understudied group of high-risk infants.MethodsTo determine the neonatal outcomes of MPT infants across the gestational age spectrum, and to compare these with EPT infants. A prospective observational cohort was formed in 18 level 3-4 neonatal intensive care units (NICUs) in the Eunice Kennedy Shriver NICHD Neonatal Research Network. Participants included all MPT infants admitted to NICUs and all EPT infants born at sites between January 2012 and November 2013. Antenatal characteristics and neonatal morbidities were abstracted from records using pre-specified definitions by trained neonatal research nurses.ResultsMPT infants experienced morbidities similar to, although at lower rates than, those of EPT infants. The main cause of mortality was congenital malformation, accounting for 43% of deaths. Central Nervous System injury occurred, including intraventricular hemorrhage. Most MPT infants required respiratory support, but sequelae such as bronchopulmonary dysplasia were rare. The primary contributors to hospitalization beyond 36 weeks' gestation were inability to achieve adequate oral intake and persistent apnea.ConclusionsMPT infants experience morbidity and prolonged hospitalization. Such morbidity deserves focused research to improve therapeutic and prevention strategies.

Antenatal Determinants of Bronchopulmonary Dysplasia and Late Respiratory Disease in Preterm Infants.

RATIONALE: Mechanisms contributing to chronic lung disease after preterm birth are incompletely understood. OBJECTIVES: To identify antenatal risk factors associated with increased risk for bronchopulmonary dysplasia (BPD) and respiratory disease during early childhood after preterm birth, we performed a prospective, longitudinal study of 587 preterm infants with gestational age less than 34 weeks and birth weights between 500 and 1,250 g. METHODS: Data collected included perinatal information and assessments during the neonatal intensive care unit admission and longitudinal follow-up by questionnaire until 2 years of age. MEASUREMENTS AND MAIN RESULTS: After adjusting for covariates, we found that maternal smoking prior to preterm birth increased the odds of having an infant with BPD by twofold (P = 0.02). Maternal smoking was associated with prolonged mechanical ventilation and respiratory support during the neonatal intensive care unit admission. Preexisting hypertension was associated with a twofold (P = 0.04) increase in odds for BPD. Lower gestational age and birth weight z-scores were associated with BPD. Preterm infants who were exposed to maternal smoking had higher rates of late respiratory disease during childhood. Twenty-two percent of infants diagnosed with BPD and 34% of preterm infants without BPD had no clinical signs of late respiratory disease during early childhood. CONCLUSIONS: We conclude that maternal smoking and hypertension increase the odds for developing BPD after preterm birth, and that maternal smoking is strongly associated with increased odds for late respiratory morbidities during early childhood. These findings suggest that in addition to the BPD diagnosis at 36 weeks, other factors modulate late respiratory outcomes during childhood. We speculate that measures to reduce maternal smoking not only will lower the risk for preterm birth but also will improve late respiratory morbidities after preterm birth.

Genome-wide association study of sepsis in extremely premature infants.

OBJECTIVE: To identify genetic variants associated with sepsis (early-onset and late-onset) using a genome-wide association (GWA) analysis in a cohort of extremely premature infants. STUDY DESIGN: Previously generated GWA data from the Neonatal Research Network's anonymised genomic database biorepository of extremely premature infants were used for this study. Sepsis was defined as culture-positive early-onset or late-onset sepsis or culture-proven meningitis. Genomic and whole-genome-amplified DNA was genotyped for 1.2 million single-nucleotide polymorphisms (SNPs); 91% of SNPs were successfully genotyped. We imputed 7.2 million additional SNPs. p Values and false discovery rates (FDRs) were calculated from multivariate logistic regression analysis adjusting for gender, gestational age and ancestry. Target statistical value was p<10-5. Secondary analyses assessed associations of SNPs with pathogen type. Pathway analyses were also run on primary and secondary end points. RESULTS: Data from 757 extremely premature infants were included: 351 infants with sepsis and 406 infants without sepsis. No SNPs reached genome-wide significance levels (5×10-8); two SNPs in proximity to FOXC2 and FOXL1 genes achieved target levels of significance. In secondary analyses, SNPs for ELMO1, IRAK2 (Gram-positive sepsis), RALA, IMMP2L (Gram-negative sepsis) and PIEZO2 (fungal sepsis) met target significance levels. Pathways associated with sepsis and Gram-negative sepsis included gap junctions, fibroblast growth factor receptors, regulators of cell division and interleukin-1-associated receptor kinase 2 (p values<0.001 and FDR<20%). CONCLUSIONS: No SNPs met genome-wide significance in this cohort of extremely low birthweight infants; however, areas of potential association and pathways meriting further study were identified.

Association of Chorioamnionitis with Aberrant Neonatal Gut Colonization and Adverse Clinical Outcomes.

OBJECTIVE: Chorioamnionitis (inflammation of the placenta and fetal membranes) and abnormal gastrointestinal colonization have been associated with an increased risk of sepsis and death in preterm infants, but whether chorioamnionitis causes abnormal pioneering gastrointestinal colonization in infants is not known. We determined the relationship between chorioamnionitis, altered infant fecal microbiome indicating abnormal gastrointestinal colonization, and adverse outcomes. STUDY DESIGN: Preterm infants ≤ 28 weeks at birth were enrolled from 3 level III NICUs in Cincinnati, Ohio and Birmingham, Alabama. Sequencing for 16S microbial gene was performed on stool samples in the first 3 weeks of life. Chorioamnionitis was diagnosed by placental histology. Late onset sepsis and death outcomes were analyzed in relation to fecal microbiota and chorioamnionitis with or without funisitis (inflammation of the umbilical cord). RESULTS: Of the 106 enrolled infants, 48 infants had no chorioamnionitis, 32 infants had chorioamnionitis but no funisitis (AC), and 26 infants had chorioamnionitis with funisitis (ACF). The fecal samples from ACF infants collected by day of life 7 had higher relative abundance of family Mycoplasmataceae (phylum Tenericutes), genus Prevotella (phylum Bacteroidetes) and genus Sneathia (phylum Fusobacteria). Further, AC and ACF infants had higher incidence of late-onset sepsis/death as a combined outcome. Presence of specific clades in fecal samples, specifically, order Fusobacteria, genus Sneathia or family Mycoplasmataceae, were significantly associated with higher risk of sepsis or death. CONCLUSION: The results support the hypothesis that specific alterations in the pioneering infant gastrointestinal microbiota induced by chorioamnionitis predispose to neonatal sepsis or death.

Growth Outcomes of Preterm Infants Exposed to Different Oxygen Saturation Target Ranges from Birth.

OBJECTIVE: To test whether infants randomized to a lower oxygen saturation (peripheral capillary oxygen saturation [SpO2]) target range while on supplemental oxygen from birth will have better growth velocity from birth to 36 weeks postmenstrual age (PMA) and less growth failure at 36 weeks PMA and 18-22 months corrected age. STUDY DESIGN: We evaluated a subgroup of 810 preterm infants from the Surfactant, Positive Pressure, and Oxygenation Randomized Trial, randomized at birth to lower (85%-89%, n = 402, PMA 26 ± 1 weeks, birth weight 839 ± 186 g) or higher (91%-95%, n = 408, PMA 26 ± 1 weeks, birth weight 840 ± 191 g) SpO2 target ranges. Anthropometric measures were obtained at birth, postnatal days 7, 14, 21, and 28; then at 32 and 36 weeks PMA; and 18-22 months corrected age. Growth velocities were estimated with the exponential method and analyzed with linear mixed models. Poor growth outcome, defined as weight <10th percentile at 36 weeks PMA and 18-22 months corrected age, was compared across the 2 treatment groups by the use of robust Poisson regression. RESULTS: Growth outcomes including growth at 36 weeks PMA and 18-22 months corrected age, as well as growth velocity were similar in the lower and higher SpO2 target groups. CONCLUSION: Targeting different oxygen saturation ranges between 85% and 95% from birth did not impact growth velocity or reduce growth failure in preterm infants.

Metagenomic Sequencing with Strain-Level Resolution Implicates Uropathogenic E. coli in Necrotizing Enterocolitis and Mortality in Preterm Infants.

Necrotizing enterocolitis (NEC) afflicts approximately 10% of extremely preterm infants with high fatality. Inappropriate bacterial colonization with Enterobacteriaceae is implicated, but no specific pathogen has been identified. We identify uropathogenic E. coli (UPEC) colonization as a significant risk factor for the development of NEC and subsequent mortality. We describe a large-scale deep shotgun metagenomic sequence analysis of the early intestinal microbiome of 144 preterm and 22 term infants. Using a pan-genomic approach to functionally subtype the E. coli, we identify genes associated with NEC and mortality that indicate colonization by UPEC. Metagenomic multilocus sequence typing analysis further defined NEC-associated strains as sequence types often associated with urinary tract infections, including ST69, ST73, ST95, ST127, ST131, and ST144. Although other factors associated with prematurity may also contribute, this report suggests a link between UPEC and NEC and indicates that further attention to these sequence types as potential causal agents is needed.

Trends in Care Practices, Morbidity, and Mortality of Extremely Preterm Neonates, 1993-2012.

IMPORTANCE: Extremely preterm infants contribute disproportionately to neonatal morbidity and mortality. OBJECTIVE: To review 20-year trends in maternal/neonatal care, complications, and mortality among extremely preterm infants born at Neonatal Research Network centers. DESIGN, SETTING, PARTICIPANTS: Prospective registry of 34,636 infants, 22 to 28 weeks' gestation, birth weight of 401 to 1500 g, and born at 26 network centers between 1993 and 2012. EXPOSURES: Extremely preterm birth. MAIN OUTCOMES AND MEASURES: Maternal/neonatal care, morbidities, and survival. Major morbidities, reported for infants who survived more than 12 hours, were severe necrotizing enterocolitis, infection, bronchopulmonary dysplasia, severe intracranial hemorrhage, cystic periventricular leukomalacia, and/or severe retinopathy of prematurity. Regression models assessed yearly changes and were adjusted for study center, race/ethnicity, gestational age, birth weight for gestational age, and sex. RESULTS: Use of antenatal corticosteroids increased from 1993 to 2012 (24% [348 of 1431 infants]) to 87% (1674 of 1919 infants]; P < .001), as did cesarean delivery (44% [625 of 1431 births] to 64% [1227 of 1921]; P < .001). Delivery room intubation decreased from 80% (1144 of 1433 infants) in 1993 to 65% (1253 of 1922) in 2012 (P < .001). After increasing in the 1990s, postnatal steroid use declined to 8% (141 of 1757 infants) in 2004 (P < .001), with no significant change thereafter. Although most infants were ventilated, continuous positive airway pressure without ventilation increased from 7% (120 of 1666 infants) in 2002 to 11% (190 of 1756 infants) in 2012 (P < .001). Despite no improvement from 1993 to 2004, rates of late-onset sepsis declined between 2005 and 2012 for infants of each gestational age (median, 26 weeks [37% {109 of 296} to 27% {85 of 320}]; adjusted relative risk [RR], 0.93 [95% CI, 0.92-0.94]). Rates of other morbidities declined, but bronchopulmonary dysplasia increased between 2009 and 2012 for infants at 26 to 27 weeks' gestation (26 weeks, 50% [130 of 258] to 55% [164 of 297]; P < .001). Survival increased between 2009 and 2012 for infants at 23 weeks' gestation (27% [41 of 152] to 33% [50 of 150]; adjusted RR, 1.09 [95% CI, 1.05-1.14]) and 24 weeks (63% [156 of 248] to 65% [174 of 269]; adjusted RR, 1.05 [95% CI, 1.03-1.07]), with smaller relative increases for infants at 25 and 27 weeks' gestation, and no change for infants at 22, 26, and 28 weeks' gestation. Survival without major morbidity increased approximately 2% per year for infants at 25 to 28 weeks' gestation, with no change for infants at 22 to 24 weeks' gestation. CONCLUSIONS AND RELEVANCE: Among extremely preterm infants born at US academic centers over the last 20 years, changes in maternal and infant care practices and modest reductions in several morbidities were observed, although bronchopulmonary dysplasia increased. Survival increased most markedly for infants born at 23 and 24 weeks' gestation and survival without major morbidity increased for infants aged 25 to 28 weeks. These findings may be valuable in counseling families and developing novel interventions. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00063063.