Detailed statistical analysis plan for ALBINO: effect of Allopurinol in addition to hypothermia for hypoxic-ischemic Brain Injury on Neurocognitive Outcome - a blinded randomized placebo-controlled parallel group multicenter trial for superiority (phase III).

BACKGROUND: Despite therapeutic hypothermia (TH) and neonatal intensive care, 45-50% of children affected by moderate-to-severe neonatal hypoxic-ischemic encephalopathy (HIE) die or suffer from long-term neurodevelopmental impairment. Additional neuroprotective therapies are sought, besides TH, to further improve the outcome of affected infants. Allopurinol - a xanthine oxidase inhibitor - reduced the production of oxygen radicals and subsequent brain damage in pre-clinical and preliminary human studies of cerebral ischemia and reperfusion, if administered before or early after the insult. This ALBINO trial aims to evaluate the efficacy and safety of allopurinol administered immediately after birth to (near-)term infants with early signs of HIE. METHODS/DESIGN: The ALBINO trial is an investigator-initiated, randomized, placebo-controlled, double-blinded, multi-national parallel group comparison for superiority investigating the effect of allopurinol in (near-)term infants with neonatal HIE. Primary endpoint is long-term outcome determined as survival with neurodevelopmental impairment versus death versus non-impaired survival at 2 years. RESULTS: The primary analysis with three mutually exclusive responses (healthy, death, composite outcome for impairment) will be on the intention-to-treat (ITT) population by a generalized logits model according to Bishop, Fienberg, Holland (Bishop YF, Discrete Multivariate Analysis: Therory and Practice, 1975) and ."will be stratified for the two treatment groups. DISCUSSION: The statistical analysis for the ALBINO study was defined in detail in the study protocol and implemented in this statistical analysis plan published prior to any data analysis. This is in accordance with the Declaration of Helsinki and the International Conference on Harmonization Good Clinical Practice guidelines. TRIAL REGISTRATION: ClinicalTrials.gov NCT03162653. Registered on 22 May 2017.

Morbidity and Mortality of Very-Low-Birthweight Twin Infants according to Their Sex and the Sex of the Co-Twin: A Retrospective Cohort Study.

INTRODUCTION: The concept of male disadvantage regarding the prognosis of premature newborns was introduced more than half a century ago, and it has been corroborated over time. However, the influence of the sex of one twin on the outcomes of the other has yielded contradictory results. OBJECTIVE: The aim of the study was to determine if, in twin pregnancies of VLBW infants, the outcomes of one twin are modified by the sex of the co-twin. METHODS: A multicentre retrospective study of a cohort of infants admitted to the collaborating units of the Spanish SEN1500 neonatal network was conducted. Liveborn VLBW twin infants, from 23+0 to 31+6 weeks of gestational age (GA), admitted from 2011 to 2020 were included. Outborn patients, infants with major congenital anomalies, and cases with only one twin admitted were excluded. The main outcomes were survival until first hospital discharge, survival without moderate or severe bronchopulmonary dysplasia (BPD), survival without major brain damage (MBD), and survival without major morbidity. Incidence rate ratios (IRR) and 95% confidence intervals (CI) were calculated. RESULTS: 2,111 twin pairs were included. Male infants exhibited worse outcomes than females (IRR; 95% CI) regarding survival (0.96; 0.94, 0.98), survival without moderate or severe BPD (0.89; 0.86, 0.93), survival without MBD (0.94; 0.91, 0.97), and survival without major morbidity (0.87; 0.81, 0.93). Differences disappeared when the co-twin was a female infant: survival (1.00; 0.97, 1.03), survival without moderate or severe BPD (0.96; 0.91, 1.01), survival without MBD (0.99; 0.95, 1.04), and survival without major morbidity (0.94; 0.85, 1.03). Results for female infants did not change significantly with co-twin sex. CONCLUSIONS: Among VLBW twins from 23+0 to 31+6 weeks of GA, male infants have higher risk of morbidity and mortality overall. In cases of pregnancies with different-sex foetuses, males seem to improve their results, while these do not change for females. The underlying mechanism of this influence deserves further investigation.

Trends, Characteristic, and Outcomes of Preterm Infants Who Received Postnatal Corticosteroid: A Cohort Study from 7 High-Income Countries.

INTRODUCTION: Our objective was to evaluate the temporal trend of systemic postnatal steroid (PNS) receipt in infants of 24-28 weeks' gestational age, identify characteristics associated with PNS receipt, and correlate PNS receipt with the incidence of bronchopulmonary dysplasia (BPD) and BPD/death from an international cohort included in the iNeo network. METHODS: We conducted a retrospective study using data from 2010 to 2018 from seven international networks participating in iNeo (Canada, Finland, Israel, Japan, Spain, Sweden, and Switzerland). Neonates of 24 and 28 weeks' gestational age who survived 7 days and who received PNS were included. We assessed temporal trend of rates of systemic PNS receipt and BPD/death. RESULTS: A total of 47,401 neonates were included. The mean (SD) gestational age was 26.4 (1.3) weeks and birth weight was 915 (238) g. The PNS receipt rate was 21% (12-28% across networks) and increased over the years (18% in 2010 to 26% in 2018; p < 0.01). The BPD rate was 39% (28-44% across networks) and remained unchanged over the years (35.2% in 2010 to 35.0% in 2018). Lower gestation, male sex, small for gestational age status, and presence of persistent ductus arteriosus (PDA) were associated with higher rates of PNS receipt, BPD, and BPD/death. CONCLUSION: The use of PNS in extremely preterm neonates increased, but there was no correlation between increased use and the BPD rate. Research is needed to determine the optimal timing, dose, and indication for PNS use in preterm neonates.

Early molecular markers of ventilator-associated pneumonia in bronchoalveolar lavage in preterm infants.

INTRODUCTION: Ventilator-associated pneumonia (VAP) constitutes a serious nosocomial infection. Our aim was to evaluate the reliability of cytokines and oxidative stress/inflammation biomarkers in bronchoalveolar lavage fluid (BALF) and tracheal aspirates (TA) as early biomarkers of VAP in preterm infants. METHODS: Two cohorts were enrolled, one to select candidates and the other for validation. In both, we included preterms with suspected VAP, according to BALF culture, they were classified into confirmed VAP and no VAP. Concentration of 16 cytokines and 8 oxidative stress/inflammation biomarkers in BALF and TA was determined in all patients. RESULTS: In the first batch, IL-17A and TNF-α in BALF, and in the second one IL-10, IL-6, and TNF-α in BALF were significantly higher in VAP patients. BALF TNF-α AUC in both cohorts was 0.86 (sensitivity 0.83, specificity 0.88). No cytokine was shown to be predictive of VAP in TA. A statistically significant increase in the VAP group was found for glutathione sulfonamide (GSA) in BALF and TA. CONCLUSIONS: TNF-α in BALF and GSA in BALF and TA were associated with VAP in preterm newborns; thus, they could be used as early biomarkers of VAP. Further studies with an increased number of patients are needed to confirm these results. IMPACT: We found that TNF-α BALF and GSA in both BALF and TA are capable of discriminating preterm infants with VAP from those with pulmonary pathology without infection. This is the first study in preterm infants aiming to evaluate the reliability of cytokines and oxidative stress/inflammation biomarkers in BALF and TA as early diagnostic markers of VAP. We have validated these results in two independent cohorts of patients. Previously studies have focused on full-term neonates and toddlers and determined biomarkers mostly in TA, but none was exclusively conducted in preterm infants.

Survival and Survival without Major Morbidity Seem to Be Consistently Better throughout Gestational Age in 24- to 30-Week Gestational Age Very-Low-Birth-Weight Female Infants Compared to Males.

INTRODUCTION: Several studies showed advantages in outcomes for very-low-birth-weight (VLBW) female infants. It has been suggested that recent advances in perinatal care might have benefited boys relatively more than girls, making differences disappear. OBJECTIVES: The aims of the study were (1) to determine if sex differences in survival and survival without morbidity in VLBW infants are still present in the context of more advanced perinatal care and (2) to know whether these differences are consistent throughout gestational age (GA). METHODS: Retrospective cohort study in seven countries participating in the Spanish SEN1500 and the South American NEOCOSUR neonatal networks. We included VLBW infants 24-30 weeks' GA, born alive without major congenital anomalies (2013-2016). Major morbidity, survival, and survival without morbidity were compared between male and female infants overall and stratified by GA. RESULTS: 10,565 patients were included: 5,620 (53.2%) males and 4,945 (46.8%) females. Female infants exhibited a lower incidence rate ratio (95% CI) of respiratory distress syndrome: 0.91 (0.88, 0.94), necrotizing enterocolitis: 0.83 (0.74, 0.93), major brain damage: 0.79 (0.72, 0.86), moderate-severe bronchopulmonary dysplasia (BPD): 0.77 (0.72, 0.83), higher survival: 1.03 (1.01, 1.05), survival without BPD: 1.11 (1.07, 1.16), survival without major brain damage: 1.05 (1.02, 1.08), and survival without major morbidity: 1.14 (1.07, 1.21). Survival and survival without morbidity were almost consistently favourable to females throughout GA. CONCLUSIONS: Our findings suggest that perinatal results continue to be favourable for VLBW female infants in the context of current perinatology, and that they are almost consistent throughout GA.

Pulmonary hypertension and oxidative stress: Where is the link?

Oxidative stress can be associated with hyperoxia and hypoxia and is characterized by an increase in reactive oxygen (ROS) and nitrogen (RNS) species generated by an underlying disease process or by supplemental oxygen that exceeds the neutralization capacity of the organ system. ROS and RNS acting as free radicals can inactive several enzymes and vasodilators in the nitric oxide pathway promoting pulmonary vasoconstriction resulting in persistent pulmonary hypertension of the newborn (PPHN). Studies in animal models of PPHN have shown high ROS/RNS that is further increased by hyperoxic ventilation. In addition, antioxidant therapy increased PaO2 in these models, but clinical trials are lacking. We recommend targeting preductal SpO2 between 90 and 97%, PaO2 between 55 and 80 mmHg and avoiding FiO2 > 0.6-0.8 if possible during PPHN management. This review highlights the role of oxidative and nitrosative stress markers on PPHN and potential therapeutic interventions that may alleviate the consequences of increased oxidant stress during ventilation with supplemental oxygen.

Nests of dividing neuroblasts sustain interneuron production for the developing human brain.

The human cortex contains inhibitory interneurons derived from the medial ganglionic eminence (MGE), a germinal zone in the embryonic ventral forebrain. How this germinal zone generates sufficient interneurons for the human brain remains unclear. We found that the human MGE (hMGE) contains nests of proliferative neuroblasts with ultrastructural and transcriptomic features that distinguish them from other progenitors in the hMGE. When dissociated hMGE cells are transplanted into the neonatal mouse brain, they reform into nests containing proliferating neuroblasts that generate young neurons that migrate extensively into the mouse forebrain and mature into different subtypes of functional interneurons. Together, these results indicate that the nest organization and sustained proliferation of neuroblasts in the hMGE provide a mechanism for the extended production of interneurons for the human forebrain.

Five-minute Apgar score and outcomes in neonates of 24-28 weeks' gestation.

OBJECTIVES: To assess associations between 5 min Apgar score and mortality and severe neurological injury (SNI) and to report test characteristics in preterm neonates. DESIGN, SETTING AND PATIENTS: Retrospective cohort study of neonates 240 to 286 weeks' gestation born between 2007 and 2016 and admitted to neonatal units in 11 high-income countries. EXPOSURE: 5 min Apgar score. MAIN OUTCOME MEASURES: In-hospital mortality and SNI defined as grade 3 or 4 periventricular/intraventricular haemorrhage or periventricular leukomalacia. Outcome rates were calculated for each Apgar score and compared after adjustment. The diagnostic characteristics and ORs for each value from 0 versus 1-10 to 0-9 versus 10, with 1-point increments were calculated. RESULTS: Among 92 412 included neonates, as 5 min Apgar score increased from 0 to 10, mortality decreased from 60% to 8%. However, no clear increasing or decreasing pattern was identified for SNI. There was an increase in sensitivity and decrease in specificity for both mortality and SNI associated with increasing scores. The Apgar score alone had an area under the curve of 0.64 for predicting mortality, which increased to 0.73 with the addition of gestational age. CONCLUSIONS: In neonates of 24-28 weeks' gestation admitted to neonatal units, higher 5 min Apgar score was associated with lower mortality in a graded manner, while the association with SNI remained relatively constant at all scores. Among survivors, low Apgar scores did not predict SNI.

Outcomes of delivery room resuscitation of bradycardic preterm infants: A retrospective cohort study of randomised trials of high vs low initial oxygen concentration and an individual patient data analysis.

OBJECTIVE: To determine whether hospital mortality (primary outcome) is associated with duration of bradycardia without chest compressions during delivery room (DR) resuscitation in a retrospective cohort study of randomized controlled trials (RCTs) in preterm infants assigned low versus high initial oxygen concentration. METHODS: Medline and EMBASE were searched from 01/01/1990 to 12/01/2020. RCTs of low vs high initial oxygen concentration which recorded serial heart rate (HR) and oxygen saturation (SpO2) during resuscitation of infants <32 weeks gestational age were eligible. Individual patient level data were requested from the authors. Newborns receiving chest compressions in the DR and those with no recorded HR in the first 2 min after birth were excluded. Prolonged bradycardia (PB) was defined as HR < 100 bpm for ≥2 min. Individual patient data analysis and pooled data analysis were conducted. RESULTS: Data were collected from 720 infants in 8 RCTs. Neonates with PB had higher odds of hospital death before [OR 3.8 (95% CI 1.5, 9.3)] and after [OR 1.7 (1.2, 2.5)] adjusting for potential confounders. Bradycardia occurred in 58% infants, while 38% had PB. Infants with bradycardia were more premature and had lower birth weights. The incidence of bradycardia in infants resuscitated with low (≤30%) and high (≥60%) oxygen was similar. Neonates with both, PB and SpO2 < 80% at 5 min after birth had higher odds of hospital mortality. [OR 18.6 (4.3, 79.7)]. CONCLUSION: In preterm infants who did not receive chest compressions in the DR, prolonged bradycardia is associated with hospital mortality.

A multi-centre randomised controlled trial of respiratory function monitoring during stabilisation of very preterm infants at birth.

AIM: To determine whether the use of a respiratory function monitor (RFM) during PPV of extremely preterm infants at birth, compared with no RFM, leads to an increase in percentage of inflations with an expiratory tidal volume (Vte) within a predefined target range. METHODS: Unmasked, randomised clinical trial conducted October 2013 - May 2019 in 7 neonatal intensive care units in 6 countries. Very preterm infants (24-27 weeks of gestation) receiving PPV at birth were randomised to have a RFM screen visible or not. The primary outcome was the median proportion of inflations during manual PPV (face mask or intubated) within the target range (Vte 4-8 mL/kg). There were 42 other prespecified monitor measurements and clinical outcomes. RESULTS: Among 288 infants randomised (median (IQR) gestational age 26+2 (25+3-27+1) weeks), a total number of 51,352 inflations were analysed. The median (IQR) percentage of inflations within the target range in the RFM visible group was 30.0 (18.0-42.2)% vs 30.2 (14.8-43.1)% in the RFM non-visible group (p = 0.721). There were no differences in other respiratory function measurements, oxygen saturation, heart rate or FiO2. There were no differences in clinical outcomes, except for the incidence of intraventricular haemorrhage (all grades) and/or cystic periventricular leukomalacia (visible RFM: 26.7% vs non-visible RFM: 39.0%; RR 0.71 (0.68-0.97); p = 0.028). CONCLUSION: In very preterm infants receiving PPV at birth, the use of a RFM, compared to no RFM as guidance for tidal volume delivery, did not increase the percentage of inflations in a predefined target range. TRIAL REGISTRATION: Dutch Trial Register NTR4104, clinicaltrials.gov NCT03256578.

Environmental Exposure during Pregnancy: Influence on Prenatal Development and Early Life: A Comprehensive Review.

Preconception and prenatal exposure to environmental contaminants may affect future health. Pregnancy and early life are critical sensitive windows of susceptibility. The aim of this review was to summarize current evidence on the toxic effects of environment exposure during pregnancy, the neonatal period, and childhood. Alcohol use is related to foetal alcohol spectrum disorders, foetal alcohol syndrome being its most extreme form. Smoking is associated with placental abnormalities, preterm birth, stillbirth, or impaired growth and development, as well as with intellectual impairment, obesity, and cardiovascular diseases later in life. Negative birth outcomes have been linked to the use of drugs of abuse. Pregnant and lactating women are exposed to endocrine-disrupting chemicals and heavy metals present in foodstuffs, which may alter hormones in the body. Prenatal exposure to these compounds has been associated with pre-eclampsia and intrauterine growth restriction, preterm birth, and thyroid function. Metals can accumulate in the placenta, causing foetal growth restriction. Evidence on the effects of air pollutants on pregnancy is constantly growing, for example, preterm birth, foetal growth restriction, increased uterine vascular resistance, impaired placental vascularization, increased gestational diabetes, and reduced telomere length. The advantages of breastfeeding outweigh any risks from contaminants. However, it is important to assess health outcomes of toxic exposures via breastfeeding. Initial studies suggest an association between pre-eclampsia and environmental noise, particularly with early-onset pre-eclampsia. There is rising evidence of the negative effects of environmental contaminants following exposure during pregnancy and breastfeeding, which should be considered a major public health issue.

Inter-center variability in neonatal outcomes of preterm infants: A longitudinal evaluation of 298 neonatal units in 11 countries.

Collaboration and cooperation of clinicians and neonatal units at regional, national, and international levels are key features of many networks or systems that aim to improve neonatal outcomes. Network performance is typically assessed by comparing individual, unit-level outcomes. In this paper, we provide insight into another dimension, i.e., inter-center outcome variation in 10 national/regional neonatal collaborations from 11 high-income countries. We illustrate the use of coefficients of variation for evaluation of mortality and a composite outcome of mortality, severe neurological injury, treated retinopathy of prematurity, and bronchopulmonary dysplasia, as a measure of inter-center variation. These inter-center variation estimates could help to identify areas of opportunities and challenges for each country/region; they also provide "macro"-level evaluations that can be useful for clinicians, administrators, managers and policy makers.

Analysis of Lipid Peroxidation by UPLC-MS/MS and Retinoprotective Effects of the Natural Polyphenol Pterostilbene.

The loss of redox homeostasis induced by hyperglycemia is an early sign and key factor in the development of diabetic retinopathy. Due to the high level of long-chain polyunsaturated fatty acids, diabetic retina is highly susceptible to lipid peroxidation, source of pathophysiological alterations in diabetic retinopathy. Previous studies have shown that pterostilbene, a natural antioxidant polyphenol, is an effective therapy against diabetic retinopathy development, although its protective effects on lipid peroxidation are not well known. Plasma, urine and retinas from diabetic rabbits, control and diabetic rabbits treated daily with pterostilbene were analyzed. Lipid peroxidation was evaluated through the determination of derivatives from arachidonic, adrenic and docosahexaenoic acids by ultra-performance liquid chromatography coupled with tandem mass spectrometry. Diabetes increased lipid peroxidation in retina, plasma and urine samples and pterostilbene treatment restored control values, showing its ability to prevent early and main alterations in the development of diabetic retinopathy. Through our study, we are able to propose the use of a derivative of adrenic acid, 17(RS)-10-epi-SC-Δ15-11-dihomo-IsoF, for the first time, as a suitable biomarker of diabetic retinopathy in plasmas or urine.

Neonatal outcomes of extremely preterm twins by sex pairing: an international cohort study.

OBJECTIVE: Infant boys have worse outcomes than girls. In twins, the 'male disadvantage' has been reported to extend to female co-twins via a 'masculinising' effect. We studied the association between sex pairing and neonatal outcomes in extremely preterm twins. DESIGN: Retrospective cohort study SETTING: Eleven countries participating in the International Network for Evaluating Outcomes of Neonates. PATIENTS: Liveborn twins admitted at 23-29 weeks' gestation in 2007-2015. MAIN OUTCOME MEASURES: We examined in-hospital mortality, grades 3/4 intraventricular haemorrhage or cystic periventricular leukomalacia (IVH/PVL), bronchopulmonary dysplasia (BPD), retinopathy of prematurity requiring treatment and a composite outcome (mortality or any of the outcomes above). RESULTS: Among 20 924 twins, 38% were from male-male pairs, 32% were from female-female pairs and 30% were sex discordant. We had no information on chorionicity. Girls with a male co-twin had lower odds of mortality, IVH/PVL and the composite outcome than girl-girl pairs (reference group): adjusted OR (aOR) (95% CI) 0.79 (0.68 to 0.92), 0.83 (0.72 to 0.96) and 0.88 (0.79 to 0.98), respectively. Boys with a female co-twin also had lower odds of mortality: aOR 0.86 (0.74 to 0.99). Boys from male-male pairs had highest odds of BPD and composite outcome: aOR 1.38 (1.24 to 1.52) and 1.27 (1.16 to 1.39), respectively. CONCLUSIONS: Sex-related disparities in outcomes exist in extremely preterm twins, with girls having lower risks than boys and opposite-sex pairs having lower risks than same-sex pairs. Our results may help clinicians in assessing risk in this large segment of extremely preterm infants.

Family Rooms in Neonatal Intensive Care Units and Neonatal Outcomes: An International Survey and Linked Cohort Study.

OBJECTIVES: To evaluate the proportion of neonatal intensive care units with facilities supporting parental presence in their infants' rooms throughout the 24-hour day (ie, infant-parent rooms) in high-income countries and to analyze the association of this with outcomes of extremely preterm infants. STUDY DESIGN: In this survey and linked cohort study, we analyzed unit design and facilities for parents in 10 neonatal networks of 11 countries. We compared the composite outcome of mortality or major morbidity, length of stay, and individual morbidities between neonates admitted to units with and without infant-parent rooms by linking survey responses to patient data from 2015 for neonates of less than 29 weeks of gestation. RESULTS: Of 331 units, 13.3% (44/331) provided infant-parent rooms. Patient-level data were available for 4662 infants admitted to 159 units in 7 networks; 28% of the infants were cared for in units with infant-parent rooms. Neonates from units with infant-parent rooms had lower odds of mortality or major morbidity (aOR, 0.76; 95% CI, 0.64-0.89), including lower odds of sepsis and bronchopulmonary dysplasia, than those from units without infant-parent rooms. The adjusted mean length of stay was 3.4 days shorter (95%, CI -4.7 to -3.1) in the units with infant-parent rooms. CONCLUSIONS: The majority of units in high-income countries lack facilities to support parents' presence in their infants' rooms 24 hours per day. The availability vs absence of infant-parent rooms was associated with lower odds of composite outcome of mortality or major morbidity and a shorter length of stay.

Neonatal Outcomes in Very Preterm Infants With Severe Congenital Heart Defects: An International Cohort Study.

Background Very preterm infants are at high risk of death or severe morbidity. The objective was to determine the significance of severe congenital heart defects (CHDs) for these risks. Methods and Results This cohort study included infants from 10 countries born from 2007-2015 at 24 to 31 weeks' gestation with birth weights <1500 g. Severe CHDs were defined by International Classification of Diseases, Ninth Revision (ICD-9) and Tenth (ICD-10) codes and categorized as those compromising systemic output, causing sustained cyanosis, or resulting in congestive heart failure. The primary outcome was in-hospital mortality. Secondary outcomes were neonatal brain injury, necrotizing enterocolitis, bronchopulmonary dysplasia, and retinopathy of prematurity. Adjusted and propensity score-matched odds ratios (ORs) were calculated. Analyses were stratified by type of CHD, gestational age, and network. A total of 609 (0.77%) infants had severe CHD and 76 371 without any malformation served as controls. The mean gestational age and birth weight were 27.8 weeks and 1018 g, respectively. The mortality rate was 18.6% in infants with CHD and 8.9% in controls (propensity score-matched OR, 2.30; 95% CI, 1.61-3.27). Severe CHD was not associated with neonatal brain injury, necrotizing enterocolitis, or retinopathy of prematurity, whereas the OR for bronchopulmonary dysplasia increased. Mortality was higher in all types, with the highest propensity score-matched OR (4.96; 95% CI, 2.11-11.7) for CHD causing congestive heart failure. While mortality did not differ between groups at <27 weeks' gestational age, adjusted OR for mortality in infants with CHD increased to 10.9 (95% CI, 5.76-20.70) at 31 weeks' gestational age. Rates of CHD and mortality differed significantly between networks. Conclusions Severe CHD is associated with significantly increased mortality in very preterm infants.

Oxygen in the neonatal period: Oxidative stress, oxygen load and epigenetic changes.

Preterm infants frequently require positive pressure ventilation and oxygen supplementation in the first minutes after birth. It has been shown that the amount of oxygen provided during stabilization, the oxygen load, if excessive may cause hyperoxia, and oxidative damage to DNA. Epidemiologic studies have associated supplementation with pure oxygen in the first minutes after birth with childhood cancer. Recent studies have shown that the amount of oxygen supplemented to preterm infants after birth modifies the epigenome. Of note, the degree of DNA hyper-or hypomethylation correlates with the oxygen load provided upon stabilization. If these epigenetic modifications would persist, oxygen supplied in the first minutes after birth could have long term consequences. Further studies with a robust power calculation and long-term follow up are needed to bear out the long-term consequences of oxygen supplementation during postnatal stabilization of preterm infants.

Intercenter variability and factors associated with survival without bronchopulmonary dysplasia in extremely preterm newborns.

Background: Variability in clinical practice may influence morbidity and mortality in extremely preterm infants. We aimed to know if there are differences in survival and survival without bronchopulmonary dysplasia (BPD) in extremely preterm infants in Spanish tertiary hospitals and the potential associated factors.Methods: Fifteen hospitals from the SEN1500 network were studied. The overall rate of survival without BPD was 61.4%. Hospitals with extreme results were grouped for comparison (Group 1; N = 2480 versus Group 2; N = 2367). A bivariate analysis of the characteristics of patients and perinatal interventions was carried out and the probability of survival without BPD was studied by Cox regression.Results: Survival (79.0 versus 72.9%; p < .001) and survival without BPD (72.5 versus 49.1%; p < .001) were greater in Group 1. Higher gestational age, birth weight, and female sex were associated with better outcomes. Oxygen administration (aHR: 0.868 [95%CI: 0.782, 0.964]; p=.008) and intubation (aHR: 0.767 [95%CI: 0.701, 0.839]; p < .001) in delivery room were associated with lower survival without BPD. The occurrence of patent ductus arteriosus (PDA), sepsis and/or necrotizing enterocolitis (NEC) was independently associated with worse outcomes. After adjusting for confounders, the probabilities of survival without BPD were significantly higher among patients in Group 1: aHR: 1.557 [95% CI: 1.458, 1.662]; p < .001.Conclusions: Among the studied hospitals, we found great variability in clinical practice and in the rates of survival and survival without BPD. A more conservative approach to the use of oxygen and respiratory support seems to be related to an increase in survival without BPD. Complications such as PDA, sepsis, and/or NEC decrease survival without BPD. Other variables not included in the present study could be relevant and deserve further study.

Biomonitoring of non-persistent pesticides in urine from lactating mothers: Exposure and risk assessment.

The aim of the present study was to assess the exposure to pesticides in urine from Spanish lactating mothers (n = 116). Six nonspecific (dialkyl phosphates) and 20 specific metabolites of organophosphate pesticides (OPs), herbicides and pyrethroids were analyzed. The most frequently detected biomarkers were diethyl phosphate, p-nitrophenol, 3,5,6-trichloro-2-pyridinol and 3-phenoxybenzoic acid, whose geometric means were 1.9 ng·mL-1, 0.8 ng·mL-1, 1.5 ng·mL-1 and 1.4 ng·mL-1, respectively. Herbicide metabolites were the least frequently detected biomarkers with detection frequencies between 0% (2,4,5-Trichlorophenoxyacetic acid) and 22% (2,4-Dichlorophenoxyacetic acid). Multiple regression analyses showed that the closeness to a farming activity, the place of residence and the presence of garden/plants at home were some of the most important contributors to urinary levels of pesticide metabolites. Estimated daily intake (EDI), hazard quotient (HQ) and hazard index (HI) were obtained in order to interpret urinary levels of the most frequently detected pesticide metabolites in a risk assessment context. The highest EDIs were obtained for chlorpyrifos (0.40-1.14 µg·kg bw-1·day-1) and deltamethrin (0.34-4.73 µg·kg bw-1·day-1). The calculated HQ for chlorpyrifos, dimethoate, parathion and deltamethrin ranged from 0.01 to 0.47, and HI for OPs ranged from 0.09 to 0.33 showing that apparently there were low health risks due to the exposure to these pesticides in this group of Spanish breastfeeding women.