Extremely and very preterm children who were born appropriate for gestational age show no differences in cortisol concentrations or diurnal rhythms compared to full-term children

OBJECTIVES

The objective of this study was to compare the diurnal variations in cortisol and cortisone concentrations in serum and saliva among extremely preterm (EPT), very preterm (VPT), and full-term (FT) children, all born appropriate for gestational age (AGA).

METHODS

EPT, VPT, and FT children, all born AGA, were recruited from two healthcare centers. Cortisol and cortisone concentrations in serum and saliva were measured by liquid chromatography-mass spectrometry (LC‒MS). Statistical analysis was performed using nonparametric tests.

RESULTS

A total of 101 children (5.0-8.9 years old) were included in this study: EPT=18, VPT=43 and FT=40. All groups had similar distributions in terms of age, birth weight standard deviation score (SDS) and BMI (SDS), showing no differences in serum ACTH, cortisol, or cortisone levels. Additionally, salivary cortisol and cortisone concentrations decreased significantly throughout the day (p-values<0.0001). Salivary cortisol concentrations were below the limit of detection (0.55 nmol/L) before dinner and before bedtime in approximately one-third and two-thirds of all children, respectively. Salivary cortisone was detectable in all but one sample.

CONCLUSIONS

The diurnal cortisol rhythm was preserved in all preterm children, regardless of their gestational age, and no differences in cortisol concentrations among the groups were found. This may have significant implications for the clinical management and follow-up of preterm individuals.

Insulin resistance parameters in children born very preterm and adequate for gestational age

BACKGROUND

Preterm neonates are at risk for metabolic syndrome later in life. Whether prematurity constitutes an independent risk factor for the development of cardiovascular disease and metabolic syndrome remains controversial.

OBJECTIVE

To compare anthropometric measures, cardiometabolic risk factors and insulin resistance variables between children who were born very preterm (VPT, <32 gestational weeks) and at term (Term, >37 gestational weeks) and adequate for gestational age (AGA).

METHODS

We designed a cross-sectional cohort study, recruiting 120 children (5.0-8.5 years old) from the preterm clinic at Red de Salud UC-Christus and Complejo Asistencial Dr. Sótero del Río, and term children from the community. We excluded children born small for gestational age, based on INTERGROWTH21. Anthropometrics data were classified using WHO reference standards. The homeostasis model assessment insulin resistance (HOMA-IR) index, quantitative insulin sensitivity check index (QUICKI), triglyceride-to-HDL-C ratio (TG/HDL-C) and Pediatric Score Index for Metabolic Syndrome (PsiMS) were calculated.

RESULTS

VPT children born AGA had lower HDL cholesterol levels (p = .019) and a higher PsiMS score than those born at term (p = .043). We observed a higher percentage of children with HDL cholesterol ≤40 mg/dl (13.0% vs. 2.3%, p = .026) and BP ≥90th percentile among the VPT children than among the Term children (26.0% vs. 11.6%, p = .031).

CONCLUSIONS

At school age, blood pressure was higher, and HDL-C was lower among VPT children born AGA, suggesting a potential metabolic risk; therefore, it is essential to follow this group throughout their lives.

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.

Perinatal antecedents of sleep disturbances in schoolchildren

STUDY OBJECTIVES

Prematurity has been associated with an increased risk for sleep apnea. However, sleep disturbances in children born preterm have not been extensively investigated. Considering that determinants of sleep may originate early in life, the potential impact of prematurity on sleep disturbances later in life could be important. To establish the role of prematurity on sleep disturbances in a cohort of schoolchildren that were born preterm and compare them with healthy controls.

METHODS

A cohort of 147 schoolchildren, 45 born at term (≥37 weeks) and 102 very preterm (<32 weeks), was recruited and evaluated at school age (5-9 years). The Pediatric Sleep Questionnaire (PSQ) and the Sleep Disturbance Scale for Children (SDSC) were used to assess sleep disturbances in different domains.

RESULTS

PSQ score was significantly higher in former preterm children (0.26 ± 0.18 vs. 0.18 ± 0.14 in controls; p = 0.004), and SDSC total score was also significantly different among groups (21.7 ± 11.6 vs. 14.1 ± 12.6; p < 0.001). Regression models showed significant mean differences in PSQ score, total SDSC score, and two SDSC subscale scores (i.e. sleep-wake transition disorders, sleep-breathing disorders, and sleep hyperhidrosis) even after adjustment for confounders. Maternal age and type of delivery were not significantly associated with total PSQ scores.

CONCLUSIONS

Sleep disturbances may originate early in life since children born preterm exhibit an increased risk for developing long-term sleep problems. These findings may have important implications for management of preterm children and for implementation of early interventions focused on optimizing sleep habits.

The unfinished work of neonatal very low birthweight infants quality improvement: Improving outcomes at a continental level in South America

Neonatal mortality rate varies between 4.2 and 18.6 per thousand by country in South America. There is little information regarding the outcomes of very low birth weight infants in the region and mortality rates are extremely variable ranging from 6% to over 50%. This group may represent up to 50-70% of the neonatal mortality and approximately 25-30% of infant mortality. Some initiatives, like the NEOCOSUR Network, have systematically collected and analyzed epidemiological information on VLBW infants' outcomes in the region. Over a 16-year period, survival without major morbidity improved from 37 to 44%. However, mortality has remained almost unchanged at approximately 27%, despite an increase in the implementation of the best available evidence in perinatal practices over time. Implementing quality improvement initiatives in the continent is particularly challenging but represents a great opportunity considering that there is a wide margin for progress in both care and outcomes.

Factors Associated with Survival and Survival without Major Morbidity in Very Preterm Infants in Two Neonatal Networks: SEN1500 and NEOCOSUR

INTRODUCTION

Very low-birth weight (VLBW) infants represent a high-risk population for morbidity and mortality in the neonatal period. Variability in practices and outcomes between centers has been acknowledged. Multicenter benchmarking studies are useful to detect areas of improvement and constitute an interesting research tool.

OBJECTIVES

The aim of the study was to determine the perinatal variables and interventions associated with survival and survival without major morbidity in VLBW infants and compare the performance of 2 large networks.

METHODS

This is a prospective study analyzing data collected in 2 databases, the Spanish SEN1500 and the South American NEOCOSUR networks, from January 2013 to December 2016. Inborn patients, from 240 to 306 weeks of gestational age (GA) were included. Hazard ratios for survival and survival without major morbidity until the first hospital discharge or transfer to another facility were studied by using Cox proportional hazards regression.

RESULTS

A total of 10,565 patients, 6,120 (57.9%) from SEN1500 and 4,445 (42.1%) from NEOCOSUR, respectively, were included. In addition to GA, birth weight, small for gestational age (SGA), female sex, and multiple gestation, less invasive resuscitation, and the network of origin were significant independent factors influencing survival (aHR [SEN1500 vs. NEOCOSUR]: 1.20 [95% CI: 1.15-1.26] and survival without major morbidity: 1.34 [95% CI: 1.26-1.43]). Great variability in outcomes between centers was also found within each network.

CONCLUSIONS

After adjusting for covariates, GA, birth weight, SGA, female sex, multiple gestation, less invasive resuscitation, and the network of origin showed an independent effect on outcomes. Determining the causes of these differences deserves further study.

[Seasonal variations in 25-hydroxy vitamin D3, parathormone and alkaline phosphatase in school-aged children]

INTRODUCTION

The main role of Vitamin D is to regulate calcium metabolism, whose main source is vitamin D3 ob tained mostly from the action of ultraviolet (UV) light on the skin.

OBJECTIVE

To evaluate the seaso nal differences in the concentrations of 25-hydroxy-vitamin D3 (25OHVitD3), parathyroid hormone (PTH), alkaline phosphatase (ALP), and calcium in school-age children.

SUBJECTS AND METHOD

The concentrations of 25OHVitD3, PTH, ALP, and calcium were measured in children from Santiago, Chile (latitude -33.4372), aged 5 to 8 years, without Vitamin D supplementation, in different seasons of the year. VitD status was defined as sufficient with concentrations of 25OHVitD3 >20 ng/mL (50 nmol/L), insufficient 12-20 ng/mL (30-50 nmol/L) and deficient <12 ng/mL (30 nmol/L) based on the recommendations of the expert group of the "Global Consensus for the Prevention and Mana gement of Nutritional Rickets".

RESULTS

133 children participated (89 preterms under or equal to 32 weeks), 41 during summer, 28 in fall, 35 in winter, and 29 in spring. The difference of means between summer and winter was 9.6 ng/mL for 25OHVitD3 (p <0.0001), -11.1 pg/mL for PTH (p <0.0001), and -47.5 IU/mL for ALP (p= 0.01). There were no differences in calcium concentrations. In sum mer, 97.6% of the subjects were classified with sufficiency status (> 20 ng/mL), which decreased significantly in winter to 54.3% (p <0.0001).

CONCLUSIONS

In winter, 25OHVitD3 concentrations decreased in approximately half of the children, which was associated with an increase in PTH and ALP, and normal calcium concentrations. According to our results, children may need VitD supple mentation during fall and winter.

Trends in Perinatal Practices and Neonatal Outcomes of Very Low Birth Weight Infants during a 16-year Period at NEOCOSUR Centers

OBJECTIVE

To describe trends in mortality, major morbidity, and perinatal care practices of very low birth weight infants born at NEOCOSUR Neonatal Network centers from January 1, 2001, through December 31, 2016.

STUDY DESIGN

A retrospective analysis of prospectively collected data from all inborn infants with a birthweight of 500-1500 g and 23-35 weeks of gestation.

RESULTS

We examined data for 13 987 very low birth weight infants with a mean birth weight of 1081 ± 281 g and a gestational age of 28.8 ± 2.9 weeks. Overall mortality was 26.8% without significant changes throughout the study period. Decreases in early onset sepsis from 6.3% to 2.8% (P <.001), late onset sepsis from 21.1% to 19.5% (P = .002), retinopathy of prematurity from 21.3% to 13.8% (P <.001), and hydrocephalus from 3.8% to 2.4% (P <.001), were observed. The incidence for bronchopulmonary dysplasia decreased from 17.3% to 16% (P = .043), incidence of severe intraventricular hemorrhage was 10.4%, necrotizing enterocolitis 11.1%, and periventricular leukomalacia 3.8%, and did not change over the study period. Administration of antenatal corticosteroids increased from 70.2% to 82.3% and cesarean delivery from 65.9% to 75.4% (P <.001). The use of conventional mechanical ventilation decreased from 67.7% to 63.9% (P <.001) and continuous positive airway pressure use increased from 41.3% to 64.3% (P <.001). Survival without major morbidity increased from 37.4% to 44.5% over the study period (P <.001).

CONCLUSIONS

Progress in perinatal and neonatal care at network centers was associated with an improvement in survival without major morbidity of very low birth weight infants during a 16-year period. However, overall mortality remained unchanged.

Survival and morbidity of very low birth weight infant in a South American neonatal network

OBJECTIVE

To analyze survival and relevant morbidity by gestational age (GA) in very low birth weight (VLBW) infants (<1500 g) and, based on these data, develop a fact sheet to provide information to perinatal healthcare providers and very low birth weight preterm infants' parents.

STUDY DESIGN

Data were prospectively collected in relation to newborn infants with a birth weight between 500 g and 1500 g admitted to 45 sites of the Neocosur Neonatal Network (Red Neonatal Neocosur) between January 2001 and December 2011.

RESULTS

Data on 8234 VLBW with a GA between 24+0 and 31+6 weeks were analyzed. Overall mortality was 26% (95% CI: 25.0-26.9), including 2.6% of deaths in the delivery room. Fact sheets for survival and morbidity for each week of gestation were developed based on collected data. Survival at discharge increased from 29% at 24 weeks of GA to 91% at 31 weeks of GA (p < 0.001). The incidence of relevant neonatal morbidity was inversely related to GA (p < 0.001). Overall, 30.8% had retinopathy of prematurity, 25% bronchopulmonary dysplasia, 10.9% necrotizing enterocolitis, 7.2% severe intraventricular hemorrhage, and 4.6% periventricular leukomalacia. Among survivors, 47.3% had none of these five conditions.

CONCLUSIONS

A tool for use in a clinical setting was developed based on updated regional data for establishing week-to-week survival and morbidity of newborn infants born between 24+0 and 31+6 weeks of GA. This information could be used to make decisions related to perinatal care and for counseling parents.

Center variability in risk of adjusted length of stay for very low birth weight infants in the Neocosur South American Network

OBJECTIVES

To develop a prediction model for hospital length of stay (LOS) in very low birth weight (VLBW) infants and to compare this outcome among 20 centers within a neonatal network.

METHODS

Data from 7,599 infants with birth weights of 500-1,500 g born between the years 2001-2008 were prospectively collected. The Cox regression model was employed to develop two prediction models: an early model based upon variables present at birth, and a late one that adds relevant morbidities for the first 30 days of life.

RESULTS

Median adjusted estimated LOS from birth was 59 days - 28 days after 30-day point of survival. There was a high correlation between models (r = 0.92). Expected/observed LOS varied widely among centers, even after correction for relevant morbidity after 30 days. Median observed LOS (range: 45-70 days), and postmenstrual age at discharge (range: 36.4-39.9 weeks) reflect high inter-center variability.

CONCLUSION

A simple model, with factors present at birth, can predict a VLBW infant's LOS in a neonatal network. Significant variability in LOS was observed among neonatal intensive care units. We speculate that the results originate in differences in inter-center practices.

[Impact of respiratory distress syndrome in very low birth weight infants: a multicenter South-American study]

OBJECTIVE

To analyze the incidence, risk factors, major morbidity, mortality and resource employment in very low birth weight infants (< 1500 g) with respiratory distress syndrome (RDS).

METHODS

Descriptive study using prospectively obtained on-line information from a data base of 20 units belonging to the South American Neocosur Network. A total of 5991 VLBW infants were registered during years 2002-2007.

RESULTS

The mean gestacional age was 29.1 weeks (95% CI 29.06-29.21) and the mean of birth weight was 1100.5 g (95% CI 1093.79-1107.37). The global incidence of RDS was 74% (95% CI 73-75). Antenatal steroids were administered to 73% of this population. The main risk factor was lower gestational age (p< 0.001); where as prenatal steroids (OR: 0.59; 95% CI 0.49-0.72), female gender (OR: 0.77; 95% CI 0.67-0.89) and premature rupture of membranes (OR: 0.81; 95% CI 0.68-0.96) were protective factors. Antenatal steroids was also associated with a decrease in mortality in those infants that presented with RDS (OR: 0.40; 95% CI 0.34-0.47). Use of resources was higher in the group with RDS, with a greater use of surfactant (74.3% vs. 7.3%, p< 0.001), mechanical ventilation (82.1% vs. 23.8%, p< 0.001), and more days of oxygen (median of 8 vs. 1 day, p< 0.001) and hospitalization (median of 61 vs. 45 days, p< 0.001). RDS was associated to an increase risk in the incidence of ROP, PDA, late onset sepsis, severe IVH and oxygen requirement at 36 weeks of corrected gestational age.

CONCLUSIONS

RDS had a high incidence in very low birth weight infants, despite the frequent use of antenatal steroids. VLBW Infants with RDS had a higher mortality and an increase risk of relevant morbidity. RDS also increased use of resources.

Randomized controlled trial of early compared with delayed use of inhaled nitric oxide in newborns with a moderate respiratory failure and pulmonary hypertension

OBJECTIVE

To evaluate whether early treatment with inhaled nitric oxide (iNO) will prevent newborns with moderate respiratory failure from developing severe hypoxemic respiratory failure (oxygenation index (OI)>or=40).

STUDY DESIGN

A total of 56 newborns with moderate respiratory failure (OI between 10 and 30) were randomized before 48 h after birth to early treatment with 20 p.p.m. of iNO (Early iNO group, n=28) or conventional mechanical ventilation with FiO(2) 1.0 (Control group, n=28). Infants received iNO and/or high-frequency oscillatory ventilation (HFOV) if they developed an OI>40.

RESULT

7 of 28 early iNO patients (25%) compared to 17 of 28 control patients (61%) developed an OI>40 (P<0.05). In the Early iNO group mean OI significantly decreased from 22 (baseline) to 19 at 4 h (P<0.05) and remained lower over time: 19 (12 h), 18 (24 h) and 16 at 48 h. In contrast, OI increased in the Control group and remained significantly higher than the Early iNO group during the first 48 h of study: 22 (baseline), 29, 35, 32 and 23 at 4, 12, 24 and 48 h, respectively (P<0.01). Of 17, 6 control patients who developed an OI>40 were successfully treated with iNO. Nine of the remaining eleven control patients and six of seven Early iNO patients who had an OI>40 despite use of iNO responded with the addition of HFOV. One patient of the Early iNO group and two of the Control group died. Median (range) duration of oxygen therapy was significantly shorter in the Early iNO group: 11.5 (5 to 90) days compared to 18 (6 to 142) days of the Control group (P<0.03).

CONCLUSION

Early use of iNO in newborns with moderate respiratory failure improves oxygenation and decreases the probability of developing severe hypoxemic respiratory failure.

A new score for predicting neonatal very low birth weight mortality risk in the NEOCOSUR South American Network

OBJECTIVE

To develop and validate a model for very low birth weight (VLBW) neonatal mortality prediction, based on commonly available data at birth, in 16 neonatal intensive care units (NICUs) from five South American countries.

STUDY DESIGN

Prospectively collected biodemographic data from the Neonatal del Cono Sur (NEOCOSUR) Network between October 2000 and May 2003 in infants with birth weight 500 to 1500 g were employed. A testing sample and crossvalidation techniques were used to validate a statistical model for risk of in-hospital mortality. The new risk score was compared with two existing scores by using area under the receiver operating characteristic curve (AUC).

RESULTS

The new NEOCOSUR score was highly predictive for in-hospital mortality (AUC=0.85) and performed better than the Clinical Risk Index for Babies (CRIB) and the NICHD risk models when used in the NEOCOSUR Network. The new score is also well calibrated - it had good predictive capability for in-hospital mortality at all levels of risk (HL test=11.9, p=0.85). The new score also performed well when used to predict in hospital neurological and respiratory complications.

CONCLUSIONS

A new and relatively simple VLBW mortality risk score had a good prediction performance in a South American network population. This is an important tool for comparison purposes among NICUs. This score may prove to be a better model for application in developing countries.