Study of the pathophysiological mechanisms associated with the onset and course of neurodevelopmental disorders in preterm infants (the PeriSTRESS-PremTEA study): Rationale, objectives, design and sample description

BACKGROUND

There are few studies exploring the pathophysiological pathways that may condition differentially the emergence/course of neurodevelopmental disorders (ND) in very preterm and extremely preterm newborns (VPTN/EPTN). Furthermore, there are no established biological markers predictive of ND in this population. The aim of this study is four-fold: in two cohorts of VPTN/EPTN (i) to characterize the emergence/course of ND up to corrected-age 6 years, (ii) to identify those factors (from prenatal stages up to age 6 years) that explain the interindividual differences related to emergence/course of ND, (iii) to identify in the first hours/days of life a urinary metabolomic biomarker profile predictive of ND, and (iv) to determine longitudinally variations in DNA methylation patterns predictive of ND.

METHODS

Observational, longitudinal, prospective, six-year follow-up, multicentre collaborative study. Two cohorts are being recruited: the PeriSTRESS-Valencia-cohort (n=26 VPTN, 18 EPTN, and 122 born-at-term controls), and the PremTEA-Madrid-cohort (n=49 EPTN and n=29 controls).

RESULTS

We describe the rationale, objectives and design of the PeriSTRESS-PremTEA project and show a description at birth of the recruited samples.

CONCLUSIONS

The PeriSTRESS-PremTEA project could help improve early identification of clinical, environmental and biological variables involved in the physiopathology of ND in VPTN/EPTN. It could also help to improve the early identification of non-invasive ND biomarkers in this population. This may allow early ND detection as well as early and personalised intervention for these children.

Antenatal magnesium sulphate and delayed passage of meconium: A multicentre study

INTRODUCTION

The published evidence on the association between magnesium sulphate (MgSO₄) and delayed passage of meconium (DPM) is contradictory.

OBJECTIVES

To determine whether there is an association between the administration of MgSO₄ to the mother and DPM in the neonate, and to analyse serum magnesium levels in neonates in relation to the cumulative dose of MgSO₄ administered to the mother.

POPULATION AND METHODS

Retrospective and prospective descriptive and analytical study conducted in patients delivered at or before 32 weeks of gestation in 2 tertiary care hospitals. Delayed passage of meconium was defined as failure to pass meconium within 48 h of birth and/or need for rectal stimulation on 2 or more occasions to pass stool and/or interval of at least 48 h between the first and second bowel movements.

RESULTS

The study included 283 patients (204 retrospectively and 79 prospectively), of who 152 (53.7%) experienced DPM. Delayed passage of meconium was not associated with antenatal MgSO₄ administration, the cumulative maternal MgSO4 dose or neonatal serum magnesium levels. Older gestational age (OR, 0.8; confidence interval [CI], 0.69-0.93; P = 0.003) was an independent protective factor against DPM, while the need for advanced resuscitation (OR, 2.24; CI 1.04-4.86; P = 0.04) was a risk factor for DPM.

CONCLUSION

The neonatal serum levels of magnesium reached with the doses of MgSO₄ administered to mothers were not associated with DPM. Lower gestational age and the need for advanced resuscitation were predictors associated with an increased risk of DPM.

Prognostic value of somatosensory-evoked potentials in the newborn with hypoxic-ischemic encephalopathy after the introduction of therapeutic hypothermia

To establish the ability of somatosensory-evoked potentials (SEPs) to detect neurological damage in neonatal patients with hypoxic-ischemic encephalopathy (HIE) treated with therapeutic hypothermia (TH). Retrospective study including 84 neonates ≥ 36 weeks of gestational age with HIE and TH with SEPs performed in the first 14 days of life. SEPs from the median nerve were performed after completion of TH. Either unilateral or bilateral absence of N20, or unilateral or bilateral latency ≥ 36 ms, was considered pathological. All newborns underwent a cerebral resonance imaging (MRI) at between days 7 and 14 of life and a neurodevelopmental evaluation using the Brunet-Lezine test at two years of age; a global Brunet-Lezine test score < 70 was considered unfavorable. The risk of moderate-to-severe alteration on basal ganglia-thalamic (BGT) and/or white matter areas on MRI for pathological SEPs was as follows: odds ratio 95% IC: 23.1 (6.9-76.9), sensitivity 78.6%, specificity 86.3%, positive predictive value 75.9%, and negative predictive value 88%. The BGT and internal capsule were the areas with the greatest risk of lesion with an altered SEPs: odds ratio 95% IC 93.1 (11.1-777.8). The risk of neurodevelopmental impairment for pathological SEPs was odds ratio 95% IC: 38.5 (4.4-335.3), sensitivity 91.7%, specificity 77.8% positive predictive value 52.4%, and negative predictive value 97.2%.

CONCLUSION

The present study demonstrates the good predictive capacity of SEPs performed in the first two weeks of life in newborns with HIE and TH to detect an increased risk of neuroimaging lesions and neurodevelopmental impairment at two years of age.

WHAT IS KNOWN

• Bilateral absence of the N20 cortical component of somatosensory evoked potentials has been associated with poor neurological outcome in neonates with hypoxic-ischemic encephalopathy.

WHAT IS NEW

• This work confirms the predictive capacity of SEPs by adding two important aspects: the value of latency when interpreting SEPs results and the absence of effect of the hypothermia method used on the results of SEPs.

[Prenatal therapy with magnesium sulphate and intestinal obstruction due to meconium in preterm newborns]

INTRODUCTION

Magnesium sulphate (MgSO4) therapy has shown to be useful as a neurological protector in the preterm newborn below 32 weeks of gestation. The most documented adverse effect is cardiorespiratory failure, whereas its relationship with meconium obstruction is controversial. The main objective of this study was to analyse the possible association between prenatal MgSO4 therapy and meconium obstruction.

PATIENTS AND METHODS

An analytical retrospective study was conducted on < 32 weeks preterm babies admitted to a tertiary-level hospital (January 2016-December 2017). Epidemiological, prenatal and postnatal data on the outcomes were obtained, analysed and compared in both groups (exposed to MgSO4 and not exposed).

RESULTS

The study included 201 patients (146 exposed and 55 non-exposed). There were no significant differences in the mean gestational age (28.4 ± 2.2 vs. 28.7 ± 2.8 weeks, respectively), or in the rest of epidemiological and perinatal variables. Prenatal corticosteroid therapy was more frequent in the MgSO4 group (75.9 vs. 53.7%; p = .002), and in the non-exposed group there were more multiple pregnancies (52.7 vs. 36.6%; p = .027), and female gender (56.4 vs. 37%; p = .013). There were no statistically significant differences in the presence of meconium obstruction (75.9% in exposed vs. 67.3% in non-exposed; p = .23), although repeated rectal stimulation was more frequent in the exposed group (43.2 vs. 27.9%; p = .08). Furthermore, there were no significant differences in the main cardiorespiratory variables: 1-minute Apgar score (6.2 in MgSO4- exposed vs. 5.6 in non-exposed; p = .75), 5-minutes Apgar score (7.9 vs. 7.6; p = .31), advanced newborn resuscitation (26 vs. 31.5%; p = .44), maximum FiO2 (45.5 vs. 48; p = .58), and initial inotropic requirements (10.3 vs. 20.8%; p = .55).

CONCLUSIONS

This study found no correlations between MgSO4 therapy and meconium obstruction or cardiorespiratory failure.