Caffeine and kidney function at two years in former extremely low gestational age neonates.

BACKGROUND: Extremely low gestational age neonates (ELGANs) are at risk for chronic kidney disease. The long-term kidney effects of neonatal caffeine are unknown. We hypothesize that prolonged caffeine exposure will improve kidney function at 22-26 months. METHODS: Secondary analysis of the Preterm Erythropoietin Neuroprotection Trial of neonates <28 weeks' gestation. Participants included if any kidney outcomes were collected at 22-26 months corrected age. Exposure was post-menstrual age of caffeine discontinuation. PRIMARY OUTCOMES: 'reduced eGFR' <90 ml/min/1.73 m2, 'albuminuria' (>30 mg albumin/g creatinine), or 'elevated blood pressure' (BP) >95th %tile. A general estimating equation logistic regression model stratified by bronchopulmonary dysplasia (BPD) status was used. RESULTS: 598 participants had at least one kidney metric at follow up. Within the whole cohort, postmenstrual age of caffeine discontinuation was not associated with any abnormal measures of kidney function at 2 years. In the stratified analysis, for each additional week of caffeine, the no BPD group had a 21% decreased adjusted odds of eGFR <90 ml/min/1.73m2 (aOR 0.78; CI 0.62-0.99) and the BPD group had a 15% increased adjusted odds of elevated BP (aOR 1.15; CI: 1.05-1.25). CONCLUSIONS: Longer caffeine exposure during the neonatal period is associated with differential kidney outcomes at 22-26 months dependent on BPD status. IMPACT: In participants born <28 weeks' gestation, discontinuation of caffeine at a later post menstrual age was not associated with abnormal kidney outcomes at 22-26 months corrected age. When assessed at 2 years of age, later discontinuation of caffeine in children born <28 weeks' gestation was associated with a greater risk of reduced eGFR in those without a history of BPD and an increased odds of hypertension in those with a history of BPD. More work is necessary to understand the long-term impact of caffeine on the developing kidney.

Placental Erythroferrone and Erythropoietin mRNA Expression is not Associated with Maternal or Neonatal Iron Status in Adolescents Carrying Singletons and Adult Women Carrying Multiples.

BACKGROUND: The iron regulatory hormones erythroferrone (ERFE), erythropoietin (EPO), and hepcidin, and the cargo receptor nuclear receptor coactivator 4 (NCOA4) are expressed in the placenta. However, determinants of placental expression of these proteins and their associations with maternal or neonatal iron status are unknown. OBJECTIVES: To characterize expression of placental ERFE, EPO, and NCOA4 mRNA in placentae from newborns at increased risk of iron deficiency and to evaluate these in relation to maternal and neonatal iron status and regulatory hormones. METHODS: Placentae were collected from 114 neonates born to adolescents carrying singletons (14-18 y) and 110 neonates born to 54 adults (20-46 y) carrying multiples. Placental EPO, ERFE, and NCOA4 mRNA expression were measured by RT-qPCR and compared with maternal and neonatal iron status indicators (SF, sTfR, total body iron, serum iron) and hormones. RESULTS: Placental ERFE, EPO, and NCOA4 mRNA were detected in all placentae delivered between 25 and 42 wk of gestation. Relationships between placental ERFE and EPO differed by cohort. In the multiples cohort, placental EPO and ERFE were positively correlated (P = 0.004), but only a positive trend (P = 0.08) was evident in the adolescents. Placental EPO and ERFE were not associated with maternal or neonatal iron status markers or hormones in either cohort. Placental NCOA4 was not associated with placental EPO or ERFE in either cohort but was negatively associated with maternal SF (P = 0.03) in the multiples cohort and positively associated with neonatal sTfR (P = 0.009) in the adolescents. CONCLUSIONS: The human placenta expresses ERFE, EPO, and NCOA4 mRNA as early as 25 wk of gestation. Placental expression of ERFE and EPO transcripts was not associated with maternal or neonatal iron status. Greater placental NCOA4 transcript expression was evident in women and newborns with poor iron status (lower SF and higher sTfR, respectively). Further research is needed to characterize the roles of these proteins in the human placenta. TRIAL REGISTRATION NUMBER: These clinical trials were registered at clinicaltrials.gov as NCT01019902 (https://clinicaltrials.gov/ct2/show/NCT01019902) and NCT01582802 (https://clinicaltrials.gov/ct2/show/NCT01582802).

Placental Iron Content Is Lower than Previously Estimated and Is Associated with Maternal Iron Status in Women at Greater Risk of Gestational Iron Deficiency and Anemia.

BACKGROUND: Based on limited data, it is estimated that the placenta retains 90 mg of iron. Little is known about determinants of placental iron content. Animal data indicate that the placenta prioritizes iron for its own needs, but this hypothesis has not been evaluated in humans. OBJECTIVES: To characterize placental iron content and placental iron concentration (p[Fe]) in pregnant women at risk of iron insufficiency and identify determinants of p[Fe]. METHODS: Placentas were collected from 132 neonates born to teens carrying singletons (≤18 y) and 101 neonates born to 48 women carrying multiples (20-46 y). Maternal and neonatal iron status indicators [hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), serum iron, total body iron (TBI)] and hormones (erythropoietin, hepcidin) were measured. p[Fe] was measured using inductively coupled plasma-mass spectrometry. Correlation analyses and mixed-effects models were constructed to identify determinants of p[Fe]. RESULTS: Mean placental iron content was 23 mg per placenta (95% CI: 15, 33 mg) in the multiples and 40 mg (95% CI: 31, 51 mg) in the teens (P = 0.03). Mean p[Fe] did not differ between the cohorts. p[Fe] was higher in anemic (175 µg/g; 95% CI: 120, 254 µg/g) compared with nonanemic (46 µg/g; 95% CI: 26, 82 µg/g) women carrying multiples (P = 0.009), but did not differ between anemic (62 µg/g; 95% CI: 40, 102 µg/g) and nonanemic (73 µg/g; 95% CI: 56, 97 µg/g) teens. In women carrying multiples, low maternal iron status [lower SF (P = 0.002) and lower TBI (P = 0.01)] was associated with higher p[Fe], whereas in teens, improved iron status [lower sTfR (P = 0.03) and higher TBI (P = 0.03)] was associated with higher p[Fe]. CONCLUSIONS: Placental iron content was ∼50% lower than previously estimated. p[Fe] is significantly associated with maternal iron status. In women carrying multiples, poor maternal iron status was associated with higher p[Fe], whereas in teens, improved iron status was associated with higher p[Fe]. More data are needed to understand determinants of p[Fe] and the variable iron partitioning in teens compared with mature women.

The Effect of a Short Course of Tocolytic Indomethacin on Urinary Biomarkers in Premature Infants.

OBJECTIVE: The aim of this study was to determine the effects of a 2-day prenatal course of indomethacin on the premature kidney as reflected by serum creatinine and urinary biomarkers. STUDY DESIGN: Urine of infants ≤32 weeks was collected for the first 14 days and analyzed for cystatin C, neutrophil gelatinase-associated lipocalin, osteopontin, ß2 microglobulin, epidermal growth factor, uromodulin, and microalbumin. Bivariate analysis compared serum creatinine and biomarkers of exposed (INDO) and unexposed (CONT) subjects. RESULTS: Fifty-seven infants (35 CONT and 22 INDO) were studied. The cohorts were similar in gestational age, birthweight, race, gender, nephrotoxic medication exposure, and Apgar's scores. CONT had more dopamine exposure and included more pre-eclamptic mothers (p = 0.005). No difference in creatinine-based acute kidney injury or the log transformed mean, maximum, and minimum values of urinary biomarkers was detected. CONCLUSION: Our findings suggest that a short course of tocolytic indomethacin does not result in neonatal acute kidney injury. KEY POINTS: · A short prenatal course of indomethacin does not result in neonatal acute kidney injury (AKI).. · Urinary EGF might have a promising role as a more sensitive biomarker for early detection of AKI in premature infants..

Maternal Hypertension Disorders and Neonatal Acute Kidney Injury: Results from the AWAKEN Study.

OBJECTIVE: This study aimed to examine the association between maternal hypertension (HTN) exposure and neonatal acute kidney injury (AKI). STUDY DESIGN: Retrospective cohort study of 2,162 neonates admitted to 24 neonatal intensive care units (NICUs). Neonates were classified into the following exposure groups: any maternal HTN, chronic maternal HTN, preeclampsia/eclampsia, both, or neither. Demographics, clinical characteristics, and AKI status were compared using Chi-square and analysis of variance. General estimating logistic regression was used to estimate adjusted odds ratios and included a stratified analysis for site of delivery. RESULT: Neonates exposed to any maternal HTN disorder had a tendency toward less overall and early AKI. When stratified by inborn versus outborn, exposure to both maternal HTN disorders was associated with a significantly reduced odds of early AKI only in the inborn neonates. CONCLUSION: Exposure to maternal HTN, especially preeclampsia/eclampsia superimposed on chronic HTN, was associated with less likelihood of early AKI in the inborn group. KEY POINTS: · Maternal HTN is associated with less neonatal AKI.. · Maternal HTN category is variably associated with AKI.. · Inborn status is an important contributor to this association..

Limitations of Conventional Magnetic Resonance Imaging as a Predictor of Death or Disability Following Neonatal Hypoxic-Ischemic Encephalopathy in the Late Hypothermia Trial.

OBJECTIVE: To investigate if magnetic resonance imaging (MRI) is an accurate predictor for death or moderate-severe disability at 18-22 months of age among infants with neonatal encephalopathy in a trial of cooling initiated at 6-24 hours. STUDY DESIGN: Subgroup analysis of infants ≥36 weeks of gestation with moderate-severe neonatal encephalopathy randomized at 6-24 postnatal hours to hypothermia or usual care in a multicenter trial of late hypothermia. MRI scans were performed per each center's practice and interpreted by 2 central readers using the Eunice Kennedy Shriver National Institute of Child Health and Human Development injury score (6 levels, normal to hemispheric devastation). Neurodevelopmental outcomes were assessed at 18-22 months of age. RESULTS: Of 168 enrollees, 128 had an interpretable MRI and were seen in follow-up (n = 119) or died (n = 9). MRI findings were predominantly acute injury and did not differ by cooling treatment. At 18-22 months, death or severe disability occurred in 20.3%. No infant had moderate disability. Agreement between central readers was moderate (weighted kappa 0.56, 95% CI 0.45-0.67). The adjusted odds of death or severe disability increased 3.7-fold (95% CI 1.8-7.9) for each increment of injury score. The area under the curve for severe MRI patterns to predict death or severe disability was 0.77 and the positive and negative predictive values were 36% and 100%, respectively. CONCLUSIONS: MRI injury scores were associated with neurodevelopmental outcome at 18-22 months among infants in the Late Hypothermia Trial. However, the results suggest caution when using qualitative interpretations of MRI images to provide prognostic information to families following perinatal hypoxia-ischemia. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00614744.

Umbilical Cord Erythroferrone Is Inversely Associated with Hepcidin, but Does Not Capture the Most Variability in Iron Status of Neonates Born to Teens Carrying Singletons and Women Carrying Multiples.

BACKGROUND: The developing fetus requires adequate iron and produces its own hormones to regulate this process. Erythroferrone (ERFE) is a recently identified iron regulatory hormone, and normative data on ERFE concentrations and relations between iron status and other iron regulatory hormones at birth are needed. OBJECTIVES: The objective of this study was to characterize cord ERFE concentrations at birth and assess interrelations between ERFE, iron regulatory hormones, and iron status biomarkers in 2 cohorts of newborns at higher risk of neonatal anemia. METHODS: Umbilical cord ERFE concentrations were measured in extant serum samples collected from neonates born to women carrying multiples (age: 21-43 y; n = 127) or teens (age: 14-19 y; n = 164). Relations between cord blood ERFE and other markers of iron status or erythropoiesis in cord blood were assessed by linear regression and mediation analysis. RESULTS: Cord ERFE was detectable in all newborns delivered between 30 and 42 weeks of gestation, and mean concentration at birth was 0.73 ng/mL (95% CI: 0.63, 0.85 ng/mL). Cord ERFE was on average 0.25 ng/mL lower in newborns of black as opposed to white ancestry (P = 0.04). Cord ERFE was significantly associated with transferrin receptor (ß: 1.17, P < 0.001), ferritin (ß: -0.27, P < 0.01), and hemoglobin (Hb) (ß: 0.04, P < 0.05). However, cord hepcidin and the hepcidin:erythropoietin (EPO) ratio captured the most variance in newborn iron and hematologic status (>25% of variance explained). CONCLUSIONS: Neonates born to teens and women carrying multiples were able to produce ERFE in response to neonatal cord iron status and erythropoietic demand. ERFE, however, did not capture significant variance in newborn iron or Hb concentrations. In these newborns, cord hepcidin and the hepcidin:EPO ratio explained the most variance in iron status indicators at birth.

Serum Erythroferrone During Pregnancy Is Related to Erythropoietin but Does Not Predict the Risk of Anemia.

BACKGROUND: Maintaining adequate iron status during pregnancy is important for the mother and her developing fetus. Iron homeostasis is influenced by 3 regulatory hormones: erythropoietin (EPO), hepcidin, and erythroferrone (ERFE). To date, normative data on ERFE across pregnancy and its relations to other hormones and iron status indicators are limited. OBJECTIVES: The objective of this study was to characterize maternal ERFE across pregnancy and at delivery and evaluate the utility of hepcidin, ERFE, and EPO in identifying women with increased iron needs. METHODS: ERFE was measured in extant serum samples collected from 2 longitudinal cohorts composed of women carrying multiple fetuses (n = 79) and pregnant adolescents (n = 218) at midgestation (∼26 wk) and delivery (∼39 wk). Receiver operating characteristic curves were generated to characterize the predictive ability of serum ERFE, hepcidin, and EPO and their ratios to identify women at increased risk of iron deficiency and anemia. RESULTS: In these pregnant women, mean ERFE was 0.48 ng/mL at both ∼25 wk of gestation and at delivery. ERFE was positively associated with EPO at midgestation (ß = 0.14, P = 0.002, n = 202) and delivery (ß = 0.12, P < 0.001, n = 225) but was not significantly associated with maternal hepcidin at any time point surveyed. Of all hormones measured at midgestation and delivery, EPO was best able to identify women with anemia (AUC: 0.86 and 0.75, respectively) and depleted iron stores (AUC: 0.77 and 0.84), whereas the hepcidin-to-EPO ratio was best able to identify women with iron deficiency anemia (AUC: 0.85 and 0.84). CONCLUSIONS: Maternal ERFE was significantly associated with EPO but was not able to identify women with gestational iron deficiency. At term, the hepcidin-to-EPO ratio, an index that accounts for both iron status and erythropoietic demand, and EPO were the strongest indicators of maternal iron deficiency and anemia. This trial was registered at clinicaltrials.gov as NCT04517734 (https://clinicaltrials.gov/ct2/show/NCT04517734).

Early-life epilepsy after acute symptomatic neonatal seizures: A prospective multicenter study.

OBJECTIVE: We aimed to evaluate early-life epilepsy incidence, seizure types, severity, risk factors, and treatments among survivors of acute neonatal seizures. METHODS: Neonates with acute symptomatic seizures born 7/2015-3/2018 were prospectively enrolled at nine Neonatal Seizure Registry sites. One-hour EEG was recorded at age three months. Post-neonatal epilepsy and functional development (Warner Initial Developmental Evaluation of Adaptive and Functional Skills - WIDEA-FS) were assessed. Cox regression was used to assess epilepsy-free survival. RESULTS: Among 282 infants, 37 (13%) had post-neonatal epilepsy by 24-months [median age of onset 7-months (IQR 3-14)]. Among those with post-neonatal epilepsy, 13/37 (35%) had infantile spasms and 12/37 (32%) had drug-resistant epilepsy. Most children with post-neonatal epilepsy had abnormal neurodevelopment at 24-months (WIDEA-FS >2SD below normal population mean for 81% of children with epilepsy vs 27% without epilepsy, RR 7.9, 95% CI 3.6-17.3). Infants with severely abnormal neonatal EEG background patterns were more likely to develop epilepsy than those with mild/moderate abnormalities (HR 3.7, 95% CI 1.9-5.9). Neonatal EEG with ≥3 days of seizures also predicted hazard of epilepsy (HR 2.9, 95% CI 1.4-5.9). In an adjusted model, days of neonatal EEG-confirmed seizures (HR 1.4 per day, 95% CI 1.2-1.6) and abnormal discharge examination (HR 3.9, 95% CI 1.9-7.8) were independently associated with time to epilepsy onset. Abnormal (vs. normal) three-month EEG was not associated with epilepsy. SIGNIFICANCE: In this multicenter study, only 13% of infants with acute symptomatic neonatal seizures developed post-neonatal epilepsy by age 24-months. However, there was a high risk of severe neurodevelopmental impairment and drug-resistant seizures among children with post-neonatal epilepsy. Days of EEG-confirmed neonatal seizures was a potentially modifiable epilepsy risk factor. An EEG at three months was not clinically useful for predicting epilepsy. These practice changing findings have implications for family counseling, clinical follow-up planning, and future research to prevent post-neonatal epilepsy.

The impact of fluid balance on outcomes in premature neonates: a report from the AWAKEN study group.

BACKGROUND: We evaluated the epidemiology of fluid balance (FB) over the first postnatal week and its impact on outcomes in a multi-center cohort of premature neonates from the AWAKEN study. METHODS: Retrospective analysis of infants <36 weeks' gestational age from the AWAKEN study (N = 1007). FB was defined by percentage of change from birth weight. OUTCOME: Mechanical ventilation (MV) at postnatal day 7. RESULTS: One hundred and forty-nine (14.8%) were on MV at postnatal day 7. The median peak FB was 0% (IQR: -2.9, 2) and occurred on postnatal day 2 (IQR: 1,5). Multivariable models showed that the peak FB (aOR 1.14, 95% CI 1.10-1.19), lowest FB in first postnatal week (aOR 1.12, 95% CI 1.07-1.16), and FB on postnatal day 7 (aOR 1.10, 95% CI 1.06-1.13) were independently associated with MV on postnatal day 7. In a similar analysis, a negative FB at postnatal day 7 protected against the need for MV at postnatal day 7 (aOR 0.21, 95% CI 0.12-0.35). CONCLUSIONS: Positive peak FB during the first postnatal week and more positive FB on postnatal day 7 were independently associated with MV at postnatal day 7. Those with a negative FB at postnatal day 7 were less likely to require MV.

Umbilical Cord Serum Ferritin Concentration is Inversely Associated with Umbilical Cord Hemoglobin in Neonates Born to Adolescents Carrying Singletons and Women Carrying Multiples.

BACKGROUND: It has been proposed that the fetus prioritizes iron for hemoglobin production over delivery to tissues. However, few studies have evaluated the interrelations between hemoglobin and multiple iron status biomarkers in umbilical cord blood. A full understanding is needed of how these parameters influence each other within cord blood to fully interpret iron and hematologic status at birth. OBJECTIVES: We evaluated the determinants of neonatal hemoglobin and assessed the interrelations between hemoglobin, serum iron status indicators, and serum iron regulatory hormones in healthy neonates. METHODS: This was an observational study that assessed umbilical cord hemoglobin (Hb), serum ferritin (SF), erythropoietin (EPO), soluble transferrin receptor (sTfR), serum iron, hepcidin, vitamin B-12, folate, IL-6, and CRP measured in 234 neonates born to adolescents or to women carrying multiples. Correlations between these indicators were evaluated and mediation models consistent with the observed significant determinants of cord Hb concentrations were developed. RESULTS: A highly significant inverse association was found between cord SF and Hb concentrations that was not attributable to neonatal or maternal inflammation (as measured by IL-6 and CRP). The inverse association was present in the combined cohort, as well as in the adolescent and multiples cohorts independently. Mediation analyses found that EPO and hepcidin had significant indirect effects on cord Hb, associations that are explicable by mediation through SF and sTfR. CONCLUSION: In contrast to observations made in older infants, a highly significant inverse association between Hb and SF, as well positive associations between Hb and both sTfR and EPO, were observed in umbilical cord blood from neonates born to adolescents or women carrying multiples. These findings, combined with review of the published literature, indicate a need for analysis of the relations between multiple parameters to assess iron and hematologic status at birth. These clinical trials were registered at clinicaltrials.gov as NCT01582802 (https://clinicaltrials.gov/ct2/show/NCT01582802) and NCT01019902 (https://clinicaltrials.gov/ct2/show/NCT01019902).

The impact of fluid balance on outcomes in critically ill near-term/term neonates: a report from the AWAKEN study group.

BACKGROUND: In sick neonates admitted to the NICU, improper fluid balance can lead to fluid overload. We report the impact of fluid balance in the first postnatal week on outcomes in critically ill near-term/term neonates. METHODS: This analysis includes infants ≥36 weeks gestational age from the Assessment of Worldwide Acute Kidney injury Epidemiology in Neonates (AWAKEN) study (N = 645). Fluid balance: percent weight change from birthweight. PRIMARY OUTCOME: mechanical ventilation (MV) on postnatal day 7. RESULTS: The median peak fluid balance was 1.0% (IQR: -0.5, 4.6) and occurred on postnatal day 3 (IQR: 1, 5). Nine percent required MV at postnatal day 7. Multivariable models showed the peak fluid balance (aOR 1.12, 95%CI 1.08-1.17), lowest fluid balance in 1st postnatal week (aOR 1.14, 95%CI 1.07-1.22), fluid balance on postnatal day 7 (aOR 1.12, 95%CI 1.07-1.17), and negative fluid balance at postnatal day 7 (aOR 0.3, 95%CI 0.16-0.67) were independently associated with MV on postnatal day 7. CONCLUSIONS: We describe the impact of fluid balance in critically ill near-term/term neonates over the first postnatal week. Higher peak fluid balance during the first postnatal week and higher fluid balance on postnatal day 7 were independently associated with MV at postnatal day 7.

Pulmonary Hypertension Associated with Hypoxic-Ischemic Encephalopathy-Antecedent Characteristics and Comorbidities.

OBJECTIVE: To determine the characteristics of term infants with persistent pulmonary hypertension of the newborn (PPHN) associated with moderate or severe hypoxic ischemic encephalopathy (HIE). METHODS: We compared infants with and without PPHN enrolled in 2 randomized trials of therapeutic hypothermia: the induced hypothermia trial of cooling to 33.5°C for 72 hours vs normothermia, and the "usual-care" arm (33.5°C for 72 hours) of the optimizing cooling trial. RESULTS: Among 303 infants with HIE from these 2 studies, 67 (22%) had PPHN and 236 (78%) did not. We compared infants with PPHN with those without PPHN. The proportion of patients treated with therapeutic hypothermia was similar in PPHN and no-PPHN groups (66% vs 65%). Medication use during resuscitation (58% vs 44%), acidosis after birth (pH: 7.0 ± 0.2 vs 7.1 ± 0.2), severe HIE (43% vs 28%), meconium aspiration syndrome (39% vs 7%), pulmonary hemorrhage (12% vs 3%), culture-positive sepsis (12% vs 3%), systemic hypotension (65% vs 28%), inhaled nitric oxide therapy (64% vs 3%), and extracorporeal membrane oxygenation (12% vs 0%) were more common in the PPHN group. Length of stay (26 ± 21 vs 16 ± 14 days) and mortality (27% vs 16%) were higher in the PPHN group. CONCLUSIONS: PPHN is common among infants with moderate/severe HIE and is associated with severe encephalopathy, lung disease, sepsis, systemic hypotension, and increased mortality. The prevalence of PPHN was not different between those infants receiving therapeutic hypothermia at 33.5°C in these 2 trials (44/197 = 22%) compared with infants receiving normothermia in the induced hypothermia trial (23/106 = 22%).

Umbilical Cord Hepcidin Concentrations Are Positively Associated with the Variance in Iron Status among Multiple Birth Neonates.

Background: Hepcidin is a systemic regulator of iron homeostasis. Little is known about the relative role of maternal compared with cord hepcidin on neonatal iron homeostasis. Objective: This study was undertaken to evaluate inter- and intrauterine variance in neonatal iron status, vitamin B-12, folate, and inflammatory markers in a cohort of twins (n = 50), triplets (n = 14), and quadruplets (n = 1) born to 65 women. Methods: Umbilical cord blood was obtained from 144 neonates born at 34.8 ± 2.7 wk of gestation with a mean birth weight of 2236 ± 551 g (means ± SDs). Cord hemoglobin and cord serum measures of ferritin (SF), soluble transferrin receptor (sTfR), hepcidin, erythropoietin (EPO), iron, vitamin B-12, folate, interleukin 6, and C-reactive protein were evaluated. Results: Intraclass correlation coefficient (ICC) analyses were used to examine inter- and intrauterine variance in neonatal iron indicators. A greater variability in cord hepcidin (ICC = 0.39) was found between siblings. Cord hepcidin had the greatest association with cord iron indicators because cord hepcidin alone captured 63.8%, 48.4%, 44.4%, and 31.3% of the intrauterine variance in cord hemoglobin, SF, sTfR, and EPO, respectively, whereas maternal hepcidin had no effect on cord iron indicators. Significantly greater differences in cord SF (P = 0.03), sTfR (P = 0.03), hepcidin (P = 0.0003), and EPO (P = 0.03) were found between di- and trichorionic siblings than between monochorionic siblings. In contrast, cord folate (ICC = 0.79) and vitamin B-12 (ICC = 0.74) exhibited a greater variability between unrelated neonates. Conclusions: In summary, fetally derived hepcidin might have more control on intrauterine variance in iron indicators than maternal hepcidin and appears to be capable of regulating fetal iron status independently of maternal hepcidin. The use of a multiple-birth model provides a unique way to identify factors that may contribute to placental nutrient transport and iron stores at birth.

Predictors of anemia and iron status at birth in neonates born to women carrying multiple fetuses.

BACKGROUND: Iron (Fe) status of neonates born to women carrying multiple fetuses might be compromised as a consequence of the high prevalence of maternal Fe deficiency and anemia coupled with an increased risk of preterm birth. This study aimed to characterize and identify determinants of anemia in this neonatal population. METHODS: Umbilical cord blood obtained from 183 neonates was utilized to assess hemoglobin (Hb), ferritin (SF), soluble transferrin receptor (sTfR), hepcidin, serum Fe, erythropoietin, folate, vitamin B-12, C-reactive protein, and interleukin-6. Associations with maternal Fe status were explored. RESULTS: Cord Hb or SF did not change significantly as a function of gestational age at birth (25-38 wks). Neonates born to women who were obese prior to pregnancy or smoked cigarettes during pregnancy had a 4-5-fold greater odds of anemia at birth. Cord sTfR was the strongest indicator of cord Hb (P < 0.0001), and it was significantly associated with maternal sTfR at mid-gestation (P = 0.01) and delivery (P = 0.002). Cord Fe indicators were significantly associated with cord hepcidin, but not maternal hepcidin. CONCLUSION: Screening for Fe status in neonates born to women carrying multiple fetuses is warranted, especially for those born to smokers or to women who are obese at entry into pregnancy.

Umbilical Cord Coiling in High-risk Pregnancies: Associations With Determinants of Adverse Birth Outcomes and Iron Status.

Abnormal umbilical cord coiling has been associated with adverse neonatal outcomes, but the etiology of these findings remains poorly characterized. This study was undertaken to examine associations between cord coiling and maternal iron (Fe) status and to identify potential determinants of hypo- and hypercoiling in 2 higher risk obstetric groups: pregnant adolescents (≤18 years, n = 92) and adult women carrying twins (n = 49), triplets (n = 11), or quadruplets (n = 1). Umbilical cords were classified as hypo-, normo-, or hypercoiled using digital photographs to assess gross appearance. Hypocoiling and hypercoiling were observed in 44% (n = 86/195) and 13% (n = 26/195) of the combined study population. The prevalence of hypocoiling among women carrying multiples was over 3-fold higher than the prevalence in singleton pregnancies based on the published data. Within the entire study population, hypocoiling was associated with a lower gestational age at birth when compared to normocoiling and hypercoiling (36.3 ± 3.6 weeks [n = 86] vs 37.8 ± 2.7 [n = 83], P < .01, and 38.2 ± 2.6 [n = 26], P < .01, respectively), whereas hypercoiling was associated with significantly lower serum ferritin when compared to normocoiling ( P < .01) and hypocoiling ( P < .001). In the multiples cohort only, hypercoiling was significantly associated with multiparity ( P < .01) and lower birth weight ( P < .05). Further studies are needed to identify the determinants and consequences of cord coiling.

Maternal iron status during pregnancy compared with neonatal iron status better predicts placental iron transporter expression in humans.

The placenta richly expresses nonheme and heme Fe transport proteins. To address the impact of maternal and neonatal Fe status and hepcidin on the regulation of these proteins, mRNA expression and protein abundance of nonheme and heme Fe transport proteins were evaluated in placental tissue from 154 adolescents. Regression analyses found maternal Fe status was significantly associated with multiple placental nonheme and heme transporters, whereas neonatal Fe status was related to only 3 heme transporters. Across statistical analyses, maternal Fe status was consistently associated with the placental nonheme Fe importer transferrin receptor 1 (TfR1). Protein abundance of TfR1 was related to midgestation maternal serum ferritin (SF) (ß = -0.32; P = 0.005) and serum TfR (ß = 0.25; P = 0.024). Protein abundance of the heme importer, proton-coupled folate transporter, was related to neonatal SF (ß = 0.30; P = 0.016) and serum TfR (ß = -0.46; P < 0.0001). Neonatal SF was also related to mRNA expression of the heme exporter feline leukemia virus subgroup C receptor 1 (ß = -0.30; P = 0.004). In summary, maternal Fe insufficiency during pregnancy predicts increased expression of the placental nonheme Fe transporter TfR1. Associations between placental heme Fe transporters and neonatal Fe status require further study.-Best, C. M., Pressman, E. K., Cao, C., Cooper, E., Guillet, R., Yost, O. L., Galati, J., Kent, T. R., O'Brien, K. O. Maternal iron status during pregnancy compared with neonatal iron status better predicts placental iron transporter expression in humans.

Apnea after Routine Eye Examinations in Premature Infants.

Objective To determine the frequency of cardiorespiratory events following routine exams for retinopathy of prematurity (ROP). Study Design This is a retrospective review of 79 premature infants in the neonatal intensive care unit at the University of Rochester Medical Center. The baseline for each infant (mean cardiorespiratory events in the 72 hours before the exam) was compared with the number of cardiorespiratory events during the subsequent 24 hours using generalized estimating equation and the Mantel-Haenszel chi-square test to determine if there was an association between cardiorespiratory events and potential risk factors. Results Approximately 19 to 25% of infants experienced an increase in cardiorespiratory events in the 24 hours following their eye exams. These newborns were generally of a younger gestational age and lower birthweight. Conclusion The frequency of cardiorespiratory events following routine ROP exams is similar to that following routine immunizations in this population. Thus, in infants being continuously monitored during the 24 hours after the exam, alterations in medical care in the absence of other clinical signs suggestive of sepsis or clinical deterioration may not be required, limiting unnecessary antibiotic exposure, prolonged caffeine administration, unwarranted gastroesophageal reflux treatment, and undue family stress.

Effect of Therapeutic Hypothermia Initiated After 6 Hours of Age on Death or Disability Among Newborns With Hypoxic-Ischemic Encephalopathy: A Randomized Clinical Trial.

Importance: Hypothermia initiated at less than 6 hours after birth reduces death or disability for infants with hypoxic-ischemic encephalopathy at 36 weeks' or later gestation. To our knowledge, hypothermia trials have not been performed in infants presenting after 6 hours. Objective: To estimate the probability that hypothermia initiated at 6 to 24 hours after birth reduces the risk of death or disability at 18 months among infants with hypoxic-ischemic encephalopathy. Design, Setting, and Participants: A randomized clinical trial was conducted between April 2008 and June 2016 among infants at 36 weeks' or later gestation with moderate or severe hypoxic-ischemic encephalopathy enrolled at 6 to 24 hours after birth. Twenty-one US Neonatal Research Network centers participated. Bayesian analyses were prespecified given the anticipated limited sample size. Interventions: Targeted esophageal temperature was used in 168 infants. Eighty-three hypothermic infants were maintained at 33.5°C (acceptable range, 33°C-34°C) for 96 hours and then rewarmed. Eighty-five noncooled infants were maintained at 37.0°C (acceptable range, 36.5°C-37.3°C). Main Outcomes and Measures: The composite of death or disability (moderate or severe) at 18 to 22 months adjusted for level of encephalopathy and age at randomization. Results: Hypothermic and noncooled infants were term (mean [SD], 39 [2] and 39 [1] weeks' gestation, respectively), and 47 of 83 (57%) and 55 of 85 (65%) were male, respectively. Both groups were acidemic at birth, predominantly transferred to the treating center with moderate encephalopathy, and were randomized at a mean (SD) of 16 (5) and 15 (5) hours for hypothermic and noncooled groups, respectively. The primary outcome occurred in 19 of 78 hypothermic infants (24.4%) and 22 of 79 noncooled infants (27.9%) (absolute difference, 3.5%; 95% CI, -1% to 17%). Bayesian analysis using a neutral prior indicated a 76% posterior probability of reduced death or disability with hypothermia relative to the noncooled group (adjusted posterior risk ratio, 0.86; 95% credible interval, 0.58-1.29). The probability that death or disability in cooled infants was at least 1%, 2%, or 3% less than noncooled infants was 71%, 64%, and 56%, respectively. Conclusions and Relevance: Among term infants with hypoxic-ischemic encephalopathy, hypothermia initiated at 6 to 24 hours after birth compared with noncooling resulted in a 76% probability of any reduction in death or disability, and a 64% probability of at least 2% less death or disability at 18 to 22 months. Hypothermia initiated at 6 to 24 hours after birth may have benefit but there is uncertainty in its effectiveness. Trial Registration: clinicaltrials.gov Identifier: NCT00614744.

Prevalence of anemia and associations between neonatal iron status, hepcidin, and maternal iron status among neonates born to pregnant adolescents.

BACKGROUND: Little is known about anemia and iron status in US newborns because screening for anemia is typically not undertaken until 1 y of age. This study was undertaken to characterize and identify determinants of iron status in newborns born to pregnant adolescents. METHODS: Pregnant adolescents (≤ 18 y, n = 193) were followed from ≥ 12 wk gestation until delivery. Hemoglobin, ferritin, soluble transferrin receptor, serum iron, hepcidin, erythropoietin (EPO), IL-6, and C-reactive protein were assessed in maternal and cord blood. RESULTS: At birth, 21% of the neonates were anemic (Hb < 13.0 g/dl) and 25% had low iron stores (ferritin < 76 µg/l). Cord serum ferritin concentrations were not significantly associated with gestational age (GA) at birth across the range of 37-42 wk. Neonates born to mothers with ferritin < 12 µg/l had significantly lower ferritin (P = 0.003) compared to their counterparts. Hepcidin and IL-6 were significantly (P < 0.05) higher in neonates born to mothers with longer durations of active labor. CONCLUSION: Given the importance of the iron stores at birth on maintenance of iron homeostasis over early infancy, additional screening of iron status at birth is warranted among those born to this high risk obstetric population.