Racial and gender differences in the viability of extremely low birth weight infants: a population-based study

Sociodemographic Factors and Intestinal Microbiome Development in Preterm, Very Low Birth Weight Infants

OBJECTIVE

 Preterm very low birth weight (VLBW) infants are at risk for intestinal morbidities and dysbiotic development of the intestinal microbiome. Despite the influence of sociodemographic factors on premature infant health outcomes, whether they shape the intestinal microbiome early in life is not clear. The objective was to explore the associations between race, sex, and socioeconomic status and the intestinal microbiome of VLBW infants during the first 4 weeks of life.

STUDY DESIGN

 This was a secondary analysis of data from an ongoing randomized trial of 79 infants ≤30 weeks' gestation and ≤1,500 g. Stool samples were collected at week 1 through week 4, frozen to -80°C and analyzed by 16S rRNA sequencing of the V4 region using Illumina MiSeq. Reads were analyzed to measure α and β diversity as well as relative abundance of bacteria in the intestinal microbiome.

RESULTS

 Of the 79 infants, 63 had at least one sample available. Twenty-three (37%) of infants were African American, 30 (48%) were male, and 44 (71%) had Medicaid insurance. There were no statistically significant (<0.05) differences in α diversity or β diversity, and the differential abundance analysis suggests limited patterns of distinction in the intestinal microbiome between non-African American and African American infants, male and female infants, and infants with maternal private or Medicaid insurance.

CONCLUSION

 Our results suggest race, sex, and socioeconomic status shape colonization of specific microorganisms to a limited extent. Future studies should confirm these findings and determine clinical relevance through further study of differentially abundant microorganisms and additional factors contributing to colonization patterns.

KEY POINTS

· Diversity of the gut microbiome was similar between infants of varying race, sex, and socioeconomic status.. · We observed sociodemographic-linked differences in colonization of individual taxa.. · Further study is required to confirm these results and the clinical relevance of these findings..

Recognizing Our Biases, Understanding the Evidence, and Responding Equitably: Application of the Socioecological Model to Reduce Racial Disparities in the NICU

BACKGROUND

Implicit bias permeates beliefs and actions both personally and professionally and results in negative health outcomes for people of color-even in the neonatal intensive care unit (NICU). NICU clinicians may naïvely and incorrectly assume that NICU families receive unbiased care. Existing evidence establishing associations between sex, race, and neonatal outcomes may perpetuate the tendency to deny racial bias in NICU practice.

EVIDENCE ACQUISITION

Using the socioecological model as a framework, this article outlines evidence for racial health disparities in the NICU on multiple levels-societal, community, institutional, interpersonal, and individual. Using current evidence and recommendations from the National Association of Neonatal Nurses Position Statement on "Racial Bias in the NICU," appropriate interventions and equitable responses of the NICU clinician are explored.

RESULTS

Based on current evidence, clinicians should reject the notion that the social construct of race is the root cause for certain neonatal morbidities. Instead, clinicians should focus on the confluence of medical and social factors contributing to each individual infant's progress. This critical distinction is not only important for clinicians employing life-saving interventions, but also for those who provide routine care, developmental care, and family education-as these biases can and do shape clinical interactions.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Healthcare practitioners have an ethical and moral responsibility to maintain up-to-date knowledge of new evidence that impacts our clinical practice. The evidence demonstrates the importance of recognizing the enduring role of racism in the health and well-being of people of color and the need to adjust care accordingly.

Racial disparities in the development of comorbid conditions after preterm birth: A narrative review

Despite recognition and attempts to reduce racial disparities in perinatal outcomes, Black infants are still disproportionately represented among those who are born preterm. Postnatal investigations of racial disparities in comorbidities and outcomes after preterm birth are increasing, although their results and interpretations are conflicting. In the present review, we 1.) identify important methodological limitations of that literature 2.) summarize the conflicting literature investigating racial disparities, specifically Black-white differences, in postnatal comorbidities and outcomes after preterm birth 3.) describe mechanisms by which racism operates to contextualize our understanding to inform future work to actively reduce disparities in preterm birth and subsequently, its complications.

Exploring Social and Demographic Factors as Determinants of Intestinal Inflammation in Very Low Birth-Weight Infants

BACKGROUND

Very low birth-weight (VLBW) infants are disproportionately affected by inflammatory morbidities including necrotizing enterocolitis. Despite the influence of social and demographic factors on infant health outcomes, their relationship with intestinal inflammation is unknown.

PURPOSE

To explore the influence of maternal race, maternal socioeconomic status, and infant sex on intestinal inflammation in VLBW infants.

METHODS

This was a secondary analysis of existing data from a randomized controlled trial of 143 infants 32 weeks' gestation or less and weighing 1250 g or less. In the previous study, fecal calprotectin and S100A12 values were collected at weeks 3 and 6. The infant sample was determined on the basis of the availability of these results, which served as intestinal inflammation biomarkers for the present study. General linear mixed models assessed the relationship between biomarkers and social and demographic factors. Gestational age, antibiotic exposure, mother's own milk feeding, acuity, and week of sample collection were used as control variables.

FINDINGS/RESULTS

The sample included 124 infants. Fifty-two infants (42%) were African American, 86 (69%) had Medicaid coverage, and 65 (53%) were male. Fecal calprotectin levels were higher in African American infants (P = .02) and infants with private insurance coverage (P = .009); no difference was found between sexes. There was no association between S100A12 levels and infant sex, maternal race, or socioeconomic status.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Consideration of social and demographic factors may be important when caring for VLBW infants. Further exploration of factors contributing to associations between social or demographic factors and intestinal inflammation is needed.

Race and neonatal respiratory morbidity in the late preterm period

BACKGROUND

Prematurity is one of the leading causes of perinatal morbidity and mortality. Some studies suggest that respiratory disease may differ by race in early preterm infants. However, the role of race in late preterm neonatal morbidity is not yet established.

OBJECTIVE

The objective of our study was to determine whether neonatal respiratory morbidity differs by race in neonates born late preterm.

STUDY DESIGN

This was a secondary analysis of a randomized trial of women at high risk for late preterm delivery (Antenatal Late Preterm Steroids). Our study was limited to women with nonanomalous, singleton gestations, delivering between 34+0 to 36+6 weeks. Women were categorized into 4 groups by race: Black, White, Asian, or other/mixed. The primary outcome was a neonatal composite of treatment in the first 72 hours (continuous positive airway pressure or high-flow nasal cannula >2 hours, oxygen >4 hours, extracorporeal membrane oxygenation or mechanical ventilation) or stillbirth or neonatal death before 72 hours. The secondary outcomes included severe respiratory morbidity (the primary outcome extending continuous positive airway pressure or high-flow nasal cannula to >12 continuous hours and oxygen to at least 24 continuous hours), respiratory distress syndrome, transient tachypnea of the newborn, apnea, neonatal intensive care unit admission, bronchopulmonary dysplasia, and surfactant administration. The primary and secondary outcomes were assessed in the active (steroid) and placebo groups separately. We fit a logistic regression model to adjust for confounders related to respiratory morbidity.

RESULTS

Of a total of 2331 included women, 26.9% (n=627) were Black/African American, 57.1% (n=1333) White, 3.56% (n=83) Asian, and 12.36% (n=288) were other/mixed. In the placebo group, the rate of the primary outcome was significantly higher in Whites (18.6%) and Asians (22.8%) compared with the African American/Black group (12.3%) (P=.03). Adjusting for confounders, the primary outcome was not significant between the groups. The primary predictor for respiratory morbidity was a prior pregnancy with neonatal respiratory morbidity. Findings were similar in the steroid group, but severe respiratory morbidity was less common in Black infants compared with White infants (adjusted odds ratio, 0.45; 95% confidence interval, 0.24-0.83). However, a prior pregnancy with neonatal respiratory complications was no longer associated with respiratory morbidity after receipt of betamethasone.

CONCLUSION

Late preterm respiratory morbidity was similar between racial groups. Although a history of pregnancy with previous neonatal respiratory disease is the strongest risk factor for recurrence, this risk factor is mitigated by the receipt of steroids.

Prediction of short-term neonatal complications in preterm infants using exome-wide genetic variation and gestational age: a pilot study

BACKGROUND

Preterm birth is the leading cause of mortality and morbidity in young children, with over a million deaths per year worldwide arising from neonatal complications (NCs). NCs are moderately heritable although the genetic causes are largely unknown. Therefore, we investigated the impact of accumulated genetic variation (burden) on NCs in non-Hispanic White (NHW) and non-Hispanic Black (NHB) preterm infants.

METHODS

We sequenced 182 exomes from infants with gestational ages from 26 to 31 weeks. These infants were cared for in the same time period and hospital environment. Eighty-one preterm infants did not develop NCs, whereas 101 developed at least one severe complication. We measured the effect of burden at the single-gene and exome-wide levels and derived a polygenic risk score (PRS) from the top 10 genes to predict NCs.

RESULTS

Burden across the exome was associated with NCs in NHW (p = 0.05) preterm infants suggesting that multiple genes influence susceptibility. In a post hoc analysis, we find that PRS alone predicts NCs (AUC = 0.67) and that PRS is uncorrelated with GA ([Formula: see text] = 0.05; p = 0.53). When PRS and GA at birth are combined, the AUC is 0.87.

CONCLUSIONS

Our results support the hypothesis that genetic burden influences NCs in NHW preterm infants.

Prematurity and race account for much of the interstate variation in infant mortality rates in the United States

OBJECTIVE

To assess the correlation between infant mortality and extreme prematurity by state.

STUDY DESIGN

This ecological study included data on 28,526,534 infants from 2007 to 2013 in all 50 US states and DC using CDC WONDER linked birth and infant death records. Regression analyses determined the correlation between infant and neonatal mortality rates and the proportion of extremely preterm, extremely low birth weight, and black births by state.

RESULTS

State infant and neonatal mortality rates were directly and highly correlated with the proportion of extremely preterm births (infant, r² = 0.71, P < 0.001; neonatal, r² = 0.77, P < 0.001) and extremely low birth weight births (r² = 0.63, P < 0.001; r² = 0.73, P < 0.001). The proportion of black births also correlated directly with infant and neonatal mortality rates.

CONCLUSIONS

Interstate variation in infant and neonatal mortality rates are primarily driven by rates of extremely preterm and extremely low birth weight births which is closely related to the proportion of black births.

Trends in sex-specific differences in outcomes in extreme preterms: progress or natural barriers?

OBJECTIVE

To examine the differences and trends of outcomes of preterm boys and girls born at <29 weeks' gestation.

DESIGN

A retrospective cohort study.

SETTING

Data collected by the Canadian Neonatal Network.

PATIENTS

Neonates born at <29 weeks' gestation between January 2007 and December 2016.

MAIN OUTCOME MEASURES

We examined rate differences in mortality, major morbidities (bronchopulmonary dysplasia, severe brain injury, retinopathy of prematurity, necrotising enterocolitis and late-onset sepsis) and care practices (antenatal steroids, magnesium sulfate, maternal antibiotics, ventilation and surfactant administration) between boys and girls and evaluated trends in these rate differences over the study period. Our primary outcome was a composite of mortality and any one of the five morbidities.

RESULTS

Our study included 8219 boys and 6934 girls with median gestational age of 26 (IQR 25-28) weeks. The composite of death or major morbidity was more common in boys (adjusted risk ratio 1.07, 95% CI 1.05 to 1.10) and remained higher in boys over the study period. The gap between boys and girls for mortality, however, decreased over time: the slope for boys was -0.043 (95% CI -0.071 to -0.015) and for girls was -0.012 (95% CI -0.045 to 0.020) (p=0.04). All other morbidities remained higher in boys. Care practices changed at similar rates between the sexes.

CONCLUSION

The difference between the mortality rates for boys and girls decreased over the study period but the difference between rates of the major morbidities was unchanged. More research is needed to understand biological differences and outcome disparities.

Magnesium sulfate and sex differences in cardiovascular and neural adaptations during normoxia and asphyxia in preterm fetal sheep

Magnesium sulfate (MgSO₄) is recommended for preterm neuroprotection, preeclampsia, and preterm labor prophylaxis. There is an important, unmet need to carefully test clinical interventions in both sexes. Therefore, we aimed to investigate cardiovascular and neurophysiological adaptations to MgSO₄ during normoxia and asphyxia in preterm male and female fetal sheep. Fetuses were instrumented at 98 ± 1 days of gestation (term = 147 days). At 104 days, unanesthetized fetuses were randomly assigned to intravenous MgSO₄ ( n = 12 female, 10 male) or saline ( n = 13 female, 10 male). At 105 days fetuses underwent umbilical cord occlusion for up to 25 min. Occlusions were stopped early if mean arterial blood pressure (MAP) fell below 8 mmHg or asystole occurred for >20 s. During normoxia, MgSO₄ was associated with similar reductions in fetal heart rate (FHR), EEG power, and movement in both sexes ( P < 0.05 vs. saline controls) and suppression of α- and β-spectral band power in males ( P < 0.05 vs. saline controls). During occlusion, similar FHR and MAP responses occurred in MgSO₄-treated males and females compared with saline controls. Recovery of FHR and MAP after release of occlusion was more prolonged in MgSO₄-treated males ( P < 0.05 vs. saline controls). During and after occlusion, EEG power was lower in MgSO₄-treated females ( P < 0.05 vs. saline controls). In conclusion, MgSO₄ infusion was associated with subtle sex-specific effects on EEG spectral power and cardiac responses to asphyxia in utero, possibly reflecting sex-specific differences in interneuronal connectivity and regulation of cardiac output.

Levels and determinants of low birth weight in infants delivered under the national health insurance scheme in Northern Ghana

This research determined the levels and odds ratios for low birth weight (LBW) infants delivered under the National Health Insurance Scheme (NHIS) compared to LBW infants delivered under the previous "Cash and Carry" system in Northern Ghana. Birth records of infants delivered before and after implementation of the NHIS in Northern Ghana were examined. Records of each day's births during the identified periods were abstracted. Days with fewer or no births were accommodated by oversampling from days before or after. Chi squared tests of independence were used to examine the bivariate association between categorical independent variables and LBW. Multiple logistic regression models were used to examine the relationships among selected variables for mothers and infants and the odds ratios for LBW. Infants delivered under NHIS had lower rates of LBW (16.8 %) compared to infants born under Cash and Carry (23.3 %). Mothers who delivered under NHIS were significantly less likely to have infants at LBW (unadjusted OR 0.65; 95 % CI 0.49, 0.86). The rate of LBW among infants delivered under NHIS is significantly lower than among infants delivered under Cash and Carry. The rate of LBW under Cash and Carry in 2000 fell by 27 % in relation to the NHIS in 2010. These findings confirm that the NHIS, which gives pregnant women in Northern Ghana four antenatal visits and access to skilled health professionals for delivery at no cost to the mother, significantly improved birth weight outcomes.

A moving line in the sand: a review of obstetric management surrounding periviability

Periviable birth poses numerous clinical and ethical challenges for the practicing clinician. We review the data surrounding the administration of corticosteroids for fetal lung maturity, antibiotics in the case of preterm premature rupture of membranes, magnesium sulfate for cerebral palsy prophylaxis, fetal monitoring, and cesarean delivery. The ethical complexities of patient counseling are also reviewed with a recommendation toward shared decision making between patient and physician.

Periviable birth: executive summary of a Joint Workshop by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists

This is an executive summary of a workshop on the management and counseling issues of women anticipated to deliver at a periviable gestation (broadly defined as 20 0/7 through 25 6/7 weeks of gestation), and the treatment options for the newborn. Upon review of the available literature, the workshop panel noted that the rates of neonatal survival and neurodevelopmental disabilities among the survivors vary greatly across the periviable gestations and are significantly influenced by the obstetric and neonatal management practices (for example, antenatal steroid, tocolytic agents and antibiotic administration; cesarean birth; and local protocols for perinatal care, neonatal resuscitation and intensive care support). These are, in turn, influenced by the variations in local and regional definitions of limits of viability. Because of the complexities in making difficult management decisions, obstetric and neonatal teams should confer prior to meeting with the family, when feasible. Family counseling should be coordinated with the goal of creating mutual trust, respect and understanding, and should incorporate evidence-based counseling methods. Since clinical circumstances can change rapidly with increasing gestational age, counseling should include discussion of the benefits and risks of various maternal and neonatal interventions at the time of counseling. There should be a plan for follow-up counseling as clinical circumstances evolve. The panel proposed a research agenda and recommended developing educational curricula on the care and counseling of families facing the birth of a periviable infant.

Periviable birth: executive summary of a joint workshop by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists

This is an executive summary of a workshop on the management and counseling issues of women anticipated to deliver at a periviable gestation (broadly defined as 20 0/7 through 25 6/7 weeks of gestation) and the treatment options for the newborn infant. Upon review of the available literature, the workshop panel noted that the rates of neonatal survival and neurodevelopmental disabilities among the survivors vary greatly across the periviable gestations and are significantly influenced by the obstetric and neonatal management practices (eg, antenatal steroid, tocolytic agents, and antibiotic administration; cesarean birth; and local protocols for perinatal care, neonatal resuscitation, and intensive care support). These are, in turn, influenced by the variations in local and regional definitions of limits of viability. Because of the complexities in making difficult management decisions, obstetric and neonatal teams should confer prior to meeting with the family, when feasible. Family counseling should be coordinated with the goal of creating mutual trust, respect, and understanding and should incorporate evidence-based counseling methods. Since clinical circumstances can change rapidly with increasing gestational age, counseling should include discussion of the benefits and risks of various maternal and neonatal interventions at the time of counseling. There should be a plan for follow-up counseling as clinical circumstances evolve. The panel proposed a research agenda and recommended developing educational curricula on the care and counseling of families facing the birth of a periviable infant.

Uteroplacental adenovirus vascular endothelial growth factor gene therapy increases fetal growth velocity in growth-restricted sheep pregnancies

Fetal growth restriction (FGR) occurs in ∼8% of pregnancies and is a major cause of perinatal mortality and morbidity. There is no effective treatment. FGR is characterized by reduced uterine blood flow (UBF). In normal sheep pregnancies, local uterine artery (UtA) adenovirus (Ad)-mediated overexpression of vascular endothelial growth factor (VEGF) increases UBF. Herein we evaluated Ad.VEGF therapy in the overnourished adolescent ewe, an experimental paradigm in which reduced UBF from midgestation correlates with reduced lamb birthweight near term. Singleton pregnancies were established using embryo transfer in adolescent ewes subsequently offered a high intake (n=45) or control intake (n=12) of a complete diet to generate FGR or normal fetoplacental growth, respectively. High-intake ewes were randomized midgestation to receive bilateral UtA injections of 5×10¹¹ particles Ad.VEGF-A165 (n=18), control vector Ad.LacZ (n=14), or control saline (n=13). Fetal growth/well-being were evaluated using serial ultrasound. UBF was monitored using indwelling flowprobes until necropsy at 0.9 gestation. Vasorelaxation, neovascularization within the perivascular adventitia, and placental mRNA expression of angiogenic factors/receptors were examined using organ bath analysis, anti-vWF immunohistochemistry, and qRT-PCR, respectively. Ad.VEGF significantly increased ultrasonographic fetal growth velocity at 3-4 weeks postinjection (p=0.016-0.047). At 0.9 gestation fewer fetuses were markedly growth-restricted (birthweight >2SD below contemporaneous control-intake mean) after Ad.VEGF therapy. There was also evidence of mitigated fetal brain sparing (lower biparietal diameter-to-abdominal circumference and brain-to-liver weight ratios). No effects were observed on UBF or neovascularization; however, Ad.VEGF-transduced vessels demonstrated strikingly enhanced vasorelaxation. Placental efficiency (fetal-to-placental weight ratio) and FLT1/KDR mRNA expression were increased in the maternal but not fetal placental compartments, suggesting downstream effects on placental function. Ad.VEGF gene therapy improves fetal growth in a sheep model of FGR, although the precise mechanism of action remains unclear.

Risk Factors for Invasive Fungal Infection in Premature Infants: Enhancing a Targeted Prevention Approach

BACKGROUND

Premature infants are at high risk of developing invasive candidal infections (ICI). We investigated maternal and perinatal risk factors for ICI that may help in defining at-risk infants, allowing more targeted antifungal prophylaxis to prevent morbidity and mortality.

METHODS

Maternal and neonatal data from infants with a birthweight between 500 and 1250 g admitted across 95 neonatal intenisve care units were analyzed for risk factors for ICI.

RESULTS

Data from 1890 infants were analyzed, 78 of whom had ICI. Overall mortality was 20.5% for all cases of ICI, 18.8% with candidemia, 17.2% with candiduria, and 75% when Candida was isolated in both the blood and urine. Birthweight, gestational age, male sex, and vaginal delivery were predictors of infection on univariate analysis. After logistic regression, gestational age (P < .01) and male sex (P < .01) remained significant. Vaginal birth and receiving antibiotics during the first week of life increased the risk for ICI in the 22-25 weeks' and 26-28 weeks' gestation subgroups.

CONCLUSIONS

Gestational age and male gender are risk factors for the development of ICI, whereas vaginal delivery and antibiotics during the first week further increase the incidence in the more premature infants. Knowing maternal and perinatal risk factors for ICI allows more targeted antifungal prophylaxis in at-risk infants.

A new framework to evaluate the quality of a neonatal death

Management of the infant in the neonatal intensive care unit (NICU) focuses on stabilization and survival but sometimes death is an inevitable outcome. Dying neonates deserve a good death. It is unknown whether we are providing neonates with a good death. This article introduces a framework describing components needed for a good death in the NICU. Initially based on an adult model, this new framework incorporates appropriate components of Emanuel and Emanuel's framework ( 1998 ) and puts them into a context applicable to neonates. The proposed concepts and relationships will require future testing and revision as indicated by the evidence.

Survival of pre-viable preterm infants in the United States: a systematic review and meta-analysis

The objective of this paper is to review observational studies that addressed the survival of pre-viable gestations in the United States. We searched PubMed, Ovid, CINAHL, and Web of Knowledge for studies reporting survival of infants born at <24 gestational weeks and/or <500g in the United States and published between January 2003 and January 2013. The full texts of 70 articles were examined and a total of 15 studies qualified and were selected. We analyzed fixed-effect and random-effects models for eight studies on survival to discharge. Pooled survival to discharge in the random-effects model was 45.9% (95% CI: 41.1-51.7) and 39.7% in the fixed-effect model (95% CI: 38.8-40.7). Studies differed by pre-viable survival measures and epochs (1985-2009). Protective factors included antenatal corticosteroids, neonatal resuscitation, and intensive care. The current survival threshold for pre-viable infants warrants reconsideration of the limits of viability. Protective factors that enhance survival should be considered in the management of these infants.

The attitudes of neonatal professionals towards end-of-life decision-making for dying infants in Taiwan

The purposes of research were to describe the neonatal clinicians' personal views and attitudes on neonatal ethical decision-making, to identify factors that might affect these attitudes and to compare the attitudes between neonatal physicians and neonatal nurses in Taiwan. Research was a cross-sectional design and a questionnaire was used to reach different research purposes. A convenient sample was used to recruit 24 physicians and 80 neonatal nurses from four neonatal intensive care units in Taiwan. Most participants agreed with suggesting a do not resuscitate (DNR) order to parents for dying neonates (86.5%). However, the majority agreed with talking to patients about DNR orders is difficult (76.9%). Most participants agree that review by the clinical ethics committee is needed before the recommendation of 'DNR' to parents (94.23%) and nurses were significantly more likely than physicians to agree to this (p=0.043). During the end-of-life care, most clinicians accepted to continue current treatment without adding others (70%) and withholding of emergency treatments (75%); however, active euthanasia, the administration of drug to end-of-life, was not considered acceptable by both physicians and nurses in this research (96%). Based on our research results, providing continuing educational training and a formal consulting service in moral courage for neonatal clinicians are needed. In Taiwan, neonatal physicians and nurses hold similar values and attitudes towards end-of-life decisions for neonates. In order to improve the clinicians' communication skills with parents about DNR options and to change clinicians' attitudes for providing enough pain-relief medicine to dying neonates, providing continuing educational training and a formal consulting service in moral courage are needed.

Intrauterine growth standards: a cross-sectional study in a population of nigerian newborns

The aim of the study was to define an intrauterine growth curve for a population of Nigerian newborn babies. A cross-sectional observational study design was adopted. Weight, length and head circumference were all measured in consecutive singleton deliveries at the University of Ilorin Teaching Hospital over a 3-year period. Gestational age (GA) of the babies was estimated from the last menstrual period or first trimester ultrasound. The estimates obtained were clinically validated using the Ballard score. Mean birth weights and percentiles of the weight, length and head circumferences for the respective GA were estimated using the SPSS 15 software package. A total of 5273 babies were recruited for the study with GA ranging from 25-44 weeks. Comparison of the mean birth weights of the various GA with the data from Denver, Colorado, showed that Nigerian babes tended to weigh less at the early GA, although these differences were not statistically significant. Between 26-36 weeks, the average weights of both sexes were similar; however, beyond this time point there was a consistent increase in the average weight of the males over the female babies. Growth curves for Nigerian newborn babies were generated and showed that the mean birth weight of Nigerian preterm babies was lighter than that of babies in Colorado. The impact of these differences on the classification of newborns will require further evaluation.

Evaluating the effect of hospital and insurance type on the risk of 1-year mortality of very low birth weight infants: controlling for selection bias

OBJECTIVES

We examined the effect of hospital type and medical coverage on the risk of 1-year mortality of very low birth weight (VLBW) infants while adjusting for possible selection bias.

METHODS

The study population was limited to singleton live birth infants having birth weight between 500 and 1500 g with no congenital anomalies who were born in Arkansas hospitals between 2001 and 2007. Propensity score (PS) matching and PS covariate adjustment were used to mitigate selection bias. In addition, a conventional multivariable logistic regression model was used for comparison purposes.

RESULTS

Generally, all 3 analytical approaches provided consistent results in terms of the estimated relative risk, absolute risk reduction, and the number needed to treat. Using the PS matching method, VLBW infants delivered at a hospital with a neonatal intensive care unit (NICU) were associated with a 35% relative decrease (95% bootstrap confidence interval, 18.5%-48.9%) in the risk of 1-year mortality as compared with those infants delivered at non-NICU hospitals. Furthermore, our results showed that on average, 16 VLBW infants (95% bootstrap confidence interval, 11-32), would need to be delivered at a hospital with an NICU to prevent 1 additional death at 1 year. However, there was not a difference in the risk of 1-year mortality between VLBW infants born to Medicaid-insured versus non-Medicaid-insured women.

CONCLUSIONS

Estimated relative risk of infant mortality was significantly lower for births that occurred in hospitals with an NICU; therefore, greater efforts should be made to deliver VLBW neonates in an NICU hospital.

Effect of antenatal zinc supplementation on impetigo in infants in Bangladesh

We sought to determine the effects of maternal zinc supplementation on skin infections among infants in poor urban areas of Dhaka, Bangladesh. A double-blind, placebo-controlled, randomized trial was conducted among 199 and 221 Bangladeshi infants whose mothers were administered 30 mg daily of zinc or placebo, respectively. The mothers received zinc supplementation from 12-16 weeks' gestation until delivery, and the infants were followed up until 6 months of age. Among the infants of mothers who received zinc supplementation during the antenatal period, 10.6% had at least 1 episode of impetigo compared with 19.6% of the infants of mothers in the placebo group (P = 0.01). Infants in the treatment group had a 54% reduction in incidence rate of episodes of impetigo when compared with infants in the placebo group (P = 0.01). The effect of zinc supplementation was more pronounced among male infants (64% reduction) and intrauterine growth restricted and low birth weight infants (73% reduction) and among infants of mothers with increased parity (60% reduction) or decreased socioeconomic status (71% reduction).

A cross-sectional study of glucose regulation in young adults with very low birth weight: impact of male gender on hyperglycaemia

OBJECTIVES

To investigate glucose regulation in young adults with very low birth weight (VLBW; <1500 g) in an Asian population.

DESIGN

Cross-sectional observational study.

SETTING

A general hospital in Hamamatsu, Japan.

PARTICIPANTS

111 young adults (42 men and 69 women; aged 19-30 years) born with VLBW between 1980 and 1990. Participants underwent standard 75 g oral glucose tolerance test (OGTT).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcomes were glucose and insulin levels during OGTT and risk factors for a category of hyperglycaemia defined as follows: diabetes mellitus, impaired glucose tolerance (IGT), impaired fasting glycaemia (IFG) and non-diabetes/IGT/IFG with elevated 1 h glucose levels (>8.6 mmol/l). The secondary outcomes were the pancreatic β cell function (insulinogenic index and homeostasis model of assessment for beta cell (HOMA-β)) and insulin resistance (homeostasis model of assessment for insulin resistance (HOMA-IR)).

RESULTS

Of 111 young adults with VLBW, 21 subjects (19%) had hyperglycaemia: one had type 2 diabetes, six had IGT, one had IFG and 13 had non-diabetes/IGT/IFG with elevated 1 h glucose levels. In logistic regression analysis, male gender was an independent risk factor associated with hyperglycaemia (OR 3.34, 95% CI 1.08 to 10.3, p=0.036). Male subjects had significantly higher levels of glucose and lower levels of insulin during OGTT than female subjects (p<0.001 for glucose and p=0.005 for insulin by repeated measures analysis of variance). Pancreatic β cell function was lower in men (insulinogenic index: p=0.002; HOMA-β: p=0.001), although no gender difference was found in insulin resistance (HOMA-IR: p=0.477). In male subjects, logistic regression analysis showed that small for gestational age was an independent risk factor associated with hyperglycaemia (OR 33.3, 95% CI 1.67 to 662.6, p=0.022).

CONCLUSIONS

19% of individuals with VLBW already had hyperglycaemia in young adulthood, and male gender was a significant independent risk factor of hyperglycaemia. In male young adults with VLBW, small for gestational age was associated with hyperglycaemia.

Infant autonomic functioning and neonatal abstinence syndrome

BACKGROUND

Neonatal abstinence syndrome (NAS) expression is widely variable among affected infants and the reasons for this variability are largely unknown; mechanisms that predispose infants to NAS expression are not understood. It has been postulated that the regulatory problems of prenatally drug exposed infants are manifested in dysfunctional vagal regulation of autonomic processes. The current study examines whether cardiac vagal tone, an indicator of parasympathetic neuroregulation, provides a marker for autonomic dysregulation subsequently expressed as NAS in prenatally opioid-exposed newborns.

METHODS

Heart period (HP) and cardiac vagal tone (V) were derived from electrocardiogram data collected from 64 methadone-exposed infants on postnatal days 1 and 3. The postpartum NAS course was assessed serially.

RESULTS

Infants with lower V on day 1 had significantly higher NAS symptomatology on day 3. Boys had more severe NAS symptoms than girls through the first 4 days of life and, among infants receiving pharmacologic treatment for NAS, boys required longer treatment course and hospitalizations. Greater poly-drug exposure, detected through toxicology screening throughout pregnancy, and cocaine use in particular, were associated with lower V and shorter HP (faster heart rate) in newborns. Multiple regression models accounted for 25-35% of the variance in NAS symptoms and duration of hospitalization in methadone-exposed infants. Significant predictors included infant sex, SSRI/SNRI use, and cigarette smoking.

CONCLUSIONS

Results support the hypothesis of a biologic vulnerability of autonomic regulatory functioning in methadone-exposed infants and greater male infant vulnerability to maternal methadone use.

A longitudinal description of heart rate variability in 28--34-week-old preterm infants

The purpose of this study was to longitudinally describe changes in heart rate variability (HRV) from 28 to 34 weeks postmenstrual age (PMA). A convenience sample of 31 low-risk preterm infants participated. HRV was quantified using a spectral analysis of heart periods and recorded during seven weekly test sessions from an electrocardiogram (ECG) signal. The total range of frequency components (0.04-2.0 Hz), high-frequency (HF) components (0.30-1.3 Hz), and ratio of low-to-high frequency (LF/HF) components (0.04-0.20/ 0.30-1.3 Hz) were measured. A mixed general linear model analysis revealed no significant change over weekly test sessions for the total, the high, and the ratio of LF/HF components. A significant interaction effect was, however, noted in the HF components for test session x gender (df = 1; F = 4.85; p = .030). With increasing age, the HF components for females increased or displayed a pattern of HRV indicative of a more mature autonomic nervous system (ANS). Study findings warrant further investigation of the impact of gender on normative descriptions of HRV.

The relationship between birth weight, gestational age and perfluorooctanoic acid (PFOA)-contaminated public drinking water

BACKGROUND

Recent studies have examined the associations between perfluorooctanoic acid (PFOA) levels in cord blood and maternal plasma with lowered birth weight and gestational age in humans; however, no study has examined these effects in a population of known high PFOA exposure. Residents drinking PFOA-contaminated water from the Little Hocking Water Association (LHWA) in Washington County, Ohio have serum PFOA levels approximately 80 times those in the general U.S. population.

OBJECTIVES

To compare birth weights and gestational ages of neonates born to mothers residing in zip codes with water service provided completely, partially or not at all by the LHWA.

METHODS

Multiple logistic and linear regression analyses were performed on singleton neonatal birth weight data supplied by the Ohio Department of Health to examine the associations between LHWA water service category (used as a surrogate for PFOA exposure) with mean birth weight, mean gestational age, the likelihood of low birth weight (<2500 g), and the likelihood of preterm birth (<37 completed weeks of gestation). All models were adjusted for maternal age, gestational age, sex, race and population-level socioeconomic status.

RESULTS

The incidence of low birth weight, preterm birth, mean birth weight and mean gestational age of neonates did not significantly differ among water service categories.

CONCLUSION

Markedly elevated PFOA exposure, as categorized by water service category, is not associated with increased risk of lowered birth weight or gestational age. This study does not confirm earlier findings of an association between PFOA and lowered birth weight observed at normal population levels.

Personal assistance for children and adolescents (0-18) with both physical and intellectual impairments

BACKGROUND

There is a high and increasing prevalence of impairments among children and adolescents in the West. Many countries offer personal assistance in the form of individualised support for people living in the community by a paid assistant other than a healthcare professional for at least 20 hours per week.

OBJECTIVES

To assess the effectiveness of personal assistance for children and adolescents with both physical and intellectual impairments, and the impacts of personal assistance on others, compared to other interventions.

SEARCH STRATEGY

Electronic databases including CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, ERIC, Dissertation Abstracts International and a variety of specialist Swedish databases were searched from 1980 to June 2005; reference lists were checked; 345 experts, organisations, government bodies and charities were contacted in an attempt to locate relevant research.

SELECTION CRITERIA

Children and adolescents with both physical and intellectual impairments (0-18 years) living in the community who require assistance to perform tasks of daily living (e.g., bathing and eating) and participate in normal activities due to permanent impairments. Controlled studies of personal assistance in which participants were prospectively assigned to study groups and in which control group outcomes were measured concurrently with intervention group outcomes were included.

DATA COLLECTION AND ANALYSIS

Titles and abstracts were examined by two reviewers. 130 full papers were examined. None met the inclusion criteria.

MAIN RESULTS

No eligible studies were found.

AUTHORS' CONCLUSIONS

Research in this field is limited, though one related review provides some evidence of the effectiveness of personal assistance for children and adolescents with intellectual impairments. When implementing new programmes, recipients could be randomly assigned to different forms of assistance. While advocates may support personal assistance for myriad reasons, this review demonstrates that further studies are required to determine which models of personal assistance are most effective and efficient for particular people.

Personal assistance for children and adolescents (0-18) with intellectual impairments

BACKGROUND

There is a high and increasing prevalence of intellectual impairments among children and adolescents in the West. Many countries offer personal assistance in the form of individualised support for people living in the community by a paid assistant other than a healthcare professional for at least 20 hours per week.

OBJECTIVES

To assess the effectiveness of personal assistance for children and adolescents with intellectual impairments, and the impacts of personal assistance on others, compared to other interventions.

SEARCH STRATEGY

Electronic databases including CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, ERIC, Dissertation Abstracts International and a variety of specialist Swedish databases were searched from 1980 to June 2005; reference lists were checked; 345 experts, organisations, government bodies and charities were contacted in an attempt to locate relevant research.

SELECTION CRITERIA

Children and adolescents with intellectual impairments (0-18 years) living in the community who require assistance to perform tasks of daily living (e.g., bathing and eating) and participate in normal activities due to permanent impairments. Controlled studies of personal assistance in which participants were prospectively assigned to study groups and in which control group outcomes were measured concurrently with intervention group outcomes were included.

DATA COLLECTION AND ANALYSIS

Titles and abstracts were examined by two reviewers. Outcome data were extracted. Studies were assessed for the possibility of bias. Results and potential sources of bias are presented for included studies.

MAIN RESULTS

One included study randomised 1002 participants to personal assistance or usual care. Whilst personal assistance was generally preferred over other services, some people prefer other models of care. This review indicates that personal assistance may have some benefits for some recipients and may benefit caregivers. However, near complete dependence on proxy respondents raises concerns about the validity of these results. Paid assistance probably substitutes for informal care and may cost government more than alternatives; however, the total costs to recipients and society are currently unknown.

AUTHORS' CONCLUSIONS

Research in this field is limited. When implementing new programmes, recipients could be randomly assigned to different forms of assistance. While advocates may support personal assistance for myriad reasons, this review demonstrates that further studies are required to determine which models of personal assistance are most effective and efficient for particular people.

Personal assistance for children and adolescents (0-18) with physical impairments

BACKGROUND

There is a high and increasing prevalence of impairments among children and adolescents in the West. Many countries offer personal assistance in the form of individualised support for people living in the community by a paid assistant other than a healthcare professional for at least 20 hours per week.

OBJECTIVES

To assess the effectiveness of personal assistance for children and adolescents with physical impairments, and the impacts of personal assistance on others, compared to other interventions.

SEARCH STRATEGY

Electronic databases including CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, ERIC, Dissertation Abstracts International and a variety of specialist Swedish databases were searched from 1980 to June 2005; reference lists were checked; 345 experts, organisations, government bodies and charities were contacted in an attempt to locate relevant research.

SELECTION CRITERIA

Children and adolescents with physical impairments (0-18 years) living in the community who require assistance to perform tasks of daily living (e.g., bathing and eating) and participate in normal activities due to permanent impairments. Controlled studies of personal assistance in which participants were prospectively assigned to study groups and in which control group outcomes were measured concurrently with intervention group outcomes were included.

DATA COLLECTION AND ANALYSIS

Titles and abstracts were examined by two reviewers. 130 full papers were examined. None met the inclusion criteria.

MAIN RESULTS

No eligible studies were found.

AUTHORS' CONCLUSIONS

Research in this field is limited. When implementing new programmes, recipients could be randomly assigned to different forms of assistance. While advocates may support personal assistance for myriad reasons, this review demonstrates that further studies are required to determine which models of personal assistance are most effective and efficient for particular people.

Risk factors for pneumothorax in very low birth weight infants

OBJECTIVES

To identify risk factors for pneumothorax in very low birth weight infants.

DESIGN

Retrospective case-control study.

SETTING

Neonatal intensive care unit in a pediatric tertiary care center.

PATIENTS

Very low birth weight infants.

INTERVENTIONS

All very low birth weight infants with pneumothorax born during the period January 1997 through December 2002 were identified. These infants were matched to infants without pneumothorax for gestational age, birth weight, and gender. Perinatal, neonatal, and treatment variables were collected for all infants.

MEASUREMENTS AND MAIN RESULTS

Very low birth weight infants with pneumothorax were compared with those without. Univariate analysis was performed using the paired Student's t-test for continuous variables and the McNemar test for categorical variables. All variables were entered into a stepwise logistic regression model using a paired case-control design. Statistical significance was defined at p < .05. Seventy-four of 679 very low birth weight infants (10.9%) admitted to the neonatal intensive care unit developed a pneumothorax and were matched to 74 control infants. Multivariate analysis showed that only factors present on the day of pneumothorax were associated with pneumothorax. An increased risk of pneumothorax was associated with maximal, peak inspiratory pressure (odds ratio [OR] 1.33, 95% confidence interval [CI] 1.07, 1.66), minimal Fio2 (OR 2.18, 95% CI 1.14, 4.17), pulmonary hemorrhage (OR 27.5, 95% CI 2.3, 337), and maximal arterial CO2 (OR 1.94, 95% CI 1.13, 3.34), while a decreased risk was associated with maximal positive end-expiratory pressure (OR 0.71, 95% CI 0.56, 0.91).

CONCLUSIONS

Pneumothorax is associated with factors present on day of pneumothorax and not with initial ventilation variables or initial severity of lung disease. Decreasing the risk of pneumothorax requires rigorous control of ventilation, including optimizing positive end-expiratory pressure and minimizing peak inspiratory pressure.

Local delivery of VEGF adenovirus to the uterine artery increases vasorelaxation and uterine blood flow in the pregnant sheep

Impaired materno-placental perfusion causes two important obstetric complications, fetal growth restriction and preeclampsia. This study investigated whether adenoviral vector-mediated overexpression of vascular endothelial growth factor (VEGF) in the uterine arteries (UtAs) increases uterine artery blood flow (UBF). First-generation adenovirus vectors (5 x 10(11) particles) containing the VEGF gene (Ad.VEGF-A or -D) or the beta-galactosidase reporter gene (Ad.lacZ) were injected into the UtAs of pregnant sheep (n=6) at 88-102 days of gestation (term=145 days). UBF was measured using Doppler sonography before, and 4-7 days after injection. Mean UBF increased significantly from 233+/-156 (s.d.) ml min(-1) to 753+/-415 ml min(-1) following Ad.VEGF-A injection (P=0.005, n=5); Ad.lacZ infection had no significant effect. Organ bath experiments on uterine arterial sections 4-7 days after injection showed that, compared with Ad.lacZ vessels, Ad.VEGF-A-transduced vessels had a reduced contractile response to phenylephrine (E max 148+/-10.9 vs E max 228.2+/-27.5, P<0.05) but increased relaxation with bradykinin (pD2 (-log EC50) values 9.11+/-0.01 vs 8.65+/-0.11, P<0.05). Injection of Ad.VEGF-A into the UtAs increases UBF by enhancing vasodilatation. This may provide the basis for therapy in pregnancies complicated by uteroplacental insufficiency.

Disparities in asthma hospitalizations among children seen in the emergency department

We examined the race/ethnicity variation in the risk of hospitalization among children seen in the emergency department (ED) for asthma. ED and hospitalization records for children 1 to 19 years of age in New Jersey for 2004 and 2005 were linked. The dataset identified 47,548 ED and hospitalizations among 37,216 children. ED and hospitalization rates indicated persistent disparities in pediatric asthma. ED admission rates were similar across race/ethnic groups, suggesting similar management of pediatric asthma patients once they are seen in the ED. Integrating existing ED and hospitalization records will enhance asthma surveillance and the targeting of interventions to reduce race/ethnicity disparities.

Maternal vagal tone change in response to methadone is associated with neonatal abstinence syndrome severity in exposed neonates

OBJECTIVE

Though methadone pharmacotherapy is the treatment of choice for opiate-dependence during pregnancy in the USA, most methadone-exposed neonates develop neonatal abstinence syndrome (NAS). NAS expression is widely variable among methadone-exposed neonates and only a subset requires pharmacotherapy. This study explores the potential predictors of NAS severity, including aspects of maternal substance use and methadone maintenance histories, concomitant exposure to other licit substances, and individual differences in intrinsic maternal or infant factors that may affect the infant's vulnerability to NAS expression.

METHODS

Fifty methadone-maintained pregnant women attending a comprehensive substance abuse treatment facility, received electrocardiogram monitoring at 36 weeks of gestation at the times of trough and peak maternal methadone levels. Vagal tone, an estimate of the magnitude of an individual's respiratory sinus arrhythmia and an indicator of autonomic control, was derived.

RESULTS

NAS expression was unrelated to maternal substance abuse history, methadone maintenance history, or psychotropic medication exposure. Male infants displayed more profound NAS symptoms and received more pharmacotherapy to treat NAS (all p < 0.05). NAS expression was related to maternal vagal reactivity; both suppression and activation of maternal vagal tone in response to methadone administration were positively and significantly associated with NAS symptomatology (F (2,44) = 4.15, p < 0.05) and treatment (F (2,44) = 3.39, p < 0.05). Infants of vagal non-responder mothers showed substantially lower NAS expression.

CONCLUSIONS

NAS severity is associated with maternal vagal tone change in response to methadone administration.

Neuropsychological outcomes in children of mothers with epilepsy

The study investigated the nature of the effects of maternal epilepsy on cognitive performance of the offspring. One hundred fifty-four children of mothers with epilepsy aged 5 to 11 years (study group), along with 130 control children, comparable with respect to IQ, socio-economic status, age, and gender underwent a neuropsychological assessment using subtests from the NEPSY: A Developmental Neuropsychological Assessment, tapping attentional, auditory-verbal, visuomotor, fine motor, and memory abilities. The study group scored significantly lower than the controls on measures of attention, memory, and fine-motor function. Deficits were more marked in but not limited to the subset of the study group exposed to maternal medication in utero. Group differences on auditory attention were found only in younger children. Valproate-exposed children obtained lower scores on sentence repetition, as well as on the more demanding part of a test of auditory attention, than other children in the study group, suggesting weaknesses in working memory in the former subgroup. Confounding by maternal epilepsy type and polytherapy complicate interpretation of this finding. Differences between subsets of children not exposed to anti-epileptic drugs in utero and controls suggest that both drug exposure and genetic factors may contribute to cognitive deficits associated with maternal epilepsy.

Lung function in infants and young children with chronic lung disease of infancy: the next steps?

Over the past year, a series of papers have reviewed the literature concerning assessment and interpretation of lung function in infants and young children with chronic lung disease of infancy. This manuscript, which represents the final paper in that series, summarizes the findings to date and highlights key areas for future research. Despite the huge literature in this field, interpretation of results and their use in guiding clinical management are still limited by difficulties in 'normalizing data' according to body size and maturation and selection of appropriate control groups. Furthermore, sensitive tests that more closely reflect the underlying pathophysiology of 'new' bronchopulmonary dysplasia, together with simple and reliable methods of assessing lung maturity at birth and true oxygen requirements at specified time points are urgently required. Research in this field is also challenged by the need to separate the independent effects of genetic predisposition, gene-environment interactions, preterm delivery, neonatal respiratory disorders and various treatment strategies on the growing lung. The extent to which disruption of lung growth following premature exposure to the extra-uterine environment leads to an earlier or more aggravated decline in respiratory function in later adult life remains to be elucidated. Whatever its origin, given the increasing survival of smaller and more immature infants, the long term sequelae of neonatal lung disease, are likely to continue to change, requiring ongoing, carefully designed longitudinal studies. Future research strategies need to encompass a multicenter, multi-disciplinary, collaborative approach with closer links between clinicians and basic scientists, to ensure that the most relevant research questions are addressed using appropriate methodology and that findings are implemented into clinical practice in a more timely fashion.

Sex differences in electrocortical activity in human neonates

Cerebral cortical activity in healthy, full-term human neonates (10 boys and 10 girls) was evaluated using spectral estimation of electroencephalogram frequency content with new equipment and analysis technique allowing the assessment of the lowest frequencies (i.e. infraslow waves). The activity was analysed under quiet sleep and active wakefulness taking sex into consideration. During sleep, the mean amount of infraslow activity was 27% larger in boys, whereas during wakefulness the average amount of higher frequencies was 17% larger in girls. Both these differences indicate an earlier maturation of cortical function in girls than in boys.