Changing long-term outcomes for infants 500-999 g birth weight in Victoria, 1979-2005

Cerebrovascular Autoregulation in Preterm Infants Using Heart Rate or Blood Pressure: A Pilot Study

BACKGROUND

Cerebrovascular autoregulation (CAR) is often impaired in preterm infants but requires invasive mean arterial blood pressure (MABP) measurements for continuous assessment. We aimed to assess whether using heart rate (HR) results in different CAR assessment compared with using MABP.

METHODS

We compared CAR (moving window correlation-coefficient with cerebral oxygenation saturation (rcSO2)), and percentage of time with impaired CAR (%timeCARi) calculated by either HR (TOHRx, tissue oxygenation heart rate reactivity index) or MABP (COx, cerebral oximetry index) during the first 72 h after birth, and its association with short-term cerebral injury.

RESULTS

We included 32 infants, median gestational age of 25 + 5/7 weeks (interquartile range 24 + 6/7-27 + 5/7). COx and TOHRx correlation coefficients (cc) were significantly different in the first two days after birth (individual means ranging from 0.02 to 0.07 and -0.05 to 0.01). %TimeCARi using MABP (cc cut-off 0.3), was higher on day 1 (26.1% vs. 17.7%) and day 3 (23.4% vs. 16.9%) compared with HR (cc cutoff -0.3). During 65.7-69.6% of the time, both methods indicated impaired CAR simultaneously. The aforementioned calculations were not associated with early cerebral injury.

CONCLUSIONS

In conclusion, HR and MABP do not seem interchangeable when assessing CAR in preterm infants.

Mortality in the neonatal intensive care setting: Do benchmarks tell the whole story?

AIM

Australian neonatal mortality data are collected and shared within collaborative networks. Individual unit outcomes are benchmarked between units and presented in quarterly or yearly reports. Low mortality is commonly interpreted as optimal performance. However, current collected data do not differentiate between death due to severe illness and death following treatment limitation. This study aims to explore the physiological condition immediately before death, and the proportion of deaths attributed to treatment limitation.

METHODS

This retrospective single centre study of 100 consecutive deaths classified the physiological condition 12 h prior to death as stable or unstable using a clinical illness score based upon pH, oxygen saturation index, medications and blood product use. Documented discussions regarding expected outcomes and goals of management were reviewed for agreed upon treatment limitations and analysed against physiological stability.

RESULTS

Causes of death were sepsis (n = 24), congenital anomalies (n = 20), extreme prematurity (n = 19), hypoxic ischaemic encephalopathy (n = 18), intraventricular haemorrhage (n = 11) and other (n = 8). Forty-eight infants were physiologically stable at 12 h before death. In infants classified as physiologically stable, 90% of deaths were in a scenario where palliative care was discussed and intensive care treatment was ceased. These deaths accounted for 43% of total mortality in our unit.

CONCLUSION

A large portion of mortality in our unit could be attributed to treatment limitations in physiologically stable infants with high risk of neurodevelopmental impairment. Our study emphasises the need to consider the physiological status around time of death for optimal benchmarking of mortality between neonatal units.

Expiratory airflow at 7-8 years of age in children born extremely low birthweight from 14 years before to 14 years after the introduction of exogenous surfactant

Background

It is unclear if expiratory airflow in survivors born extremely low birth weight (ELBW; 500-999 g) has improved after the introduction of exogenous surfactant into clinical practice in 1991. The primary aim of this study was to describe the changes in airflow at 7-8 years of age of survivors born ELBW in five discrete cohorts from 14 years before to 14 years after the introduction of exogenous surfactant into clinical practice.

Methods

The cohorts comprised consecutive survivors born ELBW in 1977-82 and 1985-87 at the Royal Women's Hospital, Melbourne, and in 1991-92, 1997 and 2005 in the state of Victoria, Australia. Survival rates to 2-years of age for infants born ELBW in the state of Victoria rose from approximately 1-in-4 to 3-in-4 over the time of this study. Expiratory airflow measurements at 7-8 years included the forced expired volume in 1 s (FEV1), converted to z-scores for age, height, sex, and race.

Findings

There were 596 ELBW participants with expiratory flow data, 280 (47%) of whom had bronchopulmonary dysplasia (BPD). Overall, there was little change in zFEV1 over the 28-year period (mean change per year; 0.003, 95% CI -0.010, 0.015, P = 0.67). There was, however, evidence of an interaction between BPD and year; zFEV1 in those who had BPD fell over time (mean change per year -0.019, 95% CI -0.037, -0.009, P = 0.035), whereas zFEV1 improved in those who did not have BPD (mean change per year 0.021, 95% CI 0.006, 0.037, P = 0.007).

Interpretation

Contrary to recent evidence, expiratory airflow of children born ELBW has not improved with the introduction of surfactant, and may be deteriorating in those who had BPD.

Funding

National Health and Medical Research Council (Australia); Victorian Government's Operational Infrastructure Support Program.

Brain Development and Maternal Behavior in Relation to Cognitive and Language Outcomes in Preterm-Born Children

BACKGROUND

Children born very preterm (≤32 weeks gestational age) show poorer cognitive and language development compared with their term-born peers. The importance of supportive maternal responses to the child's cues for promoting neurodevelopment is well established. However, little is known about whether supportive maternal behavior can buffer the association of early brain dysmaturation with cognitive and language performance.

METHODS

Infants born very preterm (N = 226) were recruited from the neonatal intensive care unit for a prospective, observational cohort study. Chart review (e.g., size at birth, postnatal infection) was conducted from birth to discharge. Magnetic resonance imaging, including diffusion tensor imaging, was acquired at approximately 32 weeks postmenstrual age and again at term-equivalent age. Fractional anisotropy, a quantitative measure of brain maturation, was obtained from 11 bilateral regions of interest in the cortical gray matter. At 3 years (n = 187), neurodevelopmental testing (Bayley Scales of Infant and Toddler Development-III) was administered, and parent-child interaction was filmed. Maternal behavior was scored using the Emotional Availability Scale-IV. A total of 146 infants with neonatal brain imaging and follow-up data were included for analysis. Generalized estimating equations were used to examine whether maternal support interacted with mean fractional anisotropy values to predict Cognitive and Language scores at 3 years, accounting for confounding neonatal and maternal factors.

RESULTS

Higher maternal support significantly moderated cortical fractional anisotropy values at term-equivalent age to predict higher Cognitive (interaction term β = 2.01, p = .05) and Language (interaction term β = 1.85, p = .04) scores.

CONCLUSIONS

Findings suggest that supportive maternal behavior following early brain dysmaturation may provide an opportunity to promote optimal neurodevelopment in children born very preterm.

Parent-recorded videos of infant spontaneous movement: Comparisons at 3-4 months and relationships with 2-year developmental outcomes in extremely preterm, extremely low birthweight and term-born infants

BACKGROUND

Infants born extremely preterm (EP, <28-week gestational age) or extremely low birthweight (ELBW, <1000 g) are at risk of developmental delay and cerebral palsy (CP). The General Movements Assessment (GMA) and its extension, the Motor Optimality Score, revised (MOS-R) (assesses movement patterns and posture), may help to identify early delays.

OBJECTIVES

To compare differences in the MOS-R scored from parent-recorded videos between infants born EP/ELBW and term-born infants, to determine relationships between the MOS-R and 2-year cognitive, language and motor outcomes and if any relationships differ between birth groups and the association of the GMA (fidgety) with CP.

METHODS

A geographical cohort (EP/ELBW and term-control infants) was assessed using the MOS-R inclusive of the GMA at 3- to 4-month corrected age (CA), and the Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) at 2-year CA. Differences in mean total MOS-R between groups, relationships between MOS-R and 2-year outcomes and relationships between GMA (fidgety) and CP in infants born EP/ELBW were estimated using linear/logistic regression.

RESULTS

Three hundred and twelve infants (147 EP/ELBW; 165 term) had complete MOS-R and Bayley-III assessments. Mean MOS-R was lower in infants born EP/ELBW than controls (mean difference -3.2, 95% confidence interval [CI] -4.2, -2.3). MOS-R was positively related to cognitive (β [regression coefficient] = 0.71, 95% CI 0.27, 1.15), language (β = 0.96, 95% CI 0.38, 1.54) and motor outcomes (β = .89, 95% CI 0.45, 1.34). There was little evidence for interaction effects between birth groups for any outcome. Absent/abnormal fidgety movements were related to CP in children born EP/ELBW (risk ratio 5.91, 95% CI 1.48, 23.7).

CONCLUSIONS

Infants born EP/ELBW have lower MOS-R than infants born at term. A higher MOS-R is related to better outcomes for 2-year development, with similar relationships in both birth groups. Absent/abnormal fidgety movements are related to CP in EP/ELBW survivors.

Trends in survival, perinatal morbidities and two-year neurodevelopmental outcomes in extremely low-birthweight infants over four decades

BACKGROUND

Although outcomes for infants born extremely low birthweight (ELBW; <1000 g birthweight) have improved over time, it is important to document survival and morbidity changes following the advent of modern neonatal intensive care in the 1990s.

OBJECTIVE

To describe trends in survival, perinatal outcomes and neurodevelopment to 2 years' corrected age over time across six discrete geographic cohorts born ELBW between 1979 and 2017.

METHODS

Analysis of data from discrete population-based prospective cohort studies of all live births free of lethal anomalies with birthweight 500-999 g in the state of Victoria, Australia, over 6 eras: 1979-80, 1985-87, 1991-92, 1997, 2005 and 2016-17. Perinatal data collected included survival, duration and type of respiratory support, neonatal morbidities and two-year neurodevelopmental outcomes.

RESULTS

More ELBW live births were inborn (born in a maternity hospital with a neonatal intensive care unit) over time (1979-80, 70%; 2016-17, 84%), and more were offered active care (1979-80, 58%; 2016-17, 90%). Survival to 2 years rose substantially, from 25% in 1979-80 to 80% in 2016-17. In survivors, rates of any assisted ventilation rose from 75% in 1979-80 to 99% in 2016-17. Cystic periventricular leukomalacia, severe retinopathy of prematurity and blindness improved across eras. Two-year data were available for 95% (1054/1109) of survivors. Rates of cerebral palsy, deafness and major neurodevelopmental disability changed little over time. The annual numbers with major neurodevelopmental disability increased from 12.5 in 1979-80 to 30 in 2016-17, but annual numbers free of major disability increased much more, from 31 in 1979-80 to 147 in 2016-17.

CONCLUSIONS

Active care and survival rates in ELBW children have increased dramatically since 1979 without large changes in neonatal morbidities. The numbers of survivors free of major neurodevelopmental disability have increased more over time than those with major disability.

The causal effect of being born extremely preterm or extremely low birthweight on neurodevelopment and social-emotional development at 2 years

AIM

To assess the causal effect of being born extremely preterm (EP; <28 weeks' gestation) or extremely low birthweight (ELBW; <1000 g), compared with being born at term, on neurodevelopment and social-emotional development at 2 years' corrected age.

METHODS

Prospective geographical cohort study of children born EP/ELBW over 12 months in 2016 from Victoria, Australia, and term-born controls. Children were assessed at 2 years' corrected age with the Bayley Scales of Infant and Toddler Development-3rd edition and the Infant-Toddler Social and Emotional Assessment. Delay was defined as <-1 standard deviation relative to the mean of controls. The estimand of interest was the mean difference/odds ratio (OR) between the EP/ELBW and control groups estimated using linear/logistic regression, adjusted for multiple pregnancy and social risk.

RESULTS

A total of 205 EP/ELBW and 201 controls were assessed at 2 years. Delay/concerns were more common in the EP/ELBW group compared with controls, for cognitive (OR 3.7 [95% confidence interval 2.3, 6.0]), language (5.3 [3.1, 9.0]) and motor (3.9 [2.3, 6.3]) development, and social-emotional competence (4.1 [1.6, 10.2]).

CONCLUSION

Being born EP/ELBW has an adverse effect on cognitive, language and motor development, and social-emotional competence at 2 years' corrected age. Close developmental surveillance, including social-emotional development, is recommended.

The changing face of neonatal intensive care for infants born extremely preterm (<28 weeks' gestation)

Neonatal intensive care for infants born extremely preterm (<28 weeks' gestation) has changed dramatically over the past 60-70 years. From little care being available and few infants surviving in the first half of the 20th century, more intensive care and rapidly increasing survival rates followed in the second half, and have continued to rise into the 21st century. However, mistakes were made along the way. The purpose of this article is to recollect some of the pivotal changes in neonatal intensive care of infants born extremely preterm, and the consequences of those changes. Changes in attitudes, the physical environment, staffing, and basic treatments, such as oxygen and assisted ventilation, and evidence-based care are all discussed. Neonatal intensive care will continue to evolve, but in so doing we must learn from past mistakes in order to avoid repeating them.

Mortality Rate and Major Causes of Death by Gestational Age in Korean Children under 5 Years of Age

BACKGROUND

Preterm birth is associated with increased infant mortality. However, it is not clear whether prematurity is associated with mortality after 1 year of age. There is a lack of research on mortality rate and causes of death after infancy in preterm babies in Korea. We aimed to analyze the mortality rates and causes of deaths up to 5 years of age in Korea.

METHODS

Using the Microdata Integrated Service of Statistics Korea database, this retrospective cohort study screened infants born between 2010 and 2012. After applying the exclusion criteria, 1,422,913 live births were classified into the following groups by gestational age: those born at < 32 weeks' gestation (n = 10,411), those born between 32 and 36 weeks' gestation (n = 75,657), and those born at ≥ 37 weeks' gestation (n = 1,336,845). The association of gestational age with mortality in infancy (< 1 year of age) and childhood (1-5 years of age) was analyzed, with and without covariates. The major causes of death in infancy and childhood were analyzed by gestational age.

RESULTS

Overall, 4,930 (0.3%) children died between birth and 5 years of age, with 19.1% of these deaths occurring after infancy. Adjusted hazard ratios (HRs) for infant death were 78.79 (95% confidence interval [CI], 71.33-87.04) and 4.62 (95% CI, 4.07-5.24) for the < 32 and 32-36 weeks groups, respectively, compared to the full-term group; the adjusted HRs for deaths occurring at ages 1-5 years were 9.25 (95% CI, 6.85-12.50) and 2.42 (95% CI, 1.95-3.01), respectively. In infancy, conditions originating in the perinatal period were the most common cause of deaths in the < 32 and 32-36 weeks groups (88.7% and 41.9%, respectively). Contrarily, in the ≥ 37 weeks group, conditions originating in the perinatal period explained 22.7% of infant deaths, with congenital malformations primarily accounting for 29.6% of these deaths. The most common cause of death in children (after infancy) in the < 32 weeks group was perinatal causes (25.0%); in the 32-36 weeks group, congenital malformation and nervous system disease were the common causes (21.7% and 19.1%, respectively). In the ≥ 37 weeks group, injury, poisoning, and other consequences of external causes explained 26.6% of childhood deaths, followed by neoplasms and nervous system disease (15.7% and 14.7%, respectively).

CONCLUSION

Low gestational age is associated with not only infant mortality but also child mortality. The major causes of death differed by gestational age in infancy and childhood. For the care of preterm infants, especially those born at < 32 weeks' gestation, particular attention and continuous monitoring are needed in consideration of the major causes of deaths until 5 years of age.

Postnatal adaptations of phosphatidylcholine metabolism in extremely preterm infants: implications for choline and PUFA metabolism

BACKGROUND

Lipid metabolism in pregnancy delivers PUFAs from maternal liver to the developing fetus. The transition at birth to diets less enriched in PUFA is especially challenging for immature, extremely preterm infants who are typically supported by total parenteral nutrition.

OBJECTIVE

The aim was to characterize phosphatidylcholine (PC) and choline metabolism in preterm infants and demonstrate the molecular specificity of PC synthesis by the immature preterm liver in vivo.

METHODS

This MS-based lipidomic study quantified the postnatal adaptations to plasma PC molecular composition in 31 preterm infants <28 weeks' gestational age. Activities of the cytidine diphosphocholine (CDP-choline) and phosphatidylethanolamine-N-methyltransferase (PEMT) pathways for PC synthesis were assessed from incorporations of deuterated methyl-D9-choline chloride.

RESULTS

The concentration of plasma PC in these infants increased postnatally from median values of 481 (IQR: 387-798) µM at enrollment to 1046 (IQR: 616-1220) µM 5 d later (P < 0.001). Direct incorporation of methyl-D9-choline demonstrated that this transition was driven by an active CDP-choline pathway that synthesized PC enriched in species containing oleic and linoleic acids. A second infusion of methyl-D9-choline chloride at day 5 clearly indicated continued activity of this pathway. Oxidation of D9-choline through D9-betaine resulted in the transfer of 1 deuterated methyl group to S-adenosylmethionine. A very low subsequent transfer of this labeled methyl group to D3-PC indicated that liver PEMT activity was essentially inactive in these infants.

CONCLUSIONS

This study demonstrated that the preterm infant liver soon after birth, and by extension the fetal liver, was metabolically active in lipoprotein metabolism. The low PEMT activity, which is the only pathway for endogenous choline synthesis and is responsible for hormonally regulated export of PUFAs from adult liver, strongly supports increased supplementation of preterm parenteral nutrition with both choline and PUFAs.

Treatment for hypotension in the first 24 postnatal hours and the risk of hearing loss among extremely low birth weight infants

OBJECTIVE

To evaluate whether treated hypotension in the first 24 postnatal hours is associated with hearing loss in extremely low birth weight (ELBW) infants.

STUDY DESIGN

In a cohort of 735 ELBW infants, we identified 25 with sensorineural hearing loss (SNHL) at 12-24 months adjusted age. For each case, we selected three controls with normal hearing. Logistic regression models were used to adjust for confounding variables.

RESULTS

Sixty percent of cases and 25% of controls were treated for hypotension. After adjusting for confounding variables (gestational age, antenatal glucocorticoids, 5 min Apgar < 6, insertion of an umbilical catheter, treatment with high frequency ventilation, and major cranial ultrasound abnormality), treated hypotension was associated with an increased risk of SNHL (adjusted odds ratio: 3.6; 95% confidence interval: 1.3-9.7).

CONCLUSIONS

Treated hypotension in ELBW infants in the first 24 h of life is associated with an increased risk of SNHL.

Secular trends of birthweight in boys from 1950 to 2010

BACKGROUND

Birthweight is an indicator of fetal development and intrauterine conditions and is associated with future health outcomes. Secular birthweight trends prior to the 1970s are mostly unknown. Our aim was to explore secular birthweight trends in Swedish boys from 1950 to 2010.

METHODS

We have collected detailed growth data including birthweight from archived School Health Care records for children born in Gothenburg from 1946 and onwards and established a unique population-based cohort, the Body Mass Index Epidemiology Study (BEST). The birthweight cohort spans six decades (1950-2010) and includes 46,548 boys.

RESULTS

The mean birthweight of the complete study cohort was 3580 ± 562 g. Linear regression analysis of the entire period revealed a minimal negative secular trend for birthweight (BETA = -0.4 g/year; p < 0.01). However, three distinct trends appeared during sub-periods: a decrease 1950-80, an increase 1980-2000 and another decrease 2000-2010.

CONCLUSION

We demonstrate that birthweight in boys has undergone periodic decreases and subsequent increases, but the overall trend from the 1950s to the present is stable.

Working Memory Training Is Associated with Changes in Resting State Functional Connectivity in Children Who Were Born Extremely Preterm: a Randomized Controlled Trial

Children born extremely preterm (EP; < 28 weeks of gestation) or extremely low birth weight (ELBW; < 1000 g) are at increased risk of working memory deficits compared with their term-born peers and may benefit from working memory training. This study aimed to determine whether Cogmed Working Memory Training®, compared with a placebo training program, was associated with changes in resting-state functional connectivity (rsfc) and whether these changes correlated with working memory performance in EP/ELBW children. Twenty-one 7-year-old EP/ELBW children were enrolled in a double-blinded randomized controlled trial and had magnetic resonance imaging (MRI) assessments (Cogmed, n = 12; placebo (a non-adaptive version of Cogmed), n = 9). Prior to training (baseline) and 2 weeks post-training, all children received a cognitive assessment, inclusive of immediate memory and working memory measures and an MRI. The Cogmed Improvement Index was used as a measure of improvement in trained activities in the Cogmed group. Resting-state functional MRI was used to measure training-related changes in intra- and inter-network rsfc. The networks assessed include the default mode network, the left and right central executive networks, the bilateral executive network, the dorsal attention network, and the salience network. rsfc data were compared between treatment groups and investigated in relation to changes in working memory performance. There was little evidence of differences in intra- or inter-network rsfc strength changes from baseline to post-training between treatment groups. In the Cogmed group, working memory performance was associated with increased rsfc from baseline to post-training within the precuneus network, but not in the placebo group. In the Cogmed group, results that did not survive multiple comparison correction further showed that improvement in trained activities was associated with increased rsfc between the left central and bilateral executive networks, and with decreased rsfc within the right central executive network and between the right central executive and salience networks. Changes in rsfc may facilitate working memory performance following Cogmed training. Further studies are needed to investigate how changes in rsfc are associated with behavioral changes to better support working memory in vulnerable groups.

Developing routinely recorded clinical data from electronic patient records as a national resource to improve neonatal health care: the Medicines for Neonates research programme

Background

Clinical data offer the potential to advance patient care. Neonatal specialised care is a high-cost NHS service received by approximately 80,000 newborn infants each year.

Objectives

(1) To develop the use of routinely recorded operational clinical data from electronic patient records (EPRs), secure national coverage, evaluate and improve the quality of clinical data, and develop their use as a national resource to improve neonatal health care and outcomes. To test the hypotheses that (2) clinical and research data are of comparable quality, (3) routine NHS clinical assessment at the age of 2 years reliably identifies children with neurodevelopmental impairment and (4) trial-based economic evaluations of neonatal interventions can be reliably conducted using clinical data. (5) To test methods to link NHS data sets and (6) to evaluate parent views of personal data in research.

Design

Six inter-related workstreams; quarterly extractions of predefined data from neonatal EPRs; and approvals from the National Research Ethics Service, Health Research Authority Confidentiality Advisory Group, Caldicott Guardians and lead neonatal clinicians of participating NHS trusts.

Setting

NHS neonatal units.

Participants

Neonatal clinical teams; parents of babies admitted to NHS neonatal units.

Interventions

In workstream 3, we employed the Bayley-III scales to evaluate neurodevelopmental status and the Quantitative Checklist of Autism in Toddlers (Q-CHAT) to evaluate social communication skills. In workstream 6, we recruited parents with previous experience of a child in neonatal care to assist in the design of a questionnaire directed at the parents of infants admitted to neonatal units.

Data sources

Data were extracted from the EPR of admissions to NHS neonatal units.

Main outcome measures

We created a National Neonatal Research Database (NNRD) containing a defined extract from real-time, point-of-care, clinician-entered EPRs from all NHS neonatal units in England, Wales and Scotland (n = 200), established a UK Neonatal Collaborative of all NHS trusts providing neonatal specialised care, and created a new NHS information standard: the Neonatal Data Set (ISB 1595) (see http://webarchive.nationalarchives.gov.uk/±/http://www.isb.nhs.uk/documents/isb-1595/amd-32–2012/index_html; accessed 25 June 2018).

Results

We found low discordance between clinical (NNRD) and research data for most important infant and maternal characteristics, and higher prevalence of clinical outcomes. Compared with research assessments, NHS clinical assessment at the age of 2 years has lower sensitivity but higher specificity for identifying children with neurodevelopmental impairment. Completeness and quality are higher for clinical than for administrative NHS data; linkage is feasible and substantially enhances data quality and scope. The majority of hospital resource inputs for economic evaluations of neonatal interventions can be extracted reliably from the NNRD. In general, there is strong parent support for sharing routine clinical data for research purposes.

Limitations

We were only able to include data from all English neonatal units from 2012 onwards and conduct only limited cross validation of NNRD data directly against data in paper case notes. We were unable to conduct qualitative analyses of parent perspectives. We were also only able to assess the utility of trial-based economic evaluations of neonatal interventions using a single trial. We suggest that results should be validated against other trials.

Conclusions

We show that it is possible to obtain research-standard data from neonatal EPRs, and achieve complete population coverage, but we highlight the importance of implementing systematic examination of NHS data quality and completeness and testing methods to improve these measures. Currently available EPR data do not enable ascertainment of neurodevelopmental outcomes reliably in very preterm infants. Measures to maintain high quality and completeness of clinical and administrative data are important health service goals. As parent support for sharing clinical data for research is underpinned by strong altruistic motivation, improving wider public understanding of benefits may enhance informed decision-making.

Future work

We aim to implement a new paradigm for newborn health care in which continuous incremental improvement is achieved efficiently and cost-effectively by close integration of evidence generation with clinical care through the use of high-quality EPR data. In future work, we aim to automate completeness and quality checks and make recording processes more ‘user friendly’ and constructed in ways that minimise the likelihood of missing or erroneous entries. The development of criteria that provide assurance that data conform to prespecified completeness and quality criteria would be an important development. The benefits of EPR data might be extended by testing their use in large pragmatic clinical trials. It would also be of value to develop methods to quality assure EPR data including involving parents, and link the NNRD to other health, social care and educational data sets to facilitate the acquisition of lifelong outcomes across multiple domains.

Study registration

This study is registered as PROSPERO CRD42015017439 (workstream 1) and PROSPERO CRD42012002168 (workstream 3).

Funding

The National Institute for Health Research Programme Grants for Applied Research programme (£1,641,471). Unrestricted donations were supplied by Abbott Laboratories (Maidenhead, UK: £35,000), Nutricia Research Foundation (Schiphol, the Netherlands: £15,000), GE Healthcare (Amersham, UK: £1000). A grant to support the use of routinely collected, standardised, electronic clinical data for audit, management and multidisciplinary feedback in neonatal medicine was received from the Department of Health and Social Care (£135,494).

Low-grade intraventricular hemorrhage of preterm infants: neurodevelopmental and motor outcome

Intraventricular hemorrhage (IVH) is a main complication of prematurity, inversely associated with gestational age and birth weight. Low-grade IVH (I and II), diagnosed by cranial ultrasound, had long been considered rather not to affect neurodevelopmental and motor outcome, a view challenged by several literature reports. However, diversity in studies design, periods of subjects' collection, cohort characteristics, demographic data, maternal or neonatal comorbidities, neuroimaging methods, evaluation tools, short-or-long-term follow-up by the same or different examiners, as well as other parameters and confounders make comparisons among reports very difficult, not allowing solid conclusions. Older, but also newer investigations claim both possible outcomes: impairment or not of cognitive and motor abilities in very preterm infants with low-grade IVH. Thus, the current suggestion in the relevant literature is not to rely only on the results of cranial ultrasounds, but to also implement classic, or even more advanced MRI techniques at term equivalent age to preterm infants with grade I or II IVH. In addition, the continuation of close follow-up during school age is warranted.

Outcomes and resource usage of infants born at ≤ 25 weeks gestation in Canada

Objectives

To determine the outcomes and resource usage of infants born at ≤ 25 weeks gestational age (GA).

Methods

Retrospective study of infants born between April 2009 and September 2011 at ≤ 25 weeks' GA in all neonatal intensive care units in Canada with follow-up in the neonatal follow-up clinics. Short-term morbidities, neurodevelopmental impairment, significant neurodevelopmental impairment, and resource utilization of infants born at ≤ 24 weeks were compared with neonates born at 25 weeks.

Results

Of 803 neonates discharged alive, 636 (80.4%) infants born at ≤ 25 weeks' GA were assessed at 18 to 24 months. Caesarean delivery, lower birth weight, and less antenatal steroid exposure were more common in infants born ≤ 24 weeks as compared with 25 weeks. They had significantly higher incidences of ductus arteriosus ligation, severe intracranial hemorrhage, retinopathy of prematurity as well as longer length of stay, central line days, days on respiratory support, days on total parenteral nutrition, days on antibiotics, and need for postnatal steroids. Neurodevelopmental impairment rates were 68.9, 64.5, and 55.6% (P=0.01) and significant neurodevelopmental impairment rates were 39.3, 29.6, and 20.9% (P<0.01) for infants ≤ 23, 24, and 25 weeks GA, respectively. Postdischarge service referrals were higher for those ≤ 23 weeks. Nonsurviving infants born at 25 weeks GA had higher resource utilization during admission than infants born less than 25 weeks.

Conclusions

Adverse outcomes and resource usage were significantly higher among infants born ≤ 24 weeks GA as compared with 25 weeks GA.

Trends in the incidence and associated factors of late-onset sepsis associated with improved survival in extremely preterm infants born at 23-26 weeks' gestation: a retrospective study

Background

To investigate the trends in the incidence and associated factors of late-onset sepsis (LOS) associated with improved survival in extremely preterm infants.

Methods

Medical records of 364 infants who were born at 23–26 weeks’ gestation from 2000 to 2005 (period I, n = 124) and from 2006 to 2011 (period II, n = 240) were retrospectively reviewed. The infants were stratified into subgroups of 23–24 and 25–26 weeks’ gestation within each period, and survival, LOS rate, and clinical characteristics were analyzed. Multivariate logistic regression analyses were completed to identify the clinical factors associated with LOS.

Results

The survival rate of 75.8% during period I significantly improved to 85.4% during period II, especially in infants at 23–24 weeks’ gestation (55.1% vs. 78.1%, respectively). The LOS rate of 33.1% during period I significantly reduced to 15.8% during period II, especially in infants at 25–26 weeks’ gestation (32.0% vs. 8.9%, respectively). The LOS rate per 1000 hospital days of 4.0 during period I significantly reduced to 1.8 during period II. Candida presence reduced from 21.3% during period I to 4.7% during period II. In multivariate analyses, during period I, prolonged intubation, especially in infants at 25–26 weeks’ gestation, and necrotizing enterocolitis, especially in infants at 23–24 weeks’ gestation, were significantly associated with LOS.

Conclusions

Improved survival of infants at 23–24 weeks’ gestation was associated with a simultaneous reduction of LOS incidence in infants at 25–26 weeks’ gestation. Less-invasive assisted ventilation may be one of the details of improved perinatal and neonatal care that has contributed to lowering risk of infection or death among periviable infants.

Electronic supplementary material

The online version of this article (10.1186/s12887-018-1130-y) contains supplementary material, which is available to authorized users.

Rates of early intervention services in children born extremely preterm/extremely low birthweight

AIM

To determine the rates of early intervention (EI) service use in extremely preterm (EP, <28 weeks' gestation) or extremely low birthweight (ELBW, <1000 g) infants between 1991 and 2013, and identify biological or socio-economic factors associated with receiving EI.

METHODS

Participants comprised consecutive EP or ELBW survivors born in 1991-1992, 1997 or 2005 in Victoria, Australia, and randomly selected, matched term-born controls. The main outcome measure was parent-reported EI participation up to 8 years of age. Neurodevelopmental outcomes and socio-economic risk factors were compared with EI participation to identify associations among the preterm groups.

RESULTS

The rates of EI were higher in the preterm groups than the control groups overall (odds ratio 4.29, 95% confidence interval 3.28, 5.59, P < 0.001), and the rates of EI rose significantly over time - from 42% in the 1991-1992 preterm cohort to 64% in the 2005 preterm cohort. Among the preterm groups, post-natal corticosteroid therapy, cystic periventricular leukomalacia and surgery in the newborn period were all independently associated with increased odds of receiving EI. Increased severity of disability was associated with higher rates of EI. The majority (95%) of preterm children with a physical impairment received EI, compared with only 73% of children with a cognitive impairment alone. EI participation rates were independent of social risk.

CONCLUSION

EI participation is high in the EP population, and rates of EI use have increased over time. Contrary to previous reports, social risk factors were not found to be associated with EI use.

Seven Years Cognitive Functioning and Early Assessment in Extremely Low Birth Weight Children

Infants born preterm are at high risk for the onset of cognitive dysfunctions at school age. The aim of this study was to investigate the association between early neurodevelopmental assessment and the risk of adverse cognitive outcome in extremely low birth weight children. We enrolled all newborns (January 2002 – April 2007) consecutively admitted to our Institution, with a birthweight < 1000 g. Exclusion criteria were genetic abnormalities, severe neurofunctional impairment, and/or neurosensory disabilities. Ninety-nine children were assessed at 1 year of corrected age using the Griffiths Mental Development Scales Revised. The same children were re-assessed at school age through the Wechsler Intelligence Scale for Children. Children with impaired Griffiths General Quotient (i.e., <1 SD) at 1 year of corrected age showed a significantly lower Full Scale Intelligence Quotient at 7 years of chronological age when compared to children who scored in the normal range at 1 year (p < 0.01). Considering the Griffiths Sub-quotients separately, a poor score in the Performance or in the Personal-Social Sub-quotients at 1 year was associated with significantly worse cognitive outcomes both in the Verbal and in the Performance Intelligence Quotients at 7 years (p < 0.01 and p < 0.05, respectively). A score <1 SD in the Locomotor or in the Eye and Hand Coordination Sub-quotients were specifically associated with poorer Performance or Verbal Intelligence Quotients, respectively (p < 0.05). Our findings suggest that a poor score on the Griffiths Scales at 1 year is associated with a higher risk of cognitive impairment at school age. Larger confirmation studies are needed.

Decline in the negative association between low birth weight and cognitive ability

Low birth weight predicts compromised cognitive ability. We used data from the 1958 National Child Development Study (NCDS), the 1970 British Cohort Study (BCS), and the 2000-2002 Millennium Cohort Study (MCS) to analyze how this association has changed over time. Birth weight was divided into two categories, <2,500 g (low) and 2,500-4,500 g (normal) and verbal cognitive ability was measured at the age of 10 or 11 y. A range of maternal and family characteristics collected at or soon after the time of birth were considered. Linear regression was used to analyze the association between birth weight and cognitive ability in a baseline model and in a model that adjusted for family characteristics. The standardized difference (SD) in cognitive scores between low-birth-weight and normal-birth-weight children was large in the NCDS [-0.37 SD, 95% confidence interval (CI): -0.46, -0.27] and in the BCS (-0.34, 95% CI: -0.43, -0.25) cohorts, and it was more than halved for children born in the MCS cohort (-0.14, 95% CI: -0.22, -0.06). The adjustment for family characteristics did not explain the cross-cohort differences. The results show that the association between low birth weight and decreased cognitive ability has declined between the 1950s and 1970s birth cohorts and the 2000--2002 birth cohort, despite a higher proportion of the low-birth-weight babies having a very low birth weight (<1,500 g) in the more recent birth cohort. Advancements in obstetric and neonatal care may have attenuated the negative consequences associated with being born small.

Mortality and Morbidity of Extremely Low Birth Weight Infants in the Mainland of China: A Multi-center Study

BACKGROUND

With the progress of perinatal medicine and neonatal technology, more and more extremely low birth weight (ELBW) survived all over the world. This study was designed to investigate the short-term outcomes of ELBW infants during their Neonatal Intensive Care Unit (NICU) stay in the mainland of China.

METHODS

All infants admitted to 26 NICUs with a birth weight (BW) < l000 g were included between January l, 2011 and December 31, 2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors.

RESULTS

A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age (GA) was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants (23.3%) died and another 69 infants (26.7%) died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas (53.6% vs. 35.3%, P = 0.019). BW < 750 g and GA < 28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization.

CONCLUSIONS

Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.

The Baby Moves prospective cohort study protocol: using a smartphone application with the General Movements Assessment to predict neurodevelopmental outcomes at age 2 years for extremely preterm or extremely low birthweight infants

INTRODUCTION

Infants born extremely preterm (EP; <28 weeks' gestation) and/or with extremely low birth weight (ELBW; <1000 g birth weight) are at increased risk for adverse neurodevelopmental outcomes. However, it is challenging to predict those EP/ELBW infants destined to have long-term neurodevelopmental impairments in order to target early intervention to those in most need. The General Movements Assessment (GMA) in early infancy has high predictive validity for neurodevelopmental outcomes in preterm infants. However, access to a GMA may be limited by geographical constraints and a lack of GMA-trained health professionals. Baby Moves is a smartphone application (app) developed for caregivers to video and upload their infant's general movements to be scored remotely by a certified GMA assessor. The aim of this study is to determine the predictive ability of using the GMA via the Baby Moves app for neurodevelopmental impairment in infants born EP/ELBW.

METHODS AND ANALYSIS

This prospective cohort study will recruit infants born EP/ELBW across the state of Victoria, Australia in 2016 and 2017. A control group of normal birth weight (>2500 g birth weight), term-born (≥37 weeks' gestation) infants will also be recruited as a local reference group. Parents will video their infant's general movements at two time points between 3 and 4 months' corrected age using the Baby Moves app. Videos will be scored by certified GMA assessors and classified as normal or abnormal. Parental satisfaction using the Baby Moves app will be assessed via survey. Neurodevelopmental outcome at 2 years' corrected age includes developmental delay according to the Bayley Scales of Infant and Toddler Development-III and cerebral palsy diagnosis.

ETHICS AND DISSEMINATION

This study was approved by the Human Research and Ethics Committees at the Royal Children's Hospital, The Royal Women's Hospital, Monash Health and Mercy Health in Melbourne, Australia. Study findings will be disseminated via peer-reviewed publications and conference presentations.

Increased Steroid Excretion in Children with Extremely Low Birth Weight at a Median Age of 9.8 years

BACKGROUND

Events during foetal or early extrauterine life may affect bodily structure and/or functions and even pave the way for adult diseases.

AIMS

To find whether extremely low birth weight (ELBW) infants differ from healthy controls regarding the excretion of steroid metabolites.

METHODS

The study compared 17 female and 10 male ELBW infants, all prepubertal, aged 8-11 years, birth weight <1,000 g, with 27 age- and sex-matched controls. All were healthy at the time of the study. Height, weight and BMI did not differ between the groups. Results were adjusted according to body surface area. 36 urinary steroid metabolites were quantified by gas chromatography-mass spectrometry.

RESULTS

In the ELBW girls 33/36 steroid metabolites were higher (19 significantly) than in the controls. All 36 steroid metabolites were higher in the ELBW boys (9 significantly) than in the controls. Sums of mineralocorticoid precursors, metabolites descriptive for cortisol and parameters of adrenal androgen production were significantly higher in ELBW infants (both sexes). Only the sum of the metabolites known to be illustrative for adrenal 11β-hydroxysteroid dehydrogenase activity was not different.

CONCLUSION

Prepubertal ELBW children have an augmented urinary excretion of adrenal androgens, cortisol and mineralocorticoid precursors. These findings corroborate and help to explain the link between early-life adversity and subsequent adrenocortical function.

Developmental Assessments in Preterm Children: A Meta-analysis

CONTEXT

Developmental outcomes of very preterm (gestational age ≤32 weeks) or very low birth weight (<1500 g) children are commonly reported before age 3 years although the predictive validity for later outcomes are uncertain.

OBJECTIVE

To determine the validity of early developmental assessments in predicting school-age cognitive deficits.

DATA SOURCES

PubMed.

STUDY SELECTION

English-language studies reporting at least 2 serial developmental/cognitive assessments on the same population, 1 between ages 1 and 3 years and 1 at ≥5 years.

DATA EXTRACTION

For each study, we calculated the sensitivity, specificity, and positive and negative predictive values of early assessment for cognitive deficit (defined as test scores 1 SD below the population mean). Pooled meta-analytic sensitivity and specificity were estimated by using a hierarchical summary receiver operator characteristic curve.

RESULTS

We included 24 studies (n = 3133 children). Early assessments were conducted at 18 to 40 months and generally involved the Bayley Scales of Infant Development or the Griffiths Mental Development Scales; 11 different cognitive tests were used at school-age assessments at 5 to 18 years. Positive predictive values ranged from 20.0% to 88.9%, and negative predictive vales ranged from 47.8% to 95.5%. The pooled sensitivity (95% confidence interval) of early assessment for identifying school-age cognitive deficit was 55.0% (45.7%-63.9%) and specificity was 84.1% (77.5%-89.1%). Gestational age, birth weight, age at assessment, and time between assessments did not explain between-study heterogeneity.

LIMITATIONS

The accuracy of aggregated data could not be verified. Many assessment tools have been superseded by newer editions.

CONCLUSIONS

Early developmental assessment has poor sensitivity but good specificity and negative predictive value for school-age cognitive deficit.

Learning Disabilities in Extremely Low Birth Weight Children and Neurodevelopmental Profiles at Preschool Age

At school age extremely low birth weight (ELBW) and extremely low gestational age (ELGAN) children are more likely to show Learning Disabilities (LDs) and difficulties in emotional regulation. The aim of this study was to investigate the incidence of LDs at school age and to detect neurodevelopmental indicators of risk for LDs at preschool ages in a cohort of ELBW/ELGAN children with broadly average intelligence. All consecutively newborns 2001-2006 admitted to the same Institution entered the study. Inclusion criteria were BW < 1000 g and/or GA < 28 weeks. Exclusion criteria were severe cerebral injuries, neurosensory disabilities, genetic abnormalities, and/or a Developmental Quotient below normal limits (< 1 SD) at 6 years. The presence of learning disabilities at school age was investigated through a parent-report questionnaire at children's age range 9-10 years. Neurodevelopmental profiles were assessed through the Griffiths Mental Development Scales at 1 and 2 years of corrected age and at 3, 4, 5, and 6 years of chronological age and were analyzed comparing two groups of children: those with LDs and those without. At school age 24 on 102 (23.5%) of our ELBW/ELGAN children met criteria for LDs in one or more areas, with 70.8% comorbidity with emotional/attention difficulties. Children with LDs scored significantly lower in the Griffiths Locomotor and Language subscales at 2 years of corrected age and in the Personal-social, Performance and Practical Reasoning subscales at 5 years of chronological age. Our findings suggest that, among the early developmental indicators of adverse school outcome, there is a poor motor experimentation, language delay, and personal-social immaturity. Cognitive rigidity and poor ability to manage practical situations also affect academic attainment. Timely detection of these early indicators of risk is crucial to assist the transition to school.

All-Cause Mortality of Low Birthweight Infants in Infancy, Childhood, and Adolescence: Population Study of England and Wales

BACKGROUND

Low birthweight (LBW) is associated with increased mortality in infancy, but its association with mortality in later childhood and adolescence is less clear. We investigated the association between birthweight and all-cause mortality and identified major causes of mortality for different birthweight groups.

METHODS AND FINDINGS

We conducted a population study of all live births occurring in England and Wales between 1 January 1993 and 31 December 2011. Following exclusions, the 12,355,251 live births were classified by birthweight: 500-1,499 g (very LBW [VLBW], n = 139,608), 1,500-2,499 g (LBW, n = 759,283), 2,500-3,499 g (n = 6,511,411), and ≥3,500 g (n = 4,944,949). The association of birthweight group with mortality in infancy (<1 y of age) and childhood/adolescence (1-18 y of age) was quantified, with and without covariates, through hazard ratios using Cox regression. International Classification of Diseases codes identified causes of death. In all, 74,890 (0.61%) individuals died between birth and 18 y of age, with 23% of deaths occurring after infancy. Adjusted hazard ratios for infant deaths were 145 (95% CI 141, 149) and 9.8 (95% CI 9.5, 10.1) for the VLBW and LBW groups, respectively, compared to the ≥3,500 g group. The respective hazard ratios for death occurring at age 1-18 y were 6.6 (95% CI 6.1, 7.1) and 2.9 (95% CI 2.8, 3.1). Male gender, the youngest and oldest maternal age bands, multiple births, and deprivation (Index of Multiple Deprivation score) also contributed to increased deaths in the VLBW and LBW groups in both age ranges. In infancy, perinatal factors, particularly respiratory issues and infections, explained 84% and 31% of deaths in the VLBW and LBW groups, respectively; congenital malformations explained 36% and 23% in the LBW group and ≥2,500 g groups (2,500-3,499 g and ≥3,500 g groups combined), respectively. Central nervous system conditions explained 20% of deaths in childhood/adolescence in the VLBW group, with deaths from neoplasms and external conditions increasingly prevalent in the 1,500-2,499 g and ≥2,500 g birthweight groups. The study would have benefited had we had access to information on gestational age and maternal smoking, but since the former is highly correlated with birthweight and the latter with deprivation, we believe that our findings remain robust despite these shortcomings.

CONCLUSIONS

LBW is associated with infant and later child and adolescent mortality, with perinatal factors and congenital malformations explaining many of the deaths. By understanding and ameliorating the influences of upstream exposures such as maternal smoking and deprivation, later mortality can be decreased by reducing the delivery of vulnerable infants with LBW.

Trends in Survival and Incidence of Bronchopulmonary Dysplasia in Extremely Preterm Infants at 23-26 Weeks Gestation

The aim of this study was to investigate the relationship between survival and incidence of bronchopulmonary dysplasia (BPD) in extremely premature infants, and identify clinical factors responsible for this association. Medical records of 350 infants at 23-26 weeks gestation from 2000 to 2005 (period I, n = 137) and 2006 to 2010 (period II, n = 213) were retrospectively reviewed. The infants were stratified into 23-24 and 25-26 weeks gestation, and the survival, BPD incidence, and clinical characteristics were analyzed. BPD was defined as oxygen dependency at 36 weeks postmenstrual age. The overall survival rate was significantly improved in period II compared to period I (80.3% vs. 70.0%, respectively; P = 0.028), especially in infants at 23-24 weeks gestation (73.9% vs. 47.4%, respectively; P = 0.001). The BPD incidence in survivors during period II (55.0%) was significantly decreased compared to period I (67.7%; P = 0.042), especially at 25-26 weeks gestation (41.7% vs. 62.3%, respectively; P = 0.008). Significantly improved survival at 23-24 weeks gestation was associated with a higher antenatal steroid use and an improved 5-minute Apgar score. A significant decrease in BPD incidence at 25-26 weeks gestation was associated with early extubation, prolonged use of less invasive continuous positive airway pressure, and reduced supplemental oxygen. Improved perinatal and neonatal care can simultaneously lead to improved survival and decreased BPD incidence in extremely premature infants.

Why birthplace still matters for infants born before 32 weeks: Infant mortality associated with birth at 22-31 weeks' gestation in non-tertiary hospitals in Victoria over two decades

BACKGROUND

Very preterm infants born in non-tertiary hospitals ('outborn') are known to have higher mortality rates compared with infants 'inborn' in tertiary centres.

AIM

The aim of this study was to report changes over time in the incidence of outborn livebirths, 22-31 weeks and infant mortality rates for outborn compared with inborn births.

METHODS

We conducted a population-based cohort study of consecutive livebirths, 22-31 weeks' gestation in Victoria from 1990 to 2009. The relationship between birthplace, gestational age, birthweight, sex and infant mortality were analysed by logistic regression.

RESULTS

There were 13,760 livebirths, 22-31 weeks: 14% were outborn. The proportion of outborn livebirths fell from 19% in 1991 to a nadir of 9% in 1997, but climbed to 17% by 2009. At all times, outborns had higher mortality rates compared with inborns. The overall infant mortality rate was 250.6 per 1000 outborn compared with 113.3 per 1000 inborn livebirths (adjusted odds ratio (aOR) 2.76 (95% CI 2.32, 3.27, P < 0.001). There were no differences between outborn and inborn mortality risks for 22-week livebirths (OR 7.04, 95% CI 0.87, 56.8, P = 0.067), but there were at 23-27 weeks (aOR 3.16, 95% CI 2.52, 3.96, P < 0.001) and at 28-31 weeks (aOR 1.66, 95% CI 1.19, 2.31, P = 0.003). Over time, mortality rates fell for inborn 23-27 week infants. Mortality rates fell for outborn 23-27 week infants in 1990-2005, but rose in 2006-2009.

CONCLUSIONS

Outborn livebirths at 22-31 weeks' gestation occur too frequently and are associated with a significantly increased risk of mortality. Strategies to reduce outborn livebirths are required.

Changes in infant mortality among extremely preterm infants: US vital statistics data 1990 vs 2000 vs 2010

OBJECTIVE

Infant mortality among extremely preterm infants (22 to 28 weeks gestation) varies considerably by gestational age. The reduction in mortality over a 20-year period, when examined in gestational age week increments, may give a more precise estimate of progress or lack thereof in caring for these infants and provide information to better inform practitioners and parents of the risk of mortality among these small infants. The objective of this analysis is to examine infant mortality (birth to 365 days) by week of gestation for infants 22 to 28 weeks gestation comparing mortality rates, adjusting for maternal and infant birth characteristics, among US births for the years 1990, 2000 and 2010.

STUDY DESIGN

US vital statistics period-linked birth and infant death certificate files for the years 1990, 2000 and 2010 were used. Maternal and infant characteristics for births at 22 to 28 weeks were abstracted from the files. A trimming procedure was used to remove records that had birth weights that exceeded the interquartile range of birth weights for a given week of gestational age. Infant mortality rates were calculated, and adjusted odds ratios for mortality were generated using logistic regression models.

RESULT

A total of 15,593 live births, 22 to 28 weeks gestation were available for the year 1990; 17,095 for the year 2000; and 14,721 for the year 2010. Infant mortality rates ranged from 904 per 1000 live births at 22 weeks gestation in 1990, to 835 in 2000, to 866 in 2010. Across all gestational age groups there was an adjusted reduction in the odds ratio for mortality of ~50% from 1990 to the year 2000. However, between 2000 and 2010 there was no significant reduction in infant mortality except at 25 weeks gestation (adjusted odds ratio=0.81, 95% confidence interval=0.70, 0.93).

CONCLUSION

Despite a significant reduction in infant mortality among extremely preterm infants between the years 1990 and 2000, there has been little progress in reducing mortality between the years 2000 and 2010.

Neurodevelopmental outcome of extremely low birth weight infants at 24 months corrected age: a comparison between Griffiths and Bayley Scales

Background

The availability of accurate assessment tools for the early detection of infants at risk for adverse neurodevelopmental outcomes is a major issue. The purpose of this study is to compare the outcomes of the Bayley Scales (Bayley-II vs Bayley-III) in a cohort of extremely low birth weight infants at 24 months corrected age, to define which edition shows the highest agreement with the Griffiths Mental Development Scales Revised.

Methods

We performed a single-centre cohort study. We prospectively enrolled infants with a birth weight of 401–1000 g and/or gestational age < 28 weeks. Exclusion criteria were the presence of neurosensory disabilities and/or genetic abnormalities. Infants underwent neurodevelopmental evaluation at 24 months corrected age using the Griffiths and either the Bayley-II (birth years 2003–2006) or the Bayley-III (birth years 2007–2010).

Results

A total of 194 infants were enrolled. Concordance was excellent between the Griffiths and the Bayley-III composite scores for both cognitive language and motor abilities (weighted K = 0.80 and 0.81, respectively) but poorer for the Bayley-II (weighted K = 0.63 and 0.50, respectively). The Youden’s Index revealed higher values for the Bayley-III than for the Bayley-II (75.9 vs 69.6 %). Compared with the Griffiths, the Bayley-III found 3 % fewer infants as being severely impaired in cognitive-language abilities and 7.8 % fewer infants as being mildly impaired in motor skills while the Bayley-II showed, compared with the Griffiths, higher rates of severely impaired children both for cognitive-language and motor abilities (14.1 and 15.3 % more infants respectively).

Discussion

Our study suggests that the Bayley-III, although having a higher agreement with the Griffiths compared to the Bayley-II, slightly tends to underestimate neurodevelopmental impairment compared with the Griffiths, whereas the Bayley-II tends to overestimate it.

Conclusions

On the basis of these findings, we recommend the use of multiple measures to assess neurodevelopmental outcomes of extremely low birth weight infants at 24 months.

PPREMO: a prospective cohort study of preterm infant brain structure and function to predict neurodevelopmental outcome

BACKGROUND

More than 50 percent of all infants born very preterm will experience significant motor and cognitive impairment. Provision of early intervention is dependent upon accurate, early identification of infants at risk of adverse outcomes. Magnetic resonance imaging at term equivalent age combined with General Movements assessment at 12 weeks corrected age is currently the most accurate method for early prediction of cerebral palsy at 12 months corrected age. To date no studies have compared the use of earlier magnetic resonance imaging combined with neuromotor and neurobehavioural assessments (at 30 weeks postmenstrual age) to predict later motor and neurodevelopmental outcomes including cerebral palsy (at 12-24 months corrected age). This study aims to investigate i) the relationship between earlier brain imaging and neuromotor/neurobehavioural assessments at 30 and 40 weeks postmenstrual age, and ii) their ability to predict motor and neurodevelopmental outcomes at 3 and 12 months corrected age.

METHODS/DESIGN

This prospective cohort study will recruit 80 preterm infants born ≤ 30 week's gestation and a reference group of 20 healthy term born infants from the Royal Brisbane & Women's Hospital in Brisbane, Australia. Infants will undergo brain magnetic resonance imaging at approximately 30 and 40 weeks postmenstrual age to develop our understanding of very early brain structure at 30 weeks and maturation that occurs between 30 and 40 weeks postmenstrual age. A combination of neurological (Hammersmith Neonatal Neurologic Examination), neuromotor (General Movements, Test of Infant Motor Performance), neurobehavioural (NICU Network Neurobehavioural Scale, Premie-Neuro) and visual assessments will be performed at 30 and 40 weeks postmenstrual age to improve our understanding of the relationship between brain structure and function. These data will be compared to motor assessments at 12 weeks corrected age and motor and neurodevelopmental outcomes at 12 months corrected age (neurological assessment by paediatrician, Bayley scales of Infant and Toddler Development, Alberta Infant Motor Scale, Neurosensory Motor Developmental Assessment) to differentiate atypical development (including cerebral palsy and/or motor delay).

DISCUSSION

Earlier identification of those very preterm infants at risk of adverse neurodevelopmental and motor outcomes provides an additional period for intervention to optimise outcomes.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12613000280707. Registered 8 March 2013.

Motor performance, postural stability and behaviour of non-disabled extremely preterm or extremely low birth weight children at four to five years of age

BACKGROUND

Extremely preterm or extremely low birth weight (ELBW) children who are non-disabled and otherwise healthy are at risk of neurodevelopmental impairments. Further understanding of these impairments is needed before commencement of formal education to optimise participation levels at a critical time point for these children.

AIMS

To explore motor co-ordination, postural stability, limb strength and behaviour of non-disabled four to five year old children with a history of extreme prematurity or ELBW.

STUDY DESIGN

Prospective-descriptive-cohort-study.

SUBJECTS

50 children born at less than 28 weeks gestation or who had a birth weight less than 1000g with minimal/mild motor impairments and no significant neurological/cognitive impairments.

OUTCOME MEASURES

Movement Assessment Battery for Children second-edition (MABC-2), single leg stance test (SLS), lateral reach test, standing long jump test and Child Behaviour Checklist for preschool children (CBCL).

RESULTS

The mean percentile rank of the extremely preterm or ELBW sample on MABC-2 was 31% (SD 23%). SLS right (mean ± SD; 4.6 ± 2.5s) and lateral reach to the right (10.0 ± 3.9 cm) were slightly stronger than SLS left (4.4 ± 3.3s) and lateral reach left (9.9 ± 3.5 cm). The average for standing long jump was 71.6 cm (SD 21.0 cm). All participants were classified as 'normal' on CBCL syndrome scale scores, internalizing and externalizing syndrome T scores and total problem T score.

CONCLUSIONS

This sample of non-disabled extremely preterm or ELBW children performed in the lower range of normal. These children continue to be at risk of impairments, therefore, ongoing monitoring and tailored intervention may optimise development.

Morbidity and mortality in hospitalised neonates in central Vietnam

AIM

This study explored neonatal morbidity and mortality in hospitalised patients in central Vietnam and risk factors associated with mortality.

METHODS

We conducted a prospective cohort study of all newborn infants (<28 days) hospitalised in a neonatal unit over a 1-year period and followed until discharge. The main outcome measures were case fatality rate and the rate of different clinical diagnoses.

RESULTS

There were 2555 admissions during the study period. The leading primary causes of admissions were infections (41%), haematological problems such as jaundice (23%) and prematurity and its complications (18%). The overall case fatality rate was 8.6%, and it was 59% among very low-birthweight (<1500 g) neonates. Mortality was inversely associated with birthweight and gestational age. Of the 220 deaths, 57% occurred within the first 7 days of life. Although the causes of death were often multifactorial, the leading primary causes were infections (32%), prematurity and its complications (25%), birth defects (24%) and birth asphyxia (6%). Risk factors associated with death were being outborn, early gestational age, small for gestational age, confirmed sepsis and birth defects.

CONCLUSION

Mortality rates were high among hospitalised neonates in central Vietnam, and this paper suggests interventions that might improve outcomes.

Social variables predict gains in cognitive scores across the preschool years in children with birth weights 500 to 1250 grams

OBJECTIVE

To determine the extent that social variables influence cognitive development of very low birth weight (VLBW) infants across the preschool years.

STUDY DESIGN

Participants were VLBW (500-1250 g) children enrolled in the Caffeine for Apnea of Prematurity randomized trial between 1999 and 2004. We investigated the relationships between 4 potential social advantages: higher maternal education, higher paternal education, caregiver employment, and 2 biologic parents in the same home--and gain in cognitive scores. Cognitive assessments were performed at the corrected ages of 18 months (Mental Development Index score on the Bayley Scales of Infant Development II) and 5 years (Full Scale IQ on the Wechsler Preschool and Primary Scale of Intelligence III). Cognitive gain was computed by subtracting each individual 18-month Mental Development Index score from the corresponding Full Scale IQ at 5 years.

RESULTS

Data were available for 1347 children. Mean (SD) cognitive scores were 90.8 (15.7) at 18 months and 98.9 (14.5) at 5 years. Multivariable regression showed that higher maternal education, higher paternal education, and caregiver employment had independent and additive effects of similar size on cognitive gain (P < .001); the mean cognitive gain between 18 months and 5 years increased by 3.6 points in the presence of each of these advantages. When all 3 were present, cognitive scores improved on average by 10.9 points compared with children without any of these advantages.

CONCLUSION

In VLBW children, a count of 3 social advantages strongly predicts gains in cognitive scores across the preschool years.

Growth restriction, leptin, and the programming of adult behavior in mice

Prematurity and neonatal growth restriction (GR) are risk factors for autism and attention deficit hyperactivity disorder (ADHD). Leptin production is suppressed during periods of undernutrition, and we have shown that isolated neonatal leptin deficiency leads to adult hyperactivity while neonatal leptin supplementation normalizes the brain morphology of GR mice. We hypothesized that neonatal leptin would prevent the development of GR-associated behavioral abnormalities. From postnatal day 4-14, C57BL/6 mice were randomized to daily injections of saline or leptin (80ng/g), and GR was identified by a weanling weight below the tenth percentile. The behavioral phenotypes of GR and control mice were assessed beginning at 4 months. Within the tripartite chamber, GR mice had significantly impaired social interaction. Baseline escape times from the Barnes maze were faster for GR mice (65+/-6s vs 87+/-7s for controls, p<0.05), but GR mice exhibited regression in their escape times on days 2 and 3 (56% regressed vs 22% of control saline mice, p<0.05). Compared to controls, GR mice entered the open arms of the elevated plus maze more often and stayed there longer (72+/-10s vs 36+/-5s, p<0.01). Neonatal leptin supplementation normalized the behavior of GR mice across all behavioral assays. In conclusion, GR alters the social interactions, learning and activity of mice, and supplementation with the neurotrophic hormone leptin mitigates these effects. We speculate neonatal leptin deficiency may contribute to the adverse neurodevelopmental outcomes associated with postnatal growth restriction, and postnatal leptin therapy may be protective.

Resuscitation of neonates at 23 weeks' gestational age: a cost-effectiveness analysis

OBJECTIVE

Resuscitation of infants at 23 weeks' gestation remains controversial; clinical practices vary. We sought to investigate the cost effectiveness of resuscitation of infants born 23 0/7-23 6/7 weeks' gestation.

DESIGN

Decision-analytic modeling comparing universal and selective resuscitation to non-resuscitation for 5176 live births at 23 weeks in a theoretic U.S. cohort. Estimates of death (77%) and disability (64-86%) were taken from the literature. Maternal and combined maternal-neonatal utilities were applied to discounted life expectancy to generate QALYs. Incremental cost-effectiveness ratios were calculated, discounting costs and QALYs. Main outcomes included number of survivors, their outcome status and incremental cost-effectiveness ratios for the three strategies. A cost-effectiveness threshold of $100 000/QALY was utilized.

RESULTS

Universal resuscitation would save 1059 infants: 138 severely disabled, 413 moderately impaired and 508 without significant sequelae. Selective resuscitation would save 717 infants: 93 severely disabled, 279 moderately impaired and 343 without significant sequelae. For mothers, non-resuscitation is less expensive ($19.9 million) and more effective (127 844 mQALYs) than universal resuscitation ($1.2 billion; 126 574 mQALYs) or selective resuscitation ($845 million; 125 966 mQALYs). For neonates, both universal and selective resuscitation were cost-effective, resulting in 22 256 and 15 134 nQALYS, respectively, versus 247 nQALYs for non-resuscitation. In sensitivity analyses, universal resuscitation was cost-effective from a maternal perspective only at utilities for neonatal death <0.42. When analyzed from a maternal-neonatal perspective, universal resuscitation was cost-effective when the probability of neonatal death was <0.95.

CONCLUSIONS

Over wide ranges of probabilities for survival and disability, universal and selective resuscitation strategies were not cost-effective from a maternal perspective. Both strategies were cost-effective from a maternal-neonatal perspective. This study offers a metric for counseling and decision-making for extreme prematurity. Our results could support a more permissive response to parental requests for aggressive intervention at 23 weeks' gestation.

Long-term outcome for the tiniest or most immature babies: survival rates

This article focuses on the survival rates of the most immature babies considered viable from around the world. It discusses the various factors in terms of definition, inclusion criteria and policy which can result in marked differences in the apparent rates of delivery (all births), live birth, admission to neonatal intensive care and ultimately survival seen between otherwise similar countries, different regions of the same country, and even adjacent hospitals. Such variation in approach can result in major differences in reported survival and consequentially have large effects on apparent rates of adverse long-term outcome.

Improving preterm infants' immunisation status: a follow-up audit

AIM

Preterm infants are at increased risk of vaccine preventable diseases. An audit in 2007 identified suboptimal immunisation status of preterm infants. The aim of this study was to complete the 'audit loop', reviewing preterm infants' immunisation status at a single tertiary paediatric hospital.

METHODS

A retrospective follow-up immunisation audit was conducted at The Royal Children's Hospital, Melbourne, neonatal unit. The 'audit loop' included a preterm infants' reminder sticker and feedback of the original audit findings to Royal Children's Hospital health-care professionals. Immunisation status was determined using the Australian Childhood Immunisation Register record for all admitted preterm infants born <32 weeks gestation (July 2008-June 2009).

RESULTS

Conducted in March 2011, the median age of participants (n = 57) was 2.5 years (range 1.7-3.1 years). Forty-four per cent (25/57) had a history of chronic lung disease, 86% (49/57) were <1500 g and 42% (24/57) <28 weeks gestation. The majority (96% (55/57)) were up to date with routine immunisations at 12 months of age. There was a 2.4-fold increase, compared with the original audit, for receipt of the additional recommended hepatitis B vaccine at 12 months of age, as well as influenza vaccine in infants with chronic lung disease.

CONCLUSION

This study showed that a simple reminder combined with education strategies can improve vaccine delivery in special risk groups such as preterm infants.

Respiratory outcomes for the tiniest or most immature infants

Extremely low birth weight (<1000 g birth weight) or extremely preterm (<28 weeks of gestation) infants are surviving in greater numbers as neonatal care advances. Many of these survivors, especially those who develop bronchopulmonary dysplasia, have more respiratory ill health in the first years after discharge home, reduced respiratory function and impaired exercise capacity throughout childhood and into adulthood compared with term-born controls. It is important to establish the long-term respiratory outcomes for the tiniest or most immature survivors as they grow older, since they may contribute disproportionately to rates of chronic obstructive pulmonary disease and respiratory ill-health in adulthood.

Long-term growth and general health for the tiniest or most immature infants

Given the improving survival rates of extremely preterm (EP, gestational age <28 weeks) infants, there is a need to understand their general growth and health outcomes not only in childhood, but also into adulthood. EP children are shorter and lighter compared with term children at term-equivalent age; with time, the weight disadvantage diminishes but the height disadvantage remains relatively unchanged. EP children and young adults also have higher rates of reported health concerns, medical conditions and visual impairment. Hospital readmissions are higher in early childhood, mostly attributed to respiratory illness. Individuals born EP have reduced bone health and are at increased risk for metabolic disorders. Increased rates of conditions such as diabetes or pathological fractures are not reported in the literature, although follow-up studies so far have only tracked EP individuals into young adulthood. Consequently, health care utilization and costs are increased in EP children and young adults. A thorough knowledge of the health risks related to EP birth is essential in planning surveillance and intervention strategies to optimize their health and wellbeing. Despite the increased risk of health problems, EP young adults generally report their quality of life to be similar to that reported in their term counterparts.

Invasive procedures in preterm children: brain and cognitive development at school age

BACKGROUND

Very preterm infants (born 24-32 weeks' gestation) undergo numerous invasive procedures during neonatal care. Repeated skin-breaking procedures in rodents cause neuronal cell death, and in human preterm neonates higher numbers of invasive procedures from birth to term-equivalent age are associated with abnormal brain development, even after controlling for other clinical risk factors. It is unknown whether higher numbers of invasive procedures are associated with long-term alterations in brain microstructure and cognitive outcome at school age in children born very preterm.

METHODS

Fifty children born very preterm underwent MRI and cognitive testing at median age 7.6 years (interquartile range, 7.5-7.7). T1- and T2-weighted images were assessed for the severity of brain injury. Magnetic resonance diffusion tensor sequences were used to measure fractional anisotropy (FA), an index of white matter (WM) maturation, from 7 anatomically defined WM regions. Child cognition was assessed using the Wechsler Intelligence Scale for Children-IV. Multivariate modeling was used to examine relationships between invasive procedures, brain microstructure, and cognition, adjusting for clinical confounders (eg, infection, ventilation, brain injury).

RESULTS

Greater numbers of invasive procedures were associated with lower FA values of the WM at age 7 years (P = .01). The interaction between the number of procedures and FA was associated with IQ (P = .02), such that greater numbers of invasive procedures and lower FA of the superior WM were related to lower IQ.

CONCLUSIONS

Invasive procedures during neonatal care contribute to long-term abnormalities in WM microstructure and lower IQ.

Beyond the borderline: outcomes for inborn infants born at ≤500 grams

AIM

To report survival, morbidity and neurodevelopmental outcome in a cohort of extremely low birthweight infants.

METHODS

Retrospective cohort study of all inborn infants born alive with birthweights ≤500 g ≥22 weeks gestation at Women's and Children's Hospital, Adelaide, Australia, over a 6-year period (2005-2010). Outcome data including standardised medical and psychological assessments at 12 and 36 months corrected age were collated from follow-up.

RESULTS

A total of 36 eligible infants were born over the study period (mean gestational age (GA) 24.4 (range 22.0-30.0) weeks; birthweight 443 (330-500) grams). Twenty-six of the 36 (72%) infants were small for gestational age (SGA).Ten of the 36 infants received compassionate care and died in the delivery or operating room. Twenty-six of the 36 infants were admitted to the neonatal intensive care unit (NICU), of whom 12 (46%) died during their admission. At age 12 months corrected, 2/14 (14%) of survivors had none/minimal, 4/14 (29%) had mild and 8/14 (57%) had moderate/severe neurodevelopmental disability. Overall, the survival rate was 39%, and survival without neurodevelopmental disability was 6%. Only 1/10 appropriate-for-gestational-age (AGA) infants survived to discharge (and had severe disability), whereas 13/26 (50%) of all SGA infants in the study survived to discharge. Of all infants admitted to the NICU, 11/26 (42%) survived without severe neurodevelopmental disability at latest follow-up.

CONCLUSIONS

There was a high risk of death or impairment in this cohort of infants. Survival was rare for AGA infants weighing ≤500 g at birth. Our study provides an evidence base to assist counselling and decision-making.

Outcomes following periviable birth

This review is presented in three segments: (1) important background concepts, (2) recent reports from regional geographically defined cohorts, and (3) prognosis research from the National Institutes of Health Neonatal Research Network. Extending the use of intensive care to newborns of lower gestational ages will unavoidably result in a higher proportion and a higher absolute number of survivors with morbidity, unless other changes in practice offset the increased risk associated with decreasing gestational age. In geographically defined cohort studies, the proportion of periviable newborns delivered in perinatal centers and the practices around foregoing and withdrawing intensive care are two important determinants of outcomes following periviable birth. It is much easier to quantify the effect of the former than the latter. Decisions regarding comfort care vs. intensive are frequently based on gestational age as the sole predictor variable, although multiple factors can be readily used to more accurately assess the benefits and burdens of intensive care and facilitate better informed parental counseling and decision making.

Intraventricular hemorrhage and neurodevelopmental outcomes in extreme preterm infants

OBJECTIVE

Not many large studies have reported the true impact of lower-grade intraventricular hemorrhages in preterm infants. We studied the neurodevelopmental outcomes of extremely preterm infants in relation to the severity of intraventricular hemorrhage.

METHODS

A regional cohort study of infants born at 23 to 28 weeks' gestation and admitted to a NICU between 1998 and 2004. Primary outcome measure was moderate to severe neurosensory impairment at 2 to 3 years' corrected age defined as developmental delay (developmental quotient >2 SD below the mean), cerebral palsy, bilateral deafness, or bilateral blindness.

RESULTS

Of the 1472 survivors assessed, infants with grade III-IV intraventricular hemorrhage (IVH; n = 93) had higher rates of developmental delay (17.5%), cerebral palsy (30%), deafness (8.6%), and blindness (2.2%). Grade I-II IVH infants (n = 336) also had increased rates of neurosensory impairment (22% vs 12.1%), developmental delay (7.8% vs 3.4%), cerebral palsy (10.4% vs 6.5%), and deafness (6.0% vs 2.3%) compared with the no IVH group (n = 1043). After exclusion of 40 infants with late ultrasound findings (periventricular leukomalacia, porencephaly, ventricular enlargement), isolated grade I-II IVH (n = 296) had increased rates of moderate-severe neurosensory impairment (18.6% vs 12.1%). Isolated grade I-II IVH was also independently associated with a higher risk of neurosensory impairment (adjusted odds ratio 1.73, 95% confidence interval 1.22-2.46).

CONCLUSIONS

Grade I-II IVH, even with no documented white matter injury or other late ultrasound abnormalities, is associated with adverse neurodevelopmental outcomes in extremely preterm infants.

Preventing academic difficulties in preterm children: a randomised controlled trial of an adaptive working memory training intervention - IMPRINT study

Background

Very preterm children exhibit difficulties in working memory, a key cognitive ability vital to learning information and the development of academic skills. Previous research suggests that an adaptive working memory training intervention (Cogmed) may improve working memory and other cognitive and behavioural domains, although further randomised controlled trials employing long-term outcomes are needed, and with populations at risk for working memory deficits, such as children born preterm.

In a cohort of extremely preterm (<28 weeks’ gestation)/extremely low birthweight (<1000 g) 7-year-olds, we will assess the effectiveness of Cogmed in improving academic functioning 2 years’ post-intervention. Secondary objectives are to assess the effectiveness of Cogmed in improving working memory and attention 2 weeks’, 12 months’ and 24 months’ post-intervention, and to investigate training related neuroplasticity in working memory neural networks 2 weeks’ post-intervention.

Methods/Design

This double-blind, placebo-controlled, randomised controlled trial aims to recruit 126 extremely preterm/extremely low birthweight 7-year-old children. Children attending mainstream school without major intellectual, sensory or physical impairments will be eligible. Participating children will undergo an extensive baseline cognitive assessment before being randomised to either an adaptive or placebo (non-adaptive) version of Cogmed. Cogmed is a computerised working memory training program consisting of 25 sessions completed over a 5 to 7 week period. Each training session takes approximately 35 minutes and will be completed in the child’s home. Structural, diffusion and functional Magnetic Resonance Imaging, which is optional for participants, will be completed prior to and 2 weeks following the training period. Follow-up assessments focusing on academic skills (primary outcome), working memory and attention (secondary outcomes) will be conducted at 2 weeks’, 12 months’ and 24 months’ post-intervention.

Discussion

To our knowledge, this study will be the first randomised controlled trial to (a) assess the effectiveness of Cogmed in school-aged extremely preterm/extremely low birthweight children, while incorporating advanced imaging techniques to investigate neural changes associated with adaptive working memory training, and (b) employ long-term follow-up to assess the potential benefit of improved working memory on academic functioning. If effective, Cogmed would serve as a valuable, available intervention for improving developmental outcomes for this population.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12612000124831.