Urine Desmosine as a Novel Biomarker for Bronchopulmonary Dysplasia and Postprematurity Respiratory Disease in Extremely Preterm or Low Birth Weight Infants.

OBJECTIVE: This study aimed to evaluate whether elevated urine desmosine levels at 3 weeks of age were associated with severe radiological findings, bronchopulmonary dysplasia (BPD), and post-prematurity respiratory disease (PRD) in extremely preterm (EP) or extremely low birth weight (ELBW) infants. STUDY DESIGN: This study recruited 37 EP (22-27 completed weeks) or ELBW (<1,000 g) infants. Urine was collected between 21 and 28 postnatal days, and desmosine was measured using an enzyme-linked immunosorbent assay kit; the urine creatinine level was also measured. Bubbly/cystic lungs were characterized by emphysematous chest X-rays on postnatal day 28. Furthermore, provision of supplemental oxygen or positive-pressure respiratory support at 40 weeks' postmenstrual age defined BPD, and increased medical utilization at 18 months of corrected age defined PRD. The desmosine/creatinine threshold was determined by receiver operating characteristic analysis. The adjusted risk and 95% confidence interval (CI) for elevated urine desmosine/creatinine levels were estimated by logistic regression analysis. RESULTS: Elevated urine desmosine/creatinine levels higher than the threshold were significantly associated with bubbly/cystic lungs (8/13 [61.5%] vs. 2/24 [8.3%], p = 0.001), BPD (10/13 [76.9%] vs. 8/24 [33.3%], p = 0.02), and PRD (6/13 [46.2%] vs. 2/24 [8.3%], p = 0.01). After adjusting for gestational age, birth weight, and sex, the urine desmosine/creatinine levels were significantly higher in those who were highly at risk of bubbly/cystic lungs (odds ratio [OR], 13.2; 95% CI, 1.67-105) and PRD (OR, 13.8; 95% CI, 1.31-144). CONCLUSION: Elevated urine desmosine/creatinine levels on the third postnatal week were associated with bubbly/cystic lungs on day 28 and PRD at 18 months of corrected age in EP or ELBW infants. KEY POINTS: · Urine desmosine was prospectively measured in 3-week-old EP/ELBW infants.. · Elevated urine desmosine levels were associated with emphysematous radiological findings on day 28, PRD at 18 months of corrected age.. · Urine desmosine may be a promising biomarker indicating lung damage in EP/ELBW infants..

A Retrospective Cohort Study on Mortality and Neurodevelopmental Outcomes of Preterm Very Low Birth Weight Infants Born to Mothers with Hypertensive Disorders of Pregnancy.

OBJECTIVE: We examined the effects of maternal hypertensive disorders of pregnancy (HDP) on the mortality and neurodevelopmental outcomes in preterm very low birth weight (VLBW) infants (BW ≤1,500 g) based on their intrauterine growth status and gestational age (GA). STUDY DESIGN: We included singleton VLBW infants born at <32 weeks' gestation registered in the Neonatal Research Network Japan database. The composite outcomes including death, cerebral palsy (CP), and developmental delay (DD) at 3 years of age were retrospectively compared among three groups: appropriate for GA (AGA) infants of mothers with and without HDP (H-AGA and N-AGA) and small for GA (SGA) infants of mothers with HDP (H-SGA). The adjusted odds ratios (AOR) and 95% confidence intervals (CI) stratified by the groups of every two gestational weeks were calculated after adjusting for the center, year of birth, sex, maternal age, maternal diabetes, antenatal steroid use, clinical chorioamnionitis, premature rupture of membranes, non-life-threatening congenital anomalies, and GA. RESULTS: Of 19,323 eligible infants, outcomes were evaluated in 10,192 infants: 683 were H-AGA, 1,719 were H-SGA, and 7,790 were N-AGA. Between H-AGA and N-AGA, no significant difference was observed in the risk for death, CP, or DD in any GA groups. H-AGA had a lower risk for death, CP, or DD than H-SGA in the 24 to 25 weeks group (AOR: 0.434, 95% CI: 0.202-0.930). The odds for death, CP, or DD of H-SGA against N-AGA were found to be higher in the 24 to 25 weeks (AOR: 2.558, 95% CI: 1.558-3.272) and 26 to 27 weeks (AOR: 1.898, 95% CI: 1.427-2.526) groups, but lower in the 30 to 31 weeks group (AOR: 0.518, 95% CI: 0.335-0.800). CONCLUSION: There was a lack of follow-up data; however, the outcomes of liveborn preterm VLBW infants of mothers with HDP depended on their intrauterine growth status and GA at birth. KEY POINTS: · The effects of HDP on preterm low birth weight infants need to be further examined.. · The outcomes were not different between AGA infants with and without maternal HDP.. · The outcomes of SGA infants with maternal HDP were dependent on their GA..

Short- and Long-Term Outcomes of Extremely Preterm Infants in Japan According to Outborn/Inborn Birth Status.

OBJECTIVES: Outborn (born outside tertiary centers) infants, especially extremely preterm infants, are at an increased risk of mortality and morbidity in comparison to inborn (born in tertiary centers) infants. Extremely preterm infants require not only skilled neonatal healthcare providers but also highly specialized equipment and environment surroundings. Maternal transport at an appropriate timing must be done to avoid the delivery of extremely preterm infants in a facility without the necessary capabilities. Cases of unexpected deliveries at birth centers or level I maternity hospitals need to be attended emergently. We compared the differences in short- and long-term outcomes between outborn and inborn infants to improve our regional perinatal system. DESIGN: Retrospective cohort study. SETTING: Neonatal Research Network of Japan database. PATIENTS: Extremely preterm infants (gestational age between 22 + 0 and 27 + 6 wk) in the Neonatal Research Network of Japan database between 2003 and 2011. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 12,164 extremely preterm infants, who were divided into outborn (n = 785, 6.5%) and inborn (n = 11,379, 93.5%) groups, were analyzed. Significant differences were observed in demographic and clinical factors between the two groups. Outborn infants had higher short-term odds of severe intraventricular hemorrhage (adjusted odds ratio, 1.49; 95% CI, 1.11-2.00; p < 0.01), necrotizing enterocolitis (adjusted odds ratio, 1.49; 95% CI, 1.11-2.00; p < 0.01), and focal intestinal perforation (adjusted odds ratio, 1.58; 95% CI, 1.09-2.30; p = 0.02). There were no significant differences in long-term outcomes between the two groups, except in the rate of cognitive impairment (adjusted odds ratio, 1.49; 95% CI, 1.01-2.20; p = 0.04). CONCLUSIONS: The frequency of severe intraventricular hemorrhage, necrotizing enterocolitis or focal intestinal perforation, and cognitive impairment was significantly higher in outborn infants. Thus, outborn/inborn birth status may play a role in short- and long-term outcomes of extremely preterm infants. However, more data and evaluation of improvement in the current perinatal environment are needed.

Bubbly and cystic appearance in chronic lung disease: Is this diagnosed as Wilson-Mikity syndrome?

Wilson-Mikity syndrome (WMS) was first reported in 1960 by Wilson and Mikity. They described preterm infants who developed areas of cystic emphysema in the first month of life with subsequent progression to chronic lung disease (CLD) of infancy, although these infants did not exhibit early respiratory distress, such as respiratory distress syndrome (RDS). This condition was widely accepted over the next 20 years, but WMS is now rarely mentioned and is commonly considered an anachronism. In Japan, CLD is classified into six types according to the presence of RDS and/or intrauterine inflammation and appearance on chest X-ray. One type of CLD (type III, which accounts for 13.5% of all CLD) is defined as history of intrauterine inflammation and the typical bubbly and cystic appearance on chest X-ray described in the original report of WMS. There is insufficient evidence to determine whether WMS exists or whether WMS is relatively common only in Japan and not in other countries. It is important, however, to distinguish this type of CLD from other types because the strategy for the prevention or treatment of CLD should be different according to its origin, cause, and risk factors.

The Effects of Antenatal Corticosteroids on Short- and Long-Term Outcomes in Small-for-Gestational-Age Infants.

AIM: To evaluate the effect of antenatal corticosteroids (ANS) on short- and long-term outcomes in small-for-gestational age (SGA) infants. METHODS: A retrospective database analysis was performed. A total of 1,931 single infants (birth weight <1,500 g) born at a gestational age between 22 weeks and 33 weeks 6 days who were determined to be SGA registered in the Neonatal Research Network Database in Japan between 2003 and 2007 were evaluated for short-term outcome and long-term outcome. RESULTS: ANS was administered to a total of 719 infants (37%) in the short-term outcome evaluation group and 344 infants (36%) in the long-term outcome evaluation group. There were no significant differences between the ANS group and the no-ANS group for primary short-term outcome (adjusted odds ratio (OR) 0.73; 95% confidence interval (CI) 0.45-1.20; P-value 0.22) or primary long-term outcome (adjusted OR 0.69; 95% CI 0.40-1.17; P-value 0.17). CONCLUSIONS: Our results show that ANS does not affect short- or long-term outcome in SGA infants when the birth weight is less than 1500 g. This study strongly suggests that administration of ANS resulted in few benefits for preterm FGR fetuses.

Long-term alpha-tocopherol supplements may improve mental development in extremely low birthweight infants.

AIM: Methods to improve the mental development of extremely low birthweight (ELBW) children are currently lacking. We assessed the effects of long-term supplementation of alpha-tocopherol on the neurological development of 259 school-aged ELBW children. METHODS: Extremely low birthweight participants were divided into three groups: group A with no alpha-tocopherol supplementation (n = 121); group B with the supplementation for <6 months (n = 104) and group C with the supplementation for more than 6 months (n = 34). We analysed the participants' data at birth and between the ages of one-and-a-half to 8 years and evaluated potential factors associated with intellectual disabilities. RESULTS: Children from group C had the best outcome. The groups' mean gestational weeks and mean ventilator days were as follows: 27.5 weeks, 16.1 days (group A); 25.7 weeks, 41.7 days (group B); and 25.1 weeks, 75.5 days (group C). Multivariate regression analysis revealed that the odds ratios for impaired mental development at 8 years were 1.5 in group B and 0.19 (p = 0.017) in group C, compared with 1.0 in group A. The association between the duration of alpha-tocopherol administration and performance intelligence quotient (IQ) was dose dependent (p = 0.03). CONCLUSION: Long-term supplementation of alpha-tocopherol appeared to improve mental development, in particular, performance IQ, in school-aged ELBW children.

Patent ductus arteriosus management and outcomes in Japan and Canada: comparison of proactive and selective approaches.

OBJECTIVE: The aim of this study is to compare patent ductus arteriosus (PDA) management strategies and outcomes between the Neonatal Research Network of Japan (NRNJ) with proactive functional echocardiography and the Canadian Neonatal Network (CNN) with selective conventional echocardiography practice. STUDY DESIGN: Retrospective analyses examined very low-birth-weight infants admitted to the NRNJ or CNN in 2006 to 2008. Multivariable logistic regression analyses compared a composite outcome indicating a mortality or major morbidity (severe intraventricular hemorrhage, periventricular leukomalacia, severe retinopathy of prematurity, bronchopulmonary dysplasia, or necrotizing enterocolitis) between networks, according to PDA diagnosis and treatment, and tested the association between PDA treatment and the composite outcome within networks. RESULTS: PDA treatment (NRNJ:CNN) with conservative management (8%:16%), indomethacin only (77%:59%), ligation only (1%:13%), or indomethacin and ligation (14%:13%) varied significantly between networks. The composite outcome was lower in NRNJ versus CNN only among infants with PDA (odds ratio: 0.70; 95% confidence interval: 0.62-0.80). Surgical ligation was associated with higher composite outcome only in CNN (odds ratio: 1.79; 95% confidence interval: 1.40-2.28). CONCLUSION: Lower composite mortality/morbidity outcome in Japan versus Canada only among infants with PDA, and association of surgical ligation with higher mortality/morbidity only in Canada, suggest differential PDA management and ligation processes contribute to outcome variation.

Long-term outcomes of antenatal corticosteroids treatment in very preterm infants after chorioamnionitis.

PURPOSE: To evaluate the effect of antenatal corticosteroids (AC) therapy on short- and long-term outcomes among very low birth weight preterm infants after histologic chorioamnionitis (HCA). METHODS: We performed a retrospective analysis of 5240 single very low birth weight (VLBW) infants born at 22 + 0 and 33 + 6 weeks of gestation between 2003 and 2007, who registered to the Neonatal Research Network Japan. The effects of AC therapy on mortality, neurodevelopmental outcomes at 3 years of age and neonatal morbidities were analyzed in the groups with or without HCA using logistic regression analysis. RESULTS: In the study subjects, 840 were with HCA, 2734 were without HCA, and 1666 were excluded without data for HCA. AC therapy was significantly associated with decreasing mortality before 3 years of age; [0.52 (0.32-0.86)], [odds ratio (95 % confidence intervals]. There were no differences between the two groups regarding neurodevelopmental outcomes, including cerebral palsy [0.90 (0.41-1.99)], development quotient <70 [0.93 (0.48-1.81)], visual impairment [0.46 (0.04-5.18)], and severe hearing impairment [4.00 (0.30-53.4)] in the group with HCA as well as without HCA. Regarding neonatal morbidities, AC therapy was associated with a lower incidence of respiratory distress syndrome [0.67 (0.50-0.91)], sepsis [0.62 (0.41-0.94)], late-onset adrenal insufficiency [0.62 (0.39-0.98)] and an increased incidence of chronic lung disease [1.62 (1.18-2.24)] in the group with HCA. In the group without HCA, AC therapy was associated with decreasing respiratory distress syndrome [0.60 (0.43-0.84)] and increasing chronic lung disease [1.34 (1.11-1.62)]. CONCLUSION: AC therapy is significantly associated with reduced mortality before 3 years of age in VLBW infants with HCA, but not with neurodevelopmental outcomes, which was same as the results found in infants without HCA. AC therapy is recommended for women with suspected chorioamnionitis, as well as those without chorioamnionitis.

The International Network for Evaluating Outcomes of very low birth weight, very preterm neonates (iNeo): a protocol for collaborative comparisons of international health services for quality improvement in neonatal care.

BACKGROUND: The International Network for Evaluating Outcomes in Neonates (iNeo) is a collaboration of population-based national neonatal networks including Australia and New Zealand, Canada, Israel, Japan, Spain, Sweden, Switzerland, and the UK. The aim of iNeo is to provide a platform for comparative evaluation of outcomes of very preterm and very low birth weight neonates at the national, site, and individual level to generate evidence for improvement of outcomes in these infants. METHODS/DESIGN: Individual-level data from each iNeo network will be used for comparative analysis of neonatal outcomes between networks. Variations in outcomes will be identified and disseminated to generate hypotheses regarding factors impacting outcome variation. Detailed information on physical and environmental factors, human and resource factors, and processes of care will be collected from network sites, and tested for association with neonatal outcomes. Subsequently, changes in identified practices that may influence the variations in outcomes will be implemented and evaluated using quality improvement methods. DISCUSSION: The evidence obtained using the iNeo platform will enable clinical teams from member networks to identify, implement, and evaluate practice and service provision changes aimed at improving the care and outcomes of very low birth weight and very preterm infants within their respective countries. The knowledge generated will be available worldwide with a likely global impact.

The effects of antenatal corticosteroids therapy on very preterm infants after chorioamnionitis.

PURPOSE: To evaluate the effectiveness of antenatal corticosteroids (AC) therapy on outcomes of very low birthweight infants with histologic chorioamnionitis. METHODS: We performed a retrospective analysis of 10,935 single infants born at a gestational age between 22 + 0 and 33 + 6 weeks and birth weight <1,500 g. Clinical data were obtained from the Neonatal Research Network that included the tertiary neonatal intensive care units throughout Japan between 2003 and 2008. RESULTS: Data of 7,896 infants were available for the period 2003-2008 and were included in the analysis. According to logistic regression analysis, AC were significantly associated with reduced mortality [odds ratio (OR) = 0.50; p < 0.001], lower incidence of respiratory distress syndrome (OR = 0.72; p < 0.001), neonatal seizure (OR = 0.65; p = 0.003) and intraventricular hemorrhage (OR = 0.68; p = 0.001) in cases after histologic chorioamnionitis compared with the cases had no AC therapy (n = 3,271 vs. 4,625). Antenatal corticosteroids were significantly associated with reduced mortality [odds ratio (OR) = 0.60; p < 0.001] among the cases without histologic chorioamnionitis. CONCLUSION: In the retrospective population-based study in Japan, AC exposure was significantly associated with a lower rate of death and neurological morbidity in cases with histologic chorioamnionitis. These outcome data in Japan will be important for further improvement of antenatal practice and care.

Impact of comprehensive quality improvement program on outcomes in very-low-birth-weight infants: A cluster-randomized controlled trial in Japan.

BACKGROUND: Differences in outcomes among neonatal intensive care units (NICUs) in Japan have been noted, prompting the need for quality improvement. AIM: To assess a comprehensive quality improvement program on outcomes in very-low-birth-weight (VLBW) infants. STUDY DESIGN: A cluster-randomized clinical trial. SUBJECTS: Forty hospitals and VLBW infants born in 2012-2014 and admitted to those hospitals were study subjects. OUTCOME MEASURES: The intervention group (IG) received a comprehensive quality improvement program involving clinical practice guidelines, educational outreach visits, workshops, opinion leader training, audits, and feedback. The control group (CG) was provided only with the guidelines. The primary outcome was survival without neurological impairment at three years of age. RESULTS: IG consisted of 19 hospitals and 1735 infants, while CG included 21 hospitals and 1700 infants. There were no significant differences in gestational weeks, 29.1(26.9-31.3) vs. 29.1(26.7-31.1) or birth weights (g), 1054(789-1298) vs. 1084(810-1309) between the two groups. Both groups showed survival rates without neurological impairment of 67.2 % (1166) and 66.9 % (1137), respectively, without a significant difference. There was no significant difference in mortalities at NICU discharge between the groups, with rates of 4.0 % (70) and 4.2 % (72) respectively. Several clinically relevant improvements were observed in IG, including reduced rates of sepsis, adrenal insufficiency, transfusion for anemia, and a shorter interval to achieve full enteral feeding. However, these did not lead to improvements in the primary outcome. CONCLUSION: The comprehensive quality improvement program to Japanese NICUs did not result in a significant improvement in survival without neurological impairment in VLBW infants.

Risk factors associated with outcomes of very low birthweight infants in four Asian countries.

AIM: The study aims to determine the risk factors associated with mortality and necrotising enterocolitis (NEC) among very low birthweight infants in 95 neonatal intensive care units in the Asian Network on Maternal and Newborn Health. METHODS: This is a cross-sectional study using an international collaborative database of 17,595 very low birthweight infants admitted within 28 days of birth between 2003 and 2006 in four Asian countries. Information on the mortality and morbidity of neonates admitted to the neonatal intensive care units was recorded. Factors associated with the death and diseases of infants were estimated using multilevel multivariate logistic regression. Random effects were included to account for the clustering of the observations. RESULTS: Overall discharge mortality was 15% and it was significantly different by countries and units. The mortality rate was found to be significantly higher in neonates with pulmonary haemorrhage (odds ratio 1.83, 95% confidence interval 1.63-2.04) and air leak syndrome (odds ratio 1.51, 95% confidence interval 1.30-1.72). The incidence of NEC was 4.3% and was strongly associated with other morbidities. Multivariate logistic regression showed that patent ductus arteriosus was the most significant risk factor associated with NEC. CONCLUSIONS: Our analysis has highlighted the great potential that multi-country, collaborative datasets have in terms of epidemiologic research when it comes to identifying issues in perinatal health that are common throughout Asia, and in relation to particular issues pertaining to specific countries and neonatal units. Establishing collaborative networks, conducting analyses of common datasets and further epidemiologic research are now essential measures to improve newborn health in Asia.

Trends in morbidity and mortality among very-low-birth-weight infants from 2003 to 2008 in Japan.

BACKGROUND: Although medical care for very-low-birth-weight (VLBW) infants has improved over time, it is unclear how this has affected mortality and morbidity. To characterize these trends, a network database was analyzed. METHODS: This is a cohort study of VLBW infants born from 2003 through 2008. RESULTS: Over the 6-y period, 19,344 infants were registered and analyzed. Crude mortality rates among the infants at discharge decreased significantly (from 10.8 to 8.7%) during the study period. The greatest improvement in mortality was observed among infants with birth weights between 501 and 750 g (25.6-17.7 %). The odds ratio (OR) of mortality over year adjusted for potential confounders by a logistic regression model was 0.94 (95% confidence interval 0.92-0.97). Significant increases were observed in some morbidities, including symptomatic patent ductus arteriosus with an OR of 1.11 (1.09-1.13); late-onset adrenal insufficiency, 1.21 (1.17-1.26); and necrotizing enterocolitis/intestinal perforation, 1.10 (1.01-1.12). However, the severe form of intraventricular hemorrhage, with an OR of 0.98 (0.92-0.99), decreased significantly. Risk-adjusted trends in other morbidities showed no significant change. CONCLUSION: Mortality of VLBW infants decreased significantly over the 6-y study period. Decreasing morbidity is essential for further improvement in the outcomes in VLBW infants.

Frequent use of fresh frozen plasma is a risk factor for venous thrombosis in extremely low birth weight infants: a matched case-control study.

Percutaneously inserted central catheters (PICCs) are often used in neonatal medicine. Venous thrombosis (VT) is one of the complications associated with PICC use. According to some reports, fresh frozen plasma (FFP) may be a risk factor for VT. The purpose of this study was to determine whether FFP use is associated with VT in extremely low birth weight infants (ELBWIs). We performed a matched case-control study on risk factors for VT in ELBWIs born over a period of 5 years in the neonatal intensive care unit of a tertiary hospital. Controls were infants from the unit matched for gestational age and birth weight. We performed univariate analyses and created receiver operating characteristic (ROC) curves for the cut-off values of continuous parameters such as FFP. We also conducted multivariate conditional logistic regression analysis and calculated adjusted odds ratios and their 95% confidence intervals. Thirteen VT cases and 34 matched controls were examined. Using an ROC curve, FFP by day 5 > 50 mL/kg was selected as the cut-off value. In multivariate conditional logistic regression analysis, FFP by day 5 > 50 mL/kg exhibited an adjusted odds ratio of 5.88 (95% confidence interval: 1.12-41.81, p = 0.036). FFP by day 5 > 50 mL/kg may be a risk factor for VT in ELBWIs.

Intrauterine Ureaplasma is associated with small airway obstruction in extremely preterm infants.

BACKGROUND: The long-term follow-up of lung function (LF) in extremely preterm (EP) infants with bronchopulmonary dysplasia (BPD) has shown a worldwide increase in small airway obstructions (SAO). OBJECTIVES: We investigated the relationships between intrauterine Ureplasma infection in EP infants and bubbly/cystic lung, BPD, and SAO at school age. METHODS: Placental pathology, placental Ureaplasma DNA (pU-DNA), and cord blood immunoglobulin M (IgM) (C-IgM) were investigated in 360 EP infants born from 1981 to 2004. Maternal amniotic inflammatory response (M-AIR) scores and hemosiderin deposition (HD) were estimated in the chorioamnion. The study subjects were divided into groups based on their M-AIR scores. Their LF at school age was compared with those of 33 healthy siblings. FINDINGS: pU-DNA and C-IgM were significantly related to SAO at school age (p < 0.012). M-AIR score 3 and pU-DNA >1000 units had an odds ratio (OR) of 35 (95% confidence interval: 10-172) and 18 (5.6-67) for bubbly/cystic lung, and 11 (3.1 - 43) and 31 (4.5-349) for severe BPD, and 5.3 (2.1-11) and 12 (2.4-74) for SAO, respectively. The ORs of surfactant treatment, BPD grade III, O2 at 40 weeks, HD, and C-IgM >30 mg/dl for SAO were 0.21 (0.075-0.58), 5.3 (2.1-15), 2.5 (1.4-4.6), 3.6 (1.5-9.1) and 2.5 (1.0-5.2). 84% (90/107) SAO infants showed no or mild BPD in infancy, and 61% of infants had no severe CAM. CONCLUSION: Our long-term cohort study of LF in EP infants revealed that intrauterine Ureaplasma was associated with bubbly/cystic lung, severe BPD, and SAO at school age.

Antenatal corticosteroids promote survival of extremely preterm infants born at 22 to 23 weeks of gestation.

OBJECTIVE: To evaluate the effectiveness of antenatal corticosteroid (ACS) to improve neonatal outcomes for infants born at <24 weeks of gestation. STUDY DESIGN: We performed a retrospective analysis of 11,607 infants born at 22 to 33 weeks of gestation between 2003 and 2007 from the Neonatal Research Network of Japan. We evaluated the gestational age effects of ACS administered to mothers with threatened preterm birth on several factors related to neonatal morbidity and mortality. RESULTS: By logistic regression analysis, ACS exposure decreased respiratory distress syndrome and severe intraventricular hemorrhage in infants born between 24 and 29 weeks of gestation. Cox regression analysis revealed that ACS exposure was associated with a significant decrease in mortality of preterm infants born at 22 or 23 weeks of gestation (adjusted hazard ratio, 0.72; 95% CI, 0.53 to 0.97; P=.03). This effect was also observed at 24 to 25 and 26 to 27 weeks of gestation and in the overall study population. CONCLUSIONS: ACS exposure improved survival of extremely preterm infants. ACS treatment should be considered for threatened preterm birth at 22 to 23 weeks of gestation.

Distribution of birth weight for gestational age in Japanese infants delivered by cesarean section.

BACKGROUND: Neonatal anthropometric charts of the distribution of measurements, mainly birth weight, taken at different gestational ages are widely used by obstetricians and pediatricians. However, the relationship between delivery mode and neonatal anthropometric data has not been investigated in Japan or other countries. METHODS: The subjects were selected from the registration database of the Japan Society of Obstetrics and Gynecology (2003-2005). Tenth centile, median, and 90th centile of birth weight by sex, birth order, and delivery mode were observed by gestational age from 22 to 42 weeks among eligible singleton births. RESULTS: After excluding 248 outliers and 5243 births that did not satisfy the inclusion criteria, 144,980 births were included in the analysis. The distribution of 10th centile curves was skewed toward lower birth weights during the preterm period among both first live births and second and later live births delivered by cesarean section. More than 40% of both male and female live births were delivered by cesarean section at 37 weeks or earlier. CONCLUSIONS: The large proportion of cesarean sections influenced the skewness of the birth weight distribution in the preterm period.

Outcomes of very-low-birthweight infants at 3 years of age born in 2003-2004 in Japan.

BACKGROUND: The aim of this study was to describe and compare neurodevelopmental outcomes with birthweight (BW) groups at 250-g intervals of very-low-birthweight (VLBW) infants at 3 years of age in a multicenter cohort in Japan. METHODS: A total of 3104 VLBW infants born in 2003 and 2004 registered in a NICU-network database were followed in the study. Neurodevelopmental impairment (NDI) was defined as any of the following impairments: cerebral palsy, unilateral or bilateral blindness, severe hearing impairment, or developmental delay; a developmental quotient (DQ) <70 measured using the Kyoto Scale of Psychological Development test or judged by physicians in infants without the test. RESULTS: A total of 257 infants died and follow-up data were obtained from 1826 infants. Of the 1826 infants, 155 (8.5%) had cerebral palsy, 25 (1.4%) had visual impairment, and 12 (0.7%) had hearing impairment. Of the 1197 infants in whom DQ was measured, 184 (15.4%) had DQ < 70. The proportion of NDI in the evaluated infants was 19.2% (n= 350), ranging from 11.9% (BW 1251-1500 g) to 42.0% (BW ≤ 500 g). Odds ratios (95%CI) of NDI or death against the group BW 1251-1500 g were 20.62 (13.29-31.97) in BW ≤ 500 g, 7.25 (5.45-9.64) in BW 501-750 g, 2.85 (2.12-3.82) in BW 751-1000 g and 1.18 (0.85-1.64) in BW 1001-1250 g. CONCLUSION: The increasing proportion of NDI or death, an indicator of adverse outcome, was associated with decrement in the BW of the groups. Although we have to consider a bias due to loss of follow-up data, the incidence of NDI was similar to previous overseas cohort studies despite the higher survival proportion in our study.

Neonatal correlates of adverse outcomes in very low-birthweight infants in the NICU Network.

BACKGROUND: The aim of the present study was to explore the relationships among neonatal morbidity, interventions and death or adverse neurodevelopmental outcomes in very low-birthweight (VLBW) infants. METHODS: Subjects were infants with birthweight ≤ 1500 g who were cared for in the tertiary neonatal intensive care units in Japan. Multiple logistic regression analysis was performed to examine the odds ratios (OR) and 95% confidence intervals (CI) of neonatal factors for death or cerebral palsy (CP) and death or developmental delay (developmental quotient <70 or delay judged by physicians) at 3 years of age after adjusting for biological and prenatal variables. RESULTS: Of the 3104 subjects, 257 died and 1826 were evaluated at 3 years of age. Cystic periventricular leukomalacia (PVL; OR, 23.9; 95%CI: 11.0-51.7), gastrointestinal perforation (OR, 8.5; 95%CI: 2.8-25.4), intraventricular hemorrhage (IVH) grade 3 or 4 (OR, 3.1; 95%CI: 1.3-7.2) and sepsis (OR, 2.6; 95%CI: 1.4-4.8) were neonatal factors significantly associated with an increased risk of death or CP. Significant correlates with death or developmental delay were cystic PVL (OR, 7.9; 95%CI: 3.7-16.8), gastrointestinal perforation (OR, 6.3; 95%CI: 1.9-20.8), sepsis (OR, 2.8; 95%CI: 1.6-4.8), IVH grade 3 or 4 (OR, 2.6; 95%CI: 1.2-5.7), chronic lung disease at 36 weeks of corrected gestational age (OR, 1.6; 95%CI: 1.1-2.4) and treatment for retinopathy of prematurity (ROP; OR, 1.5; 95%CI: 1.0-2.3). CONCLUSION: Cystic PVL, gastrointestinal perforation, IVH and sepsis correlated with both death or CP and death or developmental delay in VLBW infants. Chronic lung disease at 36 weeks and treatment for ROP were associated with death or developmental delay, but not with death or CP.