Maternal education and cognitive development in 15 European very-preterm birth cohorts from the RECAP Preterm platform.

BACKGROUND: Studies are sparse and inconclusive about the association between maternal education and cognitive development among children born very preterm (VPT). Although this association is well established in the general population, questions remain about its magnitude among children born VPT whose risks of medical and developmental complications are high. We investigated the association of maternal education with cognitive outcomes in European VPT birth cohorts. METHODS: We used harmonized aggregated data from 15 population-based cohorts of children born at <32 weeks of gestational age (GA) or <1500 g from 1985 to 2013 in 13 countries with information on maternal education and assessments of general development at 2-3 years and/or intelligence quotients between 4 and 15 years. Term-born controls (≥37 weeks of GA) were available in eight cohorts. Maternal education was classified as: low (primary/lower secondary); medium (upper secondary/short tertiary); high (bachelor's/higher). Pooled standardized mean differences (SMDs) in cognitive scores were estimated (reference: high educational level) for children assessed at ages 2-3, 4-7 and 8-15 years. RESULTS: The study included 10 145 VPT children from 12 cohorts at 2-3 years, 8829 from 12 cohorts at 4-7 years and 1865 children from 6 cohorts at 8-15 years. Children whose mothers had low, compared with high, educational attainment scored lower on cognitive measures [pooled unadjusted SMDs: 2-3 years = -0.32 (95% confidence intervals: -0.43 to -0.21); 4-7 years = -0.57 (-0.67; -0.47); 8-15 years = -0.54 (-0.72; -0.37)]. Analyses by GA subgroups (<27 vs ≥27 weeks) in children without severe neonatal morbidity and term controls yielded similar results. CONCLUSIONS: Across diverse settings and regardless of the degree of prematurity, low maternal education was associated with lower cognition.

EPICE cohort: two-year neurodevelopmental outcomes after very preterm birth.

OBJECTIVE: To determine whether the variation in neurodevelopmental disability rates between populations persists after adjustment for demographic, maternal and infant characteristics for an international very preterm (VPT) birth cohort using a standardised approach to neurodevelopmental assessment at 2 years of age. DESIGN: Prospective standardised cohort study. SETTING: 15 regions in 10 European countries. PATIENTS: VPT births: 22+0-31+6 weeks of gestation. DATA COLLECTION: Standardised data collection tools relating to pregnancy, birth and neonatal care and developmental outcomes at 2 years corrected age using a validated parent completed questionnaire. MAIN OUTCOME MEASURES: Crude and standardised prevalence ratios calculated to compare rates of moderate to severe neurodevelopmental impairment between regions grouped by country using fixed effects models. RESULTS: Parent reported rates of moderate or severe neurodevelopmental impairment for the cohort were: 17.3% (ranging 10.2%-26.1% between regions grouped by country) with crude standardised prevalence ratios ranging from 0.60 to 1.53. Adjustment for population, maternal and infant factors resulted in a small reduction in the overall variation (ranging from 0.65 to 1.30). CONCLUSION: There is wide variation in the rates of moderate to severe neurodevelopmental impairment for VPT cohorts across Europe, much of which persists following adjustment for known population, maternal and infant factors. Further work is needed to investigate whether other factors including quality of care and evidence-based practice have an effect on neurodevelopmental outcomes for these children.

Duration and Time Trends in Hospital Stay for Very Preterm Infants Differ Across European Regions.

OBJECTIVES: To compare duration and changes over time in length of hospital stay for very preterm and extremely preterm infants in 10 European regions. DESIGN: Two area-based cohort studies from the same regions in 2003 and 2011/2012. SETTING: Ten regions from nine European countries. PATIENTS: Infants born between 22 + 0 and 31 + 6 weeks of gestational age and surviving to discharge (Models of Organising Access to Intensive Care for Very Preterm Births cohort in 2003, n = 4,011 and Effective Perinatal Intensive Care in Europe cohort in 2011/2012, n = 4,336). INTERVENTIONS: Observational study, no intervention. MEASUREMENTS AND MAIN RESULTS: Maternal and infant characteristics were abstracted from medical records using a common protocol and length of stay until discharge was adjusted for case-mix using negative binomial regression. Mean length of stay was 63.6 days in 2003 and varied from 52.4 to 76.5 days across regions. In 2011/2012, mean length of stay was 63.1 days, with a narrower regional range (54.0-70.1). Low gestational age, small for gestational age, low 5-minute Apgar score, surfactant administration, any surgery, and severe neonatal morbidities increased length of stay. Infant characteristics explained some of the differences between regions and over time, but large variations remained after adjustment. In 2011/2012, mean adjusted length of stay ranged from less than 54 days in the Northern region of the United Kingdom and Wielkopolska, Poland to over 67 days in the Ile-de-France region of France and the Eastern region of the Netherlands. No systematic decrease in very preterm length of stay was observed over time after adjustment for patient case-mix. CONCLUSIONS: A better understanding of the discharge criteria and care practices that contribute to the wide differences in very preterm length of stay across European regions could inform policies to optimize discharge decisions in terms of infant outcomes and health system costs.

Rates of bronchopulmonary dysplasia in very preterm neonates in Europe: results from the MOSAIC cohort.

BACKGROUND: A considerable local variability in the rate of bronchopulmonary dysplasia (BPD) has been recorded previously. OBJECTIVES: The objectives of the present study were to describe regional differences in the rate of BPD in very preterm neonates from a European population-based cohort and to further delineate risk factors. METHODS: 4,185 survivors to 36 weeks' postmenstrual age of 4,984 live-born infants born at 24+0-31+6 weeks' gestation in 2003 (the MOSAIC cohort) in 10 European regions were enrolled using predefined structured questionnaires. RESULTS: Overall median gestational age of preterms without BPD was 30 weeks (range 23-31), median birth weight 1,320 g (range 490-3,150) compared with 27 weeks (23-31) and 900 g (370-2,460) in those with BPD. The region-specific crude rate of BPD ranged from 10.2% (Italian region) to 24.8% (UK Northern region). Maternal hypertension, immaturity, male gender, small for gestational age, Apgar <7 and region of care were associated with an increased incidence of BPD on multivariate analysis. CONCLUSION: A wide variability of BPD between European regions may be explained by different local practices; the strongest association however was with degree of immaturity.

Differences in rates and short-term outcome of live births before 32 weeks of gestation in Europe in 2003: results from the MOSAIC cohort.

OBJECTIVES: Advances in perinatal medicine increased survival after very preterm birth in all countries, but comparative population-based data on these births are not readily available. This analysis contrasts the rates and short-term outcome of live births before 32 weeks of gestation in 10 European regions. METHODS: The Models of Organizing Access to Intensive Care for Very Preterm Births (MOSAIC) study collected prospective data on all very preterm births in 10 European regions covering 494,463 total live births in 2003. The analysis sample was live births between 24 and 31 weeks of gestation without lethal congenital anomalies (N = 4908). Outcomes were rates of preterm birth, in-hospital mortality, intraventricular hemorrhage grades III and IV or cystic periventricular leukomalacia and bronchopulmonary dysplasia. Mortality and morbidity rates were standardized for gestational age and gender. RESULTS: Live births between 24 and 31 weeks of gestation were 9.9 per 1000 total live births with a range from 7.6 to 13.0 in the MOSAIC regions. Standardized mortality was doubled in high versus low mortality regions (18%-20% vs 7%-9%) and differed for infants < or = 28 weeks of gestation as well as 28 to 31 weeks of gestation. Morbidity among survivors also varied (intraventricular hemorrhage/periventricular leukomalacia ranged from 2.6% to < or = 10% and bronchopulmonary dysplasia from 10.5% to 21.5%) but differed from mortality rankings. A total of 85.2 very preterm infants per 10,000 total live births were discharged from the hospital alive with a range from 64.1 to 117.1; the range was 10 to 31 per 10,000 live births for infants discharged with a diagnosis of neurologic or respiratory morbidity. CONCLUSIONS: Very preterm mortality and morbidity differed between European regions, raising questions about variability in treatment provided to these infants. Comparative follow-up studies are necessary to evaluate the impact of these differences on rates of cerebral palsy and other disabilities associated with preterm birth.