Hospital care in the first 10 years of life of children with congenital anomalies in six European countries: data from the EUROlinkCAT cohort linkage study.

OBJECTIVE: To quantify the hospital care for children born with a major congenital anomaly up to 10 years of age compared with children without a congenital anomaly. DESIGN, SETTING AND PATIENTS: 79 591 children with congenital anomalies and 2 021 772 children without congenital anomalies born 1995-2014 in six European countries in seven regions covered by congenital anomaly registries were linked to inpatient electronic health records up to their 10th birthday. MAIN OUTCOME MEASURES: Number of days in hospital and number of surgeries. RESULTS: During the first year of life among the seven regions, a median of 2.4% (IQR: 2.3, 3.2) of children with a congenital anomaly accounted for 18% (14, 24) of days in hospital and 63% (62, 76) of surgeries. Over the first 10 years of life, the percentages were 17% (15, 20) of days in hospital and 20% (19, 22) of surgeries. Children with congenital anomalies spent 8.8 (7.5, 9.9) times longer in hospital during their first year of life than children without anomalies (18 days compared with 2 days) and 5 (4.1-6.1) times longer aged, 5-9 (0.5 vs 0.1 days). In the first year of life, children with gastrointestinal anomalies spent 40 times longer and those with severe heart anomalies 20 times longer in hospital reducing to over 5 times longer when aged 5-9. CONCLUSIONS: Children with a congenital anomaly consume a significant proportion of hospital care resources. Priority should be given to public health primary prevention measures to reduce the risk of congenital anomalies.

Risk factors for mortality in infancy and childhood in children with major congenital anomalies: A European population-based cohort study.

BACKGROUND: Preterm birth and young maternal age are known risk factors for infant and childhood mortality. There is limited knowledge of the impact of these risk factors in children born with major congenital anomalies (CAs), who have inherently higher risks of death compared with other children. OBJECTIVES: To investigate the risk factors for mortality up to age 10 years in children born with specific major CAs. METHODS: This population-based cohort study involved 150,198 livebirths from 1995 to 2014 in 13 European CA registries linked to mortality data. Cox proportional hazards models estimated the association of gestational age, maternal age and child's sex with death <1 year and 1-9 years for the whole cohort and by CA subgroup. Hazard ratios (HR) from each registry were pooled using multivariate meta-analysis. RESULTS: Preterm birth had a dose-response association with mortality; compared with infants born at 37+ weeks gestation, those born at <28, 28-31 and 32-36 weeks had 14.88 (95% CI 12.57, 17.62), 8.39 (95% CI 7.16, 9.85) and 3.88 (95% CI 3.40, 4.43) times higher risk of death <1 year, respectively. The corresponding risks at 1-9 years were 4.99 (95% CI 2.94, 8.48), 3.09 (95% CI 2.28, 4.18) and 2.04 (95% CI 1.69, 2.46) times higher, respectively. Maternal age <20 years (versus 20-34 years) was a risk factor for death <1 year (HR 1.30, 95% CI 1.09, 1.54) and 1-9 years (HR 1.58, 95% CI 1.19, 2.10). Females had 1.22 (95% CI 1.07, 1.39) times higher risk of death between 1 and 9 years than males. CONCLUSION: Preterm birth was associated with considerably higher infant and childhood mortality in children with CAs, comparable to estimates reported elsewhere for the background population. Additional risk factors included young maternal age and female sex. Information on risk factors could benefit clinical care and guide counselling of parents following CA diagnoses.

Creating a population-based cohort of children born with and without congenital anomalies using birth data matched to hospital discharge databases in 11 European regions: Assessment of linkage success and data quality.

Linking routinely collected healthcare administrative data is a valuable method for conducting research on morbidity outcomes, but linkage quality and accuracy needs to be assessed for bias as the data were not collected for research. The aim of this study was to describe the rates of linking data on children with and without congenital anomalies to regional or national hospital discharge databases and to evaluate the quality of the matched data. Eleven population-based EUROCAT registries participated in a EUROlinkCAT study linking data on children with a congenital anomaly and children without congenital anomalies (reference children) born between 1995 and 2014 to administrative databases including hospital discharge records. Odds ratios (OR), adjusted by region, were estimated to assess the association of maternal and child characteristics on the likelihood of being matched. Data on 102,654 children with congenital anomalies were extracted from 11 EUROCAT registries and 2,199,379 reference children from birth registers in seven regions. Overall, 97% of children with congenital anomalies and 95% of reference children were successfully matched to administrative databases. Information on maternal age, multiple birth status, sex, gestational age and birthweight were >95% complete in the linked datasets for most regions. Compared with children born at term, those born at ≤27 weeks and 28-31 weeks were less likely to be matched (adjusted OR 0.23, 95% CI 0.21-0.25 and adjusted OR 0.75, 95% CI 0.70-0.81 respectively). For children born 32-36 weeks, those with congenital anomalies were less likely to be matched (adjusted OR 0.78, 95% CI 0.71-0.85) while reference children were more likely to be matched (adjusted OR 1.28, 95% CI 1.24-1.32). Children born to teenage mothers and mothers ≥35 years were less likely to be matched compared with mothers aged 20-34 years (adjusted ORs 0.92, 95% CI 0.88-0.96; and 0.87, 95% CI 0.86-0.89 respectively). The accuracy of linkage and the quality of the matched data suggest that these data are suitable for researching morbidity outcomes in most regions/countries. However, children born preterm and those born to mothers aged <20 and ≥35 years are less likely to be matched. While linkage to administrative databases enables identification of a reference group and long-term outcomes to be investigated, efforts are needed to improve linkages to population groups that are less likely to be linked.

Causes of death in children with congenital anomalies up to age 10 in eight European countries.

BACKGROUND: Congenital anomalies (CAs) increase the risk of death during infancy and childhood. This study aimed to evaluate the accuracy of using death certificates to estimate the burden of CAs on mortality for children under 10 years old. METHODS: Children born alive with a major CA between 1 January 1995 and 31 December 2014, from 13 population-based European CA registries were linked to mortality records up to their 10th birthday or 31 December 2015, whichever was earlier. RESULTS: In total 4199 neonatal, 2100 postneonatal and 1087 deaths in children aged 1-9 years were reported. The underlying cause of death was a CA in 71% (95% CI 64% to 78%) of neonatal and 68% (95% CI 61% to 74%) of postneonatal infant deaths. For neonatal deaths the proportions varied by registry from 45% to 89% and by anomaly from 53% for Down syndrome to 94% for tetralogy of Fallot. In children aged 1-9, 49% (95% CI 42% to 57%) were attributed to a CA. Comparing mortality in children with anomalies to population mortality predicts that over 90% of all deaths at all ages are attributable to the anomalies. The specific CA was often not reported on the death certificate, even for lethal anomalies such as trisomy 13 (only 80% included the code for trisomy 13). CONCLUSIONS: Data on the underlying cause of death from death certificates alone are not sufficient to evaluate the burden of CAs on infant and childhood mortality across countries and over time. Linked data from CA registries and death certificates are necessary for obtaining accurate estimates.

Accuracy of congenital anomaly coding in live birth children recorded in European health care databases, a EUROlinkCAT study.

Electronic health care databases are increasingly being used to investigate the epidemiology of congenital anomalies (CAs) although there are concerns about their accuracy. The EUROlinkCAT project linked data from eleven EUROCAT registries to electronic hospital databases. The coding of CAs in electronic hospital databases was compared to the (gold standard) codes in the EUROCAT registries. For birth years 2010-2014 all linked live birth CA cases and all children identified in the hospital databases with a CA code were analysed. Registries calculated sensitivity and Positive Predictive Value (PPV) for 17 selected CAs. Pooled estimates for sensitivity and PPV were then calculated for each anomaly using random effects meta-analyses. Most registries linked more than 85% of their cases to hospital data. Gastroschisis, cleft lip with or without cleft palate and Down syndrome were recorded in hospital databases with high accuracy (sensitivity and PPV ≥ 85%). Hypoplastic left heart syndrome, spina bifida, Hirschsprung's disease, omphalocele and cleft palate showed high sensitivity (≥ 85%), but low or heterogeneous PPV, indicating that hospital data was complete but may contain false positives. The remaining anomaly subgroups in our study, showed low or heterogeneous sensitivity and PPV, indicating that the information in the hospital database was incomplete and of variable validity. Electronic health care databases cannot replace CA registries, although they can be used as an additional ascertainment source for CA registries. CA registries are still the most appropriate data source to study the epidemiology of CAs.

Hospital length of stay among children with and without congenital anomalies across 11 European regions-A population-based data linkage study.

BACKGROUND: Congenital anomalies are a leading cause of childhood morbidity, but little is known about the long-term outcomes. OBJECTIVE: To quantify the burden of disease in childhood for children with congenital anomalies by assessing the risk of hospitalisation, the number of days spent in hospital and proportion of children with extended stays (≥10 days). METHODS: European population-based record-linkage study in 11 regions in eight countries including children with congenital anomalies (EUROCAT children) and without congenital anomalies (reference children) living in the same regions. The children were born between 1995 and 2014 and were followed to their tenth birthday or 31/12/2015. European meta-analyses of the outcome measures were performed by two age groups, <1 year and 1-4 years. RESULTS: 99,416 EUROCAT children and 2,021,772 reference children were linked to hospital databases. Among EUROCAT children, 85% (95%-CI: 79-90%) were hospitalised in the first year and 56% (95%-CI: 51-61%) at ages 1-4 years, compared to 31% (95%-CI: 26-37%) and 25% (95%-CI: 19-31%) of the reference children. Median length of stay was 2-3 times longer for EUROCAT children in both age groups. The percentages of children with extended stays (≥10 days) in the first year were 24% (95%-CI: 20-29%) for EUROCAT children and 1% (95%-CI: 1-2%) for reference children. The median length of stay varied greatly between congenital anomaly subgroups, with children with gastrointestinal anomalies and congenital heart defects having the longest stays. CONCLUSIONS: Children with congenital anomalies were more frequently hospitalised and median length of stay was longer. The outlook improves after the first year. Parents of children with congenital anomalies should be informed about the increased hospitalisations required for their child's care and the impact on family life and siblings, and they should be adequately supported.

Temporal and geographical variations in survival of children born with congenital anomalies in Europe: A multi-registry cohort study.

BACKGROUND: Congenital anomalies are a major cause of perinatal, neonatal and infant mortality. OBJECTIVES: The aim was to investigate temporal changes and geographical variation in survival of children with major congenital anomalies (CA) in different European areas. METHODS: In this population-based linkage cohort study, 17 CA registries members of EUROCAT, the European network for the surveillance of CAs, successfully linked data on 115,219 live births with CAs to mortality records. Registries estimated Kaplan-Meier survival at 28 days and 5 years of age and fitted Cox's proportional hazards models comparing mortality at 1 year and 1-9 years of age for children born during 2005-2014 with those born during 1995-2004. The hazard ratios (HR) from each registry were combined centrally using a random-effects model. The 5-year survival conditional on having survived to 28 days of age was calculated. RESULTS: The overall risk of death by 1 year of age for children born with any major CA in 2005-2014 decreased compared to 1995-2004 (HR 0.68, 95% confidence interval [CI] 0.53, 0.89). Survival at 5 years of age ranged between registries from 97.6% to 87.0%. The lowest survival was observed for the registry of OMNI-Net (Ukraine) (87.0%, 95% CI 86.1, 87.9). CONCLUSIONS: Survival of children with CAs improved for births in 2005-2014 compared with 1995-2004. The use of CA registry data linked to mortality data enables investigation of survival of children with CAs. Factors such as defining major CAs, proportion of terminations of pregnancy for foetal anomaly, source of mortality data and linkage methods are important to consider in the design of future studies and in the interpretation of the results on survival of children with CAs.

Signal Detection in EUROmediCAT: Identification and Evaluation of Medication-Congenital Anomaly Associations and Use of VigiBase as a Complementary Source of Reference.

INTRODUCTION: Knowledge on the safety of medication use during pregnancy is often sparse. Pregnant women are generally excluded from clinical trials, and there is a dependence on post-marketing surveillance to identify teratogenic medications. AIMS: This study aimed to identify signals of potentially teratogenic medications using EUROmediCAT registry data on medication exposure in pregnancies with a congenital anomaly, and to investigate the use of VigiBase reports of adverse events of medications in the evaluation of these signals. METHODS: Signals of medication-congenital anomaly associations were identified in EUROmediCAT (21,636 congenital anomaly cases with 32,619 medication exposures), then investigated in a subset of VigiBase (45,749 cases and 165,121 exposures), by reviewing statistical reporting patterns and VigiBase case reports. Evidence from the literature and quantitative and qualitative aspects of both datasets were considered before recommending signals as warranting further independent investigation. RESULTS: EUROmediCAT analysis identified 49 signals of medication-congenital anomaly associations. Incorporating investigation in VigiBase and the literature, these were categorised as follows: four non-specific medications; 11 likely due to maternal disease; 11 well-established teratogens; two reviewed in previous EUROmediCAT studies with limited additional evidence; and 13 with insufficient basis for recommending follow-up. Independent investigations are recommended for eight signals: pregnen (4) derivatives with limb reduction; nitrofuran derivatives with cleft palate and patent ductus arteriosus; salicylic acid and derivatives with atresia or stenosis of other parts of the small intestine and tetralogy of Fallot; carbamazepine with atrioventricular septal defect and severe congenital heart defect; and selective beta-2-adrenoreceptor agonists with posterior urethral valve and/or prune belly. CONCLUSION: EUROmediCAT data should continue to be used for signal detection, accompanied by information from VigiBase and review of the existing literature to prioritise signals for further independent evaluation.