Mortality amongst European children with congenital anomalies: Associations with socio-economic status in the EUROLINKCAT cohort

Background: Childhood mortality is affected by major congenital anomalies and socio-economic status (SES). To our knowledge, their combined impact has not been explored to age 10. Methods: We analysed the population-based EUROlinkCAT cohort to ascertain the impact of SES on mortality by ages 1 and 10 amongst children with congenital anomalies in ten congenital anomaly registers in seven European countries. Four countries defined SES according to maternal education, and two used their national index of multiple deprivation. The ten registers used a common script to generate data on survival by ages 1 and 1-10 (365-3651 days). Eight registers analysed deaths according to their SES criteria, categorised as low, intermediate and high SES. Linked data were combined in random effects meta-analyses. Finland and Emilia-Romagna held data on single motherhood and EU-nationality. Results: We analysed mortality in relation to SES using data on 47,134 live-born children with major congenital anomalies classified and recorded 1996-2014. Mortality by age 1 and ages 1-10 was higher amongst the most than the least deprived, hazard ratios (HR) and 95% confidence intervals (CI) 1.47, 1.19-1.83 and 2.00, 1.32-3.02. Differences between intermediate and least deprived groups were smaller. Differences were statistically significant for all four analyses only in Ukraine and Wales. Mortality rates were higher for children of non-EU nationals, but not single mothers. Implications: Deprivation was more strongly associated with death at ages 1-10 than in infancy. These analyses of the most ill children in Europe indicate that, to achieve sustainable development goals, more resources are needed for the most vulnerable children.