P25 The national congenital anomaly and rare disease registration service (NCARDRS): data profile, its application and development towards administrative data linkage in England

Background

Child and infant mortality data from the Office for National Statistics for 2020 show that congenital anomalies (CA) were the second most common cause of death in the post-neonatal period, after prematurity, accounting for 36.3% of deaths. CA, particularly congenital heart, genetic and digestive system anomalies, are a common factor in infant and perinatal deaths.

Methods

The National Congenital Anomaly and Rare Disease Registration Service (NCARDRS) is a comprehensive registration service that collects and quality assures data on CA in England. Although congenital anomaly registration has been in place regionally for many years, national data collection started in England in 2018. Three annual reports have been produced describing CA detected in babies delivered between 1 January 2018 and 31 December 2020 in England. Personal identifiers for mothers and babies, including NHS number and postcode of residence, along with key risks factors and demographics including ethnicity and deprivation, are collected and will be linked to other routinely collected datasets such as Hospital Episode Statistics. Linkage to NHS Maternity Services Dataset and the Community Prescriptions Dataset is currently ongoing. NCARDRS data are made available, for those with the requisite permissions, through NHS England.

Results

From the latest data for 2020, 13,065 babies with one or more CA were recorded out of 589,454 total births in England, equal to one baby diagnosed with at least one CA for every 45 total births. The rate of perinatal mortality associated with CA was highest for genetic disorders (3.1 per 10,000 total births, 95% CI 2.7–3.6), followed by congenital heart anomalies (2.8 per 10,000 total births, 95% CI 2.4–3.2). Infant mortality rate was highest for congenital heart anomalies (4.9 per 10,000 live births, 95% CI 4.4–5.5), followed by genetic conditions (3.0 per 10,000 live births, 95% CI 2.6–3.5). The rate of genetic conditions in babies born to mothers over 40 years old was almost 7 times higher relative to babies born to mothers under 20 years old (risk ratio equal to 6.9, 95% CI 5.2–9.2).

Conclusion

Understanding the distribution and causes of child perinatal health conditions such as CA is necessary to tackle early-life mortality and later-life complications, as well as to plan and evaluate supporting measures for children and their families. Supplementing information on existing records via linkage with other routinely collected data sources will improve the ascertainment of postnatally diagnosed conditions, enrich the information held about the mother and baby and the observation of life course development.