Estimating Global Burden of Disease due to congenital anomaly: an analysis of European data

Abstract

Objective: To validate the estimates of Global Burden of Disease (GBD) due to congenital anomaly for Europe by comparing infant mortality data collected by EUROCAT registries with the WHO Mortality Database, and by assessing the significance of stillbirths and terminations of pregnancy for fetal anomaly (TOPFA) in the interpretation of infant mortality statistics.

Design, setting and outcome measures: EUROCAT is a network of congenital anomaly registries collecting data on live births, fetal deaths from 20 weeks' gestation and TOPFA. Data from 29 registries in 19 countries were analysed for 2005-2009, and infant mortality (deaths of live births at age <1 year) compared with the WHO Mortality Database. Eight EUROCAT countries were excluded from further analysis on the basis that this comparison showed poor ascertainment of survival status.

Results: According to WHO, 17%-42% of infant mortality was attributed to congenital anomaly. In 11 EUROCAT countries, average infant mortality with congenital anomaly was 1.1 per 1000 births, with higher rates where TOPFA is illegal (Malta 3.0, Ireland 2.1). The rate of stillbirths with congenital anomaly was 0.6 per 1000. The average TOPFA prevalence was 4.6 per 1000, nearly three times more prevalent than stillbirths and infant deaths combined. TOPFA also impacted on the prevalence of postneonatal survivors with non-lethal congenital anomaly.

Conclusions: By excluding TOPFA and stillbirths from GBD years of life lost (YLL) estimates, GBD underestimates the burden of disease due to congenital anomaly, and thus declining YLL over time may obscure lack of progress in primary, secondary and tertiary prevention.

Keywords: Congenital anomaly; DALY; Global Burden of Disease; YLL; mortality.

Figure 1

Prevalence per 1000 live births of infant deaths due to congenital anomaly (WHO) and infant deaths with congenital anomaly (EUROCAT) for 29 EUROCAT registries in 19 countries, 2005–2009. *Registries and years as stated in Table 1.

Figure 2

Prevalence per 1000 births of infant deaths with congenital anomaly, by age at death and country, for 19 EUROCAT registries in 11 countries, 2005–2009. *TOPFA, terminations of pregnancy for fetal anomaly. *Years as stated in Table 1. Eleven countries (19 EUROCAT Registries) which ascertain more than 80% of the infant mortality attributed to congenital anomaly recorded by WHO: Austria = Styria; Belgium = Antwerp and Hainaut; Denmark = Odense; Finland; Ireland =Dublin, SE Ireland and Cork & Kerry; Malta; Northern Netherlands; Spain = Basque Country, Sweden; UK= Wales, SW England, Wessex, Northern England, EMSYCAR and Thames Valley; Ukraine.

Figure 3

Proportion of infant deaths among live births with congenital anomaly, by age at death, and association with multiple malformations or syndromes, for 17 EUROCAT registries in nine countries, 2005–2009. *Years as stated in Table 1. Nine countries (17 full member EUROCAT registries) which ascertain more than 80% of the infant mortality attributed to congenital anomaly recorded by WHO:  Austria = Styria; Belgium = Antwerp and Hainaut;  Denmark = Odense; Ireland = Dublin, SE Ireland and Cork & Kerry; Spain = Basque Country; UK = Wales, SW England, Wessex, Northern England, EMSYCAR and Thames Valley;  Ukraine.  *Years as stated in Table 1.

Figure 4

Prevalence of congenital anomaly cases per 1000 births, from before 20 weeks’ pregnancy up to 1 year of age, by legality of TOPFA* for lethal anomalies, Down syndrome, spina bifida, and surgically treated anomalies, for 17 EUROCAT registries in nine countries,** 2005–2009.*** *TOPFA is illegal in Malta and Ireland. **Nine countries (15 full EUROCAT registries)  which ascertain more than 80% of the infant mortality attributed to congenital anomaly recorded by WHO:  Austria = Styria; Belgium = Antwerp and Hainaut;  Denmark = Odense; Ireland = Dublin, SE Ireland and Cork & Kerry; Malta; Northern Neterlands; Spain = Basque Country; UK = Wales, SW England, Wessex, Northern England, EMSYCAR and Thames Valley;  Ukraine. ***years as stated in Table 1 ^Lethal anomalies are anencephaly, bilateral renal agenesis and trisomy 13 and 18^^Anomalies typically requiring surgery are: severe congenital heart defects, digestive system anomalies, abdominal wall defects, craniosynostosis and oro-facial clefts. See Public Health Indicators Khoshnood et al (8) all diagnosed cases” including TOPFA, to all cases surviving to 20 weeks (i.e. excluding TOPFA <20 weeks), to birth (livebirth or stillbirth or late fetal death from 20 weeks gestation), to livebirth, to age one week, 28 days and 1 year.