Epidemiological Aspects, Prenatal Screening and Diagnosis of Congenital Heart Defects in Beijing

Abstract

Background: In China, congenital heart disease (CHD) is the most common birth defect type, with approximately 13,000 new cases annually. This study aimed to investigate high-risk factors, prenatal screening and prenatal diagnosis as a basis for clinical decisions.Methods: All CHD cases identified from 2018 to 2020 were obtained from the Beijing city birth defect surveillance system and prenatal diagnosis institutions. The prenatal CHD diagnosis was confirmed by fetal echocardiography and amniotic fluid or cord blood genetic examination. Chi-square, odds ratio (OR), 95% confidence interval (CI), and univariate and multivariate logistic analyses were used to explore the high-risk factors, prenatal screening and prenatal diagnosis of CHD. Results: In total, 6,786/594,860 fetuses with CHD were diagnosed by prenatal echocardiography. The average incidence of CHD was 11.4 per 1,000 births, with an increase of 30.7 per 1,000 births from 2018 to 2020 (P < 0.05); the average incidence of complex CHD (CCHD) was 2.02 per 1,000 births, with no significant change from 2018 to 2020 (P > 0.05). Women age ≥35 years (OR 1.06, 95% CI 0.77–1.46) was at higher risk of having babies with CHD than women aged 21–34 years. Overall, CHD incidence increased with maternal age (OR1.03, 95% CI 1.02–1.03). Additionally, women who had a non-local household registration (OR 1.16, 95% CI 1.10–1.22) or had diabetes mellitus (DM) (OR 1.16, 95% CI 0.96–1.25) were at higher risk of CHD. As an independent factor, CCHD was related to maternal age, DM, fetal gender, and maternal education level (all P < 0.05). The prenatal ultrasound screening detection rate of CCHD was 97.59%, which was far higher than that of total CHD (51.67%) (P < 0.001). The prenatal ultrasound diagnosis rate of CCHD was higher than that of simple CHD (P < 0.001), but the coincidence rate in the ultrasound diagnosis of CCHD was lower than that of simple CHD (P < 0.001). Prenatal genetic testing revealed chromosomal abnormalities in 25.62% (279/1089) of CHD cases with indications for a prenatal diagnosis.Conclusions: Maternal age, household registration and DM were related to CHD occurrence. Prenatal ultrasound screening is a highly effective method for CCHD diagnosis, and CHD fetuses should be closely evaluated to exclude chromosomal abnormalities.

Birth defects data from hospital-based birth defect surveillance in Guilin, China, 2018–2020

“…Among the BDs, we found that CHD was the most common type of BD and its prevalence rate increased from 2.61 per 1000 births in 2018 to 4.56 per 1,000 births in 2020, the increase trend was consistent with the results of most previous studies in China and other countries (1,9,21). This phenomenon can be explained to some extent by the increasing proportion of older pregnant women, increasing social or natural environmental pressure, improvement in diagnostic techniques, for example, Bultrasound, and advances in the ascertainment of CHD (1,9). Although CHD was the most common type of BD in Guilin, the prevalence of CHD (total: 3.43 per 1,000 births) was still much lower than the global rate of 8-10 per 1,000 births (9).…”

“…Unfortunately, only 177 cases (8.84%) were assigned a known etiology in Guilin in 2018-2020, and the low proportion of BDs with known etiology may be attributed to several reasons. The first reason may be the low level of economic and technological development in Guilin; for example, although an increasing in the prevalence of genetic abnormalities in CHD patients was reported recently (2,9), only 1 in 507 CHD patients underwent genetic testing in Guilin (data not shown). Second, there was incomplete data collection and specialists in registered hospitals did not record some exposures (such as maternal infection, medication, pregestational diabetes) or query relevant information.…”

“…This phenomenon can be explained to some extent by the increasing proportion of older pregnant women, increasing social or natural environmental pressure, improvement in diagnostic techniques, for example, B-ultrasound, and advances in the ascertainment of CHD ( 1 , 9 ). Although CHD was the most common type of BD in Guilin, the prevalence of CHD (total: 3.43 per 1,000 births) was still much lower than the global rate of 8–10 per 1,000 births ( 9 ). The low prevalence of CHD in Guilin may be due to several reasons.…”

“…Herein, CHD cases were mostly detected in the “Postpartum diagnosis within 7 days” (89.15%) ( Supplementary Table 2 ). In the USA, the follow-up time for CHD cases is up to at least 1 year or without age limitation ( 4 , 9 ). Third, some low-income pregnant women delivered in the hospital without any prenatal or postpartum diagnosis of CHD, resulting in missing or incomplete information.…”

“…Furthermore, commonly used BD classification schemes were International Statistical Classification of Diseases and Related Health Problems (ICD), such as 9th or 10th revision (ICD-9, or ICD-10) ( 2 , 9 , 10 ). ICD is the standard used globally to classify diseases including birth defects.…”