Research Scientist of Epidemiology Carelon Research QUINCY, United States
Background: For pregnancy safety and population-based studies, linking maternal and infant records in administrative health claims is an indispensable tool for studying pregnancy and infant outcomes. Congenital heart defects (CHD) are the most common birth defects with different levels of severity and treatment options. In the US, 1 in 4 infants is born with critical CHD. Detection and diagnoses of CHD are initiated during pregnancy by fetal echocardiogram, although some are not detected until birth or during the first year of life. Normally, infants are enrolled in a health plan within a few days of birth; 1 in 4 infants is not enrolled in their mother’s health plan. Not all infant outcomes can be assessed on maternal records, as not all are evident at birth
Objectives: Examine the characteristics and timing of CHD diagnosis among linked infants in the Healthcare Integrated Research Database (HIRD)
Methods: This is a secondary analysis of a large existing cohort of women with live births and their infants, ages 15-49 years, between 2016-2022. Deterministic matching on subscriber ID was applied to link mothers with delivery claims to their infants. A mother was classified as linked to an infant if the infant’s date of birth was within three days of the delivery date
Results: 42 865 women with live birth claims were identified between 2016 and 2022. Of these, 27 235 (63.5%) had linked infants, and 15 630 (36.5%) had no linked infants. Among all linked infants, 81.1% had a 6-month continuous enrollment, while 62.3% had a 12-month continuous health plan enrollment with a mean enrollment and 95% CI of 1.74 (1.7-1.7) years. Among all infants, 1022 (3.7%) had at least one CHD diagnosed within 7 days compared to 1537 (5.5%) with CHD diagnosed within 365 days of birth. The most common CHD were atrial septal defect (ASD) (3.4%) and ventricular septal defect (VSD) (0.8%). For all ASD and VSD, 65.7% and 68.0% were diagnosed within 7 days of birth. All infants with single ventricle or total anomalous pulmonary venous (TAPVC) were diagnosed within 7 days of birth, as compared to half of the infants with pulmonary atresia or double outlet right ventricle (DORV)
Conclusions: For pregnancy safety studies, it is essential to link mothers and infants. While most infants could be linked to their mother’s health plans, a quarter of infants are not linked. Thus, there is a need to evaluate some outcomes using infants’ health claims. Importantly, not all CHDs detected during pregnancy could be confirmed if the infant had a different health plan. The timing of any CHD diagnosis is essential and depends on the infant’s enrollment in a health plan; by linking mothers’ and infants’ health claims in an extensive integrated research database, we were able to show that approximately two-thirds of CHDs were diagnosed within seven days of birth
