First-year survival of infants born with congenital heart defects in Arkansas (1993-1998): a survival analysis using registry data

Abstract

Background: In the United States and other developed nations, birth defects are the leading cause of infant mortality. Congenital heart defects (CHDs) are among the most prevalent and fatal of all birth defects. Here we report the survival probability of infants born with CHDs in Arkansas and examine the impact of multiple malformations on survival.

Methods: Birth and death certificate records were linked to birth defects registry data for infants born with CHDs from January 1993 through December 1998 in Arkansas. Both neonatal and first-year survival probabilities were estimated. These were computed non-parametrically using Kaplan-Meier's product limit method. A Cox proportional-hazards model was used to evaluate the relative importance of additional malformations on survival.

Results: A total of 1,983 infants with CHDs were included in this study. The neonatal survival probability for this cohort was 94.0% (95% CI: 93.0%, 95.1%), and the first-year survival probability was 88.2% (95% CI: 86.8%, 89.6%). The presence of hypoplastic left heart syndrome conferred the greatest reduction in survival, whereas infants with pulmonic valve stenosis and infants with ventricular septal defects had the highest first-year survival. Infants with multiple CHDs had decreased survival compared to those with isolated heart defects. Survival was also adversely affected by the presence of congenital abnormalities in other body systems.

Conclusions: Neonatal and first-year survival of infants with CHDs varies by both the type of cardiac malformation and the presence of additional cardiac and non-cardiac malformations. Further work will focus on the effects of maternal and infant characteristics on survival.