To determine the importance of infant factors, maternal prenatal care use, and demographic characteristics in explaining the racial disparity in infant (age <365 days) mortality due to congenital heart defects (CHD).Study design
In this cross-sectional population-based study, stratified and multivariable logistic regression analyses were performed on the 2003-2004 National Center for Health Statistics linked live birth–infant death cohort files of term infants with non-Hispanic white (n = 3 684 569) and African-American (n = 782 452) US-born mothers. Infant mortality rate, including its neonatal (<28 day) and postneonatal (28-364 day) components, due to CHD was the outcome measured.Results
The infant mortality rate due to CHD for African-American infants (296 deaths; 3.78 per 10 000 live births) exceeded that of white infants (1025 deaths; 2.78 per 10 000 live births) (relative risk [RR], 1.36; 95% CI, 1.20-1.55). The racial disparity was wider in the postneonatal period (2.08 per 10 000 vs 1.42 per 10 000; RR, 1.53; 95% CI, 1.29-1.83) compared with the neonatal period (1.70 per 10 000 vs 1.44 per 10 000; RR, 1.20; 95% CI, 0.99-1.45). Compared with white mothers, African-American mothers had a higher percentage of high-risk characteristics. In multivariable logistic regression models, the adjusted OR of postneonatal and neonatal mortality due to CHD for African-American mothers compared with white mothers was 1.20 (95% CI, 0.98-1.48) and 0.95 (95% CI, 0.77-1.19), respectively.Conclusion
The racial disparity in infant mortality rate due to CHD among term infants with US-born mothers is driven predominately by the postneonatal survival disadvantage of African-American infants. Commonly cited individual-level risk factors partly explain this phenomenon. The study is limited by the lack of information on neighborhood factors.