Racial Segregation and Intraventricular Hemorrhage in Preterm Infants

Abstract

Background: Intraventricular hemorrhage (IVH) disproportionately affects black neonates. Other conditions that are more common in black neonates, including low birth weight and preterm delivery, have been linked with residential racial segregation (RRS). In this study, we investigated the association between RRS and IVH.

Methods: A retrospective cohort of neonates born between 24 and 32 weeks' gestation was constructed by using birth certificates linked to medical records from California, Missouri, and Pennsylvania between 1995 and 2009. Dissimilarity, a measure of RRS indicating the proportion of minorities in the census tract of the mother in comparison to the larger metropolitan area, was linked to patient data, yielding a cohort of 70 775 infants. Propensity score analysis matched infants born to mothers living in high segregation to those living in less segregated areas on the basis of race, sociodemographic factors, and medical comorbidities to compare the risk of developing IVH.

Results: Infants born to mothers in the most segregated quartile had a greater risk of developing IVH compared with those in the lowest quartile (12.9% vs 10.4%; P < .001). In 17 918 pairs matched on propensity scores, the risk of developing IVH was greater in the group exposed to a segregated environment (risk ratio = 1.08, 95% confidence interval: 1.01-1.15). This effect was stronger for black infants alone (risk ratio = 1.16; 95% confidence interval: 1.03-1.30).

Conclusions: RRS is associated with an increased risk of IVH in preterm neonates, but the effect size varies by race. This association persists after balancing for community factors and birth weight, representing a novel risk factor for IVH.

Figure 1:

Rates of IVH in black and white infants by dissimilarity quartile. Dissimilarity (D), which is a measure of segregation, increases from left to right by quartile. Black infants, represented by the grey bar, showed rising incidence of IVH with higher dissimilarity scores, whereas white infants showed a smaller increase in IVH incidence as dissimilarity increased.