Janevic T, et al. - Among very preterm infants, researchers estimated racial/ethnic differences in severe morbidities. The results obtained from this population-based retrospective cohort study indicate that racial/ethnic disparities in very preterm neonatal morbidity are sizeable, and reports from very preterm birth cohorts might underestimate the magnitude of these disparities. They emphasized that understanding these racial/ethnic disparities is important, as they might contribute to inequalities in health and development later in the child’s life.

Methods

• Using linked birth certificate, mortality data, and hospital discharge data from January 1, 2010, through December 31, 2014, researchers performed this investigation in New York City, New York.
• They excluded infants born before 24 weeks’ gestation, with congenital anomalies, and with missing data.
• They assessed racial/ethnic disparities in very preterm birth morbidities through 2 approaches (conventional analysis and fetuses-at-risk analysis).
• In the conventional analysis, they used log-binomial regression to estimate the relative risk of 4 severe neonatal morbidities for the racial/ethnic groups.
• Cox proportional hazards regression with death as competing risk was used to estimate subhazard ratios associating race/ethnicity with each outcome for the fetuses-at-risk analysis.
• They adjusted estimates for sociodemographic factors and maternal morbidities.
• From September 5, 2017, to May 21, 2018, data were analyzed.
• Four morbidity outcomes were characterized utilizing International Classification of Diseases, Ninth Revision, diagnosis and procedure codes: necrotizing enterocolitis, intraventricular hemorrhage, bronchopulmonary dysplasia, and retinopathy of prematurity.

Results

• Study participants were 582,297 infants (285,006 were female (48.9%) and 297,291 were male [51.0%]).
• Black vs white infants had an increased risk of only bronchopulmonary dysplasia (adjusted risk ratio [aRR], 1.34; 95% CI, 1.09-1.64) and a borderline increased risk of necrotizing enterocolitis (aRR, 1.39; 95% CI, 1.00-1.93) using the conventional approach in the very preterm birth subcohort.
• Borderline increased risk of necrotizing enterocolitis (aRR, 1.39; 95% CI, 0.98-1.96) was observed in Hispanic infants, and increased risk of retinopathy of prematurity (aRR, 1.85; 95% CI, 1.15-2.97) was noted in Asian infants.
• Black infants had a 4.40 times higher rate of necrotizing enterocolitis (95% CI, 2.98-6.51), a 2.73 times higher rate of intraventricular hemorrhage (95% CI, 1.63-4.57), a 4.43 times higher rate of bronchopulmonary dysplasia (95% CI, 2.88-6.81), and a 2.98 times higher rate of retinopathy of prematurity (95% CI, 2.01-4.40) in the fetuses-at-risk analysis.
• Approximately 2 times higher rate for all outcomes was found in Hispanic infants, and increased risk only for retinopathy of prematurity (adjusted hazard ratio, 2.43; 95% CI, 1.43-4.11) was discovered in Asian infants.