Differential Effects of the Single-Family Room Neonatal Intensive Care Unit on 18- to 24-Month Bayley Scores of Preterm Infants

Objectives To determine the effects of human milk and social/environmental disparities on developmental outcomes of infants born preterm cared for in a single-family room (SFR) neonatal intensive care unit (NICU). Study design Outcomes were compared between infants weighing ≤1250 g cared for in an open-bay NICU (1/2007-8/2009) (n = 394) and an SFR NICU (1/2010-12/2011) (n = 297). Human milk provision at 1 week, 4 weeks and discharge, and 4 week volume (mL/kg/day) were analyzed. At 18-24 months of age, the Bayley III was administered. Group differences were evaluated and multiple linear regression analyses were run. Results Infants cared for in the SFR NICU had higher Bayley III cognitive and language scores, higher rates of human milk provision at 1 and 4 weeks, and higher human milk volume at 4 weeks. In adjusted regression models, the SFR NICU was associated with a 2.55-point increase in Bayley cognitive scores and 3.70-point increase in language scores. Every 10 mL/kg/day increase of human milk at 4 weeks was independently associated with increases in Bayley cognitive, language, and motor scores (0.29, 0.34, and 0.24, respectively). Medicaid was associated with decreased cognitive (−4.11) and language (−3.26) scores, and low maternal education and non-white race with decreased language scores (−4.7 and −5.8, respectively). Separate models by insurance status suggest there are differential benefits from SFR NICU and human milk between infants with Medicaid and private insurance. Conclusions Infants born preterm cared for in the SFR NICU have higher Bayley language and cognitive scores and receive more human milk. Independent effects on outcomes were derived from SFR NICU, provision of human milk, and social and environmental factors.