河野 由美

BACKGROUND: The Improvement of Neonatal Intensive Care Unit (NICU) Practices and Team Approach Cluster-randomized Controlled Trial (INTACT) tested a multidisciplinary quality improvement (QI) program but did not show improved survival without neurodevelopmental impairment at 3 years among infants with very low birthweight. However, the program's potential effect on acute-phase outcomes in extremely preterm infants (< 28 weeks of gestation) warrants further evaluation. This secondary analysis aimed to assess the effect of the INTACT study's QI intervention based on participatory learning and action on acute morbidities during the NICU stay and outcomes at 3 years of age. METHODS: We performed a secondary analysis of data from the INTACT trial, a cluster-randomized controlled trial conducted in 40 Japanese NICUs from 2012-2014. Infants were stratified into two gestational age groups (22-24 weeks and 25-27 weeks). The primary outcome was a composite of seven acute morbidities (pulmonary air leak syndrome, pulmonary hemorrhage, sepsis, severe intraventricular hemorrhage, intestinal perforation, necrotizing enterocolitis, or circulatory collapse) between the intervention (QI program) and control groups. Secondary outcomes included chronic morbidities diagnosed before NICU discharge and long-term outcomes at 3 years of age. Multivariable logistic regression and Holm's correction for multiple comparisons were applied. RESULTS: In the 25-27-week subgroup, the intervention group showed a significantly lower rate of composite acute morbidity than the control group (31.3% vs. 40.3%; adjusted odds ratio [OR] 0.67; 95% confidence interval 0.50-0.90; p = 0.008). In the 22-24-week subgroup, composite acute morbidity did not differ significantly; however, sepsis (adjusted OR: 0.44, Holm-adjusted p = 0.010) and pulmonary hemorrhage (adjusted OR: 0.27, Holm-adjusted p = 0.028) were significantly reduced. After multivariable adjustment and Holm correction, no differences in neurodevelopmental outcomes at 3 years of age were observed between groups. CONCLUSIONS: This secondary analysis of a cluster-randomized controlled trial demonstrated that the intervention group receiving a NICU-specific QI program had reduced acute-phase morbidities, particularly among infants born between 22 and 27 weeks of gestation. Our findings highlight the potential for widespread clinical implementation of QI programs based on participatory learning and action in neonatal intensive care.

OBJECTIVE: To evaluate neurodevelopmental outcomes of very preterm infants by gestational age (GA) using high follow-up rate data. STUDY DESIGN: This secondary analysis included infants born before 32 weeks' gestation in 2012-2014 from the Improvement of NICU practices and Team Approach Cluster randomized controlled Trial (INTACT). The primary outcome was survival without moderate or severe neurodevelopmental impairment (NDI). RESULTS: Among 2722 infants, NICU survival rate was 96.5%, ranging 72.1-99.6% at 22-31 weeks. At age three years, 2336 (89.5% of 2610 survivors) were completely assessed; 303 had moderate NDI and 183 had severe NDI. Of these, the proportions of infants surviving without NDI increased with GA; 45.2% at 22 weeks, 57.5% at 23 weeks, 88.1% at 31 weeks. CONCLUSION: Although survival without NDI varied by GA, more than half (55.0%, 83/151) of infants born at 22-23 weeks who survived to age three years were without neurodevelopmental sequelae.