Elsevier

The Journal of Pediatrics

Volume 177, October 2016, Pages 144-152.e6
The Journal of Pediatrics

Original Article
Neonatal Outcomes of Very Low Birth Weight and Very Preterm Neonates: An International Comparison

Portions of the study were presented at the meeting of the Pediatric Academic Societies, Baltimore, MD, April 30-May 3, 2016.
https://doi.org/10.1016/j.jpeds.2016.04.083Get rights and content

Objective

To compare rates of a composite outcome of mortality or major morbidity in very-preterm/very low birth weight infants between 8 members of the International Network for Evaluating Outcomes.

Study design

We included 58 004 infants born weighing <1500 g at 240–316 weeks' gestation from databases in Australia/New Zealand, Canada, Israel, Japan, Spain, Sweden, Switzerland, and the United Kingdom. We compared a composite outcome (mortality or any of grade ≥3 peri-intraventricular hemorrhage, periventricular echodensity/echolucency, bronchopulmonary dysplasia, or treated retinopathy of prematurity) between each country and all others by using standardized ratios and pairwise using logistic regression analyses.

Results

Despite differences in population coverage, included neonates were similar at baseline. Composite outcome rates varied from 26% to 42%. The overall mortality rate before discharge was 10% (range: 5% [Japan]-17% [Spain]). The standardized ratio (99% CIs) estimates for the composite outcome were significantly greater for Spain 1.09 (1.04-1.14) and the United Kingdom 1.16 (1.11-1.21), lower for Australia/New Zealand 0.93 (0.89-0.97), Japan 0.89 (0.86-0.93), Sweden 0.81 (0.73-0.90), and Switzerland 0.77 (0.69-0.87), and nonsignificant for Canada 1.04 (0.99-1.09) and Israel 1.00 (0.93-1.07). The adjusted odds of the composite outcome varied significantly in pairwise comparisons.

Conclusions

We identified marked variations in neonatal outcomes between countries. Further collaboration and exploration is needed to reduce variations in population coverage, data collection, and case definitions. The goal would be to identify care practices and health care organizational factors, which has the potential to improve neonatal outcomes.

Section snippets

Methods

This retrospective cohort study included infants born weighing <1500 g at 240 to 316 weeks' gestation and admitted to the contributing neonatal units of participating countries during 2007-2010 (2008-2010 for the UKNC). We excluded infants born at <24 weeks' gestation because culture, practices, and guidelines22, 23 concerning resuscitation differed at lower gestational ages, which was reflected in widely differing rates of neonates born at <24 weeks' gestation admitted to networks. This was a

Results

Of the registered total 75 578 neonates in these databases, after exclusions, the final study sample comprised 58 004 (77%) of the 75 578 very low birth weight infants (Table II). Infant characteristics are presented in Table III, with significant differences detected between countries for all characteristics except sex. Notably, the rate of multiple births was greatest in Israel (42%) and lowest in Japan (24%), which also had the lowest rate of antenatal steroid use (49%). The rate of cesarean

Discussion

In this large, multicenter, multinational cohort of very preterm and very low birth weight infants born weighing <1500 g at 240 to 316 weeks' gestation, we identified marked variation in the composite outcome, as well as mortality and each morbidity across countries. For example, Japan had the lowest mortality but the greatest rate of treatment for retinopathy of prematurity, whereas Spain had the greatest mortality but a relatively lower rate of bronchopulmonary dysplasia. These variations

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    Funding for iNeo of Neonates has been provided by a Canadian Institutes of Health Research (FRN87518) Chair in Reproductive and Child Health Services and Policy Research (to P.S.). Additional funding is available at www.jpeds.com (Appendix 2). The authors declare no conflicts of interest.

    Current address: Phoenix Children's Hospital, Phoenix, AZ.

    List of additional investigators of iNeo of Neonates is available at www.jpeds.com (Appendix 1).

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