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The impact of volume and neonatal level of care on outcomes of moderate and late preterm infants

Journal of Perinatology (2024)Cite this article

Subjects

Abstract

Objective

Evaluate the relationship of neonatal unit level of care (LOC) and volume with mortality or morbidity in moderate-late preterm (MLP) (32–36 weeks’ gestation) infants.

Design

Retrospective cohort study of 650,865 inborn MLP infants in 4976 hospitals-years using 2003–2015 linked administrative data from 4 states. Exposure was combined neonatal LOC and MLP annual volume. The primary outcome was death or morbidity (respiratory distress syndrome, severe intraventricular hemorrhage, necrotizing enterocolitis, sepsis, infection, pneumothorax, extreme length of stay) with components as secondary outcomes. Poisson regression models adjusted for patient characteristics with a random effect for unit were used.

Results

In adjusted models, high-volume level 2 units had a lower risk of the primary outcome compared to low-volume level 3 units (aIRR 0.90 [95% CI 0.83–0.98] vs. aIRR 1.13 [95% CI 1.03–1.24], p < 0.001)

Conclusion

MLP infants had improved outcomes in high-volume level 2 units compared to low-volume level 3 units in adjusted analysis.

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Fig. 1: Association between level-volume and composite outcome in moderate and late preterm infants.
Fig. 2: Association between level-volume and composite outcome in moderate and late preterm groups.

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Data availability

Deidentified individual participant data cannot be made available by the authors due to restrictions in the data use agreements by which the data were obtained. Access to these data and associated code must be requested via a data use agreement with the respective states.

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Acknowledgements

PA: The Pennsylvania Health Care Cost Containment Council (PHC4) is an independent state agency responsible for addressing the problem of escalating health costs, ensuring the quality of health care, and increasing access to health care for all citizens regardless of ability to pay. PHC4 has provided data to this entity in an effort to further PHC4’s mission of educating the public and containing health care costs in Pennsylvania. PHC4, its agents, and staff, have made no representation, guarantee, or warranty, express or implied, that the data -- financial, patient, payor, and physician specific information -- provided to this entity, are errorfree, or that the use of the data will avoid differences of opinion or interpretation. This analysis was not prepared by PHC4. This analysis was done by the aforementioned authors. PHC4, its agents and staff, bear no responsibility or liability for the results of the analysis, which are solely the opinion of this entity. MO: The data used in this document/presentation was acquired from the Missouri Department of Health and Senior Services (DHSS). The contents of this document including data analysis, interpretation or conclusions are solely the responsibility of the authors and do not represent the official views of DHSS. SC: This information is from the records of the Revenue and Fiscal Affairs Office, Health and Demographics Section, South Carolina. Our authorization to release this information does not imply endorsement of this study or its findings by either the revenue and fiscal affairs office or the data oversight council.

Funding

T32HL098054 (to EGS). R01HD084819 (to CSP, SAL). K23HD109426 (to SCH).

Author information

Authors and Affiliations

  1. Division of Neonatology, Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA

    Elizabeth G. Salazar, Molly Passarella, Brielle Formanowski, Scott A. Lorch & Sara C. Handley

  2. Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA, USA

    Elizabeth G. Salazar, Scott A. Lorch & Sara C. Handley

  3. Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA

    Elizabeth G. Salazar, Scott A. Lorch & Sara C. Handley

  4. Stanford University School of Medicine, Stanford, CA, USA

    Ciaran S. Phibbs

  5. Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA

    Ciaran S. Phibbs

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  1. Elizabeth G. Salazar
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Contributions

Dr. Elizabeth Salazar designed the study, drafted the initial manuscript, reviewed, and revised the manuscript. Dr. Sara Handley conceptualized and designed the study, critically reviewed, and revised the manuscript. Brielle Formanowski and Molly Passarella carried out the analyses, critically reviewed and revised the manuscript. Dr. Scott Lorch conceptualized and designed the study, obtained grant funding for the creation of the data source for the project, as well as critically reviewed and revised the manuscript. Dr. Ciaran Phibbs provided critical feedback on study methodology, obtained grant funding for the creation of the data source for the project, as well as reviewed and revised the manuscript. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

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Correspondence to Elizabeth G. Salazar.

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Salazar, E.G., Passarella, M., Formanowski, B. et al. The impact of volume and neonatal level of care on outcomes of moderate and late preterm infants. J Perinatol (2024). https://doi.org/10.1038/s41372-024-01901-x

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