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The DOI matches its Crossref record; 35 of the 35 references it cites were found in a registry or an index.

Association Between Year of Birth and 1-Year Survival Among Extremely Preterm Infants in Sweden During 2004-2007 and 2014-2016

Open access
Norman, Mikael, Hallberg, Boubou, Abrahamsson, Thomas, Björklund, Lars J., Domellöf, Magnus, Farooqi, Aijaz, Foyn Bruun, Cathrine, Gadsbøll, Christian, Hellström-Westas, Lena, Ingemansson, Fredrik, Källén, Karin, Ley, David, Maršál, Karel, Normann, Erik, Serenius, Fredrik, Stephansson, Olof, Stigson, Lennart, Um-Bergström, Petra, Håkansson, Stellan·2019·JAMA

Abstract

Importance: Since 2004-2007, national guidelines and recommendations have been developed for the management of extremely preterm births in Sweden. If and how more uniform management has affected infant survival is unknown. Objective: To compare survival of extremely preterm infants born during 2004-2007 with survival of infants born during 2014-2016. Design, Setting and Participants: All births at 22-26 weeks’ gestational age (n = 2205) between April 1, 2004, and March 31, 2007, and between January 1, 2014, and December 31, 2016, in Sweden were studied. Prospective data collection was used during 2004-2007. Data were obtained from the Swedish pregnancy, medical birth, and neonatal quality registries during 2014-2016. Exposures: Delivery at 22-26 weeks’ gestational age. Main Outcomes and Measures: The primary outcome was infant survival to the age of 1 year. The secondary outcome was 1-year survival among live-born infants who did not have any major neonatal morbidity (specifically, without intraventricular hemorrhage grade 3-4, cystic periventricular leukomalacia, necrotizing enterocolitis, retinopathy of prematurity stage 3-5, or severe bronchopulmonary dysplasia). Results: During 2004-2007, 1009 births (3.3/1000 of all births) occurred at 22-26 weeks’ gestational age compared with 1196 births (3.4/1000 of all births) during 2014-2016 (P = .61). One-year survival among live-born infants at 22-26 weeks’ gestational age was significantly lower during 2004-2007 (497 of 705 infants [70%]) than during 2014-2016 (711 of 923 infants [77%]) (difference, −7% [95% CI, −11% to −2.2%], P = .003). One-year survival among live-born infants at 22-26 weeks’ gestational age and without any major neonatal morbidity was significantly lower during 2004-2007 (226 of 705 infants [32%]) than during 2014-2016 (355 of 923 infants [38%]) (difference, −6% [95% CI, −11% to −1.7%], P = .008). Conclusions and Relevance: Among live births at 22-26 weeks’ gestational age in Sweden, 1-year survival improved between 2004-2007 and 2014-2016.

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Metadata

Authors
Norman, M., Hallberg, B., Abrahamsson, T., Björklund, L. J., Domellöf, M., Farooqi, A., Foyn Bruun, C., Gadsbøll, C., Hellström-Westas, L., Ingemansson, F., Källén, K., Ley, D., Maršál, K., Normann, E., Serenius, F., Stephansson, O., Stigson, L., Um-Bergström, P., & Håkansson, S.
Venue
JAMA
Published
2019-03-26
Volume
321
Issue
12
Pages
1188
ISSN
  • 0002-9955 (ISSN-L)
  • 0098-7484
OpenAlex
W2923852139
Cited by
316
References
35
FWCI
39.11
Type
journal article
Language
en
Open access
bronze

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Norman, M., Hallberg, B., Abrahamsson, T., Björklund, L. J., Domellöf, M., Farooqi, A., Foyn Bruun, C., Gadsbøll, C., Hellström-Westas, L., Ingemansson, F., Källén, K., Ley, D., Maršál, K., Normann, E., Serenius, F., Stephansson, O., Stigson, L., Um-Bergström, P., & Håkansson, S. (2019). Association Between Year of Birth and 1-Year Survival Among Extremely Preterm Infants in Sweden During 2004-2007 and 2014-2016. JAMA. https://doi.org/10.1001/jama.2019.2021

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

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