Association between Year of Birth and 1-Year Survival among Extremely Preterm Infants in Sweden during 2004-2007 and 2014-2016

Research output: Contribution to journalArticle

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.

Details

Authors
  • Mikael Norman
  • Boubou Hallberg
  • Thomas Abrahamsson
  • Lars J. Björklund
  • Magnus Domellöf
  • Aijaz Farooqi
  • Cathrine Foyn Bruun
  • Christian Gadsbøll
  • Lena Hellström-Westas
  • Fredrik Ingemansson
  • Karin Källén
  • David Ley
  • Karel Maršál
  • Erik Normann
  • Fredrik Serenius
  • Olof Stephansson
  • Lennart Stigson
  • Petra Um-Bergström
  • Stellan Håkansson
Organisations
External organisations
  • Karolinska Institutet
  • Karolinska University Hospital
  • Norrland University Hospital
  • Linköping University
  • Skåne University Hospital
  • Umeå University
  • Uppsala University
  • Ryhov County Hospital, Jönköping
  • Queen Silvia Children’s Hospital
  • Södersjukhuset
  • Lund University
  • University of Gothenburg
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Pediatrics
Original languageEnglish
Pages (from-to)1188-1199
Number of pages12
JournalJAMA - Journal of the American Medical Association
Volume321
Issue number12
Publication statusPublished - 2019
Publication categoryResearch
Peer-reviewedYes