Abstract
Objective:
To compare risk-adjusted changes in outcomes of preterm infants <29 weeks gestation born in 1996 to 1997 with those born in 2006 to 2007.
Study Design:
Observational retrospective comparison of data from 15 units that participated in the Canadian Neonatal Network during 1996 to 1997 and 2006 to 2007 was performed. Rates of mortality and common neonatal morbidities were compared after adjustment for confounders.
Result:
Data on 1897 infants in 1996 to 1997 and 1866 infants in 2006 to 2007 were analyzed. A higher proportion of patients in the later cohort received antenatal steroids and had lower acuity of illness on admission. Unadjusted analyses revealed reduction in mortality (unadjusted odds ratio (UAOR): 0.83, 95% confidence interval (CI): 0.63, 0.98), severe retinopathy (UAOR: 0.68, 95% CI: 0.50 to 0.92), but increase in bronchopulmonary dysplasia (UAOR: 1.61, 95% CI: 1.39 to 1.86) and patent ductus arteriosus (UAOR: 1.22, 95% CI: 1.07 to 1.39). Adjusted analyses revealed increases in the later cohort for bronchopulmonary dysplasia (adjusted odds ratio (AOR): 1.88, 95% CI: 1.60 to 2.20) and severe neurological injury (AOR: 1.49, 95% CI: 1.22 to 1.80). However, the ascertainment methods for neurological findings and ductus arteriosus differed between the two time periods.
Conclusion:
Improvements in prenatal care has resulted in improvement in the quality of care, as reflected by reduced severity of illness and mortality. However, after adjustment of prenatal factors, no improvement in any of the outcomes was observed and on the contrary bronchopulmonary dysplasia increased. There is need for identification and application of postnatal strategies to improve outcomes of extreme preterm infants.
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Acknowledgements
This study was supported by Grant MOP-53115 from the Canadian Institutes of Health Research. Additional funding was provided by participating hospitals. We thank Woojin Yoon for statistical support of this project. Canadian Neonatal Network coordinating center (Mother-Infant Care Research Center) is supported by Ministry of Health and Long-term Care, Ontario, Canada. Funding agencies had no role in design, collection, analyses or interpretation of results of this study.
Source of funding: Please see Appendix.
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Presented at the Annual Meeting of the Pediatric Academy Societies, Vancouver, May 2010.
Site Investigators of the Canadian Neonatal Network Shoo K Lee (Director, Canadian Neonatal Network); Prakesh S Shah (Associate Director, Canadian Neonatal Network); Wayne Andrews (Janeway Children's Health and Rehabilitation Centre, St John's, NL); Keith Barrington (St Justine's Hospital, Montreal, QC); Wendy Yee (Foothills Medical Centre, Calgary, AB); Barbara Bullied (Everett Chalmers Hospital, Fredericton, NB); Rody Canning (Moncton Hospital, Moncton, NB); Gerarda Cronin (St Boniface General Hospital, Winnipeg, MB); Kimberly Dow (Kingston General Hospital, Kingston, ON); Michael Dunn (Sunnybrook Health Sciences Centre, Toronto, ON); Adele Harrison (Victoria General Hospital, Victoria, BC); Andrew James (Sick Kids Hospital, Toronto, ON); Zarin Kalapesi (Regina General Hospital, Regina, SK); Lajos Kovacs (Jewish General Hospital, Montreal, QC); Orlando da Silva (St Joseph's Health Centre; London, ON); Douglas D McMillan (IWK Health Centre, Halifax, NS); Prakesh Shah (Mount Sinai Hospital, Toronto, ON); Cecil Ojah (St John Regional Hospital, St John, NB); Abraham Peliowski/Khalid Aziz (Royal Alexandra Hospital, Edmonton, AB); Bruno Piedboeuf (Centre Hospitalier Universitaire de Quebec, Sainte Foy, QC); Patricia Riley (Montreal Children's Hospital, Montreal, QC); Daniel Faucher (Royal Victoria Hospital, Montreal, QC); Nicole Rouvinez-Bouali (Children's Hospital of Eastern Ontario, Ottawa, ON); Koravangattu Sankaran (Royal University Hospital, Saskatoon, SK); Mary Seshia (Health Sciences Centre, Winnipeg, MB); Sandesh Shivananda (Hamilton Health Sciences Centre, Hamilton, ON); Zenon Cieslak (Royal Columbian Hospital, New Westminster, BC); Anne Synnes (Children's and Women's Health Centre of British Columbia, Vancouver, BC); and Herve Walti (Centre Hospitalier Universitaire de Sherbrooke, Fleurimont, QC).
Contribution of authors
Prakesh S Shah: initiated concept, developed draft, analyzed data and wrote the manuscript; Koravangattu Sankaran: participated in design, review of protocol and manuscript writing; Khalid Aziz: participated in design, concept, and revision and editing of the manuscript; Alexander C Allen: participated in design, interpretation and revision of the manuscript; Mary Seshia: initiated concept, participated in design, contributed in writing and editing of the manuscript; Arne Ohlsson: initiated concept, participated in design, contributed in writing and editing of the manuscript; and Shoo K Lee: participated in the design of study, review of results and manuscript preparation.
Appendix
Appendix
Site Investigators of the Canadian Neonatal Network
Shoo K Lee (Director, Canadian Neonatal Network); Prakesh S Shah (Associate Director, Canadian Neonatal Network); Wayne Andrews (Janeway Children's Health and Rehabilitation Centre, St John's, NL); Keith Barrington (St Justine's Hospital, Montreal, QC); Wendy Yee (Foothills Medical Centre, Calgary, AB); Barbara Bullied (Everett Chalmers Hospital, Fredericton, NB); Rody Canning (Moncton Hospital, Moncton, NB); Gerarda Cronin (St Boniface General Hospital, Winnipeg, MB); Kimberly Dow (Kingston General Hospital, Kingston, ON); Michael Dunn (Sunnybrook Health Sciences Centre, Toronto, ON); Adele Harrison (Victoria General Hospital, Victoria, BC); Andrew James (Sick Kids Hospital, Toronto, ON); Zarin Kalapesi (Regina General Hospital, Regina, SK); Lajos Kovacs (Jewish General Hospital, Montreal, QC); Orlando da Silva (St Joseph's Health Centre; London, ON); Douglas D McMillan (IWK Health Centre, Halifax, NS); Prakesh Shah (Mount Sinai Hospital, Toronto, ON); Cecil Ojah (St John Regional Hospital, St John, NB); Abraham Peliowski/Khalid Aziz (Royal Alexandra Hospital, Edmonton, AB); Bruno Piedboeuf (Centre Hospitalier Universitaire de Quebec, Sainte Foy, QC); Patricia Riley (Montreal Children's Hospital, Montreal, QC); Daniel Faucher (Royal Victoria Hospital, Montreal, QC); Nicole Rouvinez-Bouali (Children's Hospital of Eastern Ontario, Ottawa, ON); Koravangattu Sankaran (Royal University Hospital, Saskatoon, SK); Mary Seshia (Health Sciences Centre, Winnipeg, MB); Sandesh Shivananda (Hamilton Health Sciences Centre, Hamilton, ON); Zenon Cieslak (Royal Columbian Hospital, New Westminster, BC); Anne Synnes (Children's and Women's Health Centre of British Columbia, Vancouver, BC); and Herve Walti (Centre Hospitalier Universitaire de Sherbrooke, Fleurimont, QC).
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Shah, P., Sankaran, K., Aziz, K. et al. Outcomes of preterm infants <29 weeks gestation over 10-year period in Canada: a cause for concern?. J Perinatol 32, 132–138 (2012). https://doi.org/10.1038/jp.2011.68
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DOI: https://doi.org/10.1038/jp.2011.68
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