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Canadian Journal of Public Health

, Volume 104, Issue 3, pp e187–e192 | Cite as

Neighbourhood Income and Neonatal, Postneonatal and Sudden Infant Death Syndrome (SIDS) Mortality in Canada, 1991–2005

  • Nicolas L. GilbertEmail author
  • Nathalie Auger
  • Russell Wilkins
  • Michael S. Kramer
Quantitative Research

Abstract

Background

Rates of infant mortality declined in Canada in the 1990s and 2000s, but the extent to which all socio-economic levels benefitted from this progress is unknown.

Objectives

This study investigated differences and time trends in neonatal, postneonatal and sudden infant death syndrome (SIDS) mortality across neighbourhood income quintiles among live births in Canada from 1991 through 2005.

Methods

The Canadian linked live birth and infant death file was used, excluding births from Ontario, Yukon, Northwest Territories and Nunavut. Mortality rates for neonatal, postneonatal and sudden infant death syndrome (SIDS) were calculated by neighbourhood income quintile and period (1991–1995, 1996–2000, 2001–2005). Hazard ratios (HR) for neighbourhood income quintile and period were computed, adjusting for province of residence, maternal age, parity, infant sex and multiple birth.

Results

In urban areas, for the entire study period (1991–2005), the poorest neighbourhood income quintile had a higher hazard of neonatal death (adjusted HR 1.24, 95% CI 1.15–1.34), postneonatal death (adjusted HR 1.58, 95% CI 1.41–1.76) and SIDS (adjusted HR 1.83, 95% CI 1.49–2.26) compared to the richest quintile. Postneonatal and SIDS mortality rates declined by 37% and 57%, respectively, between 1991–1995 and 2001–2005 whereas no significant change was observed in neonatal mortality. The decrease in postneonatal and SIDS mortality rates occurred across all income quintiles.

Conclusion

This study shows that despite a decrease in infant mortality and SIDS across all neighbourhood income quintiles over time in Canada, socio-economic inequalities persist. This finding highlights the need for effective infant health promotion strategies in vulnerable populations.

Key Words

Infant mortality social class sudden infant death 

Résumé

Contexte

La mortalité infantile a diminué au Canada depuis les années 1990 et 2000 mais nous ignorons si toutes les classes socioéconomiques ont bénéficié également de ce progrès.

Objectifs

La présente étude portait sur les différences entre les taux de mortalité néonatale et postnéonatale et de mort subite du nourrisson entre les différents quintiles de revenu des quartiers au Canada de 1991 à 2005.

Méthodes

Le fichier couplé des naissances vivantes et des décès infantiles au Canada a été utilisé à l’exclusion des naissances survenues en Ontario, au Yukon, dans les Territoires du Nord-ouest et au Nunavut. Les taux de mortalité néonatale et postnéonatale et de mort subite du nourrisson ont été calculé par quintile de revenu des quartiers et par période (1991–1995, 1996–2000, 2001–2005). Les rapports de risque (RR) ont été calculés par quintile de revenu et période avec ajustement pour la province de résidence, l’âge de la mère, la parité, le sexe du nourrisson et les naissances multiples.

Résultats

En zone urbaine, pour toute la période étudiée (1991–2005), le quintile de revenu le plus pauvre avait un risque plus élevé de mortalité néonatale (RR ajusté 1,24; IC 95% 1,15–1,34), de mortalité postnéonatale (RR ajusté 1,58; IC 95% 1,41–1,76) et de mort subite du nourrisson (RR ajusté 1,83; IC 95% 1,49–2,26) par rapport au quintile le plus riche. Les taux de mortalité post néonatale et de mort subite du nourrisson ont décliné respectivement de 37 % et de 57 % de 1991–1995 à 2001–2005 alors que le taux de mortalité néonatale n’a pas changé de façon significative. Cette diminution de la mortalité postnéonatale et de la mort subite du nourrisson a été observée dans tous les quintiles de revenu.

Conclusion

Malgré une diminution de la mortalité postnéonatale et du syndrome de mort subite du nourrisson dans tous les quintiles de revenu, les inégalités subsistent au Canada. Ce résultat démontre le besoin de stratégies efficaces de promotion de la santé visant spécifiquement les populations vulnérables.

Mots Clés

mort subite du nourrisson mortalité infantile statut socioéconomique 

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Copyright information

© The Canadian Public Health Association 2013

Authors and Affiliations

  • Nicolas L. Gilbert
    • 1
    • 2
    Email author
  • Nathalie Auger
    • 2
    • 3
  • Russell Wilkins
    • 4
    • 5
  • Michael S. Kramer
    • 6
  1. 1.Maternal and Infant Health SectionPublic Health Agency of CanadaOttawaCanada
  2. 2.Department of Social and Preventive MedicineUniversité de MontréalMontréalCanada
  3. 3.Institut national de santé publique du QuébecMontréalCanada
  4. 4.Health Analysis DivisionStatistics CanadaOttawaCanada
  5. 5.Department of Epidemiology and Community MedicineUniversity of OttawaOttawaCanada
  6. 6.Departments of Pediatrics and of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontréalCanada

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