Causes and risk factors for infant mortality in Nunavut, Canada 1999–2011

BMC Pediatrics

Laura Arbour⁵  Sharon Edmunds-Potvin³  Laakkuluk Williamson Bathory³  Cheryl Greenberg²  Geraldine Osborne¹  Padma Surmala⁴  Sorcha A Collins⁵ 

[1] Department of Health and Social Services, Government of Nunavut, Iqaluit, NU, Canada;Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, MB, Canada;Nunavut Tunngavik Incorporated, Iqaluit, NU, Canada;Court Services Division, Department of Justice, Government of Nunavut, Iqaluit, NU, Canada;Department of Medical Genetics, University of British Columbia Island Medical Program, University of Victoria, PO Box 1700 STN CSC, Victoria, BC, V8W 2Y2, Canada

关键词: CPT1A P479L variant;    Carnitine palmitoyltransferase 1 deficiency;    Sudden unexpected death in infancy;    Sudden infant death syndrome;    Infant mortality;    Aboriginal;    Nunavut;    Inuit;   

Others  :  1170596
DOI  :  10.1186/1471-2431-12-190

 received in 2012-09-13, accepted in 2012-12-05,  发布年份 2012

【 摘 要 】

Background

The northern territory Nunavut has Canada’s largest jurisdictional land mass with 33,322 inhabitants, of which 85% self-identify as Inuit. Nunavut has rates of infant mortality, postneonatal mortality and hospitalisation of infants for respiratory infections that greatly exceed those for the rest of Canada. The infant mortality rate in Nunavut is 3 times the national average, and twice that of the neighbouring territory, the Northwest Territories. Nunavut has the largest Inuit population in Canada, a population which has been identified as having high rates of Sudden Infant Death Syndrome (SIDS) and infant deaths due to infections.

Methods

To determine the causes and potential risk factors of infant mortality in Nunavut, we reviewed all infant deaths (<1yr) documented by the Nunavut Chief Coroner’s Office and the Nunavut Bureau of Statistics (n=117; 1999–2011). Rates were compared to published data for Canada.

Results

Sudden death in infancy (SIDS/SUDI; 48%) and infection (21%) were the leading causes of infant death, with rates significantly higher than for Canada (2003–2007). Of SIDS/SUDI cases with information on sleep position (n=42) and bed-sharing (n=47), 29 (69%) were sleeping non-supine and 33 (70%) were bed-sharing. Of thosebed-sharing, 23 (70%) had two or more additional risk factors present, usually non-supine sleep position. CPT1A P479L homozygosity, which has been previously associated with infant mortality in Alaska Native and British Columbia First Nations populations, was associated with unexpected infant death (SIDS/SUDI, infection) throughout Nunavut (OR:3.43, 95% CI:1.30-11.47).

Conclusion

Unexpected infant deaths comprise the majority of infant deaths in Nunavut. Although the CPT1A P479L variant was associated with unexpected infant death in Nunavut as a whole, the association was less apparent when population stratification was considered. Strategies to promote safe sleep practices and further understand other potential risk factors for infant mortality (P479L variant, respiratory illness) are underway with local partners.

【 授权许可】

   
2012 Collins et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

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