DISCUSSION
The number of pediatric deaths in this case series is similar to what has been reported in other Canadian studies2 and is lower than the number of deaths per population in the United Kingdom1 and the United States 3 . East/Southeast Asian ethnicities were over-represented as this ethnic group only accounts for 8% of the population in British Columbia. The predominance of deaths occurring in children aged 10 to 18 years old is the same as reported in a recent UK inquiry1. All children had severe anoxic brain injury due to out of hospital arrests which identifies that in-hospital management of exacerbations is not contributing to asthma deaths.
Given the rarity of asthma deaths despite the high prevalence of asthma in children, it is important to note that all of the children in this case series had identifiable risk factors for asthma death most commonly: poor adherence to controller medication, overuse of short-acting beta agonists, and a recent exacerbation. Although previous studies identified that use of more than 12 inhalers of reliever in a year increased the risk of death5, a recent study found that this threshold is much lower with the use of more than 3 inhalers associated with an increased risk of death6, which was seen in this series with all children filling more than 3 inhalers but none filling more than 12. A limitation of prescription refill data is that it is not known if short-acting-beta-agonists were used or if they were filled to have additional rescue inhalers on hand. However, refills of rescue inhalers can act as an objective surrogate for asthma control given it is known that patients often overestimate their asthma control when asked7.
Asthma deaths were rare in children but attention should be paid to those with a severe exacerbation (requiring systemic steroids, an ED visit or hospitalization) in the past year, more than three beta-agonist refills in a year and poor adherence to controller medication.
1, 4Yang, CL, MSc, MD
1Cook, VE, MSc, MD
3, 4Carleton, B, BSc, PharmD
2Seear, M, MD
1Division of Respiratory Medicine, Department of Pediatrics, BC Children’s Hospital
2Division of Clinical Immunology and Allergy, Department of Pediatrics, BC Children’s Hospital
3Division of Translational Therapeutics, Department of Pediatrics, University of British Columbia
4BC Children’s Hospital Research Institute
Corresponding Author:connie.yang@cw.bc.ca
Word count 1335
Funding Statement: Financial support was provided in part by the Therapeutic Evaluation Unit of the BC Provincial Health Services Authority
Competing interests: None of the authors have competing interests for the content of this paper
Word count (excluding abstract): 995
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