Comparison of Canadian versus American emergency department visits for acute asthma

Acute asthma is a common emergency department (ED) presentation in both Canada and the United States.

To compare ED asthma management and outcomes between Canada and the United States.

A prospective cohort study of 69 American and eight Canadian EDs was conducted. Patients aged two to 54 years who presented with acute asthma underwent a structured ED interview and telephone follow-up two weeks later.

A total of 3031 patients were enrolled. Canadian patients were more likely to be white (89% versus 22%; P<0.001), have health insurance (100% versus 69%; P<0.001) and identify a primary care provider (89% versus 64%; P<0.001) than American patients. In addition, Canadian patients were more likely to be using inhaled corticosteroids (63% versus 44%; P<0.001) and had higher initial peak expiratory flow (61% versus 48%; P<0.001). In the ED, Canadians received fewer beta-agonist (one versus two; P<0.001) and more anticholinergic (two versus one; P<0.001) treatments in the first hour; use of systemic corticosteroids was similar (60% versus 68%; P=0.13). Canadians were less likely to be hospitalized (11% versus 21%; P=0.02). Corticosteroids were prescribed similarly at discharge (60% versus 69%; P=0.13); however, Canadians were discharged more commonly on inhaled corticosteroids (63% versus 11%; P<0.001) and relapses were similar.

Canadian patients with acute asthma have fewer barriers to primary care and are more likely to be on preventive medications, both before the ED visit and following discharge. Admissions rates are higher in the United States; however, relapse after discharge is similar between countries. These findings highlight the influences of preventive practices and heath care systems on ED visits for asthma.