History of asthma in Canada

Abstract

Asthma prevalence in Canada is high and, at least until recently, has been rising. Deaths from asthma have been gradually declining with a small but significant transient increase between about 1975 and 1995, most likely due to the inappropriate use of inhaled ß2 agonists leading to under-treatment with anti-inflammatory agents. Canada has been at the forefront of development of asthma treatments and asthma guidelines. Expressing the spectrum of asthma severity as a continuum rather than a series of steps is unique to the Canadian asthma guidelines. Other Canadian contributions include major participation in GINA, measurement of AHR, measurement of induced sputum cell counts, developments in aerosol science including large volume spacer devices, measurement of asthma quality of life and investigations into occupational asthma.