| Asthma affects approximately 10% of the population at some time in their lives and the prevalence of asthma is increasing worldwide (1-5). In the last decade, the prevalence of asthma has increased substantially, particularly in the populations of Europe, North America and in certain parts of the southern hemisphere (Australia and New Zealand). With respect to Canada, notable increases in asthma morbidity and mortality have occurred in the Prairie Provinces (5).;In the vast majority of cases asthma can be controlled by allergen avoidance and/or appropriate medication. A visit to the emergency department (ED) for asthma may represent a breakdown in the treatment/control process. The factors that determine why one asthmatic requires emergency department treatment during an exacerbation, while others do not, remain obscure. Emergency department treatment for asthma is a significant health care expenditure and an exacerbation of asthma compromises the quality of life of asthmatics.;Rationale. In most instances asthma is a controllable disease. An ED visit represents a breakdown in control. Identification of characteristics of those with asthma who come to the ED, specifically, characteristics that distinguish them from other people with asthma, may assist in the design of interventions aimed at improving asthma control and reducing the need for this type of treatment.;Purpose. The major objective of this study was to identify the risk factors associated with an exacerbation of asthma serious enough to warrant emergency department treatment by comparing the features of those who sought treatment for asthma in the emergency department (ED cases) to a random sample of people with asthma in the same communities (RDD controls).;Methods. A comparative analysis of those who attended the ED (n = 337) for asthma treatment with community asthmatics located through random digit dialling (RDD)(n = 212). Participants completed a mailed questionnaire.;Analysis. Bivariate analysis of specific risk factors, followed by multivariate model development with logistic regression.;Conclusions. Bivariate analysis revealed that the ED asthmatic was more likely than the RDD asthmatic to have had asthma for less than 5 years. Logistic regression revealed that the ED asthmatic is more apt to be younger, have seen their family doctor in the last year, to use the ED more than once a year, and to report more severe disease. Differences between the ED and RDD asthmatic may relate to both asthma control and disease severity. The highest risk group appears to be the young adult with moderate to severe asthma. This group would be an appropriate target for intervention/prevention programs. Clinicians should be alert to signs of deteriorating asthma control and be willing to monitor these patients. |
