Inadequate use of asthma medication in the United States: Results of the Asthma in America national population survey

Background: Studies of the use of anti-inflammatory asthma therapy have been limited to selected populations or have been unable to assess the appropriateness of therapy for individuals. Objective: We sought to describe the current use of asthma medication in the United States population and to examine the influence of symptoms and sociodemographics on medication use. Methods: This study was based on a cross-sectional, national, random-digit-dial household telephone survey in 1998 designed to identify adult patients and parents of children with current asthma. Respondents were classified as having current asthma if they had a physician's diagnosis of asthma and were either taking medication for asthma or had asthma symptoms during the past year. Results: One or more persons met the study criteria for current asthma in 3273 (7.8%) households in which a screening questionnaire was completed. Of these, 2509 persons (721 children <16 years) with current asthma were interviewed. Current use of anti-inflammatory medication was reported by 507 (20.1%). Of these, most were using inhaled corticosteroids (72.5%), with use of antileukotrienes reported by 11.4% and use of cromolynnedocromil reported by 18.6%. Of persons with persistent asthma symptoms in the past month, 26.2% reported current use of some form of anti-inflammatory medication. In bivariate analysis persons reporting lower income, less education, and present unemployment, as well as smokers, were significantly (P <.001) less likely to report current anti-inflammatory use than were other populations. In a multiple regression model nonsmokers and those of white, non-Hispanic ethnicity, as well as persons reporting less asthma control, were more likely to report current anti-inflammatory medication use. Conclusion: In the United States use of appropriate asthma therapy remains inadequate. Strategies to increase use of anti-inflammatory therapy among patients with asthma are needed. These might include methods to increase access to asthma care for minorities and the socioeconomically disadvantaged.