The relationship between asthma controller medication use and exacerbation rates over time is unclear at the population level. To estimate the change in asthma controller medication use between 2 time periods as measured by the controller-to-total asthma medication ratio and its association with changes in asthma exacerbation rates between 19971998 and 20042005. The study design was a cross-sectional population-level comparison between individuals from 19971998 and 20042005. Study participants were individuals aged 5 to 56 years identified as having asthma in the Medical Expenditure Panel Survey (MEPS). The main outcome measures were a controller-to-total asthma medication ratio greater than 0.5 and asthma exacerbation rates (dispensing of systemic corticosteroid or emergency department visit/hospitalization for asthma) in 19971998 compared with 20042005. The proportion of individuals with a controller-to-total asthma medication ratio greater than 0.5, when adjusted for other demographic factors, has improved by 16.1% (95% CI: 10.8%, 21.3%) for all individuals from 19971998 to 20042005. Annual asthma exacerbation rates did not change significantly in any group from 19971998 to 20042005 (0.27/year to 0.23/year). African American and Hispanic individuals with asthma had higher asthma exacerbation rates and a lower proportion with a controller-to-total asthma medication ratio greater than 0.5 than whites in both 19971998 and 20042005; however, these differences were not statistically significant. An increase in asthma controller-to-total medication ratio in a sample reflective of the US population was not associated with a decreased asthma exacerbation rate comparing 19971998 and 20042005.
ASJC Scopus subject areas
- Immunology and Allergy
- Pulmonary and Respiratory Medicine