Overuse of Short Acting Beta-Agonist Medication in Children Enrolled in Indiana's Medicaid Program

Brandt, Amy J

BACKGROUND: Asthma is a common, chronic disease in the United States and Indiana. An estimated 9.5% of children in Indiana have a current asthma diagnosis. The National Heart Lung and Blood Institute’s Guidelines for the Diagnosis and Management of Asthma stress the importance of routine office visits, proper use of quick-relief and controller medications and appropriate short-acting beta₂-agonist (SABA) use. SABA overuse is a potential sign of uncontrolled asthma and can predict poor asthma-related health outcomes such as emergency department (ED) visits, hospitalizations or death. This study seeks to determine the percentage of children with asthma who are overusing SABA medication in Indiana’s Medicaid population and evaluate the relationship between overuse and asthma-related outcomes.

METHODS: Children aged 17 or younger with persistent asthma were identified from Indiana’s 2011 Medicaid administrative claims database. Persistent asthma was defined as having one or more of the following in the study period: 4 or more asthma medication dispensing events, 1 or more ED visit with asthma as the primary diagnosis, 1 or more hospitalization with asthma as the primary diagnosis, or 4 or more asthma-related outpatient visits and 2 or more asthma medication dispensing events. Overuse was defined as having 6 or more SABA refills in a 12 month period. Data were analyzed by prevalence ratios (PR), 95% confidence intervals (95%CI), Wilcoxon rank-sum tests, and logistic regression.

RESULTS:

In 2011, 32,727 children with Medicaid coverage in Indiana had persistent asthma. Of these children, 18.7% overused SABA medications. Demographic profiles of over-users and non-over-users were similar.

A total of 6,761 children with persistent asthma had an asthma-related ED visit in 2011, 16.0% of which overused SABA medications. There was no statistically significant difference (p=0.1693) in the number of ED visits between children who overused SABA medications and those who did not.

A total of 1,024 children with persistent asthma had an asthma-related hospitalization during 2011. Of these, 29.4% overused SABA medications compared to 18.3% with no asthma hospitalization (PR: 1.81, 95%CI: 1.62-2.13). Adjusting for demographic covariates, SABA over-users were 1.87 (95%CI: 1.63-2.14) times more likely to have an asthma hospitalization than those who did not overuse.

CONCLUSIONS:

In 2011, one in five children with persistent asthma overused SABA medications in Indiana’s Medicaid population. Overuse was associated with increased risk of being hospitalized. One in three children with persistent asthma who overused SABA medication experienced a hospitalization during the study timeframe.