Estimating the impact of self-management education, influenza vaccines, nebulizers, and spacers on health utilization and expenditures for Medicaid-enrolled children with asthma

Introduction: We quantify the effect of a set of interventions including asthma self-management education, influenza vaccination, spacers, and nebulizers on healthcare utilization and expenditures for Medicaid-enrolled children with asthma in New York and Michigan. Methods: We obtained patients’ data from Medicaid Analytic eXtract files and evaluated patients with persistent asthma in 2010 and 2011. We used difference-in-difference regression to quantify the effect of the intervention on the probability of asthma-related healthcare utilization, asthma medication, and utilization costs. We estimated the average change in outcome measures from pre-intervention/intervention (2010) to post-intervention (2011) periods for the intervention group by comparing this with the average change in the control group over the same time horizon. Results: All of the interventions reduced both utilization and asthma medication costs. Asthma self-management education, nebulizer, and spacer interventions reduced the probability of emergency department (20.8–1.5%, 95%CI 19.7–21.9% vs. 0.5–2.5%, respectively) and inpatient (3.5–0.8%, 95%CI 2.1–4.9% vs. 0.4–1.2%, respectively) utilizations. Influenza vaccine decreased the probability of primary care physician (6–3.5%, 95%CI 4.4–7.6% vs. 1.5–5.5%, respectively) visit. The reductions varied by state and intervention. Conclusions: Promoting asthma self-management education, influenza vaccinations, nebulizers, and spacers can decrease the frequency of healthcare utilization and asthma-related expenditures while improving medication adherence.