Potential savings from increasing adherence to inhaled corticosteroid therapy in Medicaid-enrolled children

Abstract

Background: Many asthma-related exacerbations could be prevented by consistent use of daily inhaled corticosteroid therapy (ICS-Rx).

Objectives: We sought to measure the potential cost savings that could accrue from increasing ICS-Rx adherence in children.

Study design: We measured observed costs for a cohort of 43,156 Medicaid-enrolled children in 14 southern states whose initial ICS-Rx was prescribed in 2007.

Methods: Adherence rates and associated costs were calculated from Medicaid claims. Children were categorized as high or low adherence based on the ratio of ICS-Rx claims filled to total asthma drug claims. Branching tree simulation was used to project the potential cost savings achieved by increasing the proportion of children with ICS-Rx to total asthma Rx ratios greater than 0.5 to 20%, 40%, 60%, 80%, and 100%.

Results: Increasing the proportion of children who maintain higher adherence after initial ICS-Rx to 40% would generate savings of $95 per child per year. An intervention costing $10 per member per month that resulted in even half of the children maintaining high adherence would generate a 98% return on investment for managed care plans or state Medicaid programs. Net costs decreased incrementally at each level of increase in ICS-Rx adherence. The projected Medicaid cost savings for these 14 states in 2007 ranged from $8.2 million if 40% of the children achieved high adherence, to $57.5 million if 80% achieved high adherence.

Conclusions: If effective large-scale interventions can be found, there are substantial cost savings to be gained from even modest increases in real-world adherence to ICS-Rx among Medicaid-enrolled children with asthma.

Figure. Model Structure of Decision Tree Analysis

ED indicates emergency department; ICS-Rx, inhaled corticosteroid. Initial model uses outcomes for observed high adherence rate of 33.3% to establish baseline costs; model then is rerun at simulated proportions of children in high-adherence group of 40%, 60%, 80%, and 100% to assess potential reductions in costs.