Controller Medication Use and Exacerbations for Children and Adults With Asthma in High-Deductible Health Plans

Importance High-deductible health plans (HDHPs) are increasingly common and associated with decreased medication use in some adult populations. How children are affected is less certain. Objective To examine the association between HDHP enrollment and asthma controller medication use and exacerbations. Design, Setting, and Participants For this longitudinal cohort study with a difference-in-differences design, data were obtained from a large, national, commercial (and Medicare Advantage) administrative claims database between January 1, 2002, and December 31, 2014. Children aged 4 to 17 years and adults aged 18 to 64 years with persistent asthma who switched from traditional plans to HDHPs or remained in traditional plans (control group) by employer choice during a 24-month period were identified. A coarsened exact matching technique was used to balance the groups on characteristics including employer and enrollee propensity to have HDHPs. In most HDHPs, asthma medications were exempt from the deductible and subject to copayments. Statistical analyses were conducted from August 13, 2019, to January 19, 2021. Exposure Employer-mandated HDHP transition. Main Outcomes and Measures Thirty-day fill rates and adherence (based on proportion of days covered [PDC]) were measured for asthma controller medications (inhaled corticosteroid [ICS], leukotriene inhibitors, and ICS long-acting β-agonists [ICS-LABAs]). Asthma exacerbations were measured by rates of oral corticosteroid bursts and asthma-related emergency department visits among controller medication users. Results The HDHP group included 7275 children (mean [SD] age, 10.8 [3.3] years; 4402 boys [60.5%]; and 5172 non-Hispanic White children [71.1%]) and 17 614 adults (mean [SD] age, 41.1 [13.4] years; 10 464 women [59.4%]; and 12 548 non-Hispanic White adults [71.2%]). The matched control group included 45 549 children and 114 141 adults. Compared with controls, children switching to HDHPs experienced significant absolute decreases in annual 30-day fills only for ICS-LABA medications (absolute change, −0.04; 95% CI, −0.07 to −0.01). Adults switching to HDHPs did not have significant reductions in 30-day fills for any controllers. There were no statistically significant differences in PDC, oral steroid bursts, or asthma-related emergency department visits for children or adults. For the 9.9% of HDHP enrollees with health savings account–eligible HDHPs that subjected medications to the deductible, there was a significant absolute decrease in PDC for ICS-LABA compared with controls (−4.8%; 95% CI, −7.7% to −1.9%). Conclusions and Relevance This cohort study found that in a population where medications were exempt from the deductible for most enrollees, HDHP enrollment was associated with minimal or no reductions in controller medication use for children and adults and no change in asthma exacerbations. These findings suggest a potential benefit from exempting asthma medications from the deductible in HDHPs.