Out-of-Pocket Spending for Asthma-Related Care Among Commercially Insured Patients, 2004-2016.

Background: Out-of-pocket (OOP) health care costs can cause financial burden and deferred care for many Americans. Little is known about OOP spending for asthma-related care among the commercially insured.

Objectives: To analyze OOP spending for asthma-related care overall, across types of care, and by income.

Methods: Using enrollment, claims, and geocoded census tract data on income from a large US commercial health plan from 2004 to 2016, we measured inflation-adjusted OOP spending for individuals with asthma ages 4 to 64 years (n = 1,986,769). We estimated annual asthma-related OOP spending over time, and average total, asthma-related, asthma type of care, and asthma medication spending by income. We measured trends in median OOP cost per medication. Linear regression models were adjusted for patient covariates and deductible level.

Results: Asthma-related OOP spending decreased over time both for patients enrolled in high-deductible health plans and for those in traditional plans. High-deductible plan enrollment increased from 7% to 54%. Compared with patients living in high-income areas, patients in the lowest-income areas had similar annual total and asthma-related OOP spending, but spent 30% less on controller medications and a higher proportion of their asthma-related OOP spending on inpatient and emergency care (10% vs 3%; P < .001). Asthma-related OOP spending represented a higher proportion of household income for patients in lower-income areas.

Conclusions: Patients with asthma living in the lowest-income areas have greater cost burden, lower spending on controller medications, and greater spending on high-acuity care than higher-income counterparts.