Abstract
Rationale: Inhaled corticosteroids (ICS) are not first-line therapy for patients with chronic obstructive pulmonary disease (COPD) at low risk of exacerbations, but they are commonly prescribed despite evidence of harm. We consider ICS prescription in this population to be of "low value." The association of low-value ICS with subsequent healthcare utilization and costs is unknown. Understanding this relationship could inform efforts to reduce the delivery of low-value care. Objectives: To determine whether low-value ICS prescribing is associated with higher outpatient healthcare utilization and costs among patients with COPD who are at low risk of exacerbation. Methods: We performed a cohort study between January 1, 2010, and December 31, 2018, identifying a cohort of veterans with COPD who performed pulmonary function tests (PFTs) at 21 Veterans Affairs medical centers nationwide. Patients were defined as having low exacerbation risk if they experienced less than two outpatient exacerbations and no hospital admissions for COPD in the year before PFTs. Our primary exposure was the receipt of an ICS prescription in the 3 months before the date of PFTs. Our primary outcomes were outpatient utilization and outpatient costs in the 1 year after PFTs. For inference, we generated negative binomial models for utilization and generalized linear models for costs, adjusting for confounders. Results: We identified a total of 31,551 patients with COPD who were at low risk of exacerbation. Of these patients, 9,742 were prescribed low-value ICS (mean [standard deviation (SD)] age, 69 [9] yr), and 21,809 were not prescribed low-value ICS (mean [SD] age, 68 [9] yr). Compared with unexposed patients, those exposed to low-value ICS had 0.53 more encounters per patient per year (95% confidence interval CI, 0.23-0.83) and incurred $154.72 higher costs/patient/year (95% CI, $45.58-$263.86). Conclusions: Low-value ICS prescription was associated with higher subsequent outpatient healthcare utilization and costs. Potential mechanisms for the observed association are that 1) low-value ICS may be a marker of poor respiratory symptom control, 2) there is confounding by indication, or 3) low-value ICS results in increased drug costs or utilization. Health systems should identify low-value ICS prescriptions as a target to improve value-based care.